Agenda packet — Modesto City Council, June 23, 2026 (part 4 of 7)

Section 226202 et. Seq. of the Act require the legislative body (the Council) to take the following actions prior to August 10th of each year:

1. Adopt a resolution which generally describes any proposed new improvements or any substantial changes in existing improvements and orders the preparation and filing of the Annual Engineer’s Report. This action was taken by Council on March 3, 2026 by Resolution 2026-56.

2. Adopt a resolution approving the Engineer’s Annual Report as submitted or as modified by the City Council. This action was taken by Council on June 2, 2026 by Resolution 2026-172.

3. Adopt a resolution of intention to levy and collect assessments within LMAD No. 1 for the fiscal year. This action was taken by Council on June 2, 2026 by Resolution 2026-172

4. Conduct a public hearing.

5. Adopt a resolution confirming the diagram and assessment as originally proposed or as changed by the legislative body.

DISCUSSION:

LMAD No. 1 is located east of North McClure Road and southwest of MID Lateral #2 and west of Claus Road. It is comprised of 749 single-family residential lots and three (3) public agency owned parcels. When LMAD No. 1 was formed, no annual escalator was adopted. Annual assessments in LMAD No. 1 have remained the same since 1988.

No new improvements or substantial changes to the existing improvements are being proposed. Annual Assessments fund services such as common-area and right-of-way landscaping, water utilities for landscaping, and staff time for program management.

The City Clerk gave notice regarding the public hearing by publishing the appropriate notice in the Modesto Bee on June 12, 2026. All interested people will be afforded an opportunity to be heard during the public hearing. Should there be any protests, whether written or oral, the Council may choose to continue the hearing to a later date, may change any part of the Engineer’s Annual Report to address the concerns of the property owner(s), or may adopt the assessment as proposed.

FISCAL IMPACT:

In Fiscal Year 2025-26, $19,474 (749 parcels at $26.00 per parcel) was levied within LMAD No. 1 while its projected expenses are $24,527.00. 2 Section 22620 et. seq. of the Landscape and Lighting Act of 1972 #17..
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City Council, June 23, 2026
Fiscal Year 2026-27 Annual Assessment for Landscape Maintenance Assessment District No. 1

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The projected expenses for Fiscal Year 2026-27 are $19,216.00, while its projected revenue is $19,474. The expenses include contracted maintenance expenses, utility service charges, and City staff time associated with administration and maintenance of LMAD No. 1. All expenses and revenue are allocated through Fund 6480 Landscape Maintenance Assessment District No. 1. It is the expectation that all expenses for LMAD No. 1 will be paid by the assessments levied on properties within LMAD No. 1. Costs in excess of the tax levy will be paid from the fund balance. When the fund balance is depleted, service levels will need to be adjusted to maintain the service level within budget unless the property owners approve a Proposition 218 vote to increase the tax levy amount to a level sufficient to maintain or increase service levels.

All single-family residential parcels are levied at a flat rate of $26.00 per parcel. Each year, the annual assessment uses a standard formula to calculate its fees: the annual assessments levied are calculated by multiplying the total number of parcels by the flat rate. Each parcel receives equal benefits from the District.

Additionally, the Stanislaus County Auditor-Controller’s Office, Property Taxes and Assessments Division, collects a $0.20 fee per assessment and per parcel. This fee is assessed directly by Stanislaus County and is in addition to the annual assessment being levied for LMAD No. 1.

COMMITTEE RECOMMENDATION:

This item is the approval of the annual levy as directed by the City Council through the approval of the Resolution of Intention on June 2, 2026.

RECOMMENDED COUNCIL ACTION:

Staff Recommendations:

Resolution ordering the levy and collection of such charges as shown within the Engineer’s Annual Report within Landscape Maintenance Assessment District No. 1 for Dry Creek Meadows Subdivisions Nos. 1-6 for Fiscal Year 2026-27.

Approved by:

Jessica Hill, Director of Community
and Economic Development
Joseph P. Lopez, City Manager
Attachments:

1. Resolution

2. LMAD No. 1 Boundary Map

3. LMAD No. 1 2025-26 Engineer’s Annual Report
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MODESTO CITY COUNCIL
RESOLUTION NO. 2026-XX

RESOLUTION ORDERING THE LEVY AND COLLECTION OF SUCH
CHARGES AS SHOWN WITHIN THE ENGINEER’S REPORT WITHIN
LANDSCAPE MAINTENANCE ASSESSMENT DISTRICT NO. 1 FOR DRY CREEK MEADOWS SUBDIVISIONS NOS. 1-6 FOR FISCAL YEAR 2026-27 WHEREAS, on June 2, 2026, by Resolution No. 2026-172, Council declared its intent to levy charges or assessment for the purpose of administering the maintenance of landscaping in the public right-of-way within the street medians and adjacent to the access control walls in Dry Creek Meadows Subdivisions Nos. 1-6 under the provisions of the California Streets and Highways Code Sections 22500 through 22679, more commonly known as the Landscape and Lighting Act of 1972; and
WHEREAS, the charges against the real property are not levied with regards to property values but rather by the allocated cost shown within the Engineer’s Annual Report; and
WHEREAS, the amount of the assessment for Fiscal Year 2026-27 will not increase over the amount imposed for Fiscal Year 2025-26, it will remain at $19,474; and
WHEREAS, a public hearing was held on June 23, 2026; and WHEREAS, the City of Modesto has determined and certifies that the charges are either exempt from or in compliance with all the provisions of Proposition 218, which was passed by the voters in November 1996. The City of Modesto has further determined the charges are in compliance with all the laws pertaining to the levy of such charges.
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NOW, THEREFORE, BE IT RESOLVED by the Council of the City of Modesto that is hereby orders the levy and collection of such charges shown within the Engineer’s Annual Report within Landscape Maintenance Assessment District No. 1 for Dry Creek Meadows Subdivisions Nos. 1-6 for Fiscal Year 2026-

27. BE IT FURTHER RESOLVED that a certified copy of this resolution and attached documentation shall be delivered to the Auditor-Controller of the County of Stanislaus for placement of such charges on the 2026-27 County Tax Roll.

BE IT FURTHER RESOLVED that the diagram of said assessment district, which is attached hereto, and amount of levy thereon is hereby confirmed. #17..
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The foregoing resolution was introduced at a regular meeting of the Council of the City of Modesto held on the 23rd day of June, 2026, by Councilmember _____, who moved its adoption, which motion being duly seconded by Councilmember ______, was upon roll call carried and the resolution adopted by the following vote:

AYES: Councilmembers:

NOES: Councilmembers:

ABSENT: Councilmembers:

ATTEST: _____________________________
DIANE NAYARES-PEREZ, City Clerk
(SEAL)
APPROVED AS TO FORM:

BY: ______________________________
JOSE M. SANCHEZ, City Attorney
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CITY OF MODESTO

COUNCIL AGENDA REPORT
DATE OF MEETING:

June 23, 2026
Date: May 6, 2026
TO: Mayor and City Council
THROUGH: Joseph P. Lopez, City Manager
FROM: Jessica Hill, Director of Community and Economic Development SUBJECT: Fiscal Year 2026-27 Annual Assessment for Landscape Maintenance Assessment District No. 2
CONTACT: Edgar Garcia, Community Development Manager
[email protected], 209-577-5211
DESCRIPTION:

Hearing to consider approving Fiscal Year 2026-27 Diagram and Annual Assessment and ordering the Levy and Collection of Charges within Landscape Maintenance Assessment District No. 2 for Dry Creek Meadows Subdivisions Nos. 7-10, Creekwood Meadows Subdivision and Yosemite Meadows Subdivisions Units 1 and 2. (Funding Source: Landscape Maintenance District No. 2)
STRATEGIC PLAN ELEMENT:

The recommended action supports the City of Modesto’s 2025-2026 Strategic Plan, Goal D to provide safe, efficient, and reliable infrastructure through proactive community investment, maintenance, and sustainability efforts.

BACKGROUND:

On April 4, 1989, the Landscape Maintenance Assessment District No. 2 (LMAD No. 2) by Resolution No. 89-460, was formed in accordance with California Streets and Highways Code Sections 22500 through 22679, more commonly known as the Landscape and Lighting Act of 19751 (the Act). LMAD No. 2 provides funding for the landscape maintenance in the public right-of-way within street medians and areas adjacent to the concrete block walls in Dry Creek Meadows Subdivisions Nos. 7-10, Creekwood Meadows Subdivision, and Yosemite Meadows Units 1 and 2. LMAD No. 2 1 Landscape and Lighting Act of 1972
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City Council, June 23, 2026
Fiscal Year 2026-27 Annual Assessment for Landscape Maintenance Assessment District No. 2

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is located east of North McClure Road, south of Mechalys Way, west of Yosemite Meadows Drive, and north of Yosemite Boulevard. A boundary map is provided as Attachment 2.

Section 226202 et. Seq of the Act requires the legislative body (the Council) to take the following actions prior to August 10th of each year:

2. Adopt a resolution approving the Engineer’s Annual Report as submitted or as modified by the City Council. This action was taken by Council on June 2, 2026 by Resolution No. 2026-173

3. Adopt a resolution of intention to levy and collect assessments within LMAD No. 1 for the fiscal year. This action was taken by Council on June 2, 2026 by Resolution No. 2026-173

4. Conduct a public hearing.

5. Adopt a resolution confirming the diagram and assessment as originally proposed or as changed by the legislative body.

DISCUSSION:

In June 2000, staff successfully completed a Proposition 218 ballot measure which increased the annual assessment and added an annual inflator based on the Building Cost Index (BCI). On June 6, 2000, by Resolution No. 2000-276, Council ordered the hearing scheduled for July 25, 2000. Ballots were then mailed to all LMAD No. 2 property owners asking them to approve an increase in the Fiscal Year 2000-01 assessment and an increase based on the BCI. On July 25, 2000, the Council oversaw the counting of the ballots; the results of the election were as follows: 127.34 in favor and 98.1 opposed. The Council then ordered the levy and collections of charges within LMAD No. 2 by Resolution No. 2000-394.

Annual assessments in LMAD No. 2 have risen incrementally since 2001 pursuant to the annual adjustment. Each year the annual inflator has been applied with the exception of Fiscal Years 2014-15 and 2025-26. In Fiscal Year 2025-26, the BCI was negative so no inflator was applied. The annual assessment is adjusted according to the BCI for the San Francisco Bay Area as reported in the Engineering News Record for the second week of February. The percentage change in the BCI for Fiscal Year 2026-27 is

1.80208%. The proposed assessment for LMAD No. 2 for Fiscal Year 2026-27 is 2 Section 22620 et. seq. of the Landscape and Lighting Act of 1972 #18..
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City Council, June 23, 2026
Fiscal Year 2026-27 Annual Assessment for Landscape Maintenance Assessment District No. 2

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$34,820.85. ($259.52 per acre for commercial properties and $51.16 for each residential property).

The City Clerk gave notice of tonight’s public hearing by publishing the appropriate notice in the Modesto Bee on June 12, 2026. All interested people will be afforded an opportunity to be heard during the public hearing. Should there be any protests, whether written or oral, the Council may choose to continue the hearing to a later date, may change any part of the Engineer’s Annual Report to address the concerns of the property owner(s), or may adopt the assessment as proposed.

FISCAL IMPACT:

In Fiscal Year 2025-26, the total assessment levied was $34,820.85, and its projected expenses were $46,635.30.

The projected expenses for Fiscal Year 2026-27 are $50,405.00, while the projected revenue is $34,820.85. The expenses include contracted maintenance expenses, utility service charges, and City staff time associated with administration and maintenance of LMAD No. 2. Any surplus funds serve as reserves to carry out continued services during the time between the assessment and when the levy is received and to ensure that any delinquent parcels are offset to maintain the continuity of service in the event that there is an above-average delinquency rate.

Each year the annual assessment uses a standard formula to calculate its fees: apply the BCI Inflator to the previous year’s assessment, if applicable, divide the current calendar year BCI by the previous calendar year BCI to obtain your increase percentage, multiply the previous year assessment by the percentage increase, if applicable to determine your assessment amount, and divide by the number of benefitting parcels in the district. Since the reserve fund balance is sufficient to ensure continued services, the BCI is not reflected in this year’s levy.

The Stanislaus County Auditor-Controller’s Office, Property Taxes and Assessments Division, collects a $0.20 fee per assessment and per parcel. This fee is directly assessed by Stanislaus County and is assessed in addition to the annual assessment being levied for LMAD No. 2.

COMMITTEE RECOMMENDATION:

This item is not required to be reviewed by Council Committee because it is the approval of the annual levy as directed by the City Council through the approval of the Resolution of Intention on June 2, 2026.

RECOMMENDED COUNCIL ACTION:

Staff Recommendations:

Resolution ordering the levy and collection of such charges as shown within the Engineer’s Annual Report within Landscape Maintenance Assessment District No. 2 for #18..
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City Council, June 23, 2026
Fiscal Year 2026-27 Annual Assessment for Landscape Maintenance Assessment District No. 2

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Dry Creek Meadows Subdivisions Nos. 7-10, Creekwood Meadows Subdivision and Yosemite Meadows Subdivisions Units 1 and 2 for Fiscal Year 2026-27.

Approved by:

Jessica Hill, Director of Community
and Economic Development
Joseph P. Lopez, City Manager
Attachments:

1. Resolution

2. LMAD No. 2 Boundary Map

3. LMAD No. 2 2026-27 Engineer’s Annual Report
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MODESTO CITY COUNCIL
RESOLUTION NO. 2026-XX

RESOLUTION ORDERING THE LEVY AND COLLECTION OF SUCH
CHARGES AS SHOWN WITHING THE ENGINEER’S ANNUAL REPORT
WITHIN LANDSCAPE MAINTENANCE ASSESSMENT DISTRICT NO. 2 FOR DRY CREEK MEADOWS SUBDIVISIONS NOS. 7-10, CREEKWOOD

MEADOWS SUBDIVISION AND YOSEMITE MEADOWS SUBDIVISIONS
UNITS 1 AND 2 FOR FISCAL YEAR 2026-27
WHEREAS, on June 2, 2026, by Resolution No. 2026-173 Council declared its intent to levy charges or assessment for the purpose of administering the maintenance of landscaping in the public right-of-way within the street medians and adjacent to the access control walls in Dry Creek Meadows Subdivisions Nos. 7-10, Creekwood Meadows Subdivision, and Yosemite Meadows Subdivision Units 1 and 2 under the provisions of the California Streets and Highways Code Sections 22500 through 22679, more commonly known as the Landscape and Lighting Act of 1972; and
WHEREAS, the charges against the real property are not levied with regard to property values but rather by the allocated cost shown within the Engineer’s Annual Report; and
WHEREAS, the annual assessment is to adjust annually, if necessary, according to the BCI for the San Francisco Bay Area as reported in the Engineering News Record the second week of February; and WHEREAS, the increase in the annual assessment is less than or equal to the annual inflator previously approved by the property owners within the District; and
WHEREAS, the annual adjustment for Fiscal Year 2026-27 is 1.80208%; #18..
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and
WHEREAS, the inflationary adjustment is applied when the district has minimal or negative fund reserves to offset the total cost estimates for the upcoming fiscal year; and
WHEREAS, the annual assessment for Fiscal Year 2026-27 is $34,820.85, while its projected expenses are $50,405.00; and WHEREAS, the levy for Fiscal Year 2024-25 was $34,204.54 and the projected expenses are $46,635.30; and
WHEREAS, any additional revenue stays within the LMAD No. 2 fund balance and will cover any unanticipated expense that occurs for LMAD No. 2; and
WHEREAS, a public hearing was held on June 23, 2026; and WHEREAS, the City of Modesto has determined and certified that the charges are either exempt from or in compliance with all the provisions of Proposition 218, which was passed by the voters in November 1996; and WHEREAS, City of Modesto has further determined the charges are in compliance with all the laws pertaining to the levy of such charges.

NOW, THEREFORE, BE IT RESOLVED by the Council of the City of Modesto that it hereby orders the levy and collection of such charges as shown within the Engineer’s Annual Report within Landscape Maintenance Assessment District No. 2 for Dry Creek Meadows Subdivisions Nos. 7-10, Creekwood Meadows Subdivision and Yosemite Meadows Subdivisions Units 1 and 2 for Fiscal Year 2026-27.

BE IT FURTHER RESOLVED that a certified copy of this resolution and #18..
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attached documentation shall be delivered to the Auditor-Controller of the County of Stanislaus for placement of such charges on the 2026-27 County Tax Roll, and in each subsequent fiscal year in which the charges may validly be levied.

BE IT FURTHER RESOLVED that the diagram of said assessment district, which is attached hereto, and amount of levy thereon is hereby confirmed. #18..
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The foregoing resolution was introduced at a regular meeting of the Council of the City of Modesto held on the 23rd day of June, 2026, by Councilmember _____, who moved its adoption, which motion being duly seconded by Councilmember ______, was upon roll call carried and the resolution adopted by the following vote:

AYES: Councilmembers:

NOES: Councilmembers:

ABSENT: Councilmembers:

ATTEST: _____________________________
DIANE NAYARES-PEREZ, City Clerk
(SEAL)
APPROVED AS TO FORM:

BY: ______________________________
JOSE M. SANCHEZ, City Attorney
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CITY OF MODESTO

COUNCIL AGENDA REPORT
DATE OF MEETING:

June 23, 2026
Date: May 7, 2026
TO: Mayor and City Council
THROUGH: Joseph P. Lopez, City Manager
FROM: Jessica Hill, Director of Community and Economic Development SUBJECT: Fiscal Year 2026-27 Annual Assessment for Shackelford Landscape and Lighting District
CONTACT: Edgar Garcia, Community Development Manager
[email protected], 209-577-5211
DESCRIPTION:

Hearing to consider approving Fiscal Year 2026-27 Diagram and Annual Assessment and ordering the Levy and Collection of Charges within Shackelford Landscape and Lighting District. (Funding: Shackelford Landscape and Lighting District) STRATEGIC PLAN ELEMENT:

BACKGROUND:

The Shackelford Landscape and Lighting District (Shackelford LLD) was formed by Stanislaus County on June 29,1999 in accordance with the Streets and Highways Code Sections 22500 through 22679, more commonly known as the Landscape and Lighting Act of 19721 (the Act). Shackelford LLD provides funding for the maintenance and service of seventy-seven (77) 200-watt high-pressure sodium streetlights located within its boundaries. On April 24, 2012, by Resolution No. 2012-142, Council approved the jurisdictional transfer of Shackelford LLD from Stanislaus County to the City. The City assumed full responsibility of Shackelford LLD on July 1, 2012. The annual assessment 1 Landscape and Lighting Act of 1972
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City Council, June 23, 2026
Fiscal Year 2026-27 Annual Assessment for Shackelford Landscape and Lighting District

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levied is calculated by dividing the total cost estimate by the total number of parcels within the Shackelford LLD. A copy of the boundary map is provided as Attachment 2.

Section 226202 et. seq. of the Act requires the legislative body (the City Council) to take the following actions prior to August 10th of each year:

2. Adopt a resolution approving the Engineer’s Annual Report as submitted or as modified by the City Council. This action was taken by Council on June 2, 2026, by Resolution 2026-174

3. Adopt a resolution of intention to levy and collect assessments within Shackleford LLD for the fiscal year. This action was taken by Council on June 2, 2026, by Resolution 2026-174

4. Conduct a public hearing.

5. Adopt a resolution confirming the diagram and assessment as originally proposed or as changed by the legislative body.

DISCUSSION:

All costs for Shackleford LLD are paid by the assessments levied on each property within the assessment area.

Expenses include maintenance of and utility bills for seventy-seven (77) streetlights as well as City staff time. It is expected that all expenses for Shackelford LLD will be paid by the assessments levied on properties within Shackelford LLD.

Each year the annual assessment uses a standard formula to calculate its fees:
estimated operation and maintenance costs for the current year minus the fund balance from the previous year and estimated property tax revenue for current year plus number of benefiting parcels in the district. There are 494 parcels within the district with four (4) owned by Modesto City Schools and three (3) owned by the City of Modesto. Pursuant to California Streets and Highways Code Section 226633, these seven (7) parcels will not be levied for Fiscal Year 2026-27. The total number of parcels to be levied for Fiscal Year 2026-27 is 487.

On March 3, 2026, by Resolution No. 2026-58, the Council directed staff to prepare and file the Fiscal Year 2026-27 Engineer’s Annual Report for the City of Modesto Shackelford Lighting and Landscape District.
2 Section 22620 et. seq. of the Landscape and Lighting Act of 1972 3 CA Streets and Highways Code Section 22663
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City Council, June 23, 2026
Fiscal Year 2026-27 Annual Assessment for Shackelford Landscape and Lighting District

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FISCAL IMPACT:

In Fiscal Year 2025-26, the total assessment levied was $17,785.24, while its projected expenses were $35,720.00. Expenses include maintenance of and utility bills for seventy-seven streetlights as well as City staff time. Each year levies are based on the current fiscal year expenses including the estimated expenses for the remaining fiscal year, adding $1.50 Administration Charge to the per parcel assessment amount and multiplying the per assessment amount to arrive at the total assessment amount.

The projected expenses for Fiscal Year 2026-27 are $30,182.00. The proposed annual assessment for Fiscal Year 2026-27 is $17,785.24. Due to the fund balance carried over from the previous fiscal year, the proposed annual assessment for Fiscal Year 2026–27 will remain unchanged at $17,785.24. The per parcel fee from Fiscal Year 2025-26 will remain unchanged for Fiscal Year 2026-27 (487 parcels at $36.52 per parcel).

COMMITTEE RECOMMENDATION:

This item is the approval of the annual levy as directed by the City Council through the approval of the Resolution of Intention on June 2, 2026.

RECOMMENDED COUNCIL ACTION:

Staff Recommendations:

Resolution ordering the levy and collection of such charges as shown within the Engineer’s Annual Report within the Shackelford Landscape and Lighting District for Fiscal Year 2026-27.

Approved by:

Jessica Hill, Director of Community
and Economic Development
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Fiscal Year 2026-27 Annual Assessment for Shackelford Landscape and Lighting District

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Joseph P. Lopez, City Manager
Attachments:

1. Resolution

2. Shackelford LLD Boundary Map

3. Shackelford LLD 2026-27 Engineer’s Annual Report
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MODESTO CITY COUNCIL
RESOLUTION NO. 2026-XX

RESOLUTION ORDERING THE LEVY AND COLLECTION OF SUCH
CHARGES AS SHOWN WITHIN THE ENGINEER’S ANNUAL REPORT WITHIN

THE SHACKELFORD LANDSCAPE AND LIGHTING DISTRICT FOR FISCAL YEAR 2026-27
WHEREAS, on June 2, 2026, by Resolution No. 2026-174, Council declared its intent to levy charges or assessment for the purpose of administering the maintenance of seventy-seven 200-watt high pressure sodium streetlights in the Shackelford Landscape and Lighting District under the provisions of California Streets and Highways Code Sections 22500 through 22679, more commonly known as Landscape and Lighting Act of 1972; and
WHEREAS, each year the annual assessment uses a standard formula to calculate its fees: estimated operation and maintenance costs for the current year minus the fund balance from the previous year and estimated property tax revenue for current year plus number of benefiting parcels in the district and $1.50 parcel administrative charge; and
WHEREAS, the annual assessment for Fiscal Year 2025-26 was $17,785.24 and the levy will remain the same at $17,785.24 in Fiscal Year 2026- 27, based on the previously mentioned standard formula with variances in projected expenditures covered by the current fund balance; and WHEREAS, the annual assessment will be $36.52 per parcel for Fiscal Year 2026-27, which is unchanged from Fiscal Year 2025-26; and WHEREAS, a public hearing was held on June 23, 2026.

NOW, THEREFORE, BE IT RESOLVED by the Council of the City of #19..
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Modesto that is hereby orders the levy and collection of such charges as shown withing the Engineer’s Annual Report within the Shackelford Landscape and Lighting District for Fiscal Year 2026-27.

BE IT FURTHER RESOLVED that a certified copy of this resolution and attached documentation shall be delivered to the Auditor-Controller of the County of Stanislaus for placement of such charges on the 2026-27 County Tax Roll.

BE IT FURTHER RESOLVED that the diagram of said assessment district, which is attached hereto, and amount of levy thereon is hereby confirmed.

The foregoing resolution was introduced at a regular meeting of the Council of the City of Modesto held on the 23rd day of June, 2026, by Councilmember _____, who moved its adoption, which motion being duly seconded by Councilmember ______, was upon roll call carried and the resolution adopted by the following vote:

AYES: Councilmembers:

NOES: Councilmembers:

ABSENT: Councilmembers:

ATTEST: _____________________________
DIANE NAYARES-PEREZ, City Clerk
(SEAL)
APPROVED AS TO FORM:

BY: ______________________________
JOSE M. SANCHEZ, City Attorney
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CITY OF MODESTO

COUNCIL AGENDA REPORT
DATE OF MEETING:

June 23, 2026
Date: May 30, 2026
TO: Mayor and City Council
THROUGH: Joseph P. Lopez, City Manager
FROM: William Wong, Director of Utilities
SUBJECT: Adopt Draft 2025 Joint Urban Water Management Plan and Water Shortage Contingency Plan Update
CONTACT: Miguel Alvarez, Associate Civil Engineer
[email protected], 209-577-5348
DESCRIPTION:

Hearing to consider adopting the Draft 2025 Joint Urban Water Management Plan and Water Shortage Contingency Plan Update. (Funding Source: Water Fund) STRATEGIC PLAN ELEMENT:

The recommended action supports the 2025-2026 City of Modesto Strategic Plan Initiatives, Goal D: Provide safe, efficient, and reliable infrastructure through proactive community investment, maintenance, and sustainability efforts.

BACKGROUND:

The Urban Water Management Planning Act of the California Water Code requires municipal water suppliers, providing drinking water to more than 3,000 customers, or supplying more than 3,000 acre-feet of water annually, to prepare and adopt an Urban Water Management Plan (UWMP) every five years. The City’s UWMP is required to define current and future water demands, types of uses, supply sources, supply reliability and resiliency, and include a Water Shortage Contingency Plan (WSCP). An UWMP also serves as a foundational document supporting water supply assessments, local and regional planning efforts, and the City’s General Plan updates.

The City has filed a UWMP with the Department of Water Resources (DWR) every five (5) years beginning in 1985. As a wholesale water supplier to the City of Modesto, the Modesto Irrigation District (MID) is also required to submit a UWMP. To simplify the #20..
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City Council, June 23, 2026
Adopt Draft 2025 Joint Urban Water Management Plan and
Water Shortage Contingency Plan Update

Page 2 of 3 ends

required efforts and coordinate urban water needs more closely, the City and MID have submitted a joint UWMP since 1995.

On June 8, 2021, by Resolution No. 2021-219, Council approved the Draft 2020 Joint UWMP and instructed staff to submit the Final 2020 Joint UWMP to DWR by July 1, 2021.

On June 8, 2021, by Resolution No. 2021-220, Council approved the WSCP Update and instructed staff to submit the WSCP Update as part of the Final 2020 Joint UWMP to DWR by July 1, 2021.

On October 14, 2025, by Resolution No. 2025-375, Council approved an Engineering Services Agreement with West Yost Associates for the preparation of the 2025 Joint UWMP and Water Conservation Plan Update.

On October 14, 2025, by Resolution No. 2025-376, Council approved entering into a Cost-Share Agreement with MID regarding the reimbursement of costs related to the preparation of the 2025 Joint UWMP.

DISCUSSION:

The Draft 2025 Joint UWMP was made available for public review beginning on May 25, 2026 to meet the minimum public review period as required by the California Water Code.

Notices were published in the Modesto Bee on Sunday, May 24th and Sunday, May 31st directing interested parties to the following page of the City’s website for access to the document:
https://modestogov.com/860/Urban-Water-Management-Plan
The notices also included the dates for both agencies public hearings to adopt the Draft 2025 Joint UWMP:

City of Modesto Tuesday, June 23, 2026
Modesto Irrigation District Tuesday, June 9, 2026
A notice of the public review period was also posted at Modesto City Hall.

Following Council adoption of the Draft 2025 Joint UWMP and WSCP Update, staff will address any comments received through the public review period and submit the Final 2025 Joint UWMP to DWR prior to the July 1, 2026 deadline.

FISCAL IMPACT:

There is no direct fiscal impact associated with adopting the 2025 Joint UWMP. #20..
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City Council, June 23, 2026
Adopt Draft 2025 Joint Urban Water Management Plan and
Water Shortage Contingency Plan Update

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COMMITTEE RECOMMENDATION
An Engineering Services Agreement with West Yost Associates for the preparation of the 2025 Joint UWMP and Water Conservation Plan Update was considered by the Finance Committee at the meeting held on September 22, 2025, where it was recommended that it be forwarded to Council.

CEQA/NEPA REQUIREMENTS:

This item does not constitute a project within the meaning of California Environmental Quality Act Guidelines Section 15378 and requires no environmental review.

RECOMMENDED COUNCIL ACTION:

Staff Recommendations:

Resolution adopting the Draft 2025 Joint Urban Water Management Plan and instructing staff to submit the Final 2025 Joint Urban Water Management Plan to the Department of Water Resources by July 1, 2026.

Resolution adopting the 2025 Water Shortage Contingency Plan and instructing staff to submit the 2025 Water Shortage Contingency Plan as part of the Final 2025 Joint Urban Water Management Plan to the Department of Water Resources by July 1, 2026.

Approved by:

William Wong, Director of Utilities
Joseph P. Lopez, City Manager
Attachments:

1. Resolutions (2)

2. Draft 2025 Joint Urban Water Management Plan
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06/23/2026/Utilities/MAlvarez/Item XX 1 2026-XX

MODESTO CITY COUNCIL
RESOLUTION NO. 2026-XX
RESOLUTION ADOPTING THE DRAFT 2025 JOINT URBAN WATER

MANAGEMENT PLAN AND INSTRUCTING STAFF TO SUBMIT THE FINAL 2025 JOINT URBAN WATER MANAGEMENT PLAN TO THE DEPARTMENT OF WATER RESOURCES BY JULY 1, 2026
WHEREAS, the Urban Water Management Planning Act of the California Water Code requires municipal water suppliers, providing drinking water to more than 3,000 customers, or supplying more than 3,000 acre-feet of water annually, to prepare and adopt an Urban Water Management Plan (UWMP) every five years; and
WHEREAS, the City’s UWMP is required to define current and future water demands, types of uses, supply sources, supply reliability and resiliency, and include a Water Shortage Contingency Plan (WSCP); and WHEREAS, an UWMP also serves as a foundational document supporting water supply assessments, local and regional planning efforts, and the City’s General Plan updates; and
WHEREAS, the City has filed an UWMP with the Department of Water Resources (DWR) every five years beginning in 1985; and WHEREAS, as a wholesale water supplier to the City of Modesto, the Modesto Irrigation District (MID) is also required to submit an UWMP; and WHEREAS, to simplify the required efforts and coordinate urban water needs more closely, the City and MID have submitted a joint UWMP since 1995; and
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WHEREAS, on October 14, 2025, by Resolution No. 2025-375, Council approved an Engineering Services Agreement with West Yost Associates for the preparation of the 2025 Joint UWMP and Water Conservation Plan Update; and WHEREAS, on October 14, 2025, by Resolution No. 2025-376, Council approved entering into a Cost-Share Agreement with MID regarding the reimbursement of costs related to the preparation of the 2025 Joint UWMP; and WHEREAS, the Draft 2025 Joint UWMP was made available for public review beginning on May 25, 2025 to meet the minimum public review period as required by the California Water Code; and
WHEREAS, on June 23, 2026, the City held a Public Hearing to adopt the Draft 2025 Joint UWMP.

NOW, THEREFORE, BE IT RESOLVED by the Council of the City of Modesto that it hereby adopts the Draft 2025 Joint UWMP and instructs staff to submit the Final 2025 Joint UWMP to DWR by July 1, 2026. #20..
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06/23/2026/Utilities/MAlvarez/Item XX 3 2026-XX
The foregoing resolution was introduced at a regular meeting of the Council of the City of Modesto held on the 23rd day of June, 2026, by Councilmember_______________, who moved its adoption, which motion being duly seconded by Councilmember _______________, was upon roll call carried and the resolution adopted by the following vote:

AYES: Councilmembers:

NOES: Councilmembers:

ABSENT: Councilmembers:

ATTEST: _____________________________

DIANE NAYARES-PEREZ, CMC,
City Clerk
(SEAL)
APPROVED AS TO FORM:

BY: ________________________________
JOSE M. SANCHEZ, City Attorney
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06/23/2026/Utilities/MAlvarez/Item XX 1 2026-XX

MODESTO CITY COUNCIL
RESOLUTION NO. 2026-XX
RESOLUTION ADOPTING THE 2025 WATER SHORTAGE CONTINGENCY PLAN AND INSTRUCTING STAFF TO SUBMIT THE 2025 WATER
SHORTAGE CONTINGENCY PLAN AS PART OF THE FINAL 2025 JOINT

URBAN WATER MANAGEMENT PLAN TO THE DEPARTMENT OF WATER
RESOURCES BY JULY 1, 2026
WHEREAS, the Urban Water Management Planning Act of the California Water Code requires municipal water suppliers, providing drinking water to more than 3,000 customers, or supplying more than 3,000 acre-feet of water annually, to prepare and adopt an Urban Water Management Plan (UWMP) every five years; and
WHEREAS, the City’s UWMP is required to define current and future water demands, types of uses, supply sources, supply reliability and resiliency, and include a Water Shortage Contingency Plan (WSCP); and WHEREAS, on October 14, 2025, by Resolution No. 2025-375, Council approved an Engineering Services Agreement with West Yost Associates for the preparation of the 2025 Joint UWMP and Water Conservation Plan Update; and WHEREAS, the 2025 WSCP consists of six Response Stages correlating to Estimated Water Shortage Ranges and their associated Response Actions; and
WHEREAS, adopting the WSCP as a part of the 2025 Final Joint UWMP and independently of, allows for revisions to be made to the WSCP without requiring the readoption of the full Joint UWMP; and
WHEREAS, on June 23, 2026, the City held a Public Hearing to adopt the Draft 2025 Joint UWMP and the 2025 WSCP; and
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NOW, THEREFORE, BE IT RESOLVED by the Council of the City of Modesto that it hereby adopts the 2025 WSCP and instructs staff to submit the 2025 WSCP as part of the Final 2025 Joint UWMP to the Department of Water Resources by July 1, 2026.

The foregoing resolution was introduced at a regular meeting of the Council of the City of Modesto held on the 23rd day of June, 2026, by Councilmember _______________, who moved its adoption, which motion being duly seconded by Councilmember _______________, was upon roll call carried and the resolution adopted by the following vote:

AYES: Councilmembers:

NOES: Councilmembers:

ABSENT: Councilmembers:

ATTEST: _____________________________

DIANE NAYARES-PEREZ, CMC,
City Clerk
(SEAL)
APPROVED AS TO FORM:

BY: ________________________________
JOSE M. SANCHEZ, City Attorney
#20..
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CITY OF MODESTO | MODESTO IRRIGATION DISTRICT
MAY
2026

PREPARED BY

PUBLIC DRAFT
2025 JOINT URBAN WATER

MANAGEMENT PLAN
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PUBLIC DRAFT REPORT | MAY 2026
EARYEAR2020
Joint 2025 Urban Water Management Plan
Prepared for
City of Modesto
and
Modesto Irrigation District
Project No. 418-60-25-02

Project Manager: Roberto Vera, PE, RCE #83500 Date

QA/QC Review: Elizabeth Drayer, PE, RCE #46872 Date
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May 2026
Table of Contents
EXECUTIVE SUMMARY .................................................................................................................. ES-1 Introduction....................................................................................................................................... ES-1 California Water Code Requirements ............................................................................................... ES-1 City and MID Water Systems............................................................................................................. ES-2 Water Use by City Customers............................................................................................................ ES-2 City and MID Water Supplies............................................................................................................. ES-2 Conservation Target Compliance ...................................................................................................... ES-3 City and MID Water Service Reliability.............................................................................................. ES-3 Water Shortage Contingency Plan .................................................................................................... ES-3 UWMP Preparation, Review, and Adoption...................................................................................... ES-3 CHAPTER 1 Introduction..................................................................................................................1-1

1.1 Introduction...................................................................................................................................1-1

1.2 Importance and Extent of City’s Water Management Planning Efforts........................................1-1

1.3 Changes from 2020 UWMP ...........................................................................................................1-1

1.4 Plan Organization ..........................................................................................................................1-2 CHAPTER 2 Plan Preparation ...........................................................................................................2-1

2.1 Basis for Preparing a Plan..............................................................................................................2-1

2.2 Regional Planning ..........................................................................................................................2-2

2.3 Individual or Regional Planning and Compliance ..........................................................................2-2

2.4 Fiscal or Calendar Year and Units of Measure ..............................................................................2-3

2.5 Coordination and Outreach...........................................................................................................2-4

2.5.1 Wholesale and Retail Coordination .....................................................................................2-4

2.5.2 Coordination with Other Agencies and the Community .....................................................2-5

2.5.3 Notice to Cities and Counties...............................................................................................2-5 CHAPTER 3 Service Area Description................................................................................................3-1

3.1 General Description.......................................................................................................................3-1

3.2 Service Area Description ...............................................................................................................3-1

3.2.1 Geographical Boundaries.....................................................................................................3-1

3.2.1.1 City Service Area.........................................................................................................3-1

3.2.1.2 MID Service Area ........................................................................................................3-1

3.2.2 Water Supply Overview .......................................................................................................3-1

3.2.3 Water System Facilities........................................................................................................3-2

3.2.3.1 Surface Water Supply .................................................................................................3-2

3.2.3.2 Groundwater Supply ..................................................................................................3-5

3.2.3.3 Distribution System....................................................................................................3-5 #20..
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3.3 Service Area Climate......................................................................................................................3-7

3.3.1 Historical Climate.................................................................................................................3-7

3.3.2 Potential Effects of Climate Change ....................................................................................3-8

3.4 Service Area Population and Demographics.................................................................................3-8

3.4.1 City of Modesto Water Service Area Population.................................................................3-8

3.4.2 MID Population..................................................................................................................3-10

3.4.3 Other Social, Economic, and Demographic Factors...........................................................3-10

3.5 Land Uses within Service Area.....................................................................................................3-11

3.5.1 Existing Land Uses within Service Area..............................................................................3-11

3.5.2 Future Land Uses within Service Area ...............................................................................3-11 CHAPTER 4 Water Use Characterization...........................................................................................4-1

4.1 Non-Potable Versus Potable Water Use .......................................................................................4-1

4.2 Water Use by Sector......................................................................................................................4-1

4.2.1 Historical Potable Water Use...............................................................................................4-2

4.2.1.1 City of Modesto..........................................................................................................4-2

4.2.1.2 MID.............................................................................................................................4-3

4.2.2 Current Water Use...............................................................................................................4-3

4.2.2.1 City of Modesto..........................................................................................................4-3

4.2.2.2 MID.............................................................................................................................4-4

4.2.3 Projected Water Use............................................................................................................4-5

4.2.3.1 City of Modesto..........................................................................................................4-5

4.2.3.2 MID.............................................................................................................................4-7

4.2.4 Characteristic Five-Year Water Use .....................................................................................4-8

4.2.4.1 City of Modesto..........................................................................................................4-8

4.2.4.2 MID.............................................................................................................................4-8

4.2.5 Estimating Future Water Savings.........................................................................................4-9

4.2.6 Water Use for Lower Income Households...........................................................................4-9

4.3 Distribution System Water Losses...............................................................................................4-10

4.3.1 Water Loss Audits..............................................................................................................4-10

4.3.2 Water Loss Standards ........................................................................................................4-12

4.4 Climate Change Considerations...................................................................................................4-14 CHAPTER 5 SB X7-7 Baselines, Targets, and 2020 Compliance...........................................................5-1

5.1 Overview and Background ............................................................................................................5-1

5.2 2020 Daily Per Capita Water Use Compliance ..............................................................................5-1

5.3 Regional Alliance ...........................................................................................................................5-2 CHAPTER 6 Normal-Year Water Supply Characterization ..................................................................6-1

6.1 Overview of Water Supplies..........................................................................................................6-1

6.2 Surface Water................................................................................................................................6-1

6.2.1 Surface Water Supply for MID.............................................................................................6-2

6.2.2 Modesto Regional Water Treatment Plant..........................................................................6-2 #20..
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6.3 Purchased or Imported Water.......................................................................................................6-3

6.3.1 Treatment and Delivery Agreement....................................................................................6-3

6.3.2 Amended and Restated Treatment and Delivery Agreement .............................................6-3

6.3.2.1 Surface Water Allocation............................................................................................6-4

6.4 Groundwater.................................................................................................................................6-5

6.4.1 Groundwater Supply for the City.........................................................................................6-5

6.4.1.1 Groundwater Basin Description .................................................................................6-5

6.4.1.2 Groundwater Level Trends.........................................................................................6-9

6.4.1.3 Groundwater Quality..................................................................................................6-9

6.4.1.4 Groundwater Management .....................................................................................6-10

6.4.1.5 Groundwater Management Actions.........................................................................6-12

6.4.1.6 Preliminary Operational Yield Estimate ...................................................................6-12

6.4.1.7 Historical Groundwater Pumping.............................................................................6-13

6.4.1.8 Projected Groundwater Use.....................................................................................6-14

6.4.2 Groundwater Supply for MID.............................................................................................6-15

6.5 Stormwater..................................................................................................................................6-16

6.6 Wastewater and Recycled Water................................................................................................6-17

6.6.1 Recycled Water Coordination............................................................................................6-17

6.6.2 Wastewater Collection, Treatment, and Disposal .............................................................6-17

6.6.2.1 Wastewater Collected and Treated by the City .......................................................6-18

6.6.2.2 Wastewater Collected and Treated by Other Agencies...........................................6-18

6.6.2.3 Wastewater in MID ..................................................................................................6-22

6.6.3 Recycled Water System .....................................................................................................6-22

6.6.4 Current and Potential Future Recycled Water Uses..........................................................6-22

6.6.4.1 Potential Future Recycled Water Uses.....................................................................6-24

6.6.4.1.1 Environmental Use..........................................................................................6-24

6.6.4.1.2 Groundwater Recharge...................................................................................6-24

6.6.5 Actions to Expand Future Recycled Water Use .................................................................6-25

6.7 Desalinated Water.......................................................................................................................6-25

6.8 Exchanges or Transfers................................................................................................................6-26

6.9 Future Water Projects.................................................................................................................6-26

6.9.1 Future Surface Water Supply Options...............................................................................6-27

6.9.2 Future Groundwater Supply Considerations.....................................................................6-28

6.9.2.1 Groundwater Well Capital Improvements...............................................................6-28

6.9.2.2 Potential Aquifer Storage and Recovery Program ...................................................6-28

6.9.2.3 Potential Managed Aquifer Recharge Program .......................................................6-29

6.10 Summary of Existing and Planned Sources of Water................................................................6-29

6.10.1 Existing and Planned Sources of Water for the City ........................................................6-29

6.10.2 Existing and Planned Sources of Water for MID..............................................................6-32

6.11 Climate Change Impacts to Supply............................................................................................6-34 #20..
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6.12 Energy Intensity.........................................................................................................................6-35

6.12.1 Water System Energy Intensity........................................................................................6-36

6.12.1.1 City Energy Use.......................................................................................................6-36

6.12.1.2 MID Energy Use......................................................................................................6-36

6.12.2 Wastewater System Energy Intensity..............................................................................6-36 CHAPTER 7 Water Service Reliability and Drought Risk Assessment..................................................7-1

7.1 Constraints on Water Sources.......................................................................................................7-1

7.1.1 MID Surface Water ..............................................................................................................7-1

7.1.1.1 Federal Energy Regulatory Commission Fish Flow Requirement...............................7-1

7.1.1.2 Tuolumne River Emergency Curtailment Orders .......................................................7-2

7.1.1.3 Bay-Delta Water Quality Control Plan........................................................................7-2

7.1.2 Groundwater........................................................................................................................7-3

7.2 Water Service Reliability Assessment............................................................................................7-3

7.2.1 Year Type Characterization..................................................................................................7-4

7.2.1.1 MID Surface Water.....................................................................................................7-4

7.2.1.2 Groundwater..............................................................................................................7-7

7.2.2 Water Service Reliability – Normal Year..............................................................................7-9

7.2.2.1 City of Modesto..........................................................................................................7-9

7.2.2.2 MID.............................................................................................................................7-9

7.2.3 Water Service Reliability – Single Dry Year........................................................................7-10

7.2.3.1 City of Modesto........................................................................................................7-10

7.2.3.2 MID...........................................................................................................................7-11

7.2.4 Water Service Reliability – Five Consecutive Year Drought...............................................7-12

7.2.4.1 City of Modesto........................................................................................................7-13

7.2.4.2 MID...........................................................................................................................7-14

7.3 Drought Risk Assessment ............................................................................................................7-15

7.3.1 Data, Methods, and Basis for Water Shortage Condition..................................................7-16

7.3.2 DRA Water Source Reliability.............................................................................................7-16

7.3.3 Total Water Supply and Use Comparison..........................................................................7-17

7.4 Water Management Tools and Options......................................................................................7-18

7.4.1 City of Modesto..................................................................................................................7-18

7.4.2 MID.....................................................................................................................................7-18 CHAPTER 8 Water Shortage Contingency Plan..................................................................................8-1

8.1 Background....................................................................................................................................8-1

8.2 City Water Shortage Contingency Plan .........................................................................................8-1

8.3 Water Supply Reliability Analysis..................................................................................................8-1

8.3.1 Seismic Risk Assessment and Mitigation Plan .....................................................................8-2

8.4 Adoption, Submittal, and Availability............................................................................................8-3 #20..
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CHAPTER 9 Demand Management Measures...................................................................................9-1

9.1 MID Water Conservation Program Overview................................................................................9-1

9.2 MID Demand Management Measures..........................................................................................9-1

9.2.1 Metering ..............................................................................................................................9-1

9.2.2 Public Education and Outreach............................................................................................9-1

9.2.3 Water Conservation Program Coordination and Staffing Support......................................9-2

9.2.4 Asset Management..............................................................................................................9-2

9.2.5 Wholesale Supplier Assistance Programs............................................................................9-2

9.2.6 Other Demand Management Measures..............................................................................9-2

9.3 City of Modesto Water Conservation Program Overview.............................................................9-3

9.4 City of Modesto Demand Management Measures.......................................................................9-3

9.4.1 Water Waste Prevention Ordinances..................................................................................9-4

9.4.1.1 DMM Description .......................................................................................................9-4

9.4.1.2 Implementation over the Past Five Years ..................................................................9-4

9.4.1.3 Plans for Continued Implementation.........................................................................9-4

9.4.2 Metering ..............................................................................................................................9-5

9.4.2.1 DMM Description .......................................................................................................9-5

9.4.2.2 Implementation over the Past Five Years ..................................................................9-5

9.4.2.3 Plans for Continued Implementation.........................................................................9-5

9.4.3 Conservation Pricing ............................................................................................................9-5

9.4.3.1 DMM Description .......................................................................................................9-5

9.4.3.2 Implementation over the Past Five Years ..................................................................9-5

9.4.3.3 Plans for Continued Implementation.........................................................................9-6

9.4.4 Public Education and Outreach............................................................................................9-6

9.4.4.1 DMM Description .......................................................................................................9-6

9.4.4.2 Implementation over the Past Five Years ..................................................................9-7

9.4.4.3 Plans for Continued Implementation.........................................................................9-7

9.4.5 Programs to Assess and Manage Distribution System Real Loss.........................................9-7

9.4.5.1 DMM Description .......................................................................................................9-7

9.4.5.2 Implementation over the Past Five Years ..................................................................9-8

9.4.5.3 Plans for Continued Implementation.........................................................................9-8

9.4.6 Water Conservation Program Coordination and Staffing Support......................................9-9

9.4.6.1 DMM Description .......................................................................................................9-9

9.4.6.2 Implementation over the Past Five Years ..................................................................9-9

9.4.6.3 Plans for Continued Implementation.........................................................................9-9

9.4.7 Other Demand Management Measures............................................................................9-10

9.4.7.1 Residential Conservation Programs .........................................................................9-10

9.4.7.1.1 DMM Description............................................................................................9-10

9.4.7.1.2 Implementation over the Past Five Years.......................................................9-11

9.4.7.1.3 Plans for Continued Implementation .............................................................9-11

9.4.7.2 Commercial, Industrial, Institutional Customer Conservation Programs ................9-11

9.4.7.2.1 DMM Description............................................................................................9-11

9.4.7.2.2 Implementation over the Past Five Years.......................................................9-11 #20..
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9.4.7.2.3 Plans for Continued Implementation .............................................................9-11

9.4.7.3 Large Landscape Irrigation Conservation Programs.................................................9-12

9.4.7.3.1 DMM Description............................................................................................9-12

9.4.7.3.2 Implementation over the Past Five Years.......................................................9-12

9.4.7.3.3 Plans for Continued Implementation .............................................................9-13

9.4.7.4 Rebate Programs......................................................................................................9-13

9.4.7.4.1 DMM Description............................................................................................9-13

9.4.7.4.2 Implementation over the Past Five Years.......................................................9-13

9.4.7.4.3 Plans for Continued Implementation .............................................................9-13

9.4.7.5 One Water Modesto Program..................................................................................9-14

9.5 Continued Implementation of DMMs.........................................................................................9-14

9.5.1 Meeting Urban Water Use Objectives...............................................................................9-14

9.5.2 Annual Water Use Reporting .............................................................................................9-15 CHAPTER 10 Plan Adoption, Submittal, and Implementation..........................................................10-1

10.1 Inclusion of All 2025 Data..........................................................................................................10-1

10.2 Notice of Public Hearing............................................................................................................10-1

10.2.1 Notices to Cities and Counties.........................................................................................10-1

10.2.2 Notice to the Public .........................................................................................................10-3

10.3 Public Hearing and Adoption.....................................................................................................10-3

10.3.1 Public Hearing ..................................................................................................................10-3

10.3.2 Adoption ..........................................................................................................................10-3

10.4 Plan Submittal ...........................................................................................................................10-3

10.5 Public Availability.......................................................................................................................10-4

10.6 Plan Implementation.................................................................................................................10-4

10.7 Amending an Adopted UWMP or Water Shortage Contingency Plan..........................................10-4

LIST OF TABLES
Table 2-1. Public Water Systems (DWR Table 2-1 Retail)....................................................................2-2 Table 2-2. Plan Identification (DWR Table 2-2)...................................................................................2-3 Table 2-3. Supplier Identification (DWR Table 2-3).............................................................................2-3 Table 2-4. Water Supplier Information Exchange (DWR Table 2-4 Retail)..........................................2-4 Table 2-5. Water Supplier Information Exchange (DWR Table 2-4 Wholesale)..................................2-4 Table 3-1. Monthly Average Climate Data Summary ..........................................................................3-7 Table 3-2. Population – Current and Projected (DWR Table 3-1 Retail) .............................................3-9 Table 3-3. Population – Current and Projected (DWR Table 3-1 Wholesale) ...................................3-10 Table 4-1. City’s Historical Potable Water Use by Sector....................................................................4-3 Table 4-2. MID’s Historical Wholesale Potable Water Use .................................................................4-3 #20..
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Table 4-3. Uses for Potable and Non-Potable Water in 2025 – Actual (DWR Table 4-1 Retail)..........4-4 Table 4-4. Uses for Potable and Non-Potable Water – Actual (DWR Table 4-1 Wholesale)...............4-5 Table 4-5. Uses for Potable and Non-Potable Water – Projected (DWR Table 4-2 Retail) .................4-6 Table 4-6. Uses for Potable and Raw Water – Projected (DWR Table 4-2 Wholesale).......................4-7 Table 4-7. City’s Projected Five-Year Potable Water Demands for Drought Risk Assessment...........4-8 Table 4-8. MID’s Projected Five-Year Wholesale Water Demands for Drought Risk Assessment......4-8 Table 4-9. Inclusion in Water Use Projections (DWR Table 4-3 Retail)...............................................4-9 Table 4-10. Water Loss Audit Reporting (DWR Table 4-5 Retail)......................................................4-11 Table 4-11. Progress Towards 2028 Water Loss Standard (DWR Table 4-6 Retail) ..........................4-13 Table 5-1. SB X7-7 2020 Target Progress (DWR Table 5-1) .................................................................5-2 Table 6-1. Groundwater Subbasin Characteristics and Service Areas.................................................6-6 Table 6-2. Groundwater Basin Prioritization for Sustainable Groundwater Management Act........6-11 Table 6-3. City of Modesto’s Preliminary Operational Yield Assumed for Each Subbasin................6-13 Table 6-4. Groundwater Volume Pumped (DWR Table 6-1 Retail)...................................................6-14 Table 6-5 Projected Groundwater Use for City of Modesto .............................................................6-15 Table 6-6 Groundwater Volume Pumped (DWR Table 6-1 Wholesale)............................................6-15 Table 6-7. Wastewater Collected Within Service Area in 2025 (DWR Table 6-2 Retail)...................6-20 Table 6-8. Wastewater Treatment and Discharge Within Service Area in 2025 (DWR Table 6-3 Retail)...................................................................................................6-21 Table 6-9. Wastewater Treatment and Outcomes Within Service Area in 2025 (DWR Table 6-3 Wholesale)...........................................................................................6-22 Table 6-10. Current and Projected Recycled Water Direct Beneficial Uses Within Service Area (DWR Table 6-4 Retail)...................................................................................................6-23 Table 6-11. 2020 Recycled Water Use Projection Compared to 2025 Actual (DWR Table 6-5 Retail)...................................................................................................6-23 Table 6-12. Current and Projected Recycled Water Direct Beneficial Uses Within Service Area (DWR Table 6-4 Wholesale)...........................................................................................6-23 Table 6-13. 2020 Recycled Water Use Projection Compared to 2025 Actual (DWR Table 6-5 Wholesale)...........................................................................................6-24 Table 6-14. Methods to Expand Future Recycled Water Use (DWR Table 6-6 Retail)......................6-25 Table 6-15. Expected Future Water Supply Projects or Programs (DWR Table 6-7 Retail) ..............6-27 Table 6-16. Expected Future Water Supply Projects or Programs (DWR Table 6-7 Wholesale).......6-27 Table 6-17. Water Supplies – Actual (DWR Table 6-8 Retail)............................................................6-30 Table 6-18. Water Supplies – Projected (DWR Table 6-9 Retail).......................................................6-31 Table 6-19. Water Supplies – Actual (DWR Table 6-8 Wholesale)....................................................6-32 #20..
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Table 6-20. Water Supplies – Projected (DWR Table 6-9 Wholesale)...............................................6-33 Table 6-21. Energy Intensity for the City – Total Utility Approach (DWR Table O-1B) .....................6-37 Table 6-22. Energy Intensity for MID – Total Utility Approach (DWR Table O-1B)...........................6-38 Table 6-23. Energy Intensity – Wastewater & Recycled Water (DWR Table O-2) ............................6-39 Table 7-1. Recent MID Water Allocations...........................................................................................7-6 Table 7-2. Basis of Water Year Data (Reliability Assessment) (DWR Table 7-1 Wholesale)................7-7 Table 7-3. Basis of Water Year Data (Reliability Assessment) (DWR Table 7-1 Retail) .......................7-8 Table 7-4. Normal Year Supply and Demand Comparison (DWR Table 7-2 Retail).............................7-9 Table 7-5. Normal Year Supply and Demand Comparison (DWR Table 7-2 Wholesale)...................7-10 Table 7-6. Single Dry Year Supply and Demand Comparison (DWR Table 7-3 Retail).......................7-11 Table 7-7. Single Dry Year Supply and Demand Comparison (DWR Table 7-3 Wholesale)...............7-12 Table 7-8. Multiple Dry Years Supply and Demand Comparison (DWR Table 7-4 Retail).................7-14 Table 7-9. Multiple Dry Years Supply and Demand Comparison (DWR Table 7-4 Wholesale).........7-15 Table 7-10. City’s Projected Water Supplies for Drought Risk Assessment......................................7-16 Table 7-11. Five-Year Drought Risk Assessment Tables to Address Water Code §10635(b) (DWR Table 7-5).............................................................................................................7-17 Table 9-1. City of Modesto Current Water Rates and Charges...........................................................9-6 Table 9-2. City of Modesto Rebate Programs from 2021 to 2025 ....................................................9-13 Table 10-1. Notification to Cities and Counties (DWR Table 10-1 Retail) .........................................10-2 Table 10-2. Notification to Cities and Counties (DWR Table 10-1 Wholesale) .................................10-2

LIST OF FIGURES
Figure 3-1. City of Modesto Water Service Areas...............................................................................3-3 Figure 3-2. MID Water Service Area....................................................................................................3-4 Figure 3-3. City of Modesto Existing Water System Facilities.............................................................3-6 Figure 6-1. City of Modesto Groundwater Subbasins.........................................................................6-7 Figure 9-1. Urban Water Use Objective Components.......................................................................9-15 #20..
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LIST OF APPENDICES
Appendix A: Urban Water Management Planning Act Legislative Requirements Appendix B: DWR 2025 Urban Water Management Plan Tables Appendix C: DWR 2025 Urban Water Management Plan Checklist Appendix D: Agency and Public Notices
Appendix E: Distribution System Water Loss Audits
Appendix F: Amended and Restated Treatment and Delivery Agreement Between Modesto Irrigation District and City of Modesto
Appendix G: Water Shortage Contingency Plan
Appendix H: Water Conservation Plan and Related Documents Appendix I: UWMP and WSCP Adoption Resolutions

LIST OF ACRONYMS AND ABBREVIATIONS
°F Degrees Fahrenheit 3-7
AB Assembly Bill 1-1
ACS American Community Survey 4-10
Act Urban Water Management Planning Act ES,1-1
AF Acre-Feet 2-1
AFY Acre-Feet Per Year 2-1
AMI Advanced Metering Infrastructure 4-8
AMR Automatic Meter Reading 9-10
ARTDA Amended and Restated Treatment and Delivery Agreement 3-5 ASR Aquifer Storage and Recovery 6-24
AWIA America’s Water Infrastructure Act 8-2
AWMP Agricultural Water Management Plan 1-1
AWWA American Water Works Association 9-9
bgs Below Ground Surface 6-7
BMP Best Management Practices 6-27
ccf Hundred Cubic Feet 9-7
CCR California Code of Regulations 4-12
CHAS Comprehensive Housing Affordability Strategy 4-10
CII Commercial, Industrial, Institutional 9-12
CIMIS California Irrigation Management Information System 3-8 City City of Modesto ES,1-1
County Stanislaus County 3-1
CVP Central Valley Project 6-13
CWC California Water Code 1-2
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CWP California Water Plan 6-27
DBCP Dibromochloropropane 6-8
DDW California Division of Drinking Water 6-8
DIM Dedicated Irrigation Meter 9-17
DMC Delta-Mendota Canal 6-13
DMM Demand Management Measure 9-1
DOF California Department of Finance 3-9
DPWD Del Puerto Water District 6-13
DRA Drought Risk Assessment 1-2
DWR California Department of Water Resources 1-3
DWR Guidebook Urban Water Management Plan Guidebook 2025 1-3 DWR Methodologies DWR Methodologies for Calculating Baseline and Compliance Urban Per Capita Water Use (2016)
5-1
EO Executive Order 9-5
ESIRWMP East Stanislaus Integrated Regional Water Management Plan 6-26 ESRWMP East Stanislaus Regional Water Management Partnership 6-26 ET Evapotranspiration 3-8
ETSGA East Turlock Subbasin GSA 6-10
EWMP Efficient Water Management Practice 9-1
FERC Federal Energy Regulatory Commission 7-2
ft msl Feet Above Mean Sea Level 6-7
GHG Greenhouse Gas 3-9
GIS Geographical Information Systems 9-10
GPCD Gallons Per Capita Per Day 4-5
GPS Global Positioning Systems 9-10
GSA Groundwater Sustainability Agency 1-1
GSP Groundwater Sustainability Plan 1-1
HUD Housing and Urban Development 4-10
IRWM Integrated Regional Water Management 6-28
Joint 2025 UWMP Joint 2025 Urban Water Management Plan ES,1-1 kWh Kilowatt-Hours 6-26
LHMP Local Hazard Mitigation Plan 8-1
M&I Municipal and Industrial 6-1
MAF Million Acre Feet 7-2
MCL Maximum Contaminant Level 6-8
MG Million Gallons 3-6
mg/L Milligrams Per Liter 6-2
MGD Million Gallons Per Day 6-1
MID, District Modesto Irrigation District ES, 1-1
MMC Modesto Municipal Code 8-1
MRWTP Modesto Regional Water Treatment Plant ES,3-5
MWELO Model Water Efficient Landscape Ordinance 9-14
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NAICS North American Industry Classification System 4-1 NPDES National Pollutant Discharge Elimination System 6-12 NVRRWP North Valley Regional Recycled Water Program 6-13 PCE Perchloroethylene 6-8
PEIR Program‑Level Environmental Impact Report 3-12
Project Domestic Water Project 9-3
PWS Public Water System
RMS Resource Management Strategies 6-25
RO Reverse Osmosis 6-19
RRA Risk and Resilience Assessment 8-2
RUWMP Regional Urban Water Management Plan 2-2
RWQCF Regional Water Quality Control Facility 6-15
SB Senate Bill 1-1
SB X7-7 Water Conservation Act of 2009 ES,1-1
SBA Strong Base Anion 6-24
SCADA Supervisory Control and Data Acquisition 6-3
SCP Salida Community Plan 3-12
sf Square Feet 9-14
SGMA Sustainable Groundwater Management Act 1-1
SOI Sphere of Influence 3-1
sq mi Square Mile 6-2
State Water Board State Water Resources Control Board 1-1 STRGBA Stanislaus and Tuolumne Rivers Groundwater Basin Association 6-10 SWRP Storm Water Resource Plan 6-13
TCE Trichloroethylene 6-8
TCP 1,2,3-Trichloropropane 6-8
TDA Treatment and Delivery Agreement 3-5
TDS Total Dissolved Solids 6-2
TID Turlock Irrigation District 6-2
TWPS Treated Water Pump Station 9-2
USGS United States Geological Survey 6-26
UV Ultraviolet 6-19
UWMP Urban Water Management Plan ES,1-1
UWUO Urban Water Use Objective 4-12
WMP Water Master Plan 3-9
WSCP Water Shortage Contingency Plan ES,1-2
WTSGSA West Turlock Subbasin GSA 6-10
WUE Water Use Efficiency 10-3
WWTP Wastewater Treatment Plant 3-1
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EXECUTIVE SUMMARY

INTRODUCTION
An Urban Water Management Plan (UWMP) helps water suppliers assess the availability of their water supplies to meet current and projected water demands to help ensure reliable water service under different conditions. Water supply planning is especially critical for California as climate change alters rainfall and snowfall patterns (impacting water supply availability) and development continues to occur statewide (increasing water demands and the need for reliable water supplies). The Urban Water Management Planning Act (Act) requires larger water suppliers that provide water to urban users (whether directly or indirectly) to develop UWMPs every five years. UWMPs evaluate conditions for the next 20 to 25 years, so these regular updates ensure continued, long-term water supply planning.

Modesto Irrigation District (MID) sells treated water to the City of Modesto (City), who then sells and distributes it to individual water users (customers) (e.g., residents and businesses). In this arrangement, MID is a water wholesaler and the City is a water retailer. Because the City provides water to more than 3,000 customers, both the City and MID are required to prepare a UWMP. For the 2025 UWMP, the City and MID have elected to prepare their plan jointly (Joint 2025 UWMP).

This Executive Summary serves as a Lay Description of the City and MID's Joint 2025 UWMP, as required by California Water Code §10630.5.

CALIFORNIA WATER CODE REQUIREMENTS
The California Water Code documents specific requirements for California water suppliers. The Act is included in the California Water Code and specifies the required elements of a UWMP, including discussing an agency’s water system and facilities, calculating how much water its customers use (i.e., water demand) and how much it can supply, and detailing how it would respond during a drought or other water supply shortage. Also, a UWMP must describe what specific coordination steps were taken to prepare, review, and adopt the plan.

The Act has been revised over the years. The Water Conservation Act of 2009 (also known as SB X7-7) required retail water agencies to establish water use targets for 2015 and 2020 that would result in statewide water savings of 20 percent by 2020. In their 2025 UWMPs, retail water agencies (i.e., those distributing water to end users like residences and businesses) are required to report on their compliance with SB X7-7 2020 water use targets.

The 2012 to 2016 drought led to further revisions to the Act to improve water supply planning for long-term reliability and resilience to drought and climate change. These revisions were formalized in the 2018 Water Conservation Legislation and include:
• Five Consecutive Dry-Year Water Reliability Assessment: Analyze water supply reliability for five consecutive dry years over the planning period of this plan (see Chapter 7). • Drought Risk Assessment: Assess water supply reliability for the next five years assuming they are dry years (see Chapter 7).
• Seismic Risk: Identify the seismic risk to the agency’s water facilities and have a plan to address identified risks (see Chapter 8).
• Energy Use Information: If data is available, include reporting on the amount of electricity used to obtain, treat, and distribute water (see Chapter 6). #20..
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• Water Shortage Contingency Plan (WSCP): Update the agency’s plan to include an annual process for assessing potential gaps between planned water supply and demands; conform with the State’s standard water shortage levels (including a shortage level greater than 50 percent) for consistent messaging and reporting; and provide water shortage responses that are locally appropriate (see Chapter 8).
• Lay Description: Provide a lay description of the findings of the UWMP; this Executive Summary serves as the “Lay Description” for this plan.

Major components and findings of the City and MID’s Joint 2025 UWMP are summarized below.

CITY AND MID WATER SYSTEMS
MID diverts water from the Tuolumne River (i.e., surface water) and treats it at the Modesto Regional Water Treatment Plant (MRWTP) before delivering it to the City. The MRWTP is owned and operated by MID, along with storage, pumping, and transmission pipeline facilities.

In addition to receiving treated surface water from MID, the City has facilities to produce drinking (i.e., potable) water by pumping from City-owned wells (groundwater) and treating it. The City also owns and operates storage reservoirs and an extensive network of pipelines and pumping facilities to deliver drinking water to its customers, which include residential and commercial customers in Modesto, Salida, portions of North Ceres, Empire, and other contiguous Stanislaus County areas. The City also serves Grayson, Del Rio, Ceres (Walnut Manor), and portions of Turlock.

WATER USE BY CITY CUSTOMERS
In 2025, the City’s total potable water demand was approximately 49,738 acre-feet (AF), including system losses. Water use varies by use type, with single-family residential and commercial water uses representing the largest components of the total water demand.

The City anticipates the potential for significant growth in the next 25 years, which would increase its demand for water. Thorough and accurate accounting of current and future water demands is critical for the City’s planning efforts. To continue delivering safe and reliable drinking water, the City must know how much water its customers currently use and how much they expect to use in the future.

Based on projected population growth and land use development, the City’s potable water demand could increase by approximately 29 percent (from 2025 demands) by 2050, to approximately 64,390 AF per year (AFY). MID’s urban water demand consists only of sales to the City and is projected to increase along with City demand in accordance with the City and MID’s treatment and delivery agreement (2005 ARTDA).

CITY AND MID WATER SUPPLIES
The City’s water supplies consist of purchases from MID (approximately 59 percent of potable supply in 2025) and groundwater pumped by the City (approximately 41 percent of potable supply in 2025). All of MID’s supply to the City is surface water from the Tuolumne River, which is mainly fed by snowmelt from the central Sierra Nevada.

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groundwater pumping. Because of this flexibility, the City’s future water supplies are expected to keep pace with its water demands. Neither the City nor MID have included new water supply projects in this plan.

CONSERVATION TARGET COMPLIANCE
Wholesale water suppliers like MID are not required to comply with conservation targets, so this section focuses on the City only. In its 2020 UWMP, the City verified that it achieved its 2020 water use target in accordance with SB X7-7. The City’s per capita water use in 2020 was 175 gallons per capita per day (GPCD), below the confirmed 2020 water use target of 228 GPCD. This was the result of continued water efficiency improvements by the City and conservation by its customers following the recent drought.

CITY AND MID WATER SERVICE RELIABILITY
The California Water Code asks agencies to evaluate their water service reliability by examining the impact of drought on their water supplies and comparing those reduced supplies to water demands. Specifically, agencies should calculate their water supplies during a single dry year and a five consecutive dry year period using historical records. For example, the City can estimate its supply during a single dry year by looking at how much treated surface water and groundwater was available during the driest year on record. If the historical “dry year” supply was reduced by 10 percent, then the City can conservatively assume a similar 10 percent reduction in its supplies during a future dry year.

The City and MID are well-positioned to withstand the effects of a single dry year and a five-year drought.

Drought risk was specifically assessed between 2026 and 2030, assuming that these are dry years. In general, during dry years MID reduces its treated surface water deliveries to the City, and the City increases its groundwater pumping so that total supplies (MID deliveries plus groundwater) are sufficient to meet demands. The City expects to have enough water supplies to meet water demands for a five-year drought beginning in 2026. This remains true for one-year and five-year droughts beginning in 2030, 2035, 2040, 2045, and 2050.

WATER SHORTAGE CONTINGENCY PLAN
A WSCP describes an agency’s plan for preparing for and responding to water shortages. Only the City’s WSCP is included in this Joint 2025 UWMP. Since MID is primarily an agricultural water supplier, its water shortage responses are included in its separate Agricultural Water Management Plan.

The City’s WSCP was adopted in 2021 to be consistent with the 2018 Water Conservation Legislation requirements. The City has made some minor updates to its WSCP with the preparation of this Joint 2025 UWMP to reflect improvements in water metering and the integration of recently completed City and County planning documents. The WSCP may be used for foreseeable and unforeseeable events and is adopted concurrently with this plan by separate resolution to allow for updates as conditions change.

UWMP PREPARATION, REVIEW, AND ADOPTION
The City and MID developed this Joint 2025 UWMP in coordination with the public. While preparing this plan, the City and MID also notified other stakeholders (Stanislaus County, City of Turlock, City of Ceres, etc.) of its preparation, its availability for review, and the public hearings prior to adoption. The City and MID encouraged community participation in the development of the Joint 2025 UWMP using newspaper advertisements and web-based communication. These public notices included the time and place of the public hearings, as well as where the plan would be available for public inspection. #20..
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The public hearings provided an opportunity for the City and MID’s water users and the general public to become familiar with the Joint 2025 UWMP and ask questions about the City and MID’s water supply, their continuing plans for providing a reliable, safe, high-quality water supply, and their plans to address potential water shortages. Following the public hearings, this Joint 2025 UWMP and WSCP were adopted by the Modesto City Council on MM DD, 2026, and by the MID Board of Directors on MM DD, 2026, at their respective meetings. A copy of the adopted UWMP was submitted to the Department of Water Resources and is available on the City and MID websites:
• City of Modesto Utilities Department: https://www.modestogov.com/860 • MID: https://www.mid.org/water/
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CHAPTER 1
Introduction
This chapter provides an introduction and overview of the City of Modesto (City) and Modesto Irrigation District (MID) 2025 Urban Water Management Plan (UWMP) including the importance and extent of the City and MID’s water management planning efforts, changes since the preparation of the Joint 2020 UWMP, and the organization of the Joint 2025 UWMP. This 2025 UWMP has been prepared jointly by City and MID staff and West Yost.

1.1 INTRODUCTION
The Urban Water Management Planning Act (Act) was originally established by Assembly Bill (AB) 797 on September 21, 1983. Passage of the Act was recognition by State legislators that water is a limited resource and a declaration that efficient water use and conservation would be actively pursued throughout the State. The primary objective of the Act is to direct “urban water suppliers” to develop a UWMP which provides a framework for long-term water supply planning, and documents how urban water suppliers are carrying out their long-term resource planning responsibilities to ensure adequate water supplies are available to meet existing and future water demands. A copy of the current version of the Act, as incorporated in §10608 and §10610 through §10656 of the California Water Code (CWC), is provided in Appendix A of this plan.

1.2 IMPORTANCE AND EXTENT OF CITY’S WATER MANAGEMENT PLANNING

EFFORTS
The purpose of the UWMP is to provide a planning tool for the City and MID for developing, managing, and delivering municipal water supplies to the City’s water service area. The City and MID have had a long history of providing reliable water supply to their customers. To continue to meet the water needs of the community, the City and MID carefully manage their available water resources. This plan provides the City and MID with a comprehensive water management action plan for guidance as water demand and/or water supply conditions change.

The Water Shortage Contingency Plan (WSCP) is part of this UWMP and provides a plan for response to various water supply shortage conditions.

It should be noted that MID is primarily an agricultural water supplier and has also prepared a 2025 Agricultural Water Management Plan (AWMP) Update in accordance with the requirements from the Water Conservation Act of 2009.

1.3 CHANGES FROM 2020 UWMP
The Urban Water Management Planning Act has been modified over the years in response to the State’s water shortages, droughts, and other factors. A significant amendment was made in 2009, after the 2007 to 2009 drought, and as a result of the Governor’s call for a statewide 20 percent reduction in urban water use by the year 2020. This was the Water Conservation Act of 2009, also known as Senate Bill Seven of the Senate’s Seventh Extraordinary Session of 2009 (SB X7-7). This Act required agencies to establish water use targets for 2020 that would result in statewide water savings of 20 percent by 2020. The City is required to report compliance with its 2020 water use target in its 2025 UWMP.

The 2012 to 2016 drought led to further amendments to the CWC to improve on water supply planning for long-term reliability and resilience to drought and climate change. The 2018 Water Conservation Regulation for Making Conservation a California Way of Life (AB 1668 [Friedman] and SB 606 [Hertzberg]) #20..
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required major additions and changes to the CWC. These changes are associated with managing drought preparedness and water shortage contingency planning for urban water suppliers.

No substantive changes to the requirements have been adopted since the completion of the City and MID’s Joint 2020 UWMP. This 2025 UWMP builds on the planning and reporting provided in the Joint 2020 UWMP. Key updates include:

1. Water Service Reliability Assessment – a water supply and demand assessment which compares the total water supply sources available to the City with the long-term total projected water use over the next 25 years (to 2050), in five-year increments, for a normal water year, a single dry water year, and a drought lasting five consecutive water years (CWC §10635(a))

2. Drought Risk Assessment – an assessment of the City’s water supply reliability assuming that the Years 2026 to 2030 will be the five dry consecutive years (CWC §10635(b))

3. Water Use Target Compliance – compliance with the City’s previously adopted 2020 per capita water use targets in accordance with SB X7-7 (Water Conservation Act of 2009, SB X7-7; CWC §10608.20)

4. Water Loss Quantification – a summary report quantifying the City’s system water loss for Years 2020 to 2024, and progress toward compliance with the City’s Water Loss Standard as established by the State Water Resources Control Board (State Water Board) (CWC §10631(d)(3)(c))

5. Groundwater Management Compliance – status update on Sustainable Groundwater Management Act (SGMA) compliance activities (i.e., status of Groundwater Sustainability Agency (GSA) activities and Groundwater Sustainability Plan (GSP) implementation) (CWC §10631(b)(4))
This UWMP also includes refinement and minor updates to the City’s WSCP to reflect improvements in water metering and the integration of recently completed City and County planning documents, including the Emergency Response Plan, Risk and Resilience Assessment, and Multi-Jurisdictional Hazard Mitigation Plan.

1.4 PLAN ORGANIZATION
This Joint 2025 UWMP contains the appropriate sections and tables required per CWC Division 6, Part 2.6 (Urban Water Management Planning Act), included in Appendix A of this 2025 UWMP, and has been prepared based on guidance provided by the California Department of Water Resources (DWR) in its 2025 Urban Water Management Plan Guidebook for Urban Water Suppliers (DWR Guidebook).

As described in this plan, the City currently receives treated surface water supplies from MID, and MID delivers treated surface water supplies exclusively to the City. Therefore, where applicable, separate descriptions have been included for the City and MID water systems. These sections reference each other extensively. Because this relationship is currently exclusive, much of the retail-wholesale information is interchangeable between these agencies. In addition, because MID does not have any direct urban customers, the City oversees demand management measures and other public outreach activities. #20..
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This Joint 2025 UWMP is organized into the following chapters:
• Chapter 1: Introduction
• Chapter 2: Plan Preparation
• Chapter 3: Service Area Description
• Chapter 4: Water Use Characterization
• Chapter 5: SB X7-7 Baselines, 2020 Targets, and 2025 Reporting • Chapter 6: Normal-Year Water Supply Characterization
• Chapter 7: Water Service Reliability and Drought Risk Assessment • Chapter 8: Water Shortage Contingency Plan
• Chapter 9: Demand Management Measures
• Chapter 10: Plan Adoption, Submittal, and Implementation This Joint 2025 UWMP also contains the following appendices of supplemental information and data related to the City and MID’s Joint 2025 UWMP:
• Appendix A: Urban Water Management Planning Act Legislative Requirements • Appendix B: DWR 2025 Urban Water Management Plan Tables • Appendix C: DWR 2025 Urban Water Management Plan Checklist • Appendix D: Agency and Public Notices
• Appendix E: Distribution System Water Loss Audits
• Appendix F: Amended and Restated Treatment and Delivery Agreement Between Modesto Irrigation District and City of Modesto
• Appendix G: Water Shortage Contingency Plan
• Appendix H: Water Conservation Plan and Related Documents • Appendix I: UWMP and WSCP Adoption Resolutions
Furthermore, this Joint 2025 UWMP contains all the tables recommended in the DWR Guidebook, both embedded into the UWMP chapters where appropriate and included in Appendix B.

DWR’s UWMP Checklist, as provided in the DWR Guidebook, has been completed by West Yost to demonstrate the plan’s compliance with applicable requirements. A copy of the completed checklist is included in Appendix C.
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CHAPTER 2
Plan Preparation
This chapter describes the preparation of the Joint 2025 UWMP and WSCP, including the basis for the preparation of the plan, individual or regional planning, fiscal or calendar year reporting, units of measure, and plan coordination and outreach.

2.1 BASIS FOR PREPARING A PLAN
The Act requires every “urban water supplier” to prepare and adopt a UWMP, to periodically review its UWMP at least once every five years and make any amendments or changes which are indicated by the review. The Act also requires every “urban water supplier” to prepare and periodically update its WSCP.

While the WSCP is part of the UWMP, it may be adopted and amended separately from the UWMP. An “urban water supplier” is defined as a supplier, either publicly or privately owned, providing water for municipal purposes either directly or indirectly to more than 3,000 customers or supplying more than 3,000 acre-feet of water annually (AFY).

As shown in Table 2-1 (DWR Table 2-1 Retail), the City provided water to approximately 76,333 customer connections and supplied 49,738 acre-feet (AF) of potable water in 2025. The number of service connections represents available water service connections at the end of 2025 for each individual public water system (PWS), including water accounts with service connections that are not currently being billed.

The volume of water supplied in 2025 is based on the City's production data for each PWS.

Based on the City’s total number of service connections and quantity of urban water use, the City is required to prepare a UWMP and periodically update its WSCP. The City and MID’s last Joint UWMP, the Joint 2020 UWMP, was adopted by the Modesto City Council and MID Board of Directors in June 2021. The City’s WSCP was adopted concurrently in June 2021 with the Joint 2020 UWMP by separate resolution.
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Table 2-1. Public Water Systems (DWR Table 2-1 Retail)

2.2 REGIONAL PLANNING
As described in Section 2.3 below, the City and MID have prepared this Joint 2025 UWMP on an individual reporting basis, not part of a regional planning process. However, the City and MID coordinate routinely with each other, and with the cities and service areas that they serve, to ensure that a safe and reliable water supply is delivered to existing customers and that plans for serving future customers are implemented as efficiently as possible.

2.3 INDIVIDUAL OR REGIONAL PLANNING AND COMPLIANCE
This Joint 2025 UWMP has been prepared on an individual reporting basis, covering only the City and MID’s municipal water service area, as shown in Table 2-2 (DWR Table 2-2). The City does not participate in a regional alliance, and it has not prepared a Regional Urban Water Management Plan (RUWMP). As described below in Section 2.5, the City and MID have notified and coordinated planning and compliance with appropriate regional agencies and constituents.

CA5010010(a) City of Modesto 70,755 47,558
CA5010005 Salida 4,417 1,068
CA5010031(b) Ceres (Walnut Manor) 53 35
CA5010033 Grayson 278 127
CA5010029 Del Rio (Hillcrest) 407 759
CA5010034 North Turlock 52 25
CA5010023 South Turlock 335 166
CA5010035(c) Central Turlock 36 0
Total 76,333 49,738
Public Water System
Number Public Water System Name Number of Municipal Connections 2025 NOTES:
(a) The City of Modesto main PWS includes the contiguous unincorporated areas of the County such as Empire and parts of the City of Ceres (North Ceres).
(b) The Ceres Walnut Manor system is also known as "Payne" for the street where the well is located. (c) The Central Turlock water system is owned and managed by the City of Modesto, but is supplied water by the City of Turlock distribution system via an interconnection. Per the City of Turlock, approximately 5 MG of water was supplied to this system in 2025.

Volume of Water
Supplied 2025 (AF)
DWR NOTES:

Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3. This table identifies the unit of measure selected in Submittal Table 2-3. #20..
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Table 2-2. Plan Identification (DWR Table 2-2)

2.4 FISCAL OR CALENDAR YEAR AND UNITS OF MEASURE
The City is a water retailer, and MID is the City’s water wholesaler.

This Joint 2025 UWMP has been prepared on a calendar year basis, with the calendar year starting on January 1 and ending on December 31 of each year. Water use and planning data for the entire calendar year of 2025 has been included.

The water volumes in this Joint 2025 UWMP are reported in units of AF.

The City and MID’s reporting methods for this Joint 2025 UWMP are summarized in Table 2-3 (DWR Table 2-3).

Table 2-3. Supplier Identification (DWR Table 2-3)
Water Supplier is also a
member of a RUWMP
Water Supplier is also a
member of a Regional Alliance
Regional Urban Water Management
Plan (RUWMP)
Individual UWMP
Name of RUWMP or Regional Alliance
if applicable
(select from drop down list)
Select
Only
One
Type of Plan
Supplier is a wholesaler
Supplier is a retailer
UWMP Tables are in calendar years
UWMP Tables are in fiscal years
Unit AF
Type of Supplier (select one or both)
Fiscal or Calendar Year (select one)
If using fiscal years provide month and date that the
fiscal year begins (mm/dd)
Units of measure used in UWMP *
(select from drop down)
* Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Table 2-3.
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2.5 COORDINATION AND OUTREACH
This section includes a discussion of the City and MID’s inter-agency coordination and coordination with the general public. The UWMP Act requires the City and MID to coordinate the preparation of their UWMP and WSCP with other appropriate agencies and all departments within the City, including other water suppliers that share a common source, water management agencies, and relevant public agencies. These agencies, as well as the public, participated in the coordination and preparation of this Joint 2025 UWMP and are summarized in the sections that follow.

2.5.1 Wholesale and Retail Coordination
The City is one of the major domestic water purveyors in Stanislaus County, serving not only the City of Modesto but also the communities of Del Rio, Empire, Salida, Grayson, and parts of Ceres and Turlock.

MID is the City’s water wholesaler.

In accordance with CWC Section 10631, the City informed MID of projected water use in five-year increments for the period through 2050, as summarized in Table 2-3 (DWR Table 2-4 Retail) and Table 2-5 (DWR Table 2-4 Wholesale). MID provided information to the City, identifying and quantifying water supplies available for the same period, under normal water year, single dry year, and five dry years hydrological conditions.

Table 2-4. Water Supplier Information Exchange (DWR Table 2-4 Retail) Table 2-5. Water Supplier Information Exchange (DWR Table 2-4 Wholesale) The retail Supplier has informed the following wholesale supplier(s) of projected water use in accordance with Water Code Section 10631.

Wholesale Water Supplier Name
Modesto Irrigation District (MID)
Supplier has informed more than 10 other water suppliers of water supplies available in accordance with Water Code Section 10631.

Completion of the table below is optional. If not completed, include a list of the water suppliers that were informed.

Provide page number for location of the list.

Supplier has informed 10 or fewer other water suppliers of water supplies available in accordance with Water Code Section 10631.

Complete the table below.

Water Supplier Name
City of Modesto
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2.5.2 Coordination with Other Agencies and the Community The City and MID actively encourage community participation in water management activities and specific water-related projects. The City’s public participation program includes both active and passive means of obtaining input from the community, such as mailings, public meetings, and web-based communication.

The City’s website describes on-going projects and posts announcements of planned rate increases to fund these water projects.

MID provides educational videos on water to classrooms within the District free of charge. MID’s website solicits public comment on water projects, as well as providing public information.

As part of the Joint 2025 UWMP and the City’s WSCP update, the City and MID facilitated a public review period. Public noticing, pursuant to Section 6066 of the Government Code, was conducted prior to commencement of this public comment period. Public hearing notices are included in Appendix D of this plan. During the public comment period, the Draft Joint 2025 UWMP was made available at the City’s Utilities Department and at the MID Board Secretary’s Office, as well as on the City and MID websites.

The public hearings provided an opportunity for all water users and the general public to become familiar with the Joint 2025 UWMP and ask questions about the City and MID’s water supply, in addition to their continuing plans for providing a reliable, safe, high quality water supply.

2.5.3 Notice to Cities and Counties
CWC § 10621 (b) requires agencies to notify the cities and counties to which they serve water at least 60 days in advance of the public hearing that the plan is being updated and reviewed. In January 2026, a notice of preparation was sent to the cities, counties, and communities served by the City and MID, as well as other nearby stakeholders, to inform them of the UWMP update process and schedule, and to solicit input for the Joint 2025 UWMP.

The City shared the notice of preparation of its UWMP and WSCP with several agencies, including relevant public agencies that utilize the same water supplies. These agencies included the following:
• Stanislaus County
• City of Turlock
• City of Ceres
• City of Oakdale
• City of Riverbank
• City of Waterford
• Grayson Community Service District
• South Modesto Municipal Advisory Council
• Turlock Irrigation District
• Oakdale Irrigation District
• Stanislaus County Farm Bureau
• Stanislaus and Tuolumne Rivers Groundwater Basin Association GSA • West Turlock Subbasin GSA
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• East Turlock Subbasin GSA
• Northwestern Delta-Mendota GSA
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CHAPTER 3
Service Area Description
This chapter provides a description of the City and MID’s water service area and includes a summary of water system facilities, climate, population associated with municipal water use, and land uses within the water service area.

3.1 GENERAL DESCRIPTION
The City of Modesto is located in the San Joaquin Valley, approximately 90 miles southeast of the San Francisco Bay Area and 77 miles south of the City of Sacramento. The City and MID’s water service areas are located in Stanislaus County. The City of Modesto is the largest incorporated city in Stanislaus County (County) and accounts for approximately 40 percent of the County’s population.

3.2 SERVICE AREA DESCRIPTION
The following sections briefly describe the geographical service area boundaries, water supplies, and water system facilities for the City and MID water systems.

3.2.1 Geographical Boundaries
Jurisdictional water service area boundaries for the City and MID are shown on Figure 3-1 and Figure 3-2, respectively.

3.2.1.1 City Service Area
The City’s service area consists of one large “contiguous” service area and several “outlying” non-contiguous service areas. The central contiguous service area is primarily defined by the City’s current sphere of influence (SOI) and includes the City of Modesto city limits, Salida, northern portions of Ceres, and several unincorporated Stanislaus County “islands.” These County islands include Empire, Bret Harte, and West Modesto, among several others. The outlying service areas are not contiguous to the central service area and include Grayson, Del Rio, Ceres (Walnut Manor), and portions of Turlock. The City also serves potable water to the Jennings Wastewater Treatment Plant (WWTP) via a groundwater well located at the plant.

3.2.1.2 MID Service Area
MID is primarily an agricultural water supplier. While MID delivers treated water on a wholesale basis to the City, and the City then delivers the water to its municipal and industrial customers, MID does not directly serve any retail (municipal) water customers. The place of use for MID’s treated wholesale water is defined by the area where the MID water service area boundary overlaps with the City’s water service area north of the Tuolumne River. The common City and MID water service area excludes portions of the City of Modesto’s service area that lie outside the MID water service boundary. These excluded areas generally include the communities of Del Rio, Grayson, portions of Ceres and Turlock, and the part of the City’s service area that is located south of the Tuolumne River.

3.2.2 Water Supply Overview
The City has been providing potable water service to its urban area since 1895 through the purchase and acquisition of several private water companies. Until 1995, the sole source of water supply to the City was groundwater pumped from the San Joaquin Valley Groundwater Basin. In the early 1990s, the City, MID, and the former Del Este Water Company formed a partnership to use a portion of MID’s surface water #20..
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supplies for municipal water use. This shift to surface water supply has allowed the City to stabilize once declining groundwater levels and allow for groundwater aquifer recovery.

MID was formed as the second irrigation district in California in 1887. Since that time, MID has developed numerous water rights and associated facilities to provide agricultural irrigation water from the Tuolumne River. MID has also developed groundwater supplies for agricultural uses. For the current and projected planning timeframe in this Joint 2025 UWMP, it is assumed that MID would only provide wholesale treated surface water to the City for municipal use within the City’s contiguous service area located north of the Tuolumne River.

3.2.3 Water System Facilities
This section describes the water facilities that supply and deliver water to the City’s service area. As described above, MID is primarily an agricultural water supplier and operates extensive facilities to deliver agricultural water supplies. These facilities, although not described below, include a complex network of canals, pipelines, pumps, drainage features, and control structures.

3.2.3.1 Surface Water Supply
In the early 1990s, the City, MID, and the former Del Este Water Company (acquired by the City in 1995) formed the Modesto Domestic Water Partnership to use a portion of MID’s surface water rights for municipal uses. This partnership entered into a Treatment and Delivery Agreement (TDA) to cover the design, construction, operation (i.e., governing delivery of treated surface water from MID to the City), and financing for the Initial Phase (Phase One) of the Modesto Regional Water Treatment Plant (MRWTP).

This new surface water treatment plant, along with associated storage and delivery facilities, became operational in 1995, and the City has purchased wholesale treated surface water from MID since.

The MRWTP is owned and operated by MID and per the original TDA, Phase 1 of the MRWTP could deliver a total annual supply of up to 33,600 AFY to the City. This treated surface water supply from MID, coupled with the available groundwater supply (together termed a “conjunctive supply”), is used to meet the City’s water supply needs for municipal customers in the contiguous service area located north of the Tuolumne River (this is the southern boundary of the MID service area).

The MRWTP Phase Two Expansion project was completed in 2016 and provides the City with the ability to receive a total annual supply of up to 67,200 AFY. It should be noted that the total supply (67,200 AFY) is based on normal and wet year annual averages. The delivery of Phase One and Phase Two treated surface water is governed by the October 2005 Amended and Restated TDA (ARTDA), which includes formulas to determine supply reductions during dry years which are in parity with the allocations for MID’s agricultural customers.
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0 1 2
Scale in Miles
Notes:

1. Sphere of influence boundary obtained from the City on 11/6/2014.

2. The City's contiguous service area is co-terminus with the City's SOI boundary except for the Salida and North Ceres areas.

3. City limit boundary based on County GIS data downloaded on October 6, 2014.

Turlock
Grayson
Modesto
Salida
Empire
Del Rio
North Ceres
(Portion Served by Modesto)
Ceres (Walnut Manor)
Bret Harte
West Modesto
Stanislaus County
Merced County
CYRD
REEK

ST A NISLAUS RI VE R

SAN JOAQUIN RIVER

DRY CREEK

TUOLUMNE RIVE R

STANISLAUS RIVER
5 108
165
99 219
132
33 132

Legend
Sphere of Influence (SOI)
Contiguous Service Area
Contiguous Area Outside of SOI
Outlying Service Area
City Limits
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City of Modesto
Water Service Areas
City of Modesto/MID
Joint 2025 UWMP
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0 1.5 3
Scale in Miles
Notes:

1. Source: Modesto Irrigation District.

San Joaquin County
Tuolomne County

S AN JOAQUIN RIVER

DRYCRE EK

S TANISLAUS RIVER

TUOLUMNE RIVER

OAKDALE

RIVERBANK

MODESTO

WATERFORD

CERES HUGHSON

TURLOCK

PATTERSON
5 108
165
219
120
33 108
132
99 WOODWARD

RESERVOIR
RODDEN
LAKE

MODESTO

RESERVOIR

TURLOCK LAKE
MILLER
LAKE

Legend
MID Service Boundary
City
MID Pipeline/Lateral/Crossing
Railroad
Stanislaus County
Merced County
Figure 3-2
MID
Water Service Area
City of Modesto/MID
Joint 2025 UWMP
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3.2.3.2 Groundwater Supply
The City’s groundwater supply wells are located throughout the contiguous and outlying service areas, but all are within the San Joaquin Valley Groundwater Basin (Modesto, Turlock, and Delta-Mendota Subbasins). Residents within the contiguous service area north of the Tuolumne River (North Modesto, Salida, and Empire) generally rely on treated surface water supply from MID year-round and are supplemented with groundwater to meet increased water demands (primarily in the summer months).

Water demands from the contiguous service area located south of the Tuolumne River (South Modesto) and the outlying service areas are met exclusively with groundwater supply year-round. The City currently has 77 active groundwater wells to serve both the contiguous and outlying service areas. Of these active wells, 67 are located within the City’s contiguous service area, with the remaining 10 wells located within the outlying service areas. 1

3.2.3.3 Distribution System
The major water distribution system facilities in the City’s contiguous and outlying service areas are shown on Figure 3-3.

The City’s contiguous service area consists of approximately 900 miles of transmission and distribution pipelines. MID owns and operates a portion of the transmission mains traversing the City, and these transmission mains provide treated surface water through a series of turnouts that can control water supply into the City’s water distribution system. The contiguous service area is also served by the City’s groundwater wells and ten at-grade storage tanks, with a combined total storage capacity of 22 million gallons (MG).2 Each storage tank has a booster pump station to pump water from the tank into the distribution system. In addition, MID owns and operates two 5.0 MG Terminal Reservoirs (10.0 MG total) and an associated terminal pump station which deliver treated water from MID to the downstream transmission mains.

The City’s outlying service areas are served by groundwater wells located within each respective area.

Since completion of the Joint 2020 UWMP, the City has completed several improvements to the Grayson water system, including replacement of most distribution mains and meters, and construction of a new groundwater well (Well 69). In the Del Rio service area, the City recently constructed new Wells 68 and 70, as well as a new 0.25 MG tank and booster pump station. The City is actively working on equipping Del Rio’s Well 70 with wellhead treatment to improve water quality. The remaining outlying service areas are served by existing groundwater wells or through connections to neighboring agencies. 1 Number of active wells within contiguous and outlying service area is based on Excel spreadsheet ‘Well evaluation 1-21-2026’ provided by the City in January 2026. 2 Number and capacity of storage tanks is based on Excel spreadsheet ‘Well evaluation 1-21-2026’ provided by the City in January 2026.
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3.3 SERVICE AREA CLIMATE
The climate of the City and MID’s service areas is best described as Mediterranean, characterized by hot, dry summers and cool winters. This section describes the historical climate and potential effects of climate change.

The climate ranges from summer temperatures exceeding 90 degrees Fahrenheit (°F), and winter temperatures dropping into the mid-30°F range. Precipitation in the area averages about 12.2 inches per year.

3.3.1 Historical Climate
Water use within the City’s service area is dependent on various climate factors such as temperature, precipitation, and evapotranspiration (ET). Climate data, including temperature and precipitation estimates, were obtained for the City from the Western Regional Climate Center and the California Irrigation Management Information System (CIMIS).

ET describes the combined water lost through evaporation from the soil and surface water bodies and plant transpiration. In general, the ET is given for turf grass and then corrected for a specific crop type.

Local ET data was obtained from the CIMIS monitoring station in West Modesto (Station #71). The historical climate characteristics affecting water management in the City and MID’s service areas are shown in Table 3-1.

Table 3-1. Monthly Average Climate Data Summary(a)
Month
Standard Monthly
Average ET, inches(a)
Average Total
Rainfall, inches(b)
Average Temperature, degrees Fahrenheit(a)
Minimum Maximum
January 1.17 2.44 36.4 55.8
February 1.98 2.07 37.9 61.3
March 3.61 1.93 40.2 66.4
April 5.26 1.03 43.3 71.7
May 6.98 0.46 47.9 78.9
June 7.96 0.13 52.3 85.8
July 8.03 0.02 55.9 90.7
August 6.96 0.04 55.2 89.2
September 5.20 0.17 52.3 85.7
October 3.54 0.63 46.1 76.9
November 1.79 1.24 38.9 64.7
December 1.09 2.05 35.4 55.5
Total 53.6 12.2 - -
(a) California Irrigation Management Information System (https://cimis.water.ca.gov/) for Station #71. Period of record is years 1990 through 2025. Data accessed 12/18/2025.
(b) Western Regional Climate Center (https://wrcc.dri.edu/) data for Modesto City Station (045738). Period of record is years 1906 through 2016. Data accessed 12/18/2025.
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These climate characteristics highly influence the City’s water use. As described in Chapter 4, the City’s water use in the summer months is significantly higher than that in the winter, reflecting increased water use for irrigation purposes during the hot, dry summers.

3.3.2 Potential Effects of Climate Change
The CWC requires urban water suppliers to account for the impacts of climate change on water supplies and supply reliability. A discussion of the effects of climate change on water demands, supplies, and reliability can be found in Chapter 4 (Water Use Characterization), Chapter 6 (Normal-Year Water Supply Characterization), and Chapter 7 (Water Service Reliability) of this plan. This section summarizes those discussions.

In general, climate change is expected to increase water demand for irrigation and the year-to-year variability of water demands. This is the result of increased temperatures (which increases ET) and more variability in precipitation (which impacts supply availability and reliability). Also, natural disasters such as wildfires, droughts, and floods are expected to increase in both frequency and intensity.

Responding to climate change generally takes two forms: mitigation and adaptation. Mitigation is taking steps to reduce the contribution to the causes of climate change by reducing greenhouse gas (GHG) emissions. Adaptation is the process of responding to the effects of climate change by modifying systems and behaviors to function in a warmer climate.

In the water sector, climate change mitigation is generally achieved by reducing energy use, increasing energy efficiency, and/or substituting fossil fuel‐based energy sources for renewable energy sources where feasible. Because water requires energy to move, treat, use, and discharge, water conservation also results in energy conservation. Adaptation initiatives could include diversification of the City and MID’s water supply portfolio, increased conjunctive use, and introduction or expansion of recycled water use. However, as discussed in Chapter 6, secondary treated effluent is used to irrigate City-owned ranch lands, and the City delivers tertiary treated recycled water to Del Puerto Water District for agricultural irrigation, which improves regional water supply resiliency. Therefore, the City does not have plans to use recycled water beyond what is currently delivered for agricultural irrigation.

3.4 SERVICE AREA POPULATION AND DEMOGRAPHICS

3.4.1 City of Modesto Water Service Area Population
The City has historically been among the fastest growing areas in California. The City’s population grew steadily from 1996 through 2004 (at an average rate of 1.8 percent per year). However, since 2005, growth within the City’s service area has slowed significantly as a result of national and statewide economic factors. The City’s population has grown approximately 8.8 percent from 2010 through 2025, which translated to an average rate of 0.59 percent per year, which is much less than the growth it experienced prior to 2004.

Historical population estimates for the City’s water service area are based on Census data from California Department of Finance (DOF) Report E-4, with the 2020 Census Benchmark, where available. Where DOF data is not available (e.g., Turlock, Ceres (Walnut Manor), and other County pockets), population has been estimated based on a count of existing dwelling units served by the City (from aerial photographs and billing data), and an estimated housing density (people per dwelling unit) based on Census data for the surrounding communities.
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Consistent with the City's other recent infrastructure planning studies, it is assumed that future growth within City limits will be at an annual rate of approximately 0.8 percent. This growth rate is based on recent City growth between 2010 through 2020 and does not account for the lower growth rate seen over the past five years (2020 through 2025).

The projected 2050 population for the City’s contiguous and outlying water service areas is estimated at approximately 328,490 people and represents a 21 percent increase from the current (2025) population.

Growth within the City’s water service area has been slower than previously projected. The City’s 2017 Water Master Plan (WMP) had projected a water service area population of 393,594 people by 2050, representing an 18 percent difference compared to the updated projection of 328,490 people.

The growth assumptions used to project the population for each portion of the City’s water service area are summarized below:
• City of Modesto: Moderate growth assuming a 0.8 percent average annual growth rate • Salida: Moderate growth assuming a 0.8 percent average annual growth rate • Community of West Modesto: Moderate growth up to buildout of approximately 9,000 people by 2050
• Del Rio: Moderate growth up to buildout of approximately 2,000 people by 2050 • Rouse: Minor growth up to buildout of approximately 2,875 people by 2050 • Grayson: Minor growth up to buildout of approximately 880 people by 2030 • Communities of Empire, North Ceres (Bystrom), Bret Harte, Parklawn, and most other County pockets: Fully developed; no (or very little) additional growth anticipated • Turlock: Fully developed; no additional growth anticipated • Ceres (Walnut Manor): Fully developed; no additional growth anticipated. Assumed to be served by City of Turlock water system in future
Table 3-2 (DWR Table 3-1 Retail) summarizes the current and projected population for the City’s contiguous and outlying water service areas. Actual population growth and timing may vary depending on development timing and other factors.

Table 3-2. Population – Current and Projected (DWR Table 3-1 Retail) 2025 2030 2035 2040 2045 2050(opt)
270,450 282,120 293,410 305,100 317,200 328,490
Population
Served
NOTES: The current and projected population includes the City of Modesto incorporated area and other outlying water service areas outside of Modesto city limits.
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3.4.2 MID Population
As stated previously, MID does not directly serve any municipal water customers, and does not plan to do so in the future, as summarized in Table 3-3 (DWR Table 3-1 Wholesale). MID does use some potable water for on-site use at the MRWTP for its 24 MRWTP staff; however, the quantity of water is negligible and therefore this population is excluded from Table 3-3 (DWR Table 3-1 Wholesale).

Table 3-3. Population – Current and Projected (DWR Table 3-1 Wholesale)

3.4.3 Other Social, Economic, and Demographic Factors
The State requires the inclusion of service area socioeconomic information as part of the system description in UWMPs. However, differences in household water use across sociodemographic groups in the City have not been studied. Therefore, the following social, economic, and demographic information is being provided to comply with the regulation. The information was derived from the US Census Bureau’s profile of the City of Modesto for 2019-2023.
3 • The average number of people per household was 2.98. • The median household income was $77,899.
• The unemployment rate was 7.3 percent.
• The owner-occupied housing unit rate was 58.4 percent, with a median home value of $415,600. • The median gross rent was $1,609 per month.
• The median age was 35.4 years.
• Of persons 25 years or older, 83.3 percent had earned at least a high school diploma or equivalent, and 20.3 percent had earned a bachelor’s degree or higher. • Of persons between 17 years to 64 years old, 11.7 percent had a disability, and 5.4 percent did not have health insurance.
• Approximately 96.0 percent of households had a computer, and 91.8 percent had a broadband internet subscription.
• By race/ethnicity, 50.8 percent of people were White, 4.7 percent were Black, 1.3 percent were American Indian or Alaska Native, 7.4 percent were Asian, 0.9 percent were Hawaiian Native or Pacific Islander, 22.6 percent were two or more races, and 12.3 percent were some other race.
3 United States Census Bureau. American Community Survey, 2023: ACS 5-Year Estimates Data Profiles for City of Modesto, California. Accessed at
https://data.census.gov/table/ACSDP5Y2023.DP03?q=Modesto+city,+California&y=2023&d=ACS+5- Year+Estimates+Data+Profiles on December 17, 2025. 2020 2025 2030 2035 2040 2045(opt) 0 0 0 0 0 0
Population
Served
NOTES: MID does not directly serve any urban water customers. The population served by MID wholesale water is included in the City's total service area population (see DWR Table 3-1 Retail).
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• Approximately 43.9 percent of people were Hispanic or Latino (i.e., of Hispanic origin), while

56.1 percent were not of Hispanic origin.
• Approximately 18.7 percent of residents were foreign born, and 37.8 percent of people of age five years and older spoke a language other than English at home.

3.5 LAND USES WITHIN SERVICE AREA
Existing and future land uses within the City’s water service area are currently specified in its Urban Area General Plan, which was adopted in 2019. A previous iteration of the General Plan land use diagram was used in the City’s 2017 WMP to develop future water demand projections. The land use diagram in the current Urban Area General Plan is similar to the land use diagram used in the 2017 WMP.

The City is currently preparing an update to the Urban Area General Plan, known as the General Plan 2050 Comprehensive Update.
4 This update process will plan the City’s long-term growth through the year 2050.

Future UWMP updates will incorporate the General Plan 2050 Comprehensive Update, which may lead to updated water demand projections due to changes in land use projections.

3.5.1 Existing Land Uses within Service Area
Most of the City’s existing water service area consists of residential land use, including most customers in Del Rio, Grayson, Ceres (Walnut Manor), and portions of Turlock. Industrial land use is concentrated in the southeast region of the contiguous service area, while commercial and mixed use land uses are spread throughout the contiguous service area.

3.5.2 Future Land Uses within Service Area
The 2017 WMP identified approximately 11,000 acres of vacant parcels within the City’s contiguous service area, with over 90 percent of this vacant area located in North Modesto and the remainder in South Modesto. These parcels are designated in the General Plan with future land uses of mostly Business Park, Village Residential, Residential, or Industrial. It is expected that many of these vacant parcels will develop in the future, leading to an increase in service area population as described in Section 3.4.1, and increased water demands as described in Chapter 4.

Since development of the City/MID Joint 2020 UWMP, the City has made the following General Plan Land Use Element amendments:
• 23 acres from Commercial to Village Residential, SE corner of Hatch and Carpenter Road (Resolution 2022-100)
• 67 acres from Business Park to Mixed Use, north side of Pelandale between Dale Road and American Avenue (Resolution 2022-193)
• 25 acres Regional Commercial to Residential, in the Tivoli Specific Plan (Resolution 2022-449)
• 140 acres from Business Park-Commercial-Residential to Residential, east side of Claus Road, at Merle Avenue and north of East Briggsmore (Resolution 2024-022) 4 City of Modesto. Modesto 2050. Accessed at https://gp2050.modestogov.com/ on March 24, 2026. #20..
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• 12.6 acres from Regional Commercial to Residential (Tivoli Specific Plan) (Resolution 2025-164)
• 70 acres Business Park to Residential, north side of Pelandale between Tully Road and Tidewater RR/Virginal Trail (Resolution 2025-247)
The City’s upcoming General Plan 2050 Comprehensive Update will provide additional land use zoning updates, which will be incorporated into future UWMP updates.

The Salida service area also expects growth from implementation of the Salida Community Plan (SCP), a land use framework that guides development in the unincorporated Salida area. The SCP includes planning and guidance for the development of approximately 4,600 acres of land which includes the existing community of Salida (referred to as the Existing Plan Area), as well as planned future development (referred to as the Amendment Area).

In 2007, the Stanislaus County Board of Supervisors approved the Salida Area Planning, Road Improvement, Economic Development, and Farmland Protection Initiative, which established a planning framework for development north of the existing community. Stanislaus County is now preparing environmental documentation, including a program‑level environmental impact report (PEIR), to evaluate future development within the SCP Amendment Area. The Amendment Area encompasses approximately 3,383 acres identified for long‑term future growth. Planned development within the Amendment Area includes a mix of residential, industrial, business park, and commercial uses, including approximately 5,000 new dwelling units, 1,259 acres of industrial use, 490 acres of business park use, and 280 acres of commercial use.5 Much of the Amendment Area lies within the City’s General Plan planning area and is anticipated to rely on the City of Modesto for municipal water service when development occurs.

For the outlying service areas, some residential development is expected in Del Rio, along with minimal residential development in Grayson. Ceres (Walnut Manor) and the portions of Turlock served by the City of Modesto are fully developed.
5 Stanislaus County. September 2024. NOTICE OF PREPARATION OF A PROGRAM ENVIRONMENTAL IMPACT REPORT NO. PLN2024-0083 - SALIDA COMMUNITY PLAN AMENDMENT AREA. Accessed at https://www.stancounty.com/planning/pl/act-proj/PLN2024-0083_NOP.pdf on March 25, 2026. #20..
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CHAPTER 4
Water Use Characterization
This chapter describes and quantifies the City and MID’s historical, current, and projected water use. It discusses both the City’s retail water demands and MID’s wholesale water demands. Since MID supplies treated surface water to the City, and since the City is its only retail customer, MID’s demand projections are consistent with and based on the projected growth within the City’s water service area and the City’s estimated surface water and local groundwater use. Accurately tracking and reporting water demands allows the City and MID to properly analyze the use of their resources and conduct effective water resource planning.

4.1 NON-POTABLE VERSUS POTABLE WATER USE
The City treats local groundwater to potable water standards and purchases potable surface water from MID. Potable water is defined as water that is safe to drink and typically has had various levels of treatment and disinfection.

Non-potable water is not safe to drink, which generally includes both raw water and recycled water. Raw water is untreated water that is used in its natural state and/or with minimal treatment. The City uses raw water from shallow, on-site wells at several local parks for landscape irrigation. These wells are not part of the City’s potable water system. Recycled water is municipal wastewater that has been treated to a specified quality that allows for re-use.

The City currently uses secondary treated wastewater effluent and treated cannery wastewater effluent for agricultural irrigation of roughly 2,500 acres of fodder and feed crops on City-owned land. The City also produces disinfected tertiary treated recycled water, which is exported outside of the City’s water service area for agricultural irrigation as part of the North Valley Regional Recycled Water Program (North Valley Program). Due to geographical and financial constraints to supply recycled water inside the City’s water service area, the City implemented the North Valley Program to supply recycled water to the neighboring Del Puerto Water District for agricultural irrigation. Therefore, the City does not currently use recycled water in its water service area, nor does it anticipate doing so in the future. Additional information on the North Valley Program is provided in Chapter 6.

MID does not currently deliver recycled water to its wholesale customers, nor does it have plans to do so.

Potable water demands and raw water demands are discussed in the following sections.

4.2 WATER USE BY SECTOR
This section describes the City and MID’s past, current, and projected water use by water use sector, as listed in CWC §10631(d) and defined in the DWR Guidebook. The following classifications were used to analyze current consumption patterns among the City’s water use sectors. Each of the City’s retail water use sectors are listed and defined below:
• Single-family residential: A single-family dwelling unit. A lot with a free-standing building containing one dwelling unit that may include a detached secondary dwelling. • Multi-family residential: Multiple dwelling units contained within one building or several buildings within one complex.
• Commercial: A water user that provides or distributes a product or service (CWC § 10608.12(d)).
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• Industrial: A water user that is primarily a manufacturer or processor of materials as defined by the North American Industry Classification System (NAICS) code sectors 31 to 33, inclusive, or an entity that is a water user primarily engaged in research and development (CWC § 10608.12(h)).
• Institutional (and Governmental): A water user dedicated to public service. This type of user includes, among other users, higher education institutions, schools, courts, churches, hospitals, government facilities, and nonprofit research institutions (CWC § 10608.12(i)). • Landscape: Water connections supplying water solely for landscape irrigation. Such landscapes may be associated with multi-family, commercial, industrial, or institutional/governmental sites but are considered a separate water use sector if the connection is solely for landscape irrigation.
• Distribution System Losses: The difference between the actual volume of water treated and delivered into the distribution system and the actual metered consumption.

The City does not have any current plans to use its potable water or raw water for agricultural irrigation, wetlands, wildlife habitat, or saline water intrusion barriers. As described in Chapter 6, the City does use recycled water for agricultural irrigation and is also evaluating potential groundwater recharge projects to augment groundwater supplies in the future.

As discussed in Chapter 3, MID is primarily an agricultural water supplier. Because MID does not directly serve retail customers, the only DWR defined sector relevant to MID in this Joint UWMP is “sales to other agencies”, which are water sales made to the City of Modesto. For information on MID’s agricultural water use, refer to MID’s 2025 Agricultural Water Management Plan (AWMP).

MID’s projected sales to the City of Modesto are based on projected water demands provided by the City.

There is inherent uncertainty in future demand projections and, therefore, any projected sales reported in the Joint UWMP are for planning purposes only and are not considered a commitment on the part of the wholesaler or retailer.

4.2.1 Historical Potable Water Use
The City and MID’s past potable water use in recent years is discussed in the following sections.

4.2.1.1 City of Modesto
The City’s potable water demand by water use type from 2020 through 2024 is shown in Table 4-1. Water use data is from the City’s metered consumption records and includes water use within both the City’s contiguous service area and outlying service areas, as shown in Chapter 3. Totals shown are based on the City’s total annual water production (i.e., the sum of groundwater pumping and surface water deliveries).

Losses are calculated as the difference between total potable water production and total metered potable water consumption. The 2020 volumes are consistent with those presented in the City/MID Joint 2020 UWMP.

As shown in Table 4-1, single family residential customers and commercial customers have been the two largest water use types for the City in past years. Losses represented approximately 10 percent of total production in 2020. Since then, losses have been less than or equal to 3 percent of total production. #20..
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Table 4-1. City’s Historical Potable Water Use by Sector(a), AF Use Type 2020 2021 2022 2023 2024
Single Family 27,081 26,906 26,559 23,728 24,645
Multi-Family 5,420 6,596 6,490 5,857 6,138
Commercial 8,110 9,445 9,319 9,157 9,565
Industrial 2,115 2,283 2,466 2,230 2,540
Institutional/Governmental 1,933 2,564 2,751 2,273 2,362 Landscape 2,520 2,943 2,992 2,720 2,986
Other - Unmetered Water Uses 615 0 0 0 0
Losses(b) 5,310 1,795 1,172 1,224 1,593
Total 53,104 52,533 51,748 47,189 49,829
(a) Values are based on metered consumption and metered production within the City’s contiguous service area and outlying service areas. Data for 2020 is based on the City/MID Joint 2020 UWMP. Data for 2021 through 2024 was provided by the City in January 2026. (b) Losses are calculated as the difference between total production and total metered consumption.

4.2.1.2 MID
MID’s wholesale potable water sales to the City of Modesto from 2020 through 2024 are shown in Table 4-2. MID has not delivered potable, raw, or recycled water directly to urban retail customers in the past and does not plan to do so in the future.

Table 4-2. MID’s Historical Wholesale Potable Water Use(a), AF Use Type 2020 2021 2022 2023 2024
Sales to Other Agencies 26,053 28,945 23,698 24,600 25,255 (a) Values are based on metered deliveries of treated surface water to the City of Modesto. Data for 2020 is based on City/MID Joint 2020 UWMP. Data for 2021 through 2024 was provided by the City in January 2026.

4.2.2 Current Water Use
The City and MID’s current water use in 2025 is discussed in the following sections.

4.2.2.1 City of Modesto
The City’s water demand by water use type in 2025 is reported in Table 4-3 (DWR Table 4-1 Retail). The City’s total potable water use in 2025 was 49,738 AF, including system losses. Losses are calculated as the difference between total potable water production (49,738 AF) and total metered potable water consumption, or approximately 5.4 percent of total potable water production. The City’s total non-potable water use in 2025 was estimated to be 1,865 AF, all of which was untreated groundwater used for landscape irrigation at City parks.
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Table 4-3. Uses for Potable and Non-Potable Water in 2025 – Actual (DWR Table 4-1 Retail)

4.2.2.2 MID
MID’s water sales to the City of Modesto in 2025 are reported in Table 4-4 (DWR Table 4-1 Wholesale).

MID delivered a total volume of 29,125 AF of treated surface water to the City of Modesto in 2025.1 As shown, all water deliveries were treated to potable water standards. 1 The City reported 29,125 AF in its 2021–2025 Production spreadsheet. MID’s reported plant production total for calendar year 2025 is 29,171 AF, which is 46 AF higher (a 0.16 percent difference). Although minor, this discrepancy should be noted. For consistency, the value of 29,125 AF was used throughout this plan.

Use Type
Drop down list
May select each use multiple times
These are the only use types that will be
recognized by the WUEdata online
submittal tool
Potable or NonPotable
(OPTIONAL)
Drop down list
Volume (AF)
Single Family Potable 24,361
Multi-Family Potable 5,837
Commercial Potable 9,041
Industrial Potable 2,855
Institutional/Governmental Includes schools and churches. Potable 2,328 Landscape Potable 2,651
Losses See note (b). Potable 2,666
Landscape Raw water irrigation wells. See
note (c). Non-Potable 1,865
49,738
1,865
Total 51,603
NOTES:
(a) Water use is based on metered water consumption and includes water use by all public water systems listed in Table 2-1 (DWR Table 2-1 Retail).
(b) Losses are calculated as the difference between total production (including groundwater and purchased surface water) and metered consumption.
(c) Raw water irrigation wells are not metered. Annual use is estimated based on the irrigable area of individual parks served.

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Table 4-4. Uses for Potable and Non-Potable Water – Actual (DWR Table 4-1 Wholesale)

4.2.3 Projected Water Use
The City and MID’s projected water use through 2050 is discussed in the following sections.

4.2.3.1 City of Modesto
The City’s projected potable and non-potable water demands for 2030 through 2050 (representing a 25-year planning horizon from 2025) are presented in Table 4-5 (DWR Table 4-2 Retail). By 2050, the City’s total projected potable water demand is estimated to be 64,390 AF, which represents a 29 percent increase compared to the 2025 potable demand of 49,738 AF.

Future potable water demands were projected based on the forecasted population within the City’s water service area, as described in Chapter 3. Demands were projected by applying a per capita water use factor of 175 gallons per capita per day (GPCD) to the forecasted service area population. This factor was selected based on a review of the City’s per capita water use over the past five years (2021 through 2025), which ranged between 157 GPCD and 176 GPCD. The per capita water use factor reflects total systemwide demand, including residential, commercial, industrial, institutional, and landscape demands, as well as water losses. The projected demands by use type were estimated using the average proportion of total water demand attributed to each use category over the past five years (2021 through 2025).

Recent per capita water use has been significantly lower due to water conservation efforts. For comparison, the City’s average per capita water use from 2010 through 2014 was 218 GPCD. 2 This has
resulted in lower water demand projections compared to previous planning efforts, including the City’s 2017 WMP and City/MID Joint 2020 UWMP.

The 2017 WMP had assumed buildout of the City’s contiguous service area around 2050, with a total demand of approximately 100,000 AFY by 2050. The 2017 WMP projected buildout demands using a unit water demand method based on the City’s Proposed General Plan land use designations, which was then verified using a per capita water use (population-based) method. The unit water demand factors were 2 City of Modesto. September 2017. Water Master Plan. Use Type Drop down list
May select each use multiple times
These are the only use types that will be
recognized by the WUEdata online
submittal tool
Potable or Non-Potable
(OPTIONAL)
Drop down list
Volume (AF)
Sales to other agencies Sale of treated surface water
to City of Modesto Potable 29,125
29,125
0 29,125
NOTES: Volume is based on metered MID water production provided by the City in January 2026.

DWR NOTES: Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3. This table identifies the unit of measure selected in Submittal Table 2-3.

Total
2025 Actual Water Use
Subtotal Potable
Subtotal Non-Potable
Additional Description
(as needed)
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developed based on metered water consumption in 2009 through 2013, and the population-based method used a per capita water use of 228 GPCD from the City’s SB X7-7 2020 water use target. The Joint 2020 UWMP demand projections used the City’s 2017 WMP demand projections but applied a 15 percent reduction to account for actual demands being lower at the time than the 2017 WMP projections.

Demand projections in this Joint 2025 UWMP are lower than the projections in the City’s 2017 WMP and the City/MID Joint 2020 UWMP for several reasons:
• Growth within the City’s service area has been slower than assumed in the 2017 WMP, as described in Chapter 3.
• Conservation efforts have substantially lowered actual water use, resulting in reduced unit water demand factors compared to the 2009 to 2013 usage data used in the 2017 WMP’s land use-based projection method.
• The per‑capita factor used in this Joint 2025 UWMP (175 GPCD) is significantly lower than the 228 GPCD SB X7‑7 2020 target, or a 23 percent reduction, used in the 2017 WMP’s population‑based projection method.

Projected non-potable water demands within the City’s service area, which include landscape irrigation using raw water wells, are expected to remain generally constant through 2050. Refer to Chapter 6 for a discussion of the City’s recycled water demands outside of its water service area.

Table 4-5. Uses for Potable and Non-Potable Water – Projected (DWR Table 4-2 Retail) Use Type
Drop down list
May select each use multiple
times
These are the only Use Types
that will be recognized by the
WUEdata online submittal tool
Potable or NonPotable
(OPTIONAL)
Drop down list
2030 (AF) 2035 (AF) 2040 (AF) 2045 (AF) 2050 opt (AF)
Single Family Potable 27,800 28,916 30,067 31,259 32,369 Multi-Family Potable 6,811 7,084 7,366 7,658 7,930
Commercial Potable 10,249 10,661 11,085 11,525 11,934
Industrial Potable 2,726 2,835 2,948 3,065 3,174
Institutional/Governmental Includes schools and
churches. Potable 2,704 2,813 2,925 3,041 3,149
Landscape Potable 3,148 3,275 3,405 3,540 3,666
Losses Potable 1,861 1,936 2,013 2,093 2,167
Landscape Raw water irrigation
wells Non-Potable 1,865 1,865 1,865 1,865 1,865
55,300 57,520 59,810 62,180 64,390
1,865 1,865 1,865 1,865 1,865
57,165 59,385 61,675 64,045 66,255
Projected Water Use
(Report To the Extent that Records are Available)
Additional
Description
(as needed)
NOTES: Potable demand projections are based on the forecasted population growth within the water service area and an estimated per‑capita water use of 175 gallons per capita per day (gpcd). Demand by use type is estimated using the average proportion of total water demand attributed to each use category over the past five years (2021–2025). Non-potable demands associated with landscape irrigation are expected to stay constant.

Total
DWR NOTES: Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3. This table identifies the unit of measure selected in Submittal Table 2-3.

Subtotal Non-Potable
Subtotal Potable
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4.2.3.2 MID
MID’s projected water sales to the City of Modesto are provided in Table 4-6 (DWR Table 4-2 Wholesale).

As noted previously, MID has not delivered potable, raw, or recycled water directly to urban retail customers in the past and does not plan to do so in the future.

MID’s water sales to the City of Modesto are anticipated to increase through 2050 to approximately 45,073 AF, which remains below the City’s available Phase 2 MRWTP annual supply of 67,200 AF. MID’s sales to the City are projected based on the City’s retail water use projections shown in Table 4-5 (DWR Table 4-2 Retail), and assuming that the City plans to use surface water to meet 70 percent of its total demandsin normal and wet years with no reductions in surface water, with the remaining 30 percent met by groundwater. During dry years, the City may need to increase groundwater use to make up for reduced surface water allocations.

Over the past five years (2021 through 2025), surface water use has represented between 46 percent to 59 percent of total annual production, at an average of 52 percent of total annual production. The projections shown in Table 4-6 assume that the City may use surface water to meet up to 70 percent of its total demands to further reduce reliance on groundwater. However, the actual proportion of surface water and groundwater use may differ due to various operational factors.

Projected water sales to the City are presented for planning purposes. Actual water sales may vary and are dependent on system demands and hydrologic conditions during each respective year.

Table 4-6. Uses for Potable and Raw Water – Projected (DWR Table 4-2 Wholesale) Use Type
Drop down list
May select each use multiple
times
These are the only Use Types
that will be recognized by
the WUEdata online
submittal tool.

Potable or NonPotable
(OPTIONAL)
Drop down list
2030 (AF) 2035 (AF) 2040 (AF) 2045 (AF) 2050 opt (AF)
Sales to other agencies Sale of treated surface
water to City of Modesto Potable 38,710 40,264 41,867 43,526 45,073 38,710 40,264 41,867 43,526 45,073
0 0 0 0 0
38,710 40,264 41,867 43,526 45,073
NOTES: Projected surface water sales to the City of Modesto based on the City's projected water demands shown in Table 4-5 (DWR Table 4-2 Retail), and assuming that the City plans to use surface water to meet 70 percent of its total demands, with the remaining 30 percent met by groundwater. All treated surface water deliveries will be made in accordance with the ARTDA.

DWR NOTES: Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3. This table identifies the unit of measure selected in Submittal Table 2-3.

Total
Projected Water Use (Report To the Extent that Records are Available) Subtotal Potable
Subtotal Non-Potable
Additional Description
(as needed)
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4.2.4 Characteristic Five-Year Water Use
Water Code Section 10635(b) requires urban suppliers to include a five-year DRA in their UWMPs. A key component of the DRA is estimating water demands for the next five years (2026-2030) without drought conditions (i.e., unconstrained demand). Chapter 7 details the DRA, but the five-year demand projections for the City and MID are summarized in the following sections.

4.2.4.1 City of Modesto
Table 4-7 shows the City’s five-year potable demand projections (2026-2030) for its DRA. The City’s projected water demands for 2026 through 2029 were estimated as a linear interpolation between the actual 2025 consumption by use type, reported in Table 4-3 (DWR Table 4-1 Retail), and the 2030 projected water use, reported in Table 4-5 (DWR Table 4-2 Retail).

Table 4-7. City’s Projected Five-Year Potable Water Demands for Drought Risk Assessment(a) Use Type
Water Demands, AF
2026 2027 2028 2029 2030
Single Family 25,049 25,736 26,424 27,112 27,800
Multi-Family 6,032 6,226 6,421 6,616 6,811
Commercial 9,283 9,524 9,766 10,008 10,249
Industrial 2,829 2,803 2,777 2,752 2,726
Institutional/Governmental 2,403 2,478 2,554 2,629 2,704 Landscape 2,751 2,850 2,950 3,049 3,148
Losses 2,505 2,344 2,183 2,022 1,861
Total 50,850 51,963 53,075 54,188 55,300
(a) Potable demand projections for 2026-2029 are based on linear interpolation of the City’s actual 2025 potable demands presented in Table 4-3 (DWR Table 4-1 Retail) and 2030 potable demand projections presented in Table 4-5 (DWR Table 4-2 Retail).

4.2.4.2 MID
Table 4-8 shows MID’s five-year wholesale demand projections (2026-2030) for its DRA. MID’s projected wholesale demands for 2026 through 2029 were estimated as a linear interpolation between the actual 2025 water sales to the City, reported in Table 4-4 (DWR Table 4-1 Wholesale), and the 2030 projected water sales, reported in Table 4-6 (DWR Table 4-2 Wholesale). The 2030 projected water sales assumes that the City uses surface water to meet 70 percent of its projected 2030 water demand. Actual water sales may vary and are dependent on system demands and hydrologic conditions during each respective year.

Table 4-8. MID’s Projected Five-Year Wholesale Water Demands for Drought Risk Assessment(a,b) Use Type
Water Demands, AF
2026 2027 2028 2029 2030
Sales to Other Agencies 31,042 32,959 34,876 36,793 38,710 (a) Wholesale demand projections for 2026-2029 are based on linear interpolation of MID’s actual 2025 demands presented in Table 4-4 (DWR Table 4-1 Wholesale) and 2030 demand projections presented in Table 4-6 (DWR Table 4-2 Wholesale). (b) Values are presented for planning purposes. Actual water sales may vary and are dependent on system demands and hydrologic conditions during each respective year.
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4.2.5 Estimating Future Water Savings
As described in Section 4.2.3, the City’s water use projections are based on the forecasted population growth within the City’s water service area and an assumed per capita water use of 175 GPCD. This per capita water use factor is based on the City’s recent water use trends over the past five years and represents a significant reduction compared to the previous decade. As a result, the City’s water conservation efforts are already incorporated into the water demand projections shown in Table 4-5 (DWR Table 4-2 Retail).

When projecting future water demands, urban water suppliers may also account for passive water savings resulting from codes, standards, ordinances, or transportation and land use plans. These passive savings can reduce projected water use for new and future customers compared to historical usage patterns. However, as indicated in Table 4-9 (DWR Table 4-3 Retail), these potential passive savings have not been included in the City’s water demand projections. This conservative approach ensures that future water supply needs are not underestimated.

Table 4-9. Inclusion in Water Use Projections (DWR Table 4-3 Retail)

4.2.6 Water Use for Lower Income Households
SB 1087 (2006) requires that water providers develop written policies prioritizing development that includes affordable housing to low-income households (Government Code Section 65589.7). The City passed Resolution 2006-508 on August 8, 2006, adopting written procedures to uphold this legislation.

As shown in Table 4‑9 (DWR Table 4-3 Retail), projected water use for lower income households in the City’s water service area is included in the water use projections. A lower income household is defined as a household that has an income below 80 percent of the area median income (AMI), adjusted for family size. The projected water demands shown in Table 4-5 and Table 4-6 include water use for single family and multi-family residential housing needed for low-income households, as identified in the City’s Housing Element.

The City’s 2023-2031 Housing Element, adopted in December 2023, identified the existing distribution of lower-income households in the City of Modesto as follows:
• Low Income (51–80% AMI): 18.4 percent of all households • Very Low Income (31–50% AMI): 12.1 percent of all households • Extremely Low Income (0–30% AMI): 11.5 percent of all households Are Future Water Savings Included in Projections? Drop down list (y/n)
No
If "Yes" to above, state the section or page number, in the cell to the right, where citations of the codes, ordinances, or otherwise are utilized in demand projections are found.

Optional Suppliers may complete Optional Submittal Table 4-4 R to quantify the expected savings.

Are Lower Income Residential Demands Included In Projections? Drop down list (y/n)
Yes
Optional If the method for accounting Lower Income Residential Demands has been included, provide page number where this accounting can be found. Refer to Section 4.2.6 DWR NOTES: Additional guidance is provided in Appendix K. #20..
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Therefore, totaling these three income distributions, approximately 42 percent of existing households within the City are lower income households.
3 The City assumes that lower income households will continue to represent approximately 42 percent of the City’s total residential customers through 2050 while recognizing that the percentage of lower income households is subject to change as demographic changes may occur. With this assumption, the projected water demand from lower income households will be approximately 16,926 AFY of residential water use by 2050.

4.3 DISTRIBUTION SYSTEM WATER LOSSES
System losses are the difference between the actual volume of water treated and delivered into the distribution system and the actual metered consumption. Such apparent losses are always present in a water system due to pipe leaks, unauthorized connections or use, faulty meters, unmetered services such as fire protection and training, and system and street flushing.

4.3.1 Water Loss Audits
Urban retail water suppliers are required to submit water loss audits of their potable water systems to DWR on an annual basis.4 The City uses the AWWA Water Audits and Loss Control Programs method to annually evaluate its distribution system losses for each of its public water systems (PWSs). A water audit is an accounting exercise that tracks all sources and uses of water within a water system over a defined period. The City conducts these water audits on a fiscal year basis, covering the period from July 1st through June 30th of the following year.

Table 4-10 (DWR Table 4-5 Retail) summarizes the City’s status in submitting its AWWA water audits for the last five years starting with the 2020 reporting period. Copies of the City’s water audit worksheets over the past five years are provided in Appendix E and can also be found on DWR’s Water Use Efficiency Data (WUEdata) Water Audit Report Data website at https://wuedata.water.ca.gov/awwa_plans.

Because the Salida PWS is permanently interconnected to the City of Modesto main system, a separate water loss audit is not prepared. Instead, Salida has been included within the main system’s water loss audit since the inception of Modesto’s water loss audit program.

As MID is a water wholesaler and not an urban retail water supplier, MID is not required to submit AWWA water loss audits or meet water loss standards.
3 City of Modesto. December 2023. Housing Element 2023-2031. Table 17: Household Income Level by Tenure, 2019. Data is from U.S. Department of Housing and Urban Development (HUD), Comprehensive Housing Affordability Strategy (CHAS) American Community Survey (ACS) tabulation, 2015-2019. 4 For additional details on water loss audit requirements, refer to California Code of Regulations (CCR) Title 23, Division 2 Department of Water Resources, Chapter 7 Water Loss Audits and Water Loss Control Reporting, §638.2.

Audit Standards and Frequency.
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Joint 2025 Urban Water Management Plan
May 2026
Table 4-10. Water Loss Audit Reporting (DWR Table 4-5 Retail) Public Water System ID #
Reported in Table 2-1 R Reporting Period Submitted to DWR Water Loss Audit Program (yes/no) 2020 Yes
2021 Yes
2022 Yes
2023 Yes
2024 Yes
2020 No
2021 No
2022 No
2023 No
2024 No
2020 Yes
2021 Yes
2022 Yes
2023 Yes
2024 Yes
2020 Yes
2021 Yes
2022 Yes
2023 Yes
2024 Yes
2020 Yes
2021 Yes
2022 Yes
2023 Yes
2024 Yes
2020 Yes
2021 Yes
2022 Yes
2023 Yes
2024 Yes
2020 Yes
2021 Yes
2022 Yes
2023 Yes
2024 Yes
2020 Yes
2021 Yes
2022 Yes
2023 Yes
2024 Yes
CA5010035
Central Turlock
DWR NOTES: Suppliers will provide a link to the WUEdata submittals of their Water Loss Audit Reports.

NOTES: (a) Because the Salida PWS is permanently interconnected to the City of Modesto main system, a separate water loss audit is not prepared. Instead, Salida has been included within the main system’s water loss audit since the inception of Modesto’s water loss audit program.

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4.3.2 Water Loss Standards
In November 2022, DWR and the State Water Board adopted water loss standards for urban retail water suppliers. The new regulation provides suppliers with volumetric standards that establish cost-effective levels of achievable water loss based on each supplier’s water system characteristics and budgets.

Beginning in January 2028, suppliers must meet their individual volumetric real loss standards based on a three-year compliance period of the Years 2025, 2026, and 2027. Individual apparent water loss standards must also be met at the same 2028 compliance date.

Water loss standards have been established for four of the City’s PWSs, including the City of Modesto main system (including Salida), Grayson, Del Rio, and South Turlock. Table 4-11 (DWR Table 4-6 Retail) summarizes the PWS’s real and apparent water losses for 2025 compared to their respective 2028 water loss standards. Water losses for these four PWSs are based on their respective AWWA water loss audits from the 2024-2025 fiscal year. These most recent water loss audits show that:
• The City of Modesto main system’s real water loss is below the applicable 2028 standard, indicating compliance with the real water loss requirement. The apparent water loss is slightly above the applicable 2028 standard.
• The Grayson PWS’s real water loss and apparent water loss are below the applicable 2028 standards, indicating compliance with these water loss requirements. • The Del Rio and South Turlock systems’ real water loss and apparent water loss currently exceed the 2028 standard.

Water loss standards do not apply to some of the City’s smaller PWSs, including Ceres (Walnut Manor), North Turlock, and Central Turlock, as these PWSs serve less than 200 connections. The Salida PWS also does not have separate water loss standards, as it is permanently interconnected and geographically adjacent to the City of Modesto main system. Therefore, the Salida PWS is combined with the main system for the purposes of water loss audits and water loss standards.

The Grayson, Del Rio, and South Turlock PWSs each serve more than 200 connections. Unlike Salida, these three PWSs are not geographically adjacent to the City of Modesto main system and are hydraulically separate. As these PWSs were included in the City’s Urban Water Use Objective (UWUO) calculations, the Grayson, Del Rio, and South Turlock PWSs each have a separate water loss standard.5 The City will continue to implement water loss control measures to meet the applicable water loss standards by the 2028 compliance deadline. The City’s programs to assess and manage water loss are discussed further in Chapter 9.

It should be noted that the number of connections shown in Table 4-11 include both active and inactive connections, and therefore this value may not match the number of active connections shown in Table 2-1 (DWR Table 2-1 Retail).
5 For additional details on water loss control requirements, refer to California Code of Regulations (CCR) Division 3 State Water Resources Control Board and Regional Water Quality Control Boards, Chapter 3.5 Urban Water Use Efficiency and Conservation, Article 2 Water Loss Performance Standards for Urban Retail Water Suppliers. #20..
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Table 4-11. Progress Towards 2028 Water Loss Standard (DWR Table 4-6 Retail) 2028 Real Water
Loss Standard per
Unit per day
Units for Real Water
Loss
Drop down list
Number of Units
(Connections or Miles
corresponding with
units selected)
Volume of Total Real
Loss
(from AWWA Water Loss
Audit)
(AF)
2028 Apparent Water Loss
Standard per Unit per Day
Units for Apparent
Water Loss
Number of
Connections
Volume of Total Apparent
Loss
(from AWWA Water Loss
Audit)
(AF)
CA5010010
City of Modesto Yes 16
Gallons per Service
Connection per Day
(GPSCD)
75,123 1,027 12.2 13.4
Gallons per Service
Connection per Day
(GPSCD)
75,123 1,222 14.5
CA5010005
Salida No N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
CA5010031
Ceres (Walnut
Manor)
No N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
CA5010033
Grayson Yes 13.7
Gallons per Service
Connection per Day
(GPSCD)
278 1.2 4.0 13
Gallons per Service
Connection per Day
(GPSCD)
278 3.2 10.2
CA5010029
Del Rio (Hillcrest) Yes 17.3
Gallons per Service
Connection per Day
(GPSCD)
408 40.0 87.5 37
Gallons per Service
Connection per Day
(GPSCD)
408 17.8 38.8
CA5010034
North Turlock No N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A CA5010023
South Turlock Yes 14.2
Gallons per Service
Connection per Day
(GPSCD)
336 12.2 32.3 9.1
Gallons per Service
Connection per Day
(GPSCD)
336 3.9 10.5
CA5010035
Central Turlock No N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A NOTES: Number of service connections and losses are from the water system's respective 2024-2025 fiscal year AWWA Water Loss Audit. Number of service connections includes both active and inactive connections. Refer to Section 4.3.2 for explanation of why some PWSs do not have a water loss standard.

Apparent Water Loss
Did the Water Board
Calculate a Water Loss
Standard for this Public
Water System? (y/n)
If no, Supplier will not
complete this row.

Real Water Loss
DWR NOTES: Units of measure (AF, CCF, MG) for Water Loss MUST remain consistent with units reported in Submittal Table 2-3. The units reported in Submittal Table 2-3 are used in this table's calculations.

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4.4 CLIMATE CHANGE CONSIDERATIONS
Climate change has the potential to alter local climatic patterns and meteorology. This potential alteration may impact the City and MID’s future water demand and use patterns. In general, climate change is expected to increase water demand for irrigation and increase the year-to-year demand variability. This increase in demand is the result of increased temperatures (which increases evapotranspiration) and more variability in precipitation (which impacts supply availability and reliability). Also, natural disasters such as wildfires, droughts, and floods are expected to increase in both frequency and intensity.

Current and ongoing demand management measures and water conservation by the City’s water customers, discussed in Chapter 9, could mitigate the effects of climate change on water demands.

The City and MID will continue to monitor the impacts of climate change on its water demands and on regional groundwater and surface water conditions. Updated climate and hydrologic information will be incorporated into future Joint UWMP updates. The potential impacts of climate change on the City and MID’s water supplies are described in Chapter 6.
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May 2026
CHAPTER 5
SB X7-7 Baselines, Targets, and 2020 Compliance
In November 2009, SB X7-7, the Water Conservation Act of 2009, was signed into law as part of a comprehensive water legislation package. The Water Conservation Act addressed both urban and agricultural water conservation. The legislation set a goal of achieving a 20 percent statewide reduction in urban per capita water use by December 31, 2020 (i.e., “20 by 2020”). In order to meet the urban water use target requirement, each retail supplier was required to determine its baseline water use, as well as its target water use for the Year 2020. Water use is measured in GPCD.

This chapter provides a review of the calculation of the City’s 2020 urban water use target and demonstrates that the City has achieved its 2020 target reduction.

Since MID is a water wholesaler and does not serve urban water users directly, it is not required to establish and meet any water conservation targets associated with the Water Conservation Act of 2009.

However, MID fully supports its water retailers in achieving their water conservation targets. A discussion of MID’s programs and policies for water conservation is provided in Chapter 9 Demand Management Measures (DMMs).

The City, as a water retailer, is required to report its compliance with the 2020 urban water use target as of 2020. The 2020 urban water use target has since been superseded by the establishment of Urban Water Use Objectives as part of the Making Conservation a California Way of Life regulation adopted on July 3, 2024. Starting in 2024, the City’s Urban Water Use Objective is calculated and reported annually through a separate process, and therefore, the City does not compare its 2025 water use with its 2020 target. Additional information on the City’s water conservation practices and objectives is included in Chapter 9.

5.1 OVERVIEW AND BACKGROUND
The City’s compliance with SB X7-7 was first addressed in the City and MID’s Joint 2010 UWMP. The City’s baseline per capita water use was determined, and urban water use targets for 2015 and 2020 were established and adopted. Actual water use data and population estimates were used to calculate daily per capita water use.

SB X7-7 required each urban water retailer to determine its baseline daily per capita water use over a 10-year or 15-year baseline period. In its 2015 UWMP, the 10-year baseline period that the City selected was verified to be 1999 through 2008. The City calculated its baseline water use and water use targets on an individual reporting basis in accordance with SB X7-7 legislation requirements and DWR Methodologies for Calculating Baseline and Compliance Urban Per Capita Water Use (2016) (DWR Methodologies).

Details of the specific methodology used to calculate the City’s 2020 water use target are documented in the City and MID’s Joint 2020 UWMP.

5.2 2020 DAILY PER CAPITA WATER USE COMPLIANCE
In its Joint 2020 UWMP, the City calculated its actual 2020 water use for the 2020 Calendar Year in accordance with the DWR Methodologies document. As shown in Table 5-1, urban per capita water use in 2020 was 175 GPCD, which is below the confirmed 2020 water use target of 228 GPCD. Therefore, the City met its 2020 final water use target. Water use in 2020 in the City’s service area was reduced as compared to baseline years as a result of increased water conservation efforts by the City and its customers.
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Table 5-1. SB X7-7 2020 Target Progress (DWR Table 5-1)

5.3 REGIONAL ALLIANCE
The City has chosen to comply with the requirements of SB X7-7 on an individual basis. The City has elected not to participate in a regional alliance.

Actual 2025 GPCD
(From SB X7-7
Compliance Form)
Did Supplier meet
the 2020 Target in
2025?
No Individual
Target
228 175 Yes NA
Did Supplier
Achieve Targeted
Reduction for
2020?
Actual 2020
GPCD
2020 Target
Regional
Alliance Target
or Individual
Target?
Drop down list
DWR NOTES:

Suppliers calculating a 2025 GPCD will need to complete and submit SB X 7-7 Compliance Tables to verify the use of SB X7-7 Methodologies.

Suppliers that were part of a merger or consolidation since 2020 see Chapter 5 and Appendix P for guidance.

NA=Not Applicable
Check the box if the Supplier was not an Urban Water Supplier during or before the 2020 UWMP reporting cycle.

Proceed to the next table.

Only for suppliers that did not meet
the Target in 2020
See DWR NOTES below. Was Supplier part of
a merger or
consolidation since
2020?
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May 2026
CHAPTER 6
Normal-Year Water Supply Characterization
This chapter describes the City and MID’s water supply portfolio. Currently available water supplies, as well as future anticipated water supplies, are described and quantified. The management of each water supply is discussed, along with the measures that the City and MID have taken to develop planned sources of water.

Anticipated availability of the City and MID’s water supplies under a normal water year is provided in this chapter. The availability of the City and MID’s water supplies under a single dry year and a drought lasting five years, as well as more frequent and severe periods of drought, are described in Chapter 7 of this Joint UWMP, along with their associated basis of estimates.

6.1 OVERVIEW OF WATER SUPPLIES
The City currently uses a conjunctive water use strategy with two primary water sources to meet potable water demands within the City’s service area. These include:
• Surface water from the Tuolumne River via the Modesto Reservoir, which is treated at MID’s MRWTP, and purchased on a wholesale basis from MID
• Local groundwater pumped from City wells located throughout the City’s service area City residents within the contiguous service area north of the Tuolumne River (including North Modesto, Salida, and Empire) generally rely on treated surface water supply from MID year-round and are also supplemented with groundwater. Water demands for the contiguous service area located south of the Tuolumne River (South Modesto) and the City’s outlying service areas are met entirely with groundwater supply year-round.

Prior to 1995, all municipal and industrial (M&I) water demands in the City were met from groundwater.

Beginning in the 1940s, increased water demands resulting from growth, along with periodic drought conditions, contributed to a reduction in groundwater levels and created a cone of depression under the City. This cone of depression, combined with increasingly stringent federal and state water quality requirements, prompted a 1983 study of the City’s groundwater supply. This study recommended a conjunctive water use program that would supplement the City’s groundwater supply with treated surface water from the Tuolumne River. Following the recommendations from the study, the City, MID and the former Del Este Water Company1formed a partnership to use a portion of MID’s surface water supplies for municipal water use. In 1995, treated surface water deliveries to the City began from the MRWTP, with an initial Phase 1 treatment capacity of 30 million gallons per day (MGD).

6.2 SURFACE WATER
This section describes the treatment and delivery of MID’s surface water supply to the City. The City does not have a separate surface water supply and relies on treated surface water purchased from MID on a wholesale basis. A discussion of the wholesale water supply to the City, including the agreements governing the treated surface water deliveries from MID, is provided in Section 6.3. 1 In 1995, the City acquired the Del Este Water Company. #20..
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6.2.1 Surface Water Supply for MID
MID is primarily an agricultural water supplier that provides irrigation water to approximately 3,100 irrigation accounts, with an average of 20 acres per account. 2 MID serves a gross irrigation service
area of approximately 103,733 acres; however, MID’s irrigated acreage may vary in any given year.

In 2024, a total of 66,218 acres were irrigated within MID’s service area, with approximately 61,757 acres of land receiving surface water from MID.
2 In addition to its irrigation accounts, MID also provides treated surface water to the City’s contiguous service area north of the Tuolumne River (North Modesto, Salida, and Empire).

Together with the Turlock Irrigation District (TID), MID holds senior rights to water from the Tuolumne River. The 1,880-square mile (sq mi) Tuolumne River watershed extends to the high Sierra Nevada Mountains, and the river flows to its confluence with the San Joaquin River approximately 10 miles west of Modesto. Most of the water in the Tuolumne River comes from snowmelt, with peak runoff flows occurring from April through July during which time over 60 percent of the annual flow takes place. Within the lower Tuolumne River watershed, MID and TID operate the Don Pedro Reservoir with a maximum storage capacity of 2,030,000 AF. MID’s annual diversion from the Tuolumne River is approximately 283,874 AF of water (median from 1995 to 2024). Of that amount, approximately 29,722 AF (average from 1995 to 2024) is delivered to the MRWTP for treatment and delivery to the City.2 Snowmelt from the central Sierra Nevada is of excellent quality. Surface water within MID’s Modesto Reservoir, which is the reservoir that directly supplies the MRWTP, has an average total dissolved solids (TDS) concentration of less than 25 milligrams per liter (mg/L).2 Other water quality constituents that impact agricultural and domestic water use are also very low or negligible. Also, the surface water quality is fairly consistent from year to year. As runoff from agricultural and developed land is introduced into the lower part of the river, the overall water quality is influenced.

6.2.2 Modesto Regional Water Treatment Plant
The MRWTP is located adjacent to MID’s Modesto Reservoir and treats surface water diverted from the Tuolumne River for the City’s municipal use. Treated surface water from the MRWTP is delivered to MID’s terminal reservoir facilities (two 5 MG storage tanks and an associated booster pump station located on the east side of the City). Water delivered to this facility is subsequently pumped into the City’s water transmission/distribution system and is introduced into the broader distribution system via a series of City-owned turnouts along the transmission mains. Portions of the transmission main system are owned by MID and some owned by the City.

The MRWTP is a conventional treatment facility owned and operated by MID, which provides flocculation, sedimentation, and filtration, along with ozonation for primary disinfection. The original Phase 1 MRWTP began operations in 1995 with an annual average design capacity of 30 MGD (33,600 AFY). The Phase 1 MRWTP has a maximum functional capacity of 42.5 MGD, which helps to meet maximum day demands of the City’s contiguous service area north of the Tuolumne River; however, MRWTP is permitted by the State to produce up to 45 MGD.
2 Source: Modesto Irrigation District. March 2025. Draft 2025 Agricultural Water Management Plan. #20..
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In October 2005, MID and the City approved the Amended and Restated Treatment and Delivery Agreement (ARTDA), which set forth the MRWTP Phase Two Expansion project that would add 30 MGD of treatment capacity. The MRWTP Phase Two Expansion project included construction of a new parallel treatment process consisting of low-pressure membranes, ozone disinfection system, a dissolved air flotation thickener and a new Supervisory Control and Data Acquisition (SCADA) system.

Substantial completion of the MRWTP Phase Two Expansion project was reached in October 2015, and the project was accepted as complete by the MID Board of Directors in May 2016. With this expansion, the total annual average design capacity of the MRWTP is 60 MGD, supporting a maximum annual supply of up to 67,200 AFY. As demand within the City’s contiguous service area increases, it is anticipated that the City will gradually increase the use of surface water that is now available from the Phase 2 Expansion project.

6.3 PURCHASED OR IMPORTED WATER
As discussed in Section 6.2, the City purchases treated surface water supply from MID in accordance with the ARTDA. MID does not purchase wholesale water supplies, and a discussion of MID’s surface water supply was provided in Section 6.2 above.

Historically, annual treated surface water deliveries to the City have been relatively consistent, with groundwater pumping by the City varying as needed to meet water demands. However, during the recent droughts in both 2012 through 2016, and 2021 through 2022, MID reduced surface water deliveries to both its agricultural customers and to the City.2

6.3.1 Treatment and Delivery Agreement
The original TDA, enacted in 1992, established the delivery of treated surface water to the City’s contiguous service area north of the Tuolumne River. It obligated MID to deliver up to 33,600 AFY of treated surface water to the City, commencing on May 1 and ending the following April 30 during normal years. In 1995, the City purchased the Del Este Water Company and, along with it, their proportional share of treated surface water as defined in the TDA3.

6.3.2 Amended and Restated Treatment and Delivery Agreement As discussed above, MID and the City approved the ARTDA in October 2005. This agreement supersedes the original TDA and sets forth the terms and conditions for the delivery of up to 67,200 AFY of treated water to the City from the expanded MRWTP. The increased capacity provided by the MRWTP Phase Two Expansion project will allow the City to serve more surface water as demands increase, thereby reducing dependence on groundwater.
3 In 1995, the City purchased the Del Este Water Company water systems in Empire, Salida, Waterford, Hickman, Grayson, Del Rio, and portions of Ceres and Turlock. In 2015, the City subsequently sold the Waterford and Hickman water systems to the City of Waterford.
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6.3.2.1 Surface Water Allocation
The ARTDA includes a formula to reduce deliveries in drier than average years based on the number of inches of water allocated to MID’s agricultural customers. The ARTDA specifies a maximum delivery of 42 inches of water, or the amount calculated as (y/42) times 67,204.2 AFY4, whichever is less (where y is the actual number of inches of water allocated by MID to agricultural water users for the Domestic Water Year5). The allocation formula is as follows:
𝑦
42 × 67,204.2 = 𝑥
where
y is the number of inches of water allocated to MID’s agricultural customers x is the calculated amount of water to be delivered to the City in that particular year in AF Although the ARTDA specifies a formula for allocating water during shortages, the reduction in supply is not determined until the time of the shortage (ARTDA, Section 17.2 Formula for Water Allocation). While the formula is based on the total capacity available with the completion of the MRWTP Phase Two Expansion, the actual supply quantity available will be based on the City’s increase in demand and will need to conform to requirements of the ARTDA. A copy of the ARTDA is provided in Appendix F.

The ARTDA also provides the opportunity for the City to purchase additional water from MID (at a higher cost) or to exchange groundwater meeting the requirements of the ARTDA for agricultural use for treated surface water during drought years if such supplemental water supplies are available. Additional discussion regarding the availability and reliability of treated surface water supply from MID in dry years is provided in Chapter 7.

Section 6.1 of the ARTDA states that “In designing, constructing, operating and maintaining the First Expansion Facilities, [MID] also shall comply with applicable provisions of the [Subsequent Environmental Impact Report on the First Expansion Facilities], the related mitigation monitoring plan, and Urban Water Management Plan.” The ARTDA also defines the UWMP to be “as the same may be adopted by the parties from time to time.”
Notwithstanding any statement directly or arguably to the contrary in this plan, the 67,204.2 AF of water to be provided to the City by MID pursuant to the ARTDA is not altered, reduced or limited by the provisions of this plan.
4 As described in the ARTDA, upon completion of MRWTP Phase Two Expansion, the treated water quantity shall be changed from 33,602.1 AFY to 67,204.2 AFY. These are the exact contractual supply volumes and are rounded to 33,600 AFY and 67,200 AFY, respectively, throughout this plan. 5 The Domestic Water Year is defined in the ARTDA (Section 4.22) to be May 1 through April 30 (e.g., the 2020/2021 Domestic Water Year extends from May 1, 2020 through April 30, 2021). #20..
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6.4 GROUNDWATER
The City relied exclusively on groundwater to meet water demands until the introduction of treated surface water in 1995. The City currently has 76 active groundwater wells in both the contiguous and outlying service areas, including wells that require blending. The total well production capacity is approximately 59,700 gallons per minute (gpm) or 86 MGD. 6 The City also operates a series of non-potable irrigation wells at City parks. Generally, these facilities were originally constructed as potable supply wells and were later converted to non-potable irrigation use as water quality deteriorated. Retaining these wells for irrigation has helped the City offset potable water demand by reducing reliance on treated drinking water for park irrigation.

MID pumps groundwater to supplement water supplies to agricultural customers but does not pump and deliver groundwater to urban suppliers (i.e., the City of Modesto). The City and MID’s groundwater supplies are discussed separately below.

6.4.1 Groundwater Supply for the City
The City uses groundwater pumped from the San Joaquin Valley Groundwater Basin as a major source of supply. The City’s service area spans three subbasins: the Modesto Subbasin north of the Tuolumne River, the Turlock Subbasin south of the Tuolumne River, and the Delta-Mendota Subbasin west of the San Joaquin River that provides groundwater to the Grayson service area. Figure 6-1 illustrates the location of the City’s water service areas in relation to the boundaries of the three underlying groundwater subbasins.

Most of the City of Modesto’s contiguous service area lies within the Modesto Subbasin, but the southern portion extends into the Turlock Subbasin. The residents within the City’s contiguous service area north of the Tuolumne River generally rely on treated surface water supply from MID year-round and are supplemented with groundwater to meet increased water demands in the summer months. Water demands from the City’s contiguous service area located south of the Tuolumne River (South Modesto) and the outlying service areas are met with groundwater supply year-round.

The following sections further describe the City’s groundwater supply, including a description of the groundwater basin and subbasins, the City’s estimated groundwater operational yield, groundwater management activities, and historical and projected groundwater use.

6.4.1.1 Groundwater Basin Description
The City’s service area relies on groundwater pumped from three of the nine subbasins within the San Joaquin Valley Groundwater Basin. Key characteristics of these groundwater subbasins are summarized in Table 6-1. Subbasin descriptions provided below are from the respective Subbasin’s Groundwater Sustainability Plans (GSPs).
6 City Excel spreadsheet from January 2026 titled ‘Well Evaluation 1-21-2026’. #20..
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Table 6-1. Groundwater Subbasin Characteristics and Service Areas(a) Subbasin Name DWR Subbasin No. General Location Surface Area City Water Service
Areas(b)
Modesto 5-22.02
North of
Tuolumne River,
South of Stanislaus
River
245,250 acres
(383 sq mi)
North Modesto
South Modesto(c)
Salida
Empire
Del Rio
Turlock 5-22.03
South of
Tuolumne River,
North of Merced
River
348,160 acres
(544 sq mi)
South Modesto
Turlock
North Ceres
Ceres (Walnut Manor)
Delta-Mendota 5-22.07 West of the
San Joaquin River
765,000 acres
(1,195 sq mi) Grayson
(a) Based on information published in each Subbasin’s respective GSP:
• Modesto Subbasin Groundwater Sustainability Plan (Revised July 2024) • Turlock Subbasin Groundwater Sustainability Plan (Revised July 2024) • Groundwater Sustainability Plan for the Delta-Mendota Subbasin (July 2024) (b) See Figure 6-1 for locations of the City water service areas in relation to the groundwater subbasin boundaries. (c) The City’s water distribution system in the contiguous service area is interconnected between North and South Modesto areas; groundwater produced in the Modesto Subbasin (North Modesto) can be delivered to South Modesto. sq mi = square miles
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0 1 2
Scale in Miles
Notes:

1. Sphere of influence boundary obtained from the City on 11/6/2014.

2. City limit boundary based on County GIS data downloaded on October 6, 2014.

Stanislaus County
Merced County

STANISLAUS R IVER
LAIRD
SLOUGH

SANJOAQUINRIVER

DRY CREEK

TUOLUMNE RIVER

STANISLAUS RIVER
5 108
165
99 33
132 132
Grayson
Del Rio
North Turlock
Central Turlock
South Turlock
Ceres (Walnut Manor)
Figure 6-1
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Groundwater Subbasins
Modesto Subbasin
Turlock Subbasin
Delta-Mendota Subbasin
Contiguous Service Area
Outlying Service Area
City Limits
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Groundwater in the Modesto Subbasin occurs under unconfined, semi-confined, and confined conditions.

Three principal aquifers were defined in the Modesto Subbasin’s GSP. The Corcoran Clay, which underlies the western portion of the Modesto Subbasin, is the primary aquitard and is used to delineate the three principal aquifers. The Corcoran Clay thins beneath the City and is not present beneath eastern portions of the City. East of the Corcoran Clay, the aquifer system transitions from unconfined conditions to semiconfined conditions with depth.

The principal aquifers in the Modesto Subbasin consist of: (1) the Western Upper Principal Aquifer, an unconfined aquifer located above the Corcoran Clay; (2) the Western Lower Principal Aquifer, a confined aquifer below the Corcoran Clay; and (3) the Eastern Principal Aquifer, an unconfined to semi‑confined aquifer system located east of the Corcoran Clay. The Corcoran Clay underlies the southwestern portion of the Modesto Subbasin at depths ranging from 150 to 250 feet.7 The City’s contiguous service area north of the Tuolumne River uses groundwater wells within all three principal aquifers of the Modesto Subbasin.

Similar to the Modesto Subbasin, the Turlock Subbasin also has three defined principal aquifers in its GSP, also delineated by the Corcoran Clay aquitard in the western portion of the Turlock Subbasin. The three principal aquifers include the Western Upper Principal Aquifer (unconfined above the Corcoran Clay), the Western Lower Principal Aquifer (confined below the Corcoran Clay), and the Eastern Principal Aquifer (unconfined to semi-confined east of the Corcoran Clay). In the western Turlock Subbasin, where the Turlock and Ceres outlying water service areas overly, the Corcoran Clay ranges from 90 to 240 feet below ground surface (bgs) and varies in thickness from 10 feet to 110 feet.8 Previous groundwater studies performed by the City have subdivided the Modesto and Turlock Subbasin’s aquifer systems into different zones based on different depths and water chemistries – including shallow, intermediate, and deep aquifer zones. These distinctions are used by the City when referring to production well completion depths in its service area, and are as follows:
• The “shallow aquifer” includes the Riverbank and Upper Turlock Lake Formations as well as the Corcoran Clay (where present). Shallow wells are completed within these aquifer zones. • The “intermediate aquifer” includes the Lower Turlock Lake Formation. Intermediate wells are completed in this aquifer zone.
• The “deep aquifer” consists of groundwater yielding sediments beneath the Lower Turlock Lake Formation. The deep aquifer includes the Laguna Formation and deeper sedimentary deposits. Deep wells are completed in these zones.9
Groundwater in the Delta-Mendota Subbasin consists of two primary aquifers as defined in its GSP: an Upper Aquifer, which issemi-confined and located above the Corcoran Clay aquitard, and a Lower Aquifer, which is confined and located below the Corcoran Clay. The Upper Aquifer ranges in depth across the Delta-Mendota Subbasin from approximately 150 feet bgs to over 550 feet bgs.10 The Lower Aquifer is generally of better water quality compared to the Upper Aquifer and therefore is more commonly used 7 Modesto Subbasin Groundwater Sustainability Plan. Revised July 2024. 8 Turlock Subbasin Groundwater Sustainability Plan. Revised July 2024. 9 City of Modesto. June 2021. City of Modesto. Wellfield Remedial Investigation/Feasibility Study. 10 Groundwater Sustainability Plan for the Delta Mendota Subbasin. July 2024. #20..
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for municipal supply. The Grayson outlying service area is located in the north-eastern area of the Delta-Mendota Subbasin, adjacent to the San Joaquin River.

The primary sources of groundwater recharge in all three subbasins are from deep percolation of applied irrigation water and from canals and stream/river seepage. Lesser groundwater recharge occurs from percolation from small streams and direct percolation of precipitation. As detailed in Section 6.5, the City also contributes to recharge efforts via stormwater percolation (i.e., rock wells, infiltration basins, and other recharge facilities).

6.4.1.2 Groundwater Level Trends
Groundwater levels in the Modesto Subbasin declined on average nearly 15 feet between 1970 and 2000.

However, since augmenting the City’s groundwater supply with treated surface water from the MRWTP beginning in 1995, the City observed that groundwater levels had started to rise, particularly in the Modesto Subbasin, as a result of reduced groundwater pumping. The Modesto Subbasin GSP includes hydrographs showing some City of Modesto wells within the Western Upper Principal Aquifer, Western Lower Principal Aquifer, and Eastern Principal Aquifer, which show water levels gradually rising from 1995 to 2000. During this five-year period, groundwater levels in some City wells rose by approximately 50 feet.
7 Since then, water levels shown in these City of Modesto wells appear to be relatively stable, with small declines during drought (about 10 to 20 feet) followed by recovery in post-drought years.

Groundwater levels in the Turlock Subbasin’s Western Principal Aquifer have been relatively steady throughout the GSP study period (1991 to 2015).8 The Turlock Subbasin showed less rebound in water levels from 1995 to 2000 (up to about 10 feet) compared to the Modesto Subbasin.

Groundwater levels in the Delta-Mendota Subbasin are influenced by the availability of imported surface water from the Central Valley Project delivered via the Delta-Mendota Canal, which is the primary source of imported water for agricultural users in the Subbasin. During the 2012-2016 drought, significant reductions in imported water and other surface water allocations led to groundwater levels reaching historic or near-historic low levels. Since 2016, groundwater levels have generally remained stable, with the exception of the 2020-2022 dry period, when reduced imported water deliveries again resulted in declining groundwater levels.10

6.4.1.3 Groundwater Quality
The City actively monitors water quality in all its wells to ensure that observed concentrations remain below the maximum contaminant levels (MCLs). The City also monitors certain unregulated emerging contaminants, such as per- and polyfluoroalkyl substances (PFAS), to comply with the U.S. Environmental Protection Agency’s Unregulated Contaminant Monitoring Rule (UCMR).

Several of the City’s active wells have treatment systems in place to remove various contaminants. The City has taken some production wells out of service due to various constituents of concern including arsenic, uranium, perchloroethylene (PCE), trichloroethylene (TCE), dibromochloropropane (DBCP), 1,2,3-Trichloropropane (TCP), and nitrate with levels exceeding drinking water regulatory MCLs. The City has approximately 46 inactive wells throughout its service area, 29 of which have been destroyed.11 These well abandonments have effectively reduced the City’s groundwater supply production capacity. 11 Per City Excel spreadsheet from January 2026, titled ‘Well evaluation 1-21-2026’. #20..
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As discussed in Section 6.4.1.1, the City generally categorizes its production wells in terms of depth in the aquifer, which include the shallow, intermediate, and deep aquifer zones. The City’s shallow wells are generally more impacted by water quality issues compared to the intermediate and deep wells, particularly with nitrate and uranium contamination.12 This has led the City to drill deeper wells to target areas of the aquifer with better water quality.

In general, the groundwater from the Turlock Subbasin, from which the South Modesto wells draw their water, is of relatively poor quality. In the South Modesto area, the City has a total of 12 wells, of which:
• Five are active wells that pump directly into the distribution system; • Six are blending wells that produce water of potable quality but do not meet all secondary MCL criteria for aesthetics. Water pumped from these blending wells is either blended on-site or pumped into storage tanks for blending with higher quality water so that the water quality of these blended supplies meets all applicable California Division of Drinking Water (DDW) primary and secondary MCL requirements; and • One is inactive due to high TCP concentrations.11
Three other wells in the South Modesto area have been abandoned and destroyed in the past 15 years due to elevated nitrate and uranium.

The City has also been monitoring salinity levels for the Grayson outlying service area located in the Delta-Mendota Subbasin, where salinity levels are generally elevated in both the Upper Aquifer and Lower Aquifer.

To minimize the City’s vulnerability to groundwater quality issues, the City has developed strategies to maintain and enhance its groundwater extraction capacity through a combination of well monitoring for early detection, constructing deeper wells, wellhead treatment, and blending programs. Additional information on the City’s planned groundwater well projects is provided in Section 6.9.2.

6.4.1.4 Groundwater Management
The Modesto, Turlock, and Delta-Mendota subbasins are not adjudicated. This means that there is no court-appointed “watermaster” to resolve groundwater pumping issues, and there are no current specific limits on the amount of groundwater that individuals and agencies may extract from the basins.

However, on September 16, 2014, Governor Jerry Brown signed into law a three-bill legislative package, composed of AB 1739 (Dickinson), SB 1168 (Pavley), and SB 1319 (Pavley), collectively known as the Sustainable Groundwater Management Act of 2014 (SGMA). SGMA legislation provides a framework for sustainable management of groundwater supplies by local authorities, with a limited role for state intervention when necessary to protect the resource. The legislation required the formation of GSAs and the development and implementation of GSPs for groundwater basins that are designated by DWR as medium or high priority. The State Water Board may intervene if local agencies do not form a GSA and/or fail to adopt and implement a GSP.
12 City of Modesto. June 2021. City of Modesto. Wellfield Remedial Investigation/Feasibility Study. #20..
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SGMA applies to basins or subbasins designated by the DWR as high- or medium-priority basins based on a statewide ranking that uses criteria including population and extent of irrigated agriculture dependent on groundwater. The final September 2019 Basin Prioritization results indicate that 94 of California's 515 groundwater basins and subbasins are high- and medium-priority basins. The final priorities assigned to the groundwater subbasins underlying the City’s service areas are shown in Table 6-2 below.

As shown, all three of the City’s underlying groundwater subbasins have been designated as high-priority basins, and the Delta-Mendota Subbasin has also been identified as critically overdrafted. The Delta-Mendota Subbasin is one of 21 basins designated by DWR as in a critically overdrafted condition, which triggered an accelerated timetable for SGMA compliance, including GSP development by 2020 and achievement of sustainability by 2040.

Table 6-2. Groundwater Basin Prioritization for Sustainable Groundwater Management Act(a) Basin Number Subbasin Name Priority Points Overall Subbasin Priority 5-22.02 Modesto 24.5 High
5-22.03 Turlock 26 High
5-22.07 Delta-Mendota 40 High; Critically
Overdrafted Basin
(a) California Department of Water Resources. Basin Prioritization. Accessed at https://water.ca.gov/Programs/Groundwater-Management/Basin-Prioritization, on April 2, 2026.

The Modesto Subbasin consists of two GSAs: the Stanislaus and Tuolumne Rivers Groundwater Basin Association (STRGBA) GSA and the County of Tuolumne GSA. The City of Modesto is one of seven member agencies of the STRGBA GSA, which also includes MID, Oakdale Irrigation District, City of Oakdale, City of Riverbank, City of Waterford, and Stanislaus County.

The two GSAs cooperatively developed the Modesto Subbasin GSP, which was first submitted to DWR in January 2022. The Final Revised Modesto Subbasin GSP was submitted to DWR on July 12, 2024. On February 27, 2025, DWR approved the Modesto Subbasin’s GSP. The Modesto Subbasin GSP is available at this website: https://www.strgba.org/plans-projects-reports/, and is incorporated herein by reference.

The Turlock Subbasin contains two GSAs: the West Turlock Subbasin GSA (WTSGSA) and the East Turlock Subbasin GSA (ETSGA). The City is one of ten member agencies of the WTSGSA, which also includes the City of Turlock, City of Ceres, City of Hughson, Merced County, Stanislaus County, Denair Community Services District, Delhi County Water District, Hilmar County Water District, and Turlock Irrigation District.

The WTSGSA also has two associate member agencies: the Keyes Community Services District, and the City of Waterford, which are located in the Modesto Subbasin to the north but operate the water system for the community of Hickman in the Turlock Subbasin.

The two GSAs cooperatively developed the Turlock Subbasin GSP, which was first submitted to DWR in January 2022. The Final Revised Turlock Subbasin GSP was submitted to DWR on July 12, 2024. On February 27, 2025, DWR approved the Turlock Subbasin’s GSP. The Turlock Subbasin GSP is available at this website: https://turlockgroundwater.org/gsp, and is incorporated herein by reference.

The Delta-Mendota Subbasin contains 23 GSAs. The Grayson water system is located within the West Stanislaus Irrigation District GSA, which developed the Northern and Central Delta-Mendota Regions GSP #20..
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along with seven other GSAs in November 2019. Although the City is not a member of the West Stanislaus Irrigation District GSA, it coordinates directly with Stanislaus County, which is a member of the West Stanislaus Irrigation District GSA.

The Delta-Mendota Subbasin GSAs submitted six GSPs in January 2020. In January 2022, DWR designated the 2020 GSPs as incomplete. In June 2022, the GSAs amended and resubmitted the six GSPs to DWR.

However, the 2022 GSPs were found to be inadequate by DWR in March 2023. As a result, DWR referred the subbasin to the State Water Board for further review under SGMA’s “state intervention” provisions.

When a groundwater basin is referred to the State Water Board, the Board can consider placing the basin on probation.

In response to DWR’s “inadequate” determination, the 23 GSAs collectively agreed to develop a single GSP for the Delta-Mendota Subbasin. In July 2024, the single Delta Mendota Subbasin GSP was completed and adopted by all GSAs within the Subbasin. State Water Board staff evaluated the single revised plan and concluded that it significantly improved groundwater management. Due to these improvements, State Water Board staff recommended against placing the Delta-Mendota basin on probation and recommended to return the basin to DWR for ongoing oversight while local agencies continue managing the subbasin.
13 As of April 2026, there are continued meetings with the State Water Board to determine next steps for Delta-Mendota Subbasin. The July 2024 Delta-Mendota Subbasin GSP is available at this website: https://deltamendota.org/final-gsp-documents/, and is incorporated herein by reference.

6.4.1.5 Groundwater Management Actions
As discussed in the 2024 Modesto Subbasin GSP, additional treated surface water supplies provided from the MRWTP Phase Two Expansion project (listed in the GSP as Urban Project 1, Growth Realization of Surface Water Treatment Plant Phase 2) will allow the City to further utilize available surface water to meet water demands in lieu of using groundwater in the Modesto Subbasin. The City plans to gradually increase the use of treated surface water supply from MID, particularly in normal and wetter years when full surface water allocations are available, to make use of this additional treatment capacity. The use of this treated surface water supply will benefit the Modesto Subbasin via in-lieu recharge and allow the City to preserve its groundwater supplies for use in drier years when surface water allocations are reduced.

Additional information on the City’s current and planned groundwater well projects is provided in Section 6.9.2.

6.4.1.6 Preliminary Operational Yield Estimate
In 2007, the City estimated that their preliminary operational yield from the three groundwater subbasins underlying the City’s service area is approximately 53,500 AFY. This preliminary operational yield was estimated based on historical groundwater pumping by the City from the Modesto, Turlock, and Delta-Mendota subbasins and was developed by City staff to maintain a minimum average groundwater elevation of 40 feet above mean sea level (ft msl).

The general conclusion of the City’s evaluation was that if the total, long-term average groundwater pumping quantity is held at or below 53,500 AFY, then stable groundwater levels will result at around 13 State Water Resources Control Board. February 2026. Accessed at https://waterboards.ca.gov/water_issues/programs/sgma/docs/delta-mendota/202603-dm-fact-sheet-en.pdf on April 2, 2026. #20..
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40 ft msl within and near the City’s contiguous service area. If groundwater pumping is significantly less than 53,500 AFY, groundwater levels will probably rise. This “in-lieu” groundwater banking allows for later use in dry periods and/or to meet future demands. Alternatively, if more than 53,500 AFY is extracted (e.g., during dry years), groundwater levels will probably decline. Actual annual groundwater pumping is expected to be less during normal or wet years and higher during dry years. Table 6-3 summarizes the long-term preliminary operational yield assumed for each subbasin. As shown in Table 6-3, the majority of the City’s operational yield allocation is within the Modesto Subbasin, which represents the subbasin that underlies the majority of the City’s water service area.

Table 6-3. City of Modesto’s Preliminary Operational Yield Assumed for Each Subbasin(a) Groundwater Subbasin Allocation, AFY
Modesto Subbasin 48,286
Turlock Subbasin 4,900
Delta-Mendota Subbasin 314
Total 53,500(b)
(a) As documented in the City’s Technical Memorandum titled “Discussion on Operational Yield for the 2005 Urban Water Management Plan”.
(b) Reduced to 51,500 AFY for this plan to account for removal of Hickman and Waterford’s groundwater production from the City of Modesto’s groundwater production.

This preliminary operational yield was developed when the City was still serving the Hickman and Waterford areas. Since that is no longer the case, the operational yield available for the City’s current service area has been updated to account for the groundwater pumped by Hickman and Waterford. The average combined groundwater production for Hickman and Waterford from 2000 through 2013 was approximately 2,000 AFY.

Therefore, the groundwater supply available to the City is assumed to be 51,500 AFY (i.e., reduced by 2,000 AFY to account for removal of Hickman and Waterford’s groundwater production from the City of Modesto’s groundwater production).

As shown in Sections 6.4.1.7 and 6.4.1.8 below, the City’s historical groundwater pumping and projected future groundwater pumping remain below the City’s total preliminary operational yield.

6.4.1.7 Historical Groundwater Pumping
The volume of groundwater pumped by the City over the past five years, including potable and non-potable uses, is summarized in Table 6-4 (DWR Table 6-1 Retail). Average annual groundwater pumping over the past five years has been approximately 25,748 AFY, which is well below the City’s estimated groundwater operational yield of 51,500 AFY. There were no limitations or challenges for obtaining groundwater during the past five years, as the City does not have any groundwater pumping restrictions.

In 2025, the City pumped 20,613 AF of groundwater for potable use, which represents approximately 41 percent of the City’s total annual water demand in 2025, with the remaining demand met by treated surface water from MID.
#20..
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Table 6-4. Groundwater Volume Pumped (DWR Table 6-1 Retail)

6.4.1.8 Projected Groundwater Use
The City plans to continue using groundwater to help meet peak demands and in dry years to make up for anticipated reductions in surface water deliveries. Generally, the City anticipates using surface water to meet approximately 70 percent of total demand during normal and wet years when surface water allocations are not reduced, with groundwater use meeting the remaining 30 percent. However, the actual proportion of surface water and groundwater use may differ due to various operational factors.

The City’s projected normal year groundwater use through 2050 is provided in Table 6-5. Projected potable groundwater use is based on the City’s projected total potable demands shown in Table 4-5 (DWR Table 4-2 Retail), and assuming that groundwater is used to meet 30 percent of the total potable demand.

Values are presented for planning purposes only, and actual groundwater use may vary due to hydrologic conditions, the timing of future development in the City’s service area and associated increases in water demand, and the City’s water system operational needs. The City has adequate well capacity and is not subject to any restrictions that would prevent it from using groundwater in excess of the volumes shown in Table 6-5. The City’s projected groundwater use shown in Table 6-5 remains well below the City’s estimated groundwater operational yield of 51,500 AFY (discussed in Section 6.4.1.6).

The City’s projected non-potable groundwater use is expected to remain relatively constant through 2050.

Groundwater Type
Drop Down List
May use each category
multiple times
Potable or
Non-Potable
(OPTIONAL)
Drop down list
Location or Basin Name 2021 (AF) 2022 (AF) 2023 (AF) 2024 (AF) 2025 (AF) Alluvial Basin Potable San Joaquin Valley
Groundwater Basin 23,588 28,050 22,589 24,573 20,613
Alluvial Basin Non-Potable San Joaquin Valley
Groundwater Basin
1,865 1,865 1,865 1,865 1,865
25,453 29,915 24,454 26,438 22,478
DWR NOTES:

Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3. This table identifies the unit of measure selected in Submittal Table 2-3.

NOTES: Non-potable irrigation well use is not metered. Annual non-potable use is estimated based on the irrigable area of individual parks served.

Total
Check the box if the Supplier does not pump groundwater.

Proceed to the next table.

Check the box if all or part of the groundwater described below is desalinated. (OPTIONAL) #20..
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Table 6-5 Projected Groundwater Use for City of Modesto Groundwater
Type
Potable or
Non-Potable
Location or
Basin Name
Projected Water Supply Volume, AF
2030 2035 2040 2045 2050
Alluvial Basin Potable(a) San Joaquin Valley
Groundwater Basin 16,590 17,256 17,943 18,654 19,317
Alluvial Basin Non-Potable(b)
San Joaquin Valley
Groundwater Basin 1,865 1,865 1,865 1,865 1,865
Total 18,455 19,121 19,808 20,519 21,182
(a) Projected potable groundwater use is based on the City’s projected total potable demands shown in Table 4-5 (DWR Table 4-2 Retail), and assuming that groundwater is used to meet 30 percent of the total potable demand. Actual groundwater use may vary, and the City is permitted to use a greater amount of groundwater than is shown in this table. (b) Projected non-potable groundwater use is expected to remain relatively constant through 2050.

6.4.2 Groundwater Supply for MID
MID owns and operates approximately 93 groundwater wells that are used to supplement surface water supply, particularly during consecutive dry years.
2 Of these, approximately 52 are deep production wells, with the remainder being drainage wells. Most of these deep production wells are located immediately adjacent to the canal system in MID owned rights-of-way. Drainage wells are relatively shallow (usually less than 100 feet deep) and are pumped during the irrigation season to control shallow groundwater in the western part of the District.

As shown in Table 6-6 (DWR Table 6-1 Wholesale), MID does not currently pump and deliver groundwater supply to urban suppliers (i.e., the City of Modesto), nor does it have plans to do so in future years.

Additional information on MID’s groundwater supply for its agricultural customers can be found in MID’s 2025 AWMP.

Table 6-6 Groundwater Volume Pumped (DWR Table 6-1 Wholesale) Groundwater Type
Drop Down List
May use each category
multiple times
Potable or NonPotable
(OPTIONAL)
Drop down list
Location or
Basin Name
2021 (AF) 2022 (AF) 2023 (AF) 2024 (AF) 2025 (AF)
0 0 0 0 0
Check the box if the Supplier does not pump groundwater.

Proceed to the next table.

Total
Check the box if all or part of the groundwater described below is desalinated. (OPTIONAL) #20..
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6.5 STORMWATER
The City and MID do not directly utilize, nor have plans to directly utilize, stormwater as a water supply.

However, the City does use stormwater to promote groundwater recharge via rock wells, infiltration basins, and newly developed underground storage and recharge facilities, with plans to further develop passive recharge opportunities. For the MID service area, groundwater recharge via urban stormwater flows is estimated to be a negligible amount of recharge.14 The City’s storm drain system has approximately 170 miles of storm drain lines and 25 pump stations.

Stormwater from the City’s drainage system is discharged to detention and retention basins, approximately 18 major outfalls to receiving waters (Tuolumne River or Dry Creek), MID laterals and drains, and approximately 9,500 rock wells. Approximately 40 percent of stormwater discharges to detention and retention basins, 20 percent to receiving waters (Tuolumne River or Dry Creek), 10 percent to MID laterals and drains, and 30 percent to rock wells.

The City partnered with the County and other public agencies to develop the Stanislaus County Multi-Agency Regional Storm Water Resource Plan (SWRP), which evaluates beneficial stormwater uses, specifically those that can augment groundwater supplies. The SWRP was completed in August 2019 and adopted by the City in January 2020. The SWRP serves as a guide for the City to identify, prioritize, and implement local, multi-benefit stormwater and dry weather capture projects.15 The City is currently implementing the Storm Drain Cross Connection Removal Project which aims to improve the capture, treatment, and infiltration of stormwater within the City of Modesto. As described in the Modesto Subbasin GSP, the project components use low impact development (LID) techniques including bio-retention planters, infiltration trenches, and underground retention basins within city parks for groundwater recharge. Additional benefits include the reduction of stormwater flows to the City’s wastewater treatment plant and sanitary sewer overflows, reduction of localized flooding, and improved water quality within Dry Creek and the Lower Tuolumne River. This project also includes the removal of failed dry wells and storm to sanitary sewer cross connections.16 The City’s potential future implementation of a managed aquifer recharge program, which could incorporate stormwater as a source, is described in Section 6.9.2.3. 14 Modesto Irrigation District. March 2026. Draft 2025 Agricultural Water Management Plan. Table 47 – Overall Water Balance for 2024.
15 Stanislaus County. Stanislaus Multi-Agency Regional Storm Water Resource Plan. Accessed at https://www.stancounty.com/publicworks/swrp/ on April 5, 2026. 16 Modesto Subbasin Groundwater Sustainability Plan. Revised July 2024. #20..
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6.6 WASTEWATER AND RECYCLED WATER
This section provides information on the City’s current and future wastewater and recycled water uses.

MID is not directly involved with the treatment of wastewater or the distribution of recycled water and does not have plans to do so in the future.

6.6.1 Recycled Water Coordination
The cities of Modesto, Turlock, and Ceres have historically worked together to identify regional opportunities for wastewater treatment and recycled water production. A feasibility study was completed in 2005 to analyze opportunities for recycled water use in the region (Northern San Joaquin Valley Water Reclamation Project Feasibility Study [RMC, 2005]). This work was further refined with completion of additional feasibility, alignment, and other studies in 2013 and 2015. Ultimately, the North Valley Regional Recycled Water Program (North Valley Program) was selected for implementation to regionalize recycled water use in Stanislaus County.17
The North Valley Program provides recycled water supply to the Del Puerto Water District (DPWD) for agricultural irrigation. Since the 1990s, DPWD has experienced a reduction in Central Valley Project (CVP) water deliveries due to drought conditions and regulatory restrictions imposed on CVP operations. The geographic proximity of DPWD to the City’s wastewater treatment facilities provides an opportunity for recycled water to supplement DPWD’s existing water supply and improve water supply reliability. The source of recycled water for the North Valley Program includes recycled water from the cities of Modesto and Turlock, which is delivered directly into the Delta-Mendota Canal (DMC). The DMC is used to convey the blended canal‑recycled water to users in the west side of Stanislaus County.

The first phase of the North Valley Program was completed in 2018 and delivers approximately 14,000 AFY of disinfected tertiary treated recycled water to DPWD. Per the City’s agreement with DPWD, the North Valley Program could produce and deliver up to 16,800 AFY (15 MGD) of disinfected tertiary treated recycled water. The North Valley Program projected future deliveries of up to 59,900 AFY of tertiary treated recycled water by 2045 to western Stanislaus County; however, actual quantities will be dependent on wastewater generated by the cities of Modesto and Turlock.

Although the North Valley Program would not provide a potable water offset directly to the City’s service area, the recycled water is used beneficially, improving regional water supply reliability, reducing reliance on CVP allocations and local groundwater, and supporting nearby agricultural land with long-term drought-proof water supplies.

6.6.2 Wastewater Collection, Treatment, and Disposal
The City’s wastewater service area is smaller than the City’s water service area. The City of Modesto’s wastewater treatment facilities collect wastewater from residences, commercial businesses, and industries within the City limit boundaries, as well as North Ceres, Empire, and unincorporated County islands within City limits.
18 The following sections discuss the wastewater collected and treated within the City’s water service area either by the City or by other agencies. 17 North Valley Regional Recycled Water Program Final Report, prepared by RMC and Carollo, May 2015. 18 City of Modesto. December 2016. Wastewater Treatment Master Plan. #20..
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6.6.2.1 Wastewater Collected and Treated by the City
Influent to the City’s wastewater treatment facilities consists primarily of domestic, commercial, industrial, food processing, and winery waste. Treatment of the City’s wastewater occurs at two locations:
the Sutter Avenue Primary Treatment Plant (located within the City’s water service area) and the Jennings Road Treatment Plant (located outside the City’s water service area). The Sutter Avenue Primary Treatment Plant provides pumping, screening, grit removal, flow measurement, primary clarification, and sludge digestion. The primary effluent is then pumped approximately seven miles to the secondary treatment plant (the Jennings Road Treatment Plant) for further treatment.

The Jennings Road Treatment Plant includes both secondary and tertiary treatment facilities. Secondary treatment includes biological treatment with fixed film reactors, recirculation, aerated recirculation, and oxidation ponds. Pursuant to NPDES Permit No. CA0079103, the City currently disposes of the secondary treated effluent and cannery waste19 via irrigation of approximately 2,500 acres of City-owned ranch lands. When physical or regulatory constraints prevent land application, the effluent is stored on-site.

Discharge of secondary effluent to City-owned ranch lands is limited by organic loading limitations of the NPDES permit and available acreage.

In 2010, the Jennings Road Treatment Plant phased in tertiary treatment with the completion of Phase 1A of its Tertiary Treatment Project, providing up to 2.3 MGD of tertiary treated water. The tertiary treatment process includes oxidation, de-nitrification, membrane filtration, and ultraviolet disinfection facilities.

Phase 2 of the Tertiary Treatment Project was completed in 2018 and added another 12.6 MGD of tertiary treatment capacity, bringing the facility in compliance with the City’s NPDES Permits for year-round discharge to the DMC (i.e., DPWD) and the San Joaquin River.

6.6.2.2 Wastewater Collected and Treated by Other Agencies The City’s water service areas that do not receive wastewater services from the City of Modesto include Salida, Grayson, Del Rio, and portions of Turlock. The wastewater collected and treated by other wastewater agencies are described below.

The Salida Sanitary District provides wastewater collection, treatment, and disposal for the unincorporated community of Salida and various customers located outside its boundaries, including BMC West Lumber Company, the former Modesto Tobacco and Candy, Vella Middle School, Flory Industries, the former Shell Lab site, and Gregori High School. The Salida Sanitary District operates its wastewater treatment plant on the northern edge of Stanislaus County, just south of the Stanislaus River (6200 Pirrone Road, Salida). The Salida Sanitary District’s Wastewater Treatment Plant processes approximately 1.2 MGD (as of 2023), approximately half of the plant’s total capacity of 2.4 MGD.20 The Grayson Community Services District provides wastewater collection and treatment services to the community of Grayson. The Grayson Community Services District’s wastewater collection and treatment 19 Historically, about 20 MGD of cannery wastewater with high concentrations of organic vegetable solids were sent to the primary treatment plant, causing the treatment plant to operate inefficiently. To address this problem, the Cannery Segregation Project was implemented in the late 1990s such that up to 40 MGD of wastewater from seasonal canneries is segregated and bypasses treatment. These cannery discharges are applied directly to City-owned ranch lands as a soil supplement.
20 Stanislaus Local Agency Formation Commission (LAFCO). April 2023. Municipal Service Review and Sphere of Influence Update for the Salida Sanitary District.
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system has a design flow capacity of 100,000 gallons per day. Any growth in the area would require significant upgrades to the system to increase the treatment capacity.

Wastewater collection and treatment in Del Rio is provided by both private septic systems and small packaged wastewater treatment plants. Generally, the newer areas on the east and northwest as well as the Country Club and nearby condominiums are likely to be served by packaged plants, while the older larger homes are served by private septic systems.

The Turlock Regional Water Quality Control Facility (RWQCF) receives wastewater from the City of Turlock, the community service districts of Keyes and Denair, and up to 2 MGD of primary treated wastewater from the City of Ceres. The RWQCF is designed to treat an average of 20 MGD and is currently treating an average influent flow of 10.7 MGD. The raw wastewater received at the Turlock RWQCF is a combination of domestic and industrial wastewater flows. The RWQCF produces disinfected tertiary treated water that meets Title 22 standards for unrestricted non-potable use. Final effluent from the RWQCF is discharged to the DMC as supply for DPWD under the North Valley Program.

Table 6-7 (DWR Table 6 2 Retail)summarizes information on wastewater collection within the City’s water service area in 2025. As described above, the City of Modesto owns and operates the Sutter Avenue Primary Treatment Plant and Jennings Road Treatment Plant, while most areas outside the City limits are served by other wastewater collection agencies. The City has limited data on wastewater collection outside of its wastewater service area but has provided information in Table 6-7 that is readily available or can be reasonably estimated.

Table 6-8 (DWR Table 6 3 Retail) presents the volume of wastewater treated within the City’s water service area in 2025 and its discharge methods. As discussed above, the City’s Sutter Avenue Primary Treatment Plant is located within the City’s water service area and provides primary treatment only.

Primary effluent from the Sutter Avenue Plant is pumped to the Jennings Road Treatment Plant, which produces both secondary and tertiary treated recycled water. The Jennings Road Treatment Plant also separately receives cannery wastewater effluent that does not pass through the Sutter Avenue Plant.

While the Jennings Road Treatment Plant is located outside the City’s water service area, it is included in Table 6-8 because it represents a continuation of treatment from the Sutter Avenue Primary Treatment Plant and is used to produce recycled water associated with flows originating within the City’s service area.

As shown in Table 6-8, the City does not use any recycled water within its water service area. All recycled water produced at the Jennings Road Treatment Plant is used outside of the City’s water service area.

Disinfected tertiary treated recycled water is exported to DPWD for agricultural irrigation via the DMC as part of the North Valley Program. Undisinfected secondary treated recycled water from the Jennings Road Treatment Plant is either used to irrigate City-owned ranch lands or stored in on-site ponds. In 2025, approximately 12,027 AFY of tertiary treated recycled water was provided to DPWD for agricultural irrigation, and approximately 8,304 AFY of undisinfected secondary treated recycled water was used for applications on City-owned ranch lands, for a total volume of 20,331 AFY. #20..
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Table 6-7. Wastewater Collected Within Service Area in 2025 (DWR Table 6-2 Retail) #20..
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Table 6-8. Wastewater Treatment and Discharge Within Service Area in 2025 (DWR Table 6-3 Retail) Treatment
Level
Drop down
list
Volume
(AF)
Treatment
Level
Drop down list
Volume (AF)
Treatment
Level
Drop down
list
Volume
(AF)
Treatment
Level
Drop down
list
Volume
(AF)
Treatment
Level
Drop down list
Volume (AF) Name of other
entity
City of Modesto WQCF,
Place ID 241146 No 22,771 22,771 - - - - 22,693
City of
Modesto
Jennings Road
Treatment
Plant
Other (provide name and ID
in "NOTES" field) No 26,323 26,323 - Tertiary 20,331 - - - 49,094 49,094 0 20,331 0 0 22,693
DWR NOTES:

Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3. This table identifies the unit of measure selected in Submittal Table 2-3.

IPR: Indirect Potable Reuse would have the treatment level of its end use requirement in the Level of Treatment drop-down.

Additional Guidance: See Appendix M, Section M.21 for detailed guidance on this table.

Water Recycled Outside
of UWMP Service Area
(enter data as applicable)
Effluent Discharge that
is not a Permitted
Recycled Water Use
(enter data as applicable)
Required Discharge for
Instream Flow
(enter data as applicable)
Delivered to Another Entity for Additional
Treatment
(enter data as applicable)
2025 Outcomes of Treated Wastewater
Check the box if no wastewater is treated or disposed of within the UWMP service area.

Proceed to the next table.

Does This
Plant Treat
Wastewater
Generated
Outside the
UWMP Service
Area?
(OPTIONAL)
Drop down list
Wastewater Treatment
Plant Name and Place ID
Number
Drop down list
Total 2025
Volume of
Water
Treated (AF)
NOTES: The City of Modesto WQCF is the City's Sutter Avenue Primary Treatment Plant. The treatment level for the WQCF is left blank, as DWR does not provide an option for primary treatment. The "Other" City of Modesto WWTP is the Jennings Road Treatment Plant. Treatment level is shown as tertiary for the Jennings Road Treatment Plant; however, the facility produces and discharges both tertiary and secondary treated recycled water.

The total wastewater volume reported includes the volume treated at the Sutter Avenue primary plant and the flows subsequently treated at the Jennings Road secondary plant (double counting occurs due to the table formatting). The Sutter Avenue plant provides primary treatment only. All primary effluent from the Sutter Avenue plant is sent to the Jennings Road plant (located outside the City's service area). The Jennings Road plant also separately receives cannery wastewater effluent that is not treated at the Sutter Avenue plant. The Jennings Road plant produces both tertiary treated recycled water and secondary treated recycled water for for use outside of the UWMP service area. Tertiary treated recycled water is provided to DPWD for agricultural irrigation (12,027 AFY in 2025), and secondary treated recycled water is used for application on City-owned ranch lands (8,304 AFY in 2025), for a total volume of 20,331 AFY as shown above.

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6.6.2.3 Wastewater in MID
MID is not directly involved with the treatment and discharge of wastewater. Therefore, Table 6-9 (DWR Table 6-3 Wholesale) has been intentionally left blank.

Table 6-9. Wastewater Treatment and Outcomes Within Service Area in 2025 (DWR Table 6-3 Wholesale)

6.6.3 Recycled Water System
As discussed above, the City does not currently operate a recycled water system within its water service area. The City delivers tertiary treated recycled water to DPWD via the DMC as part of the North Valley Program. Secondary treated effluent is either used to irrigate City-owned ranch lands or stored in on-site ponds. MID also does not operate a recycled water system. The City and MID do not have any future plans to develop recycled water systems within their respective water service boundaries.

6.6.4 Current and Potential Future Recycled Water Uses
As discussed above, the City currently uses recycled water (secondary treated effluent) for agricultural irrigation on City-owned ranch lands located outside of its water service area and delivers tertiary treated recycled water as part of the North Valley Program, which is also outside of its water service area.

Therefore, there is no existing or planned beneficial use of recycled water within the City’s water service area, as shown in Table 6-10 (DWR Table 6-4 Retail).

The City’s Joint 2020 UWMP did not project any recycled water use in 2025, and no recycled water was used within the City’s water service area in 2025. Therefore, Table 6-11 (DWR Table 6-5 Retail) has been intentionally left blank.

Treatment
Level
Drop down
list
Volume
(AF)
Treatment
Level
Drop down
list
Volume
(AF)
Treatment
Level
Drop down
list
Volume
(AF)
Treatment
Level
Drop down
list
Volume
(AF)
Treatment
Level
Drop down
list
Volume
(AF)
Name of
other
entity
0 0 0 0 0 0 0
Check the box if the Wholesale Supplier neither distributes nor provides supplemental treatment to recycled water.

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Table 6-10. Current and Projected Recycled Water Direct Beneficial Uses Within Service Area (DWR Table 6-4 Retail)
Table 6-11. 2020 Recycled Water Use Projection Compared to 2025 Actual (DWR Table 6-5 Retail) MID is not directly involved with the distribution of recycled water, and has no plans to do so. Therefore, Table 6-12 (DWR Table 6-4 Wholesale) and Table 6-13 (DWR Table 6-5 Wholesale) have been intentionally left blank.

Table 6-12. Current and Projected Recycled Water Direct Beneficial Uses Within Service Area (DWR Table 6-4 Wholesale)
Volume
Narrative page
number
(OPTIONAL)
0 Section 6.6.4
0 0 0 0 0 0 0
0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
Check box if recycled water is not used and is not planned for use within the service area of the supplier. The supplier will only complete the column on "Potential Recycled Water Use" and submit an accompanying narrative on the feasibility of that potential recycled water use.

Potential Recycled
Water Use
Name(s) of Facility/ies Producing (Treating) the Recycled Water Name of Supplier Operating the Recycled Water Distribution System Volume of Supplemental Water Added in 2025 (OPTIONAL) :

Source of 2025 Supplemental Water (OPTIONAL) :

Total
Use Type
Drop down list
Potable or NonPotable
(after treatment if
treated)
(OPTIONAL)
Drop down list
Additional
Information
(as needed)
2050
(AF)
2025
(AF)
2030
(AF)
2035
(AF)
2040
(AF)
2045
(AF)
Subtotal Potable
Subtotal Non-Potable
2020 Projection
for 2025 (AF)
2025 Actual
Use (AF)
0 0
Check the box if recycled water was not used in 2025 nor previously projected for use in 2020.

Proceed to the next table.

Total
Use Type
Drop Down list
Volume
Narrative page
number
(OPTIONAL)
0 Section 6.6.4
0 0 0 0 0 0 0
0 0 0 0 0 0 0
Total 0 0 0 0 0 0 0 0
Name of Receiving
Supplier or Direct
Use by Wholesale
Supplier
Potable or NonPotable
(after treatment if
treated)
(OPTIONAL)
Drop down list
Additional
Information
(as needed)
Name(s) of Facility/ies Producing (Treating) the Recycled Water (OPTIONAL) :

Name of Supplier Operating the Recycled Water Distribution System Volume of Supplemental Water Added in 2025 (OPTIONAL) :

Source of 2025 Supplemental Water (OPTIONAL) :

Check box if recycled water is not used and is not planned for use within the service area of the supplier. The supplier will only complete the column on "Potential Recycled Water Use" and submit an accompanying narrative on the feasibility of that potential recycled water use.

Potential Recycled
Water Use
2050
(AF)
2025
(AF)
Subtotal Potable
Subtotal Non-Potable
2030
(AF)
2035
(AF)
2040
(AF)
2045
(AF)
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Table 6-13. 2020 Recycled Water Use Projection Compared to 2025 Actual (DWR Table 6-5 Wholesale)

6.6.4.1 Potential Future Recycled Water Uses
Other potential future beneficial uses of recycled water in the City’s water service area include environmental uses and groundwater recharge. These potential beneficial uses have some implementation constraints, as discussed below.

6.6.4.1.1 Environmental Use
Potential future recycled water opportunities for environmental uses include stream flow augmentation, wildlife habitat restoration, wetland enhancement, and other related environmental purposes. One potential environmental use is augmentation of summer flow in the San Joaquin River with disinfected tertiary treated recycled water. This could enhance habitat in the San Joaquin River and the Delta during the summer months. Environmental uses of recycled water would require evaluation in future studies to assess the potential impacts to local groundwater supplies, agricultural lands, and other environmental habitats.

Through an agreement with DPWD, recycled water transported via the DMC is currently used to enhance a wetland area. This beneficial use could be expanded to develop additional wetlands that provide habitat for endangered species and other wildlife. Constructing/developing wetlands in the Modesto area would likely require conversion of agricultural land or modification of other land uses.

Recycled water quality is a significant consideration for environmental use since pharmaceuticals, trace elements, pesticides, and other constituents could potentially result in adverse impacts to aquatic and other wetland species. The quality of recycled water required for environmental use is dependent on the specific uses of the water (i.e., wetlands have different needs than stream flow augmentation projects).

Treatment requirements and water quality goals should be evaluated in the future as specific environmental projects are identified.

6.6.4.1.2 Groundwater Recharge
Using municipal recycled water as a recharge source for groundwater subbasins used for municipal water supply purposes is an approved practice in California. A groundwater recharge project could supplement and increase the groundwater basin operational yield.

Groundwater recharge using recycled water may be implemented through either surface spreading (e.g., recharge basins or percolation ponds) or direct injection. Direct injection projects require full advanced treatment, including technologies such as reverse osmosis (RO) and ultraviolet disinfection, to remove pathogens, organics, trace constituents, and other impurities prior to recharge. These advanced treatment processes are expensive to construct and operate. Management of RO concentrate (brine) would represent additional challenges, as discharge of brine is generally not allowed to any 2020 Projection
for 2025 (AF) 2025 Actual Use (AF)
0 0
Check the box if recycled water was not used or distributed by the supplier in 2025, nor projected for use or distribution in 2020.

Proceed to the next table.

Total
Name of Receiving Supplier or Direct
Use by Wholesale Supplier
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inland surface water and would require specialized disposal methods such as evaporation or other management approaches.

Groundwater recharge via surface spreading allows recycled water to percolate through the soil, receiving additional soil treatment, and then commingling with native groundwater. The potential effects on the existing groundwater quality constituents, such as salinity, nitrates, arsenic, trace elements, iron, and manganese, would require evaluation. Regulatory requirements for groundwater recharge depend on site-specific factors such as recharge method, recycled water quality, aquifer and soil characteristics, and proximity to production wells.

At this time, groundwater recharge using recycled water is not included for the City in the planning horizon of this UWMP. As discussed in Section 6.9.2, the City continues to evaluate the potential for managed aquifer recharge using purchased surface water or flood flows; however, recharge using recycled water is not currently being considered.

6.6.5 Actions to Expand Future Recycled Water Use
The City plans to continue providing recycled water to DPWD for agricultural irrigation as part of the North Valley Program and to continue using recycled water for land application on City-owned ranch lands. Any future increases in recycled water availability resulting from increasing water demands and wastewater flows within the City’s service area are anticipated to be used for these same purposes. The City does not currently have plans to expand recycled water use beyond these existing uses. Therefore, these recycled water uses are not accounted for in Table 6-14 (DWR Table 6-6 Retail).

Table 6-14. Methods to Expand Future Recycled Water Use (DWR Table 6-6 Retail)

6.7 DESALINATED WATER
Desalination is the process of removing dissolved minerals from brackish water or saltwater to produce freshwater that can be used for municipal needs such as drinking water and industrial uses. It is one of several elements that may be included in a community’s water supply portfolio.

The City and MID’s service area is not located in a coastal area, so seawater desalination is not applicable and is not considered a technically or economically feasible opportunity to explore. Additionally, while saline water is present deep underground below the freshwater aquifers in the groundwater basin, it would not be cost effective to use due to the depth to saline water, significant cost of treatment, and other issues such as brine disposal.

Section 6.6.5
Name of Action Description
Expected Increase in
Recycled Water Use
(AF)
0 0
Total (AF)
Check the box if the Supplier does not plan to expand recycled water use in the future. Supplier will not complete the table below but will provide narrative explanation.

Provide page location of narrative in the UWMP
Unit Conversion to AF
Planned
Implementation Year
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The Grayson service area, however, includes wells that produce groundwater with TDS concentrations ranging from 1,100 to 1,300 mg/L, which exceeds California secondary drinking water standards.

Secondary drinking water standards address the taste, odor, and appearance of drinking water, compared to primary drinking water standards which address health concerns.21 Although this groundwater is not a traditional seawater source, it may be considered brackish based on its elevated salinity. The City has considered treatment of this source; however, the associated costs are high, and the City is therefore exploring other alternatives, such as additional sources of supply or consolidation.

Therefore, the City and MID did not include or consider desalinated water in planning for its future supply sources.

6.8 EXCHANGES OR TRANSFERS
This section describes the City and MID’s opportunities for exchanges or transfers of water on a short-term or long-term basis. Water exchanges are typically water delivered by one water user to another water user, with the receiving user providing water in return at a specified time or when the conditions of the parties’ agreements are met. The CWC defines water transfers as a temporary or long-term change in the point of diversion, place of use, or purpose of use due to transfer, sale, lease, or exchange of water or water rights. Temporary water transfers have a duration of one year or less, and long-term water transfers have a duration of more than one year.

During supply shortage years, MID surface water supplies may be reduced, and subsequently, MID’s treated surface water supply deliveries to the City would be reduced in equal proportion to deliveries for agricultural customers.

The City and MID may execute exchange agreements to allow the City to deliver groundwater to MID's irrigation canal system in exchange for an equal amount of raw surface water to be treated at the MRWTP during dry years. Although this exchange option has not been utilized to date, it remains available as a potential short-term supply management tool for both agencies. In general, MID has not sought exchange or transfer opportunities.

As the City and MID already have the ARTDA in place for purchasing surface water, other long-term transfer or exchange opportunities are not expected.

6.9 FUTURE WATER PROJECTS
Because the City is projected to have sufficient supplies to meet future water demands as documented in the City’s 2017 Water Master Plan and this Joint UWMP, the need for and timing of potential water supply projects have not been determined. Therefore, these potential future water supply projects are not currently included in the City and MID’s future water supply portfolio, and Table 6-15 (DWR Table 6-7 Retail) and Table 6-16 (Table 6-7 Wholesale) have been intentionally left blank. 21 State Water Resources Control Board. Contaminants in Drinking Water. Accessed at https://www.waterboards.ca.gov/drinking_water/certlic/drinkingwater/Chemicalcontaminants.html #20..
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Table 6-15. Expected Future Water Supply Projects or Programs (DWR Table 6-7 Retail) Table 6-16. Expected Future Water Supply Projects or Programs (DWR Table 6-7 Wholesale) The following sections briefly discuss potential future water supply projects that the City and/or MID may consider to increase available supply, including both purchased surface water from MID and local groundwater.

6.9.1 Future Surface Water Supply Options
Treated surface water purchased from MID is a key component of the City’s existing water supply portfolio. A Phase Three expansion of MRWTP may be possible in the future to increase treatment capacity if the City’s long-term water use trends and growth warrant additional capacity. However, based on the City’s current water conservation efforts and urban water use objectives, the City does not anticipate the need for this additional capacity within the planning horizon of this Joint UWMP.

MID plans to rebuild the existing monomedia filters and replace aged membrane filters at the MRWTP within the next three to five years. These improvements will improve reliability of the treatment system but will not directly increase available supply and are therefore not included in Table 6-15 or Table 6-16.

Drop Down List
(yes/no)
If Yes,
Supplier
Name
Planned for
Use in Year
Type
Drop Down List
Check the box if some or all of the supplier's future water supply projects or programs are not compatible with this table and are described in a narrative format.

Check the box if there are no expected future water supply projects or programs that provide a quantifiable increase to the agency's water supply.

Proceed to the next table.

Planned
Implementation
Year
Joint Project with other
suppliers?
Expected
Increase in
Water
Supply to
Supplier
(This may be
a range) (AF)
Provide page location of narrative in the UWMP
Name of Future
Projects or
Programs
Additional
Description
(as needed)
Potable or
Non-Potable
(after
treatment if
treated)
(OPTIONAL)
Drop Down list
Drop Down List
(yes/no)
If Yes,
Supplier Name
Provide page location of narrative in the UWMP
Check the box if some or all of the supplier's future water supply projects or programs are not compatible with this table and are described in a narrative format.

Check the box if there are no expected future water supply projects or programs that provide a quantifiable increase to the agency's water supply.

Proceed to the next table.

Name of Future
Projects or
Programs
Additional
Description
(as needed)
Potable or
Non-Potable
(after
treatment if
treated)
(OPTIONAL)
Drop down list
Planned
Implementation
Year
Planned for
Use in Year
Type
Drop Down list
Expected
Increase in
Water
Supply to
Supplier
(This may be
a range) (AF)
Joint Project with other
suppliers?
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6.9.2 Future Groundwater Supply Considerations
Groundwater is a key component of the City’s existing water supply portfolio. The following sections describe potential future groundwater supply options, including:
• Groundwater Well Capital Improvements
• Potential Aquifer Storage and Recovery (ASR) Program
• Potential Managed Aquifer Recharge (MAR) Program

6.9.2.1 Groundwater Well Capital Improvements
As part of the City’s normal water system maintenance and operations, the City will construct and rehabilitate groundwater wells and wellhead treatment systems as needed to maintain, at a minimum, existing groundwater production capacity and to ensure reliable water supply to meet future demands.

The City employs a conjunctive use approach, balancing groundwater and surface water supplies to optimize overall supply reliability. Accordingly, as water demands increase due to future growth, additional groundwater well improvements and new wells may be required to maintain the City’s target balance between groundwater and surface water production capacity. The City’s Capital Improvement Program (CIP) includes rehabilitation and replacement of groundwater wells, wellhead treatment systems, and related infrastructure to support this approach.22 The City is currently in the process of planning and designing wellhead treatment for multiple wells that are currently inactive due to elevated DBCP and 1,2,3-TCP in both the contiguous service area and Del Rio outlying service area. These projects will help restore lost well production capacity and improve local groundwater quality by reducing contaminant loading and mitigating the extent of the contamination plume within the aquifer. Additional wellhead treatment projects that have not yet been identified may be required in the future, as water quality conditions change over time, or as drinking water regulations become more stringent.

6.9.2.2 Potential Aquifer Storage and Recovery Program
The City’s 2017 Water Master Plan included a conceptual-level evaluation for ASR within the groundwater basin underlying the City’s contiguous water service area. The focus of this evaluation was to review existing data on the City’s wells and groundwater basin hydrogeologic and geochemical characteristics and determine the conceptual feasibility of injecting, storing, and recovering treated surface water within the groundwater aquifer beneath the City.

ASR is a form of managed aquifer recharge that involves the seasonal banking of water in an aquifer during times when excess water is available (typically winter and spring) and subsequent recovery of the water from the aquifer when needed (typically fall and summer, and/or during drought periods). ASR utilizes dual purpose injection/recovery wells for the injection of treated, potable water for storage, and the subsequent recovery of this previously stored water by pumping. The advantage of ASR technology is that it allows recharge to be applied in those geographic areas or aquifer zones with the most need, or where 22 City of Modesto. Capital Improvement Program. Accessed at https://www.modestogov.com/2591/CapitalImprovement-Program on April 5, 2026. #20..
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available groundwater storage space is the greatest. In addition, ASR sites require minimal land use area, so they can be more easily located than spreading basins or other recharge facilities.

Conceptually, treated surface water purchased on a wholesale basis from MID could be used when seasonally available surplus supply is available to develop an ASR program for the City. The ASR program, if determined to be feasible, could provide the City with enhanced groundwater operational yield and improved groundwater quality. A pilot study would be needed to confirm that the water quality of the groundwater pumped for distribution meets standards for potable water use.

The overall conclusion based on what has been analyzed to date is that an ASR Program could be viable in the groundwater basin underlying the City. It is recommended that the City move forward with additional necessary ASR-related studies to empirically verify the conclusions of the initial study and to develop site specific data regarding the effectiveness, impacts, and economics of ASR. These test program data would then serve as the basis for evaluating, planning, and permitting a full-scale ASR Program within the City.

6.9.2.3 Potential Managed Aquifer Recharge Program
The City also completed a Wellfield Remedial Investigation Feasibility Study (RIFS) in June 2021, which was performed under a grant agreement with the State Water Board. The RIFS evaluated various alternatives to mitigate impacts from arsenic, nitrate, and uranium in the City’s production wells throughout the City’s service area. These alternatives included adjusting wellfield pumping strategies, managed aquifer recharge, aquifer storage and recovery, and physical wellfield modifications.

The recommended alternative included a hybrid approach using managed aquifer recharge and adjusting wellfield pumping strategies by decreasing or eliminating pumping of certain wells with poor water quality. Managed aquifer recharge would aim to improve groundwater quality, particularly in the shallow and intermediate aquifer zones, through strategic recharge of surface water purchased from local irrigation districts, including flood flows, into new and existing recharge basins. The City is continuing to assess the potential use of managed aquifer recharge.

6.10 SUMMARY OF EXISTING AND PLANNED SOURCES OF WATER

6.10.1 Existing and Planned Sources of Water for the City The City’s existing and planned sources of water can be summarized as such:
• The City has 76 active, potable groundwater wells in both the contiguous and outlying service areas, with a total well capacity of approximately 86 MGD. — To maintain adequate groundwater supply capacity to meet future demands, the City plans to rehabilitate, add wellhead treatment, and construct additional groundwater wells as needed.
— The City also uses non-potable irrigation wells to serve some City parks. • The City purchases treated surface water from MID, with the Phase 2 MRWTP capable of providing a total annual average design capacity of 60 MGD, supporting a maximum annual supply of up to 67,200 AFY.
• The City maintains a series of stormwater detention basins and other stormwater facilities that contribute to groundwater recharge.
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• The City currently uses secondary treated recycled water for agricultural irrigation on City-owned ranch lands outside of its water service area and delivers tertiary treated recycled water for agricultural irrigation through the North Valley Program, which is also located outside of the service area. As a result, the City has no existing or planned use of recycled water within its water service area.

The City’s actual potable and non-potable water supplies used in 2025 are summarized in Table 6-17 (DWR Table 6-8 Retail). The volume shown is based on the actual 2025 production from each potable and non-potable source.

Table 6-17. Water Supplies – Actual (DWR Table 6-8 Retail) The City’s projected future potable and non-potable water supplies are summarized in Table 6-18 (DWR Table 6-9 Retail). The reasonably available volume of purchased surface water and groundwater is based on the City’s projected demands shown in Chapter 4. These projections assume that the City plans to increase the use of available treated surface water supplies purchased from MID to meet 70 percent of future water demands and supplement with groundwater to meet the remaining demands. It should be noted that the actual proportion of surface water and groundwater use may differ due to various operational factors.

Table 6-18 indicates that the City has adequate surface water supply and groundwater supply to meet projected demands during a normal hydrologic year. While projected surface water demands remain below the City’s maximum surface water entitlement, surface water supplies may be reduced during dry years. Under these conditions, the City would need to rely on its available groundwater supplies to meet the remaining demand. The City’s actual surface water supply quantity available will be based on the City’s increase in demand and will need to conform to requirements of the ARTDA. Overall, the City’s projected supplies reflect its on-going conjunctive use strategy, which balances surface water and groundwater supplies to meet demands under normal conditions, as well as during dry years and extended drought periods, as described further in Chapter 7.

Water Supply
Drop down list
May use each category multiple
times. These are the only water
supply categories that will be
recognized by the WUEdata online
submittal tool
Potable or Non-Potable
(after treatment if treated)
(OPTIONAL)
Drop Down list
Actual Volume
(AF)
Total
Entitlement
(OPTIONAL)
See 'DWR Notes'
below (AF)
Purchased or Imported Water Purchased surface water
from MID Potable 29,125 67,200
Groundwater (not desalinated) Potable 20,613 -
Groundwater (not desalinated) Raw water irrigation wells Non-Potable 1,865 - 49,738 -
1,865 -
51,603 -
2025
NOTES: Volumes are based on actual surface water and groundwater production in 2025, consistent with DWR Table 4-1 Wholesale and DWR Table 6-1 Retail, respectively. The maximum surface water entitlement of 67,200 AFY is based on the ARTDA. The actual surface water supply quantity available will be based on the City’s increase in demand and will need to conform to requirements of the ARTDA.

DWR NOTES:

Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3. This table identifies the unit of measure selected in Submittal Table 2-3.

Total Entitlement: e.g. Water Right, Groundwater Allocation, Contracted Amount.

Total
Subtotal Potable
Subtotal Non-Potable
Additional Description
(as needed)
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6.10.2 Existing and Planned Sources of Water for MID
MID’s annual treated surface water supplies delivered to the City in 2025 are summarized in Table 6-19 (DWR Table 6-8 Wholesale).

Table 6-19. Water Supplies – Actual (DWR Table 6-8 Wholesale) Table 6-20 (DWR Table 6-9 Wholesale) summarizes MID’s projected annual treated surface water deliveries to the City through 2050. Values presented are consistent with Table 4-6 (DWR Table 4-2 Wholesale) and Table 6-18 (DWR Table 6-9 Retail). As previously discussed, the MRWTP Phase Two Expansion project can provide up to an additional 30 MGD of treatment capacity, for a total annual supply of up to 67,200 AFY.

Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3. This table identifies the unit of measure selected in Submittal Table 2-3.

Total Entitlement: e.g. Water Right, Groundwater Allocation, Contracted Amount.

Total
Subtotal Potable
Subtotal Non-Potable
Additional Description
(as needed)
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6.11 CLIMATE CHANGE IMPACTS TO SUPPLY
An extensive evaluation on the impacts of climate change is included in the East Stanislaus Integrated Regional Water Management Plan (ESIRWMP) Update (February 2018). The City was included in the East Stanislaus Regional Water Management Partnership (ESRWMP), the official Regional Water Management Group for the region, along with the cities of Hughson, Ceres, Turlock, Waterford, and Stanislaus County.

The ESIRWMP planning region lies within the San Joaquin River Hydrologic Region and contains the Stanislaus, Tuolumne, Merced and San Joaquin Rivers, and Dry Creek. The Stanislaus, Tuolumne and Merced Rivers are all tributaries to the San Joaquin River, with the Tuolumne River having the largest watershed in the San Joaquin River system. Key findings from the climate change evaluation in the ESIRWMP Update are summarized below.

There is mounting scientific evidence that global climate conditions are changing and will continue to change as a result of the continued build‑up of GHGs in the Earth’s atmosphere and other issues. Changes in climate can affect municipal water supplies through modifications in the timing, amount, and form of precipitation, as well as water demands and the quality of surface runoff. These changes can affect all elements of water supply systems, from watersheds to reservoirs, conveyance systems, and treatment plants. Planning for and adapting to the anticipated changes in climate will be essential to ensure water supply reliability for all users and to protect sensitive infrastructure against potentially more frequent and extreme precipitation and wildfire events.

Climate change is adding new uncertainties to already existing challenges in water resources planning within the ESIRWMP planning region because the water supply portfolio in the region is not widely diversified. Water supplies are derived from multiple subbasins of the San Joaquin Valley Groundwater Basin and primarily from the Tuolumne River. Climate change will impact groundwater and surface water differently, but the region’s vulnerabilities are the same regardless of the source:
• Reduced surface water availability
• Reduced water supply reliability as a result of reduced groundwater recharge and runoff • Potential increase in groundwater overdraft
• Declining water quality
• Loss of riparian habitat, wetlands and other sensitive natural communities • Reduced hydroelectric generation capacity
Considering the amount of uncertainty associated with climate change projections, a prudent approach to addressing climate change incorporates a combination of adaptation and mitigation strategies. Climate adaptation includes strategies (policies, programs or other actions) that bolster community resilience in the face of unavoidable climate impacts, where mitigation strategies include best management practices (BMPs) or other measures that are taken to reduce GHG emissions.

For the City, the implementation of its overall water conservation program, particularly the recent completion of the residential metering program, will help to reduce water demands, and also conserve energy as a result of decreased water treatment, conveyance and pumping requirements. The City’s compliance with SB X7-7 per capita water use targets and urban water use objectives will also ensure continued water conservation and energy conservation in the future. #20..
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As described in MID’s 2025 Agricultural Water Management Plan, MID is committed to (1) monitoring key indicators of climate change that affect the hydrology of the Tuolumne River watershed and the growing conditions in MID’s irrigation service area, and (2) adapting its water management practices to respond to changes as they become evident. In addition to adaptive management, implementation of the water conservation initiatives currently underway at MID will help MID and its agricultural water users prepare for the potential impacts of climate change by improving operational control. Improving operational control will enable MID to exercise adaptive management measures should they become necessary.

6.12 ENERGY INTENSITY
In accordance with CWC Section 10631.2(a), the energy intensity to provide water service to the City’s customers over a one-year period is presented in this section to the extent that the information is available. The amount of energy to divert, pump, treat, and distribute the City and MID’s water supply within the systems they own and operate are included.

Water energy intensity is the total amount of energy, calculated on a whole-system basis, used to deliver water to the City’s customers for use. Energy intensity is the total amount of energy in kilowatt-hours (kWh) expended per million gallons (MG) to take water from its source to its point of delivery. For MID, this means the energy required to treat surface water and deliver potable water to the City. For the City, this means pumping and treating groundwater and delivering potable water to its customers. Understanding the whole-system energy intensity allows the City and MID to develop the following water supply management and system operation strategies:
• Identify energy saving opportunities, as energy consumption is often a large portion of the cost of delivering water
• Calculate energy savings and GHG emission reductions associated with water conservation programs
• Identify potential opportunities to obtain energy efficiency funding for water conservation programs
• Inform climate change mitigation strategies
• Benchmark energy use at each water extraction, treatment, and delivery step and comparing energy use among similar agencies
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6.12.1 Water System Energy Intensity

6.12.1.1 City Energy Use
In Table 6-21 (DWR Table O-1B), the energy intensity of the City’s water service is calculated as an annual utility total for 2025. Annual energy use quantities were obtained from the City’s monthly energy billing data for its groundwater well sites throughout its contiguous service area and outlying service area. Energy usage reported excludes data for booster pump stations used at the City's storage reservoirs, which were not readily available.

The total energy use for these facilities in 2025 was approximately 14,883,001 kWh. Based on the City’s total groundwater production in 2025 of 20,613 AF (which excludes purchased surface water from MID), the total energy intensity for the City’s water service is approximately 2,216 kWh/MG.

6.12.1.2 MID Energy Use
In Table 6-22 (DWR Table O-1B), the energy intensity of MID’s water service is calculated as an annual utility total for 2025. Annual energy use quantities were obtained from MID’s monthly energy billing data for the MRWTP and the Terminal Reservoir Pump Station.

The total energy use for these facilities in 2025 was approximately 8,053,000 kWh. Based on MID’s total treated surface water production in 2025 of 29,125 AF23, the total energy intensity for MID’s water service is approximately 849 kWh/MG.

6.12.2 Wastewater System Energy Intensity
As discussed in Section 6.6, the City treats wastewater at the Sutter Avenue Primary Treatment Plant, which is subsequently conveyed to the Jennings Road Treatment Plant for further treatment and discharge. The energy intensity associated with the City’s two wastewater treatment plants (WWTPs) for 2025 is provided in Table 6-23 (DWR Table O-2). Energy usage reported includes data for wastewater lift stations used to convey wastewater to the City's WWTPs and pumping used to discharge treated effluent.

The total energy use for these two WWTPs in 2025 was approximately 28,823,161 kWh. Based on the City’s estimated wastewater volume treated at the Jennings Road Treatment Plant in 2025 of 26,323 AF, the total energy intensity for the City’s WWTPs is approximately 3,360 kWh/MG.

Since the City does not distribute recycled water within its water service area, energy intensity for recycled water is not included. Similarly, wastewater energy intensity is not provided for MID, as MID does not collect or treat wastewater.
23 The City reported 29,125 AF in its 2021–2025 Production spreadsheet. MID’s reported plant production total for calendar year 2025 is 29,171 AF, which is 46 AF higher (a 0.16 percent difference). Although minor, this discrepancy should be noted. For consistency, the value of 29,125 AF was used throughout this plan. #20..
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CHAPTER 7
Water Service Reliability and Drought Risk Assessment
This chapter describes the City and MID’s water service reliability under various hydrologic conditions through 2050. In assessing the City and MID’s water service reliability, a comparison of projected water supplies and demand under normal year, single dry year, and five-consecutive-year drought conditions are provided. This chapter also includes the City and MID’s Drought Risk Assessment (DRA) which evaluates the risk of a severe drought occurring for the next five consecutive years.

Findings show that the City’s water supplies are sufficient to meet the existing and projected water demands during normal and drought conditions. While MID’s surface water supplies may be reduced during drought conditions, the City maintains adequate groundwater supply to conjunctively use with available surface water supply to meet demands.

The City and MID’s water management tools to address the reliability of water supplies and promote regional supply reliability are also discussed in this chapter. Responses to water shortage conditions are addressed in Chapter 8 and Appendix G.

7.1 CONSTRAINTS ON WATER SOURCES
As described in Chapter 6, the City relies on two primary sources of water supplies: wholesale treated Tuolumne River surface water deliveries from MID and local groundwater pumping. This section provides a general description of the constraints on the City and MID’s urban water supplies for use in the following water service reliability assessment and DRA.

7.1.1 MID Surface Water
In general, MID’s surface water supplies are most vulnerable to climatic variability. Below average snowpack and/or prolonged periods of dry weather contribute to reduced surface water availability. The quality of water from the Tuolumne River is generally not of concern as MID treats surface water at its MRWTP to a level consistently exceeding drinking water standards. Therefore, MID’s urban water service reliability is mostly dependent on water quantity rather than water quality.

Legal issues, including place of use and water rights issues, are not anticipated to limit supply reliability for MID’s urban water supplies in future years. Environmental factors can potentially limit the reliability of surface water supplies, such as during a drought when dry year supply cutbacks are necessary to maintain the health of aquatic species and the environment in general.

7.1.1.1 Federal Energy Regulatory Commission Fish Flow Requirement A potential future constraint on MID’s available surface water supplies is the ongoing Federal Energy Regulatory Commission (FERC) relicensing of Don Pedro Reservoir. Don Pedro Reservoir is jointly owned and operated by MID and Turlock Irrigation District (TID) and is subject to FERC jurisdiction due to the operation of a 203‑megawatt (MW) hydroelectric powerhouse.

FERC has authority to license and relicense non‑federal hydropower projects on navigable rivers for terms of 30 to 50 years. The original 50‑year FERC license for Don Pedro Reservoir expired in April 2016, and MID and TID have since operated the project under annual license extensions while pursuing a new long‑term license. As part of the relicensing process, FERC may modify operational requirements, including minimum instream flow release requirements, which vary by water year type. #20..
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FERC is mandated to give equal consideration to beneficial public uses (including energy conservation, irrigation, flood control, water supply, recreational opportunities, and other aspects of environmental quality) and adequate protection, mitigation and enhancement of fish and wildlife. The existing Don Pedro Reservoir license includes minimum instream flow requirements intended to support aquatic and riparian habitat conditions in the Tuolumne River.

The outcome of the ongoing relicensing process could result in changes to minimum instream flow requirements or other operational conditions, which may affect the timing and quantity of surface water available to MID, and consequently the amount of Tuolumne River water available for delivery to the City, depending on hydrologic conditions and final license terms.

7.1.1.2 Tuolumne River Emergency Curtailment Orders
MID’s surface water availability may be impacted during dry years by curtailment orders from the State Water Board. In the recent 2022 dry year, the State Water Board issued emergency curtailment orders affecting Tuolumne River diversions, including certain post-1914 appropriative water rights held by MID, a senior water rights holder on the river. These curtailment orders temporarily restricted MID from diverting Tuolumne River flows under its post-1914 appropriative rights for direct use or for storage into Don Pedro Reservoir.

During these conditions, MID was still able to use surface water previously stored in Don Pedro Reservoir. In response to the drought, MID’s water allocations in the 2022 irrigation season were reduced to 30 inches, or approximately 71 percent of its full allocation.

7.1.1.3 Bay-Delta Water Quality Control Plan
The State Water Board’s Bay-Delta Water Quality Control Plan (Bay-Delta Plan) presents emerging regulatory conditions that may impact MID’s surface water supply availability from the Tuolumne River.

The State Water Board and the Regional Water Quality Control Boards are responsible for adopting Water Quality Control Plans that include measures to protect water quality in the state’s streams, rivers, and lakes. The Bay-Delta Plan identifies beneficial water uses to be protected in the Bay Delta, including:
municipal and industrial, agricultural and fish and wildlife, water quality and flow objectives to reasonably protect the beneficial uses. The Bay-Delta Plan includes an implementation program to meet its objectives. Under the program, the State Water Board may take actions, including imposing minimum flow requirements, or habitat restoration requirements for diverters.

As the Tuolumne River is a tributary to the San Joaquin River, the Bay-Delta Plan sets instream flow requirements and water quality objectives for the Tuolumne River. On December 12, 2018, the State Water Board adopted amendments to the Bay-Delta Plan which established Lower San Joaquin River (LSJR) flow objectives and revised southern Delta salinity objectives. These amendments to the Bay-Delta Plan applied to three tributaries to the San Joaquin River: the Tuolumne, Merced, and Stanislaus Rivers.

The flow objectives for the Tuolumne River would require MID and TID to release 40 percent of unimpaired flows into the Tuolumne River from February 1 to June 30 for salmon and salinity control in the Delta. Per TID’s 2020 AWMP, TID, MID, and SFPUC release approximately 17 percent of the unimpaired flows to the Tuolumne River, while the remainder is diverted for beneficial use. The State Water Board released revised draft updates to the Bay Delta Plan, including LSJR flow and southern Delta salinity provisions, in December 2025 along with an updated environmental analysis. Public review and hearings are being conducted in early 2026.
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The Tuolumne River Partners – MID, TID, and SFPUC – proposed a comprehensive alternative to the unimpaired flow requirements in the Bay-Delta Plan. The alternative is presented in the proposed Tuolumne River Voluntary Agreement, referred to as the Agreements to Support Healthy Rivers & Landscapes. This agreement provides a foundation for comprehensively managing the Tuolumne River and for continued management of Chinook salmon and rainbow trout within the lower Tuolumne River.

While the proposed Voluntary Agreement will still require MID to release more water to the Tuolumne River for ecosystem benefits, the agreement will offer MID more opportunity to mitigate water supply impacts on its customers while still comprehensively managing the Tuolumne River to the State Water Board’s standards. The proposed Tuolumne River Voluntary Agreement is currently being evaluated by the State Water Board. While significant work remains, this proposed Voluntary Agreement represents an important step forward in bringing together diverse California water interests.

7.1.2 Groundwater
In contrast to surface water supply reliability, the City’s local groundwater reliability is more affected by water quality concerns and the high costs associated with treatment, rather than by availability.

Historically, contamination from arsenic, uranium, PCE, TCE, DBCP, TCP, and nitrate has resulted in the need for wellhead treatment to keep wells from being taken out of service. To address these challenges, the City has developed strategies to keep existing wells online and return selected inactive wells back online through a combination of wellhead treatment, blending, and on-going monitoring. As a result, groundwater quality is not expected to threaten the City’s ability to use groundwater supplies to supplement its surface water supply and meet current and future water demands.

While drought conditions can significantly reduce surface water availability, the effects on groundwater are less pronounced. Historically, the City has maintained reliable access to groundwater under all hydrologic conditions. As described in Chapter 6, the City has established an estimated operational yield for its groundwater supplies and manages pumping to remain within this operational yield. Under these conditions, the City’s groundwater supply is not expected to be reduced during dry years.

Legal issues, including place of use and water rights issues, are not expected to limit the reliability of the City’s groundwater supplies in future years.

7.2 WATER SERVICE RELIABILITY ASSESSMENT
This section evaluates the City and MID’s water service reliability for a normal year, single dry year, and five-consecutive-year drought. The City and MID’s water service reliability are presented in five-year increments through 2050 based on the previous analysis of water use and supply (discussed in Chapter 4 and Chapter 6, respectively). For the purposes of this water service reliability assessment, available water supply during normal year, single dry year, and five-consecutive-year drought are compared with unconstrained normal year customer demands.

During any water shortage events identified, the City may implement actions from its WSCP, which is discussed in Chapter 8 and provided in Appendix G of this plan. MID may also implement its water shortage allocation policies and drought plan which is included in MID’s Draft 2025 AWMP. #20..
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7.2.1 Year Type Characterization
This section describes the historical basis for projecting available supplies under various hydrologic conditions for use in the water service reliability assessment. Water supplies can vary year to year depending on hydrologic conditions. Historical data, where available, were used to develop a projected yield for each water supply source under three conditions: (1) normal year, (2) single dry year, and (3) five-consecutive-year drought. In accordance with the DWR Guidebook, each condition is defined as follows:
• Normal Year: The year or averaged range of years in the historical sequence most closely representing average water supply.
• Single Dry Year: The year with the lowest water supply in the historical sequence. • Five-Consecutive-Year Drought: The driest five-year historical sequence.

The following sections describe the historical calendar years selected to represent each of the above conditions for the City and MID’s water supplies, including surface water and groundwater.

7.2.1.1 MID Surface Water
MID’s historical water allocations to its customers from 1989 through 2025 were reviewed to project MID’s surface water supply available to the City under the three hydrologic conditions. This approach is appropriate because the ARTDA specifies that the City’s water allocations are in alignment with MID’s agricultural customers, meaning that the City’s water allotment will be reduced in an equivalent manner to all other MID customers. As discussed in Chapter 6, the ARTDA includes a formula to reduce deliveries in drier than average years based on the number of inches allocated to MID’s agricultural customers.

Although MID began establishing annual water allocations for its agricultural customers in 1989, the City did not begin receiving water from MID until 1995.

MID determines its annual water allocation prior to the start of the irrigation season, which is a single, district-wide allocation that is applied uniformly to both agricultural and urban users. A full allocation for MID’s agricultural customers is defined as 42 inches of water per acre per year. In some dry or below normal years, MID is still able to maintain a 42-inch allocation when those years follow above-normal or wet water years.

Per MID’s Draft 2025 AWMP, MID considers various factors in determining its annual water allocation, including:
• Don Pedro Reservoir storage
• Modesto Reservoir storage
• Projected inflows from upstream reservoirs
• Projected inflows from precipitation
• Estimate of groundwater pumping based on San Joaquin River water year index • Minimum required flows in the Tuolumne River downstream of La Grange Diversion Dam • Irrigation system conveyance and evaporation losses
• Projected domestic water demands
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• Estimated irrigation deliveries
• Forecasted carryover water supplies
• Minimum end of season reservoir storage goal
Figure 7-1 shows MID’s historical water allocations from 1989 through 2025, as well as a year type characterization of hydrologic conditions. Table 7-1 summarizes more recent MID water allocations from 2010 through 2025, including the percent of full allocation.

Consistent with MID’s Draft 2025 AMWP, a normal year is assumed to yield a full allocation of 42-inches.

As shown on Figure 7-1, MID delivered full allocations to its customers in 22 of 37 years between 1989 through 2025, representing approximately 59 percent of years. Under normal and wet year conditions, it is anticipated that the City would receive its full water allotment from MID.

The single dry year was assumed to be represented by the Year 2015, which was MID’s lowest historical allocation. MID’s allocation in 2015 was 16 inches, equivalent to 38 percent of a full allotment.

The five-consecutive-year drought is represented by the Years 2012 through 2016, which was the most recent five-consecutive-year drought and includes the lowest historical allocation in 2015. As shown in Table 7-1, MID’s allocation in 2012 through 2016 varied from 38 percent of the full allocation (in 2015) to up to 86 percent of the full allocation (in 2012, 2013, and 2016).

Figure 7-1. Year Type Characterization Based on Historical MID Water Allocations #20..
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Table 7-1. Recent MID Water Allocations(a)
Year
Base Water Allocation to MID Customers,
inches/acre Percent of Full Allocation
2010 42 100
2011 42 100
2012 36 86
2013 36 86
2014 24 57
2015 16 38
2016 36 86
2017 42 100
2018 42 100
2019 42 100
2020 42 100
2021 36 86
2022 30 71
2023 42 100
2024 42 100
2025 42 100
(a) Source: Modesto Irrigation District's 2025 Draft Agricultural Water Management Plan.

Table 7-2 (DWR Table 7-1 Wholesale) estimates the City’s maximum available treated surface water supply from MID during the three hydrologic conditions described above. The table specifies the maximum volume available and percentage of average supply available if the hydrology from that type of year were to repeat. It should be noted that the City was not purchasing water supplies from MID throughout all of the base average years shown (deliveries from MID to the City began in 1995 with the completion of the MRWTP); therefore, the quantity shown is based on what the available supply would have been during the given hydrologic condition.

The maximum volume available in an average year is 67,200 AF, which represents the maximum annual quantity of treated surface water the City may receive from the expanded MRWTP under the ARTDA. In dry years, the maximum volume available is calculated by applying MID’s actual reduction in water allotment for the applicable base year to this maximum volume of 67,200 AF. The values reported in Table 7-2 are based on the total capacity available with the completion of the MRWTP Phase Two Expansion; the actual supply quantity available will be based on the City’s increase in demand and will need to conform to requirements of the ARTDA.

In dry years with reduced allocations, the City may purchase additional water from MID (at a higher rate) or exchange groundwater for agricultural use for treated surface water, if available. However, to be conservative in this analysis, supplemental surface water purchases or exchanges are assumed not to be available and are not included in Table 7-2 (DWR Table 7-1 Wholesale). #20..
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Table 7-2. Basis of Water Year Data (Reliability Assessment) (DWR Table 7-1 Wholesale)

7.2.1.2 Groundwater
Historically, the City has maintained reliable access to groundwater during all hydrologic conditions. As described in Chapter 6, the City pumps groundwater from the Modesto Subbasin to serve users north of the Tuolumne River and from the Turlock Subbasin to serve users south of the Tuolumne River. The Grayson outlying service area is supplied by local groundwater pumped from the underlying Delta-Mendota Subbasin.

The Modesto, Turlock, and Delta-Mendota subbasins are not adjudicated, meaning that there is no court-appointed “watermaster” to resolve groundwater pumping issues. The City’s groundwater pumping is regulated under SGMA and the applicable GSPs for each subbasin. The City maintains its groundwater pumping within its estimated operational yield, as described in Chapter 6. Under these conditions, the City’s groundwater supply is not expected to be reduced during single dry years or five-consecutive-year droughts. % of Average Supply
Average Year 1989-2025 100%
Single-Dry Year 2015 38%
Consecutive Dry Years 1st Year 2012 86%
Consecutive Dry Years 2nd Year 2013 86%
Consecutive Dry Years 3rd Year 2014 57%
Consecutive Dry Years 4th Year 2015 38%
Consecutive Dry Years 5th Year 2016 86%
Available Supplies if
Year Type Repeats
Check the box if quantification of available supplies is not compatible with this table and is provided
elsewhere in the UWMP.

Location: [insert location from UWMP]
Volume Available (AF)
NOTES: Volumes available are rounded to the nearest 10 AF. The volume available for the average year is based on the maximum annual volume of treated surface water that the City may receive from the expanded MRWTP per the ARTDA (67,200 AF). The volume available in dry years is based on the maximum volume of 67,200 AF multiplied by MID's actual reduction in water allotment to its customers during the respective base year. The actual supply quantity available in a given year will be based on the City’s increase in demand and will need to conform to requirements of the ARTDA.

DWR NOTES: Supplier may use multiple versions of Submittal Table 7-1 W if different water sources have different base years and the supplier chooses to report the base years for each water source separately. If a Supplier uses multiple versions of Submittal Table 7-1 W, in the "Note" section of each submittal table, state that multiple versions of Submittal Table 7-1 W are being used and identify the particular water source that is being reported in each submittal table.

Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3. This table reports the unit of measure selected in Submittal Table 2-3. 38,310
Quantification of available supplies is provided in this table as either volume only, percent only, or both.
57,800
25,540
57,800
67,200
25,540
57,800
Year Type
Base Year
If not using a
calendar year, type
in the last year of
the fiscal, water
year, or range of
years, for example,
water year 2024-
2025, use 2025
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Table 7-3 (DWR Table 7-1 Retail) shows the City’s historical supply reliability during the water years described above and includes both purchased surface water from MID and the City’s groundwater. The available supplies columns specify the volume and percentage of the City’s total water supply expected if the hydrology from that type of year were to repeat. Based on the operational yield estimate for the Modesto and Turlock Subbasins, it was assumed that groundwater supplies would not be reduced in dry years (up to 51,500 AFY).

The available surface water supply shown during each year type is consistent with Table 7-2 (DWR Table 7-1 Wholesale), which represents the maximum annual quantity of treated surface water the City may receive from the expanded MRWTP under the ARTDA (67,200 AF). In dry years, the maximum surface water volume available is calculated by applying MID’s actual reduction in water allotment for the applicable base year to this maximum volume of 67,200 AF. The surface water volumes reported in Table 7-3 are based on the total capacity available with the completion of the MRWTP Phase Two Expansion; the actual supply quantity available will be based on the City’s increase in demand and will need to conform to requirements of the ARTDA.

Table 7-3. Basis of Water Year Data (Reliability Assessment) (DWR Table 7-1 Retail) % of Average Supply
Average Year 1989-2025 100%
Single-Dry Year 2015 65%
Consecutive Dry Years 1st Year 2012 92%
Consecutive Dry Years 2nd Year 2013 92%
Consecutive Dry Years 3rd Year 2014 76%
Consecutive Dry Years 4th Year 2015 65%
Consecutive Dry Years 5th Year 2016 92%
118,700
77,040
Year Type
Base Year
If not using a calendar
year, type in the last year
of the fiscal, water year, or
range of years, for
example, water year 2024-
2025, use 2025
Available Supplies if
Year Type Repeats
Check the box if quantification of available
supplies is not compatible with this table and is
provided elsewhere in the UWMP.

Location: Section 7.2.1, Table 7-2 (DWR Table 7-1
Wholesale)
Volume Available (AF)
Quantification of available supplies is provided in this table as either volume only, percent only, or both.
109,300
109,300
NOTES: Volumes are rounded to the nearest 10 AF. Available volume includes both purchased water from MID and groundwater. The volume available for the average year is based on the maximum annual volume of treated surface water that the City may receive from the expanded MRWTP per the ARTDA (67,200 AF) consistent with DWR Table 7-1 Wholesale.

The volume available in dry years is based on the maximum volume of 67,200 AF multiplied by MID's actual reduction in water allotment to its customers during the respective base year. The actual supply quantity available in a given year will be based on the City’s increase in demand and will need to conform to requirements of the ARTDA. Available groundwater supply is based on the City's operational yield of 51,500 AFY and is not expected to be reduced in dry years. 89,810
77,040
109,300
DWR NOTES: Supplier may use multiple versions of Submittal Table 7-1 R if different water sources have different base years and the supplier chooses to report the base years for each water source separately. If a Supplier uses multiple versions of Submittal Table 7-1 R, in the "Note" section of each submittal table, state that multiple versions of Submittal Table 7-1 R are being used and identify the particular water source that is being reported in each submittal table.

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7.2.2 Water Service Reliability – Normal Year

7.2.2.1 City of Modesto
Table 7-4 (DWR Table 7-2 Retail) compares the City’s water supplies and projected demands under normal year conditions from 2030 to 2050. Total projected potable and non-potable demand is approximately 57,165 AF in 2030 and increases to 66,255 AF in 2050. As described in Chapter 4, the City’s potable demands have been estimated through 2050 based on projected population growth and recent water use trends in the City’s water service area. Non-potable groundwater use of 1,865 AFY from 2030 to 2050 is also included consistent with DWR Table 4-2 Retail.

Under normal year conditions, the City’s water supplies are assumed to consist of the following:
• MRWTP Phase One surface water supply of 33,600 AFY.
• MRWTP Phase Two Expansion surface water supply, assumed to be 5,110 AFY in 2030 (per the projected surface water use shown in DWR Table 6-9), with supplies gradually increasing through 2050 as development occurs within the City’s contiguous water service area, up to an additional total supply of 33,600 AFY for a total of 67,200 AFY. • Groundwater pumping from City’s local groundwater basins is assumed to provide 100 percent of the City’s remaining water demand (up to 51,500 AFY).

As shown in Table 7-4, the City has sufficient water supplies to meet projected demands under normal year conditions.

Table 7-4. Normal Year Supply and Demand Comparison (DWR Table 7-2 Retail)

7.2.2.2 MID
Table 7-5 (DWR Table 7-2 Wholesale) compares MID’s available urban water supply and wholesale demand under normal year conditions from 2030 to 2050. Projected wholesale demand is based on the City’s future surface water use reported in DWR Table 6-9 Wholesale, which assumes that 70 percent of the City’s total projected potable demands will be met with MID surface water. 2030 (AF) 2035 (AF) 2040 (AF) 2045 (AF) 2050 (AF)
Supply totals
(autofill from Submittal Table 6-9 R) 57,165 59,385 61,675 64,045 66,255 Use totals
(autofill from Submittal Table 4-2 R) 57,165 59,385 61,675 64,045 66,255 Surplus/(shortfall) 0 0 0 0 0
NOTES: Projected water use totals are consistent with DWR Table 4‑2 Retail and include non‑potable groundwater use of 1,865 AFY. Projected water supply includes normal year surface water and groundwater supplies, consistent with DWR Table 6-9 Retail.

DWR NOTES : Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3.
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MID’s urban wholesale demand is estimated to be approximately 38,710 AFY in 2030 and increase up to 45,073 AFY in 2050 due to growth within the City’s contiguous service area. This projected demand remains below the City’s maximum annual surface water allocation of 67,200 AFY under the ARTDA. Any future increase in supply will need to conform to requirements of the ARTDA.

As shown in Table 7-5, MID has sufficient treated surface water supply to meet the City’s projected surface water demands in normal years.

Table 7-5. Normal Year Supply and Demand Comparison (DWR Table 7-2 Wholesale)

7.2.3 Water Service Reliability – Single Dry Year
During dry years, the City’s groundwater supply is not anticipated to be reduced. However, MID’s surface water supply is conservatively projected to be reduced to approximately 38 percent of the City’s normal year water allotment. This projection is based on MID’s lowest historical water allocation to its customers that occurred in 2015, in which MID determined a water allocation of 16 inches per acre, or 38 percent of a full allocation, for all its customers.

7.2.3.1 City of Modesto
Table 7-6 (DWR Table 7-3 Retail) compares the City’s available supplies and projected demands under single dry year conditions from 2030 to 2050.

Under single dry year conditions, the City’s water supplies are assumed to consist of the following:
• Surface water supply from MID, conservatively assuming that 38 percent of the City’s projected normal year surface water allotment is available (refer to Table 7-5 [DWR Table 7-2 Wholesale]).

Supply totals
(autofill from Submittal Table 6-9 W) 38,710 40,264 41,867 43,526 45,073 Use totals
(see OPTIONAL Submittal Table 4-2 W) 38,710 40,264 41,867 43,526 45,073 Surplus/(shortfall) 0 0 0 0 0
NOTES: Projected wholesale supply available during normal year conditions is consistent with DWR Table 6-9 Wholesale. Projected wholesale use is based on the City's projected surface water use defined in DWR Table 4-2 Wholesale. Actual surface water supply availability and purchases may vary based on hydrologic condition and retail demands.

DWR NOTES : Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3. 2030 (AF) 2035 (AF) 2040 (AF) 2045 (AF) 2050 (AF)
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• Groundwater pumping from City’s local groundwater basins is assumed to provide 100 percent of the City’s remaining water demand (up to 51,500 AFY).

It is expected that the City’s water conservation efforts can reduce demand during dry year conditions.

For example, the City significantly reduced water demands during 2014 and 2015 and can implement similar water conservation measures to respond to future water supply shortages. However, to provide a more conservative assessment of water service reliability, the City’s projected water demands during a single dry year are assumed to be consistent with normal year demands.

Despite the significantly reduced surface water allocation from MID, the City anticipates having sufficient groundwater supply to meet remaining demands while staying within the City’s groundwater operational yield of 51,500 AFY. Non-potable demands of 1,865 AFY are also included in Table 7-6, consistent with DWR Table 4-2 Retail.

As shown in Table 7-6, the City’s water supplies are sufficient to meet projected demands under single dry year conditions.

Table 7-6. Single Dry Year Supply and Demand Comparison (DWR Table 7-3 Retail)

7.2.3.2 MID
Table 7-7 (DWR Table 7-3 Wholesale) compares MID’s available urban water supply and wholesale demand under single dry year conditions from 2030 to 2050.

MID’s projected urban water supply under single dry year conditions is conservatively assumed to be reduced to 38 percent of the City’s normal year surface water allotment. For planning purposes, it is assumed that supplemental surface water allocations via purchases or exchanges between the City and MID is unavailable.

Supply totals 57,165 59,385 61,675 64,045 66,255
Use totals 57,165 59,385 61,675 64,045 66,255
Surplus/(shortfall) 0 0 0 0 0
2030 (AF) 2035 (AF) 2040 (AF) 2045 (AF)
NOTES: Projected water use totals are consistent with DWR Table 4‑2 Retail and include non‑potable groundwater use of 1,865 AFY. Supply totals include the City’s surface water allocation expected under single dry‑year conditions and its groundwater supply. Under a single dry year, it is conservatively assumed that the City may receive 38 percent of its normal year surface water allocation from MID (DWR Table 7‑2 Wholesale). The remaining water demand is assumed to be met by the City's groundwater supply, which is not restricted during dry year conditions and remains below the City's operational yield of 51,500 AFY. 2050 (AF)
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Table 7-7 shows that in dry years with significantly reduced surface water allocations like the 2015 drought year, MID’s maximum available supply will be used to meet projected wholesale water demands. The City’s wholesale water demand is projected to match MID’s available supply because the City plans to maximize the use of treated surface water supply. The difference in MID’s urban water supply under single dry years (Table 7-7) and normal years (Table 7-5) will be met by increased groundwater pumping by the City.

Table 7-7. Single Dry Year Supply and Demand Comparison (DWR Table 7-3 Wholesale)

7.2.4 Water Service Reliability – Five Consecutive Year Drought During a five-consecutive-year drought, the City’s groundwater supply is not anticipated to be reduced.

However, based on the historical five-consecutive-year drought between 2012 and 2016, the City’s surface water allocations from MID are projected to be reduced to approximately 86 percent of its normal year allotment in the first year and second year, followed by a reduction to 57 percent of normal year allotment in the third year, 38 percent of normal year allotment in the fourth year, and 86 percent of normal year allotment in the fifth year.

The difference between dry year base supply and normal year supply may be available from MID as an allocation on an optional basis at additional cost to the City. However, for planning purposes, it is conservatively assumed that supplemental treated surface water supply is not available under five-consecutive-year drought conditions.
2030 (AF) 2035 (AF) 2040 (AF) 2045 (AF) 2050 (AF)
Supply totals 14,710 15,300 15,909 16,540 17,128
Use totals 14,710 15,300 15,909 16,540 17,128
Surplus/(shortfall) 0 0 0 0 0
NOTES: Under single dry year conditions, it is conservatively assumed that MID's surface water allocation to the City may be reduced to only 38 percent of the City's normal year wholesale demand (DWR Table 7-2 Wholesale). Projected wholesale use is set to available supply, as the City will maximize its use of available surface water and meet any remaining demands with its groundwater supply. For planning purposes, it is conservatively assumed that the supplemental purchase and exchange options are unavailable.

DWR NOTES: Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3.
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7.2.4.1 City of Modesto
Table 7-8 (DWR Table 7-4 Retail) compares the City’s available supplies and projected demands under five-consecutive-year drought conditions from 2030 to 2050.

Under five-consecutive-year drought conditions, the City’s water supplies are assumed to consist of the following:
• Surface water supply from MID, conservatively assuming that the City’s allotment ranges from 86 percent of its projected normal year allotment to as low as 38 percent of its projected normal year allotment
• Groundwater pumping from City’s local groundwater basins (up to 51,500 AFY) is assumed to provide 100 percent of the City’s remaining water demand It is expected that the City’s water conservation efforts can reduce demand during drought conditions.

For example, the City significantly reduced water demands during 2014 and 2015 and can implement similar water conservation measures to respond to future water supply shortages. However, to provide a more conservative assessment of water service reliability, the City’s projected water demands during a five-consecutive-year drought are assumed to be consistent with normal year demands.

Under these conditions, the City would increase groundwater pumping to meet the remaining water demands. Despite the significantly reduced surface water allocation from MID, the City anticipates having sufficient groundwater supply to meet remaining demands during all five dry years while staying within the City’s groundwater operational yield of 51,500 AFY. Non-potable demands of 1,865 AFY are also included in Table 7-8, consistent with DWR Table 4-2 Retail.

As shown in Table 7-8, the City’s water supplies are sufficient to meet projected demands under five-consecutive-year drought conditions.
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Table 7-8. Multiple Dry Years Supply and Demand Comparison (DWR Table 7-4 Retail)

7.2.4.2 MID
Table 7-9 (DWR Table 7-4 Wholesale) compares MID’s available urban water supply and wholesale demand under five-consecutive-year drought conditions from 2030 to 2050.

As previously described, MID’s surface water allocation is assumed to be reduced under five-consecutive-year drought conditions, with the most significant reductions occurring in the third and fourth year, representing the years 2014 and 2015 in the 2012-2016 drought. For planning purposes, it is conservatively assumed that supplemental surface water allocations via purchases or exchanges between the City and MID is unavailable.

Table 7-9 shows that in drought conditions with reduced surface water allocations like the 2012-2016 drought, MID’s maximum available supply will be used to meet projected wholesale water demands. The City’s wholesale water demand is projected to match MID’s available supply because the City plans to maximize the use of treated surface water supply. The difference in MID’s urban water supply under 2030 (AF) 2035 (AF) 2040 (AF) 2045 (AF) 2050 (AF) Supply totals 57,165 59,385 61,675 64,045 66,255
Use totals 57,165 59,385 61,675 64,045 66,255
Surplus/(shortfall) 0 0 0 0 0
Supply totals 57,609 59,843 62,149 64,487 66,255
Use totals 57,609 59,843 62,149 64,487 66,255
Surplus/(shortfall) 0 0 0 0 0
Supply totals 58,053 60,301 62,623 64,929 66,255
Use totals 58,053 60,301 62,623 64,929 66,255
Surplus/(shortfall) 0 0 0 0 0
Supply totals 58,497 60,759 63,097 65,371 66,255
Use totals 58,497 60,759 63,097 65,371 66,255
Surplus/(shortfall) 0 0 0 0 0
Supply totals 58,941 61,217 63,571 65,813 66,255
Use totals 58,941 61,217 63,571 65,813 66,255
Surplus/(shortfall) 0 0 0 0 0
NOTES: Projected water use is consistent with DWR Table 4-2 Retail and is linearly interpolated between each five-year increment. Projected water use also includes non‑potable groundwater use of 1,865 AFY. The City’s surface water supply from MID is projected to be reduced to approximately 86 percent of the City's normal year allocation in the first year and second year, followed by a reduction to 57 percent of normal year allocation in the third year, 38 percent of normal year allocation in the fourth year, and 86 percent of normal year allocation in the fifth year.

The remaining water demand is assumed to be met by the City's groundwater supply, which is not restricted during dry year conditions and remains below the City's operational yield of 51,500 AFY.

First year
Second year
Third year
Fifth year
DWR NOTES: Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3.

Fourth year
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five-consecutive-year drought conditions (Table 7-9) and normal years (Table 7-5) will be met by increased groundwater pumping by the City.

Table 7-9. Multiple Dry Years Supply and Demand Comparison (DWR Table 7-4 Wholesale)

7.3 DROUGHT RISK ASSESSMENT
In accordance with CWC §10612, urban water suppliers must conduct a DRA, which evaluates the risk of a severe drought occurring for the next five consecutive years (2026-2030). Supply conditions for the DRA are based on the five driest consecutive years on record, with adjustments to consider plausible changes in climate, regulations, and other locally applicable criteria.

This section reviews the data and methods used to define the DRA water shortage condition and evaluates each water source’s reliability under the proposed drought condition. Total water supplies during the five-year drought are then compared to projected normal year demands. Non-potable groundwater use of 1,865 AFY from 2030 to 2050 is also included in the DRA consistent with the City’s water service reliability assessment.

This DRA prepares the City for a potential water shortage and for implementation of its WSCP, if necessary.

Supply totals 33,291 34,627 36,006 37,432 38,763
Use totals 33,291 34,627 36,006 37,432 38,763
Surplus/(shortfall) 0 0 0 0 0
Supply totals 33,558 34,903 36,291 37,698 38,763
Use totals 33,558 34,903 36,291 37,698 38,763
Surplus/(shortfall) 0 0 0 0 0
Supply totals 22,419 23,316 24,242 25,163 25,692
Use totals 22,419 23,316 24,242 25,163 25,692
Surplus/(shortfall) 0 0 0 0 0
Supply totals 15,064 15,666 16,288 16,893 17,128
Use totals 15,064 15,666 16,288 16,893 17,128
Surplus/(shortfall) 0 0 0 0 0
Supply totals 34,360 35,730 37,147 38,497 38,763
Use totals 34,360 35,730 37,147 38,497 38,763
Surplus/(shortfall) 0 0 0 0 0
NOTES: MID's surface water allocation is projected to be reduced to approximately 86 percent of normal year allocation in the first year and second year, followed by a reduction to 57 percent of normal year allocation in the third year, 38 percent of normal year allocation in the fourth year, and 86 percent of normal year allocation in the fifth year. Projected wholesale use is set to available supply, as the City will maximize its use of available surface water and meet any remaining demands with its groundwater supply. For planning purposes, it is conservatively assumed that the supplemental purchase and exchange options are unavailable.

Third year
DWR NOTES: Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3.

Fourth
year
Fifth year
First year
Second
year
2030 (AF) 2035 (AF) 2040 (AF) 2045 (AF) 2050 (AF)
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7.3.1 Data, Methods, and Basis for Water Shortage Condition The water shortage condition for the DRA is the same as the five-consecutive-year drought described in Section 7.2.4. Since the DRA can be updated outside of the UWMP five-year plan cycle, the narrative description of the data and basis for the water shortage condition is repeated in this section.

As discussed in Chapter 6, the ARTDA between MID and the City includes a formula to reduce deliveries in drier than average years based on the number of inches allocated to MID’s agricultural customers. Based on the historical five-consecutive-year drought between 2012 and 2016, the City’s surface water allocations from MID are projected to be reduced to approximately 86 percent of its normal year allotment in the first year and second year, followed by a reduction to 57 percent of normal year allotment in the third year, 38 percent of normal year allotment in the fourth year, and 86 percent of normal year allotment in the fifth year. For planning purposes, it is conservatively assumed that supplemental surface water allocations via purchases or exchanges between the City and MID is unavailable.

In contrast, it is assumed that groundwater supplies will not be reduced in dry years. Based on the City’s groundwater operational yield estimates, it is assumed that groundwater supplies will be available up to 51,500 AFY throughout a five-year drought.

7.3.2 DRA Water Source Reliability
The City’s multiple dry year supplies include:
• Surface water supply from MID, conservatively assuming that the City’s allotment ranges from 86 percent of its projected normal year allotment to as low as 38 percent of its projected normal year allotment.
• Groundwater pumping from City’s local groundwater basins is assumed to provide 100 percent of the City’s remaining water demand (up to 51,500 AFY).

Table 7-10 summarizes the City’s available supplies for each year of the DRA. During the drought period, the City would maximize available surface water from MID and use groundwater to meet remaining water demands.

Table 7-10. City’s Projected Water Supplies for Drought Risk Assessment Supply Source
Projected Supply, AF
2026
(First Year)
2027
(Second Year)
2028
(Third Year)
2029
(Fourth Year)
2030
(Fifth Year)
MID Treated Surface Water(a) 26,696 28,345 19,879 13,981 33,291 Groundwater(b) 26,019 25,483 35,061 42,071 23,874
Total 52,715 53,828 54,940 56,053 57,165
(a) Based on the historical five-consecutive-year drought between 2012 and 2016, the City’s surface water allocations from MID are projected to be reduced to approximately 86 percent of its normal year allotment in the first year and second year, followed by a reduction to 57 percent of normal year allotment in the third year, 38 percent of normal year allotment in the fourth year, and 86 percent of normal year allotment in the fifth year.
(b) Based on groundwater supply needed to meet the remaining projected demand from 2026 through 2030. Actual groundwater supply may be up to 51,500 AFY per the City’s operational yield estimates for the Modesto and Turlock Subbasins and it is assumed the groundwater supply will not be reduced in dry years.
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7.3.3 Total Water Supply and Use Comparison
As shown in Table 7-11 (DWR Table 7-5), during a five-year drought beginning in 2026, the City’s supplies are adequate to meet projected demands through 2030, even without water conservation.

Table 7-11. Five-Year Drought Risk Assessment Tables
to Address Water Code Section 10635(b) (DWR Table 7-5)
2026 Total
Total Water Use (AF) 52,715
Total Supplies (AF) 52,715
Surplus/Shortfall w/o WSCP Action 0
2027 Total
Total Water Use (AF) 53,828
Total Supplies (AF) 53,828
Surplus/Shortfall w/o WSCP Action 0
2028 Total
Total Water Use (AF) 54,940
Total Supplies (AF) 54,940
Surplus/Shortfall w/o WSCP Action 0
2029 Total
Total Water Use (AF) 56,053
Total Supplies (AF) 56,053
Surplus/Shortfall w/o WSCP Action 0
2030 Total
Total Water Use (AF) 57,165
Total Supplies (AF) 57,165
Surplus/Shortfall w/o WSCP Action 0
NOTES: The City's projected demands are consistent with Table 4-7 and include both potable and non-potable demands.

DWR NOTES: Units of measure (AF, CCF, MG) must remain
consistent throughout the UWMP as reported in Submittal Table 2-

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7.4 WATER MANAGEMENT TOOLS AND OPTIONS
This section reviews the City and MID’s water management tools and options that would maximize the use of local water resources and minimize the need to import water from other regions.

7.4.1 City of Modesto
The City’s current water supply portfolio, consisting of local Tuolumne River water supplied by MID and groundwater, provides considerable flexibility and allows the City to maximize the use of local water resources.

The City currently maximizes its use of surface water supply from MID in normal and wetter years, although groundwater is also used to meet operational needs. By using surface water in-lieu of groundwater during these periods, the City effectively banks groundwater for future use in dry years. The City’s water supply planning incorporates sufficient surface water supplies to allow the City to meet the majority of the City’s demands through the use of surface water, allowing the in-lieu banking of groundwater and protecting the basin from overdraft and water quality degradation. At the same time, the City’s water supply planning incorporates sufficient groundwater capacity to meet demands during dry periods when MID’s surface water allocations are reduced.

When available, the City can also purchase additional treated surface water from MID (at a higher rate) or exchange groundwater for treated surface water during drought years. However, during the 2014 and 2015 drought years, the City did not purchase additional treated surface water supplies. Instead, the City chose to increase groundwater production and implement an aggressive water conservation program to help reduce water demands to match available supplies. The City’s demand management measures and water conservation program are described in Chapter 9.

To minimize vulnerability to groundwater quality issues, the City has also implemented strategies to maintain and enhance its groundwater supply capacity through a combination of well monitoring for early detection, well rehabilitation, wellhead treatment, and blending.

In the future, the City may consider implementation of an ASR program (as discussed in Chapter 6) to further enhance supply reliability. With an ASR program, the City may be able to inject surplus treated surface water supplies available in normal or wet years into the underlying groundwater basin and bank it for later extraction during dry years and/or use during seasonal demand peaking.

With these water management tools, the City does not currently foresee a need to import water from other regions.

7.4.2 MID
MID is primarily an agricultural water supplier, and it can reduce agricultural deliveries in drought years when surface water supplies are limited. MID also owns and operates approximately 93 groundwater production wells that are used to supplement surface water supplies during drought conditions. These groundwater wells are used for agricultural supply only and are not used for drinking water purposes. MID does not currently foresee a need to import water from other regions. #20..
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CHAPTER 8
Water Shortage Contingency Plan
This chapter discusses the City’s Water Shortage Contingency Plan (WSCP), seismic risk to City and MID facilities, and WSCP adoption procedures. To allow for WSCP updates to be made outside of the UWMP preparation process, the City’s WSCP is included in this plan as Appendix G. While the City and MID jointly prepared this plan, the WSCP focuses on the City only as an urban water supplier. MID is primarily an agricultural supplier and has prepared a separate 2025 AWMP, which includes its water shortage allocation policies and drought plan.

8.1 BACKGROUND
Water shortages occur whenever the available water supply cannot meet the normally expected customer water use. These shortages can be due to several reasons, including climate change, drought, and catastrophic events. Drought, regulatory action constraints, and natural and manmade disasters may occur at any time. A WSCP presents how an urban water supplier plans to respond to a water shortage condition and helps prevent catastrophic service disruptions.

In 2018, the California State Legislature enacted two policy bills, (SB 606 [Hertzberg] and AB 1668 [Friedman]) (2018 Water Conservation Legislation), to establish a new foundation for long-term improvements in water conservation and drought planning to adapt to climate change and the resulting longer and more intense droughts in California. The 2018 Water Conservation Legislation set new requirements for water shortage contingency planning; the City’s WSCP has been prepared to be consistent with these requirements. The City has made some minor updates to its 2020 WSCP with the preparation of this Joint 2025 UWMP to reflect the City’s updated Emergency Response Plan (ERP), as well as the County’s updated Local Hazard Mitigation Plan (LHMP).

8.2 CITY WATER SHORTAGE CONTINGENCY PLAN
Section 11-1.14 of the Modesto Municipal Code (MMC) supports the City’s WSCP, which describes the City’s strategic plan for preparing and responding to water shortages. The WSCP includes water shortage stages and associated shortage response actions, the City’s legal authorities, communication protocols, compliance and enforcement, and monitoring and reporting.

The City intends for its WSCP to be dynamic, so that it may assess response action effectiveness and adapt to foreseeable and unforeseeable events. Therefore, the City’s WSCP is included in this plan as Appendix G to allow for updates to be made outside of the UWMP preparation process. When an update to the WSCP is proposed, the revised WSCP will undergo the process described in Section 8.4.

8.3 WATER SUPPLY RELIABILITY ANALYSIS
This section provides the water supply planning analysis and reliability findings from this Joint UWMP. The discussion below includes a summary of the City’s existing and projected water use (from Chapter 4), existing and planned water supplies by source (from Chapter 6), and the water supply reliability assessment and the DRA (from Chapter 7).

The Joint UWMP indicates that the City can reliably meet its projected demands through 2050 in both normal and dry years. For a five-year drought, no water supply shortfalls are anticipated for the City. In response to any supply shortfalls that may occur, the City may declare a water shortage condition (as described in the City’s WSCP).
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For MID, the water service reliability assessment and DRA show that MID’s surface water supply allocations may be reduced in dry years. In these years, the City will rely on its groundwater supply, pumping more so that it can meet the projected water demand. While it will require additional groundwater pumping, the groundwater produced during these years is still less than its operational yield (refer to Chapter 6).

Climate conditions, regional and statewide water supply conditions, and actions by surrounding agencies may impact the City’s available water supply. A water shortage condition occurs when the supply of potable water available cannot meet ordinary water demands for human health and safety. The City may be able to foresee its water shortage condition in some cases, but an unforeseen sudden or emergency event (e.g., power outage or earthquake) may also cause a water shortage. In general, the City’s water supply conditions may be affected by the following:
• Groundwater quality
• Water supply facility failures (loss of treatment facilities, pumps, tanks, or transmission pipes) • Water supply facility vulnerability to seismic events • Local surface water availability (e.g., MID annual surface water allocations, Tuolumne River water curtailment during drought periods)
• Changing environmental and regulatory requirements (e.g., Don Pedro Reservoir FERC relicensing, Bay-Delta Plan, groundwater contaminant MCLs) • Climate change
The City plans for potential drought events annually. The City conducts an annual water supply and demand assessment in accordance with its WSCP to determine its water supply conditions for the current year and a potential subsequent dry year. The analysis conducted is in the context of the City’s water supply sources and reliability.

Seismic events present potential water supply interruptions as they may result in infrastructure failure.

Because earthquakes are common, well-tracked, and recognized as high-probability occurrences in California, UWMPs are required to include a seismic risk assessment and mitigation plan. The City’s plan is described in the section below.

8.3.1 Seismic Risk Assessment and Mitigation Plan
CWC §10632.5(a) requires that UWMPs include a seismic risk assessment and mitigation plan to assess and mitigate a water system’s seismic vulnerabilities. A Local Hazard Mitigation Plan (LHMP) or Risk and Resilience Assessment (RRA) may be incorporated in this UWMP to meet this requirement if it addresses seismic risk.

The City is located in Stanislaus County. As such, the Stanislaus County Multi-Jurisdictional Hazard Mitigation Plan (Stanislaus County HMP), provides relevant information regarding local seismic risk and is incorporated herein for reference. The Stanislaus County HMP is available on the Stanislaus County website:
https://oes.stancounty.gov/divisions/emergency-management/multi-jurisdictional-hazard-mitigation-plan. The Stanislaus County HMP was adopted in November 2022 and submitted to the Federal Emergency Management Agency, which found it in conformance with Title 44 Code of Federal Regulations Part 201.6 Local Mitigation Plans. The HMP is required to be updated every five years. #20..
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Seismic activity within Stanislaus County has been historically rare, and there are no records of major seismic activity originating in the County. As described in the Stanislaus County HMP, there are no known active faults within the County. However, ground shaking from earthquakes with epicenters elsewhere have been felt; most recently in 2021 by the 6.0 magnitude earthquake centered in the Little Antelope Valley, in Mono County. Additional details on the City’s seismic risk assessment and mitigation plan are provided in Appendix G.

The City developed an RRA in 2020 in accordance with the America’s Water Infrastructure Act (AWIA) and subsequently updated it in 2025. The RRA systematically evaluated the City’s assets, threats, and risks, and evaluated countermeasures that might be implemented to minimize overall risk to the system.

Vulnerability to natural hazards, including earthquakes, was assessed based on the City’s level of preparation/resilience, active response capability, and ability to recover. To protect the security of the City’s water system, the RRA is retained by the City as a confidential document.

The City’s efforts in addressing its few seismic vulnerabilities are in progress. For example, the City is proceeding with the design of a replacement tank within the Grayson area, since the existing tank cannot operate to its full capacity due to the freeboard requirements associated with sloshing height and the anchoring system of the existing tank.

8.4 ADOPTION, SUBMITTAL, AND AVAILABILITY
The City’s WSCP (Appendix G) is adopted concurrently with this Joint 2025 UWMP, by separate resolution.

Prior to adoption, a duly noticed public hearing was conducted. An electronic copy of the WSCP will be submitted to DWR within 30 days of adoption.

No later than 30 days after adoption, an electronic copy of the WSCP will also be available for public review and download on the City’s website. A copy will also be provided to Stanislaus County, City of Ceres, and City of Turlock.

The City’s WSCP is an adaptive management plan and is subject to refinements as needed to ensure that the City’s shortage response actions and mitigation strategies are effective and produce the desired results. When a revised WSCP is proposed, the revised WSCP will undergo the process described above for adoption by City Council and distribution to Stanislaus County, MID, City of Ceres, City of Turlock, the City’s customers, and the general public.
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CHAPTER 9
Demand Management Measures
This chapter describes MID and the City’s historical and existing water conservation efforts, status of implementation of Demand Management Measures (DMMs), and future water conservation implementation. Water conservation measures are a vital part of the MID and City’s overall plan to provide reliable, high-quality, and cost-effective water supply for its customers. MID and the City implement DMMs to sustainably manage the region’s water resources. If not mitigated, an increase in water demand and/or changes in water supplies due to climate change and other factors can reduce water service reliability. The implementation of DMMsimproves water service reliability and helps MID, the City, and State meet water conservation goals.

9.1 MID WATER CONSERVATION PROGRAM OVERVIEW
As noted previously, although MID is a wholesale water supplier to the City of Modesto, MID is primarily an agricultural water supplier. As such, it has also prepared a 2025 AWMP which describes Efficient Water Management Practices (EWMPs) being implemented in conjunction with its agricultural water system. As described below, although MID is not directly involved in the City’s implementation of urban water conservation measures, MID supports the City’s water conservation efforts.

9.2 MID DEMAND MANAGEMENT MEASURES
As discussed in Chapter 6, MID provides treated surface water supply to the City on a wholesale basis. The following wholesale DMMs are discussed in this section:
• Metering
• Public Education and Outreach
• Water Conservation Program Coordination and Staffing Support • Asset Management
• Wholesale Supplier Assistance Programs
• Other Demand Management Measures
For each of the above DMMs, the current program is described, followed by a description of how the DMM was implemented over the previous five years.

9.2.1 Metering
Treated water supplies provided to the City by MID are metered by MID at the Terminal Reservoir Pump Station when in flow-through mode and at the Treated Water Pump Station (TWPS) when in bypass mode.

The meters are calibrated annually. Metering was maintained from 2021 to 2025 and implementation of this DMM is ongoing. This DMM allows MID and the City to properly track their urban surface water use.

9.2.2 Public Education and Outreach
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9.2.3 Water Conservation Program Coordination and Staffing Support As previously noted, MID is primarily an agricultural water supplier and has developed a Conservation Program to encourage landowners, through financial incentives, to invest in physical improvements and management practices that conserve water. The long-term goal of the Conservation Program is to improve water management within MID’s water service area. As described in MID’s Draft 2025 AWMP, MID has designated their Assistant General Manager - Water Operations, as their Water Conservation Coordinator.

MID’s Water Conservation Coordinator does not focus on urban water conservation, as the City is responsible for implementing and managing the urban water conservation programs. However, MID staff coordinate regularly with City staff in support of the City’s urban water conservation efforts.

Between 2021 and 2025, MID maintained coordination with City staff, and implementation of this DMM is ongoing. This DMM provides for consistent water conservation messaging between MID and the City.

9.2.4 Asset Management
MID uses a Maintenance Management Program to help manage and coordinate maintenance activities at its facilities. Routine preventive maintenance work, non-routine service, and work orders are tracked such that MID’s Maintenance Supervisor can identify equipment issues that are starting to be problematic and proactively plan for replacement. MID generally does not replace equipment based on a manufacturer or industry recommended schedule, as they have found that through an aggressive preventive maintenance program, the service life of most equipment can be significantly extended.

This program was maintained by MID between 2021 and 2025, and implementation is ongoing.

Implementation of this program minimizes water loss, bolsters water system reliability, and improves efficiency in maintaining MID’s water system.

9.2.5 Wholesale Supplier Assistance Programs
Although MID is not directly involved with urban water demand reduction, MID strongly supports the City’s efforts through ongoing and continuous coordination between MID and the City, support of public outreach for water conservation through the City, and through the water use provisions contained in the October 2005 ARTDA between the City and MID.

MID maintains a Domestic Water Policy Committee with the City to oversee the management and operation of MRWTP. There are two advisory committees, the Policy Committee and the Technical Committee. The Policy Committee consists of two City Council members and two MID Board members and meets at least twice a year. Responsibilities of the Policy Committee include following MID’s Project budget and advising on major decisions. The Technical Committee, which meets monthly, is comprised of MID and City staff. The main purpose of the Technical Committee is to keep the City informed of MRWTP performance, scheduled maintenance, and any potential impacts to delivery.

MID has maintained its assistance for the City between 2021 and 2025, and this program is ongoing.

Implementation of this program helps MID and the City continue to coordinate and improve its water conservation efforts.

9.2.6 Other Demand Management Measures
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9.3 CITY OF MODESTO WATER CONSERVATION PROGRAM OVERVIEW The City has acknowledged the importance of water conservation and management and has implemented significant water conservation efforts during the drought years of 1976-1977, 1987-1992, 2012-2016, and 2021-2022. In March 1990, the City Council approved a Water Conservation Program (§ 11-1.14 of Title 11 of the MMC) which combined a strong education program with watering restrictions and prohibition of water waste. The City, with support from MID, has continued its Water Conservation Program and is committed to implementing water conservation measures for all its customer sectors.

In July 2021, the City updated its Water Conservation Plan, building upon the DMMs and conservation strategies identified and documented in the Joint 2020 UWMP. The overall goal of the Water Conservation Plan is to develop a system-wide water conservation plan containing acceptable water efficiency measures and an implementation plan which will decrease water use and water loss while using the most cost-effective methods. A copy of the City’s 2021 Water Conservation Plan is provided in Appendix H.

The City is currently in the process of developing an updated Water Conservation Plan, with the intent to better define the City’s Water Conservation Program and to plan for implementation in the future. The City plans to conserve water through public relations, education, customer service, and enforcement. The City strives to meet this challenge by working in a friendly, respectful, and positive manner with homeowners, businesses, and property managers.

As the City moves forward with its Water Conservation Plan, the City has also implemented its One Water Modesto program to communicate the value of the City’s water resources in all forms within the City. This program is described in Section 9.4.7.5 below.

The City’s SB X7-7 per capita water use target for 2020 was 228 GPCD. The DMMs that the City implemented allowed it to meet its target. In 2020, the City’s overall per capita water use was 175 GPCD, as presented in Chapter 5. The City anticipates continuing and expanding its Water Conservation Program to meet its future urban water use objectives.

9.4 CITY OF MODESTO DEMAND MANAGEMENT MEASURES
Retail water agencies are required to provide a description of the following six DMMs:
• Water waste prevention ordinances
• Metering
• Conservation pricing
• Public education and outreach
• Programs to assess and manage distribution system real loss • Water conservation program coordination and staffing support The City is also required to describe any other DMMs that it has implemented that have had significant impact on water use. This section provides a description of the DMMs that are currently implemented and those planned to be implemented in the future. For each DMM, the current program is described, followed by a description of how the DMM was implemented over the previous five years and future implementation plans.
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9.4.1 Water Waste Prevention Ordinances

9.4.1.1 DMM Description
The City prohibits water waste within its service area. The City’s WSCP (Appendix G) describes the water waste prevention measures and demand reduction actions.

The City has maintained and enforced basic water conservation measures and varying degrees of water waste prevention since 1990, when it adopted a Drought Contingency Plan. The City’s Drought Contingency Plan included four drought stages (I, II, IIA, and III) with increasingly stringent consumer water use restrictions for each stage. Over time, the City has amended the Drought Contingency Plan to meet its water use objectives.

With the adoption of the City’s 2021 WSCP, the City’s Drought Contingency Plan has since been replaced to meet State requirements for water shortage contingency planning. To provide a consistent regional and statewide approach to conveying the relative severity of water supply shortage conditions, the 2018 Water Conservation Legislation mandates that water suppliers plan for six standard water shortage levels that correspond to progressive ranges of up to 10, 20, 30, 40, 50 percent, and greater than 50 percent shortages from the normal supply condition. The City’s WSCP (Appendix G) provides additional details on the water use restrictions for each water shortage level.

The City Council, by resolution, can declare the existence of a water shortage and adopt revised or additional water use prohibitions and consumption reduction methods while the water shortage remains in effect.

9.4.1.2 Implementation over the Past Five Years
Over the past five years, the City has remained in Stage 2 of the City’s six standard water shortage levels, including throughout the 2021-2022 drought period. This designation reflects the City’s “Conservation as a Way of Life” approach, under which a three-day-per-week watering schedule is maintained as a baseline conservation measure. It does not indicate that the City was experiencing an active water supply shortage during this period.

9.4.1.3 Plans for Continued Implementation
The City will continue to enforce its rules and regulations associated with water waste by having the Utilities Department perform site visitsthroughout the service area. The effectiveness of this program will be evaluated based on the number of violations observed, as well as the overall demand reduction associated with invoking drought restrictions. Presently, the City’s Utilities Department employs four part-time water patrols. They patrol during the summer months enforcing outdoor water restrictions.

Implementation of this DMM is ongoing and expected to help the City achieve its water use objectives by minimizing the non-essential uses of water so that water is available to be used for human consumption, sanitation, and fire protection.
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9.4.2 Metering

9.4.2.1 DMM Description
In 2004, the California Legislature passed AB 2572, requiring all water suppliers to install water meters on all customer connections by January 1, 2025. The City has been installing meters on new homes since the City Council enacted the MMC 11-1 on May 14, 19911, and in 2005 the City changed its water rate structure to include a volumetric rate charge. All new development in the City has had meters installed since 1991.

9.4.2.2 Implementation over the Past Five Years
Over the past five years, the City completed its conversion of all unmetered accounts within the water system to metered accounts. As of 2024, the City’s water system has been fully metered.

9.4.2.3 Plans for Continued Implementation
The City will require all future connections to be metered and billed based on the volume of water used, as discussed in further detail under Section 9.4.3. The City will monitor water usage characteristics of its customers and focus water conservation efforts on high water users.

9.4.3 Conservation Pricing

9.4.3.1 DMM Description
The City’s water rate structure encourages water conservation by incorporating a volumetric charge in addition to the fixed meter charge. Consequently, water usage reductions directly reduce cost to the customer, while excessive water use results in increased costs.

As described above, as of 2024, all the City’s water services are now metered. Previously, unmetered residential customers were billed based on a flat rate based on lot size. As customers have become metered, they have been converted from a flat rate charge to the metered charge.

9.4.3.2 Implementation over the Past Five Years
The City’s current water rate structure as of January 1, 2026 is shown in Table 9-1. The City’s water rate structure includes a fixed meter charge and a uniform volumetric charge determined by water usage. The uniform volumetric charge currently in effect is based on non-drought supply conditions. During a drought, the City may enact drought rates, which would temporarily increase customers’ volumetric charge. Drought rates are designed to support the City’s financial stability and help ensure adequate funding for water utility operations during periods of water shortages and reduced water sales. The City did not implement drought rates during the 2021-2022 drought. 1 Though the City did start installing meters in 1991, these meters were not read for volumetric billing purposes and these homes remained on a flat rate billing method until 2005 when, as a result of AB 2572 mandating all homes to be metered by 2025, the City started installing meters on existing homes and changed its rate structure to bill metered homes on a volumetric basis.
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Table 9-1. City of Modesto Current Water Rates and Charges(a) Metered Charges (Residential & Commercial) Monthly Rate, dollars Non-Drought Volumetric Charge ($/hcf)(b) 2.30
Fixed Meter Charges
5/8-inch – ¾-inch 28.86
1-inch 42.09
1 ½-inch 75.19
2-inch 114.89
3-inch 240.63
4-inch 425.92
6-inch 869.30
8-inch 1,597.25
10-inch 2,523.73
12-inch 3,317.84
(a) City of Modesto Current Water Rate (as of January 1, 2026) from City of Modesto website. (b) Non-drought rate per hundred cubic feet (hcf).

9.4.3.3 Plans for Continued Implementation
Implementation of this DMM is expected to help the City achieve its water use objectives while also ensuring adequate funding for water utility operations and improvements. As required, the City will evaluate the need to adjust rates and/or rate structures in the future to ensure continued service to its customers while encouraging water efficiency. The City will evaluate the effectiveness of its rates by tracking changes in unit water use resulting from rate increases.

9.4.4 Public Education and Outreach

9.4.4.1 DMM Description
To promote water conservation, the City seeks to foster sustainable changes in behavior, not just temporary responses to drought. Water conservation information is distributed to the public through a variety of methods including personal contact, brochures, radio and television public service announcements, a dedicated conservation website, bill inserts, exhibits at community events, school presentations and videos. A water conservation telephone line is available to provide residents with any additional information they might request regarding water conservation.

The City also coordinates with the media to better inform the public. Media coverage of the City’s water conservation program is provided through public service announcements on television and radio in both English and Spanish, live interviews and recorded cable television. Recorded video content on water conservation and efficient landscaping practices are available from the Utilities Department, Water Services Division for use by the public. Copies of these videos have been donated to the Stanislaus County Library and several landscape nurseries in the City. The City also works with its local newspaper, the Modesto Bee, to provide frequent and extensive coverage of current water conditions within the Modesto area.
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9.4.4.2 Implementation over the Past Five Years
Over the past five years, the City has attended and promoted water conservation at the Stanislaus County Home and Garden Show, Modesto Home Improvement Show, Earth Day in the Park, and Public Works Day. At these events, the City promotes its water rebates, hands out water-saving items (e.g., shut-off nozzles, smart irrigation controllers, dye tablets), and provides conservation kits for both children and adults. There are two conservation kits the City distributes for different purposes, which include:
• Children’s Water Conservation Kit
— A Water Wise bag
— BE WATER WISE coloring book with crayons and stickers — Water conservation website links for parents
• Adult Water Conservation Kit
— 15 Ways to Use Water Wisely bag
— Water Conservation slide guide
— Use Water Wisely note pad
— Water Conservation Brochures
— Water conservation website links
In addition, each year City staff give presentations to students at elementary schools in Modesto’s service area. During these presentations, students are taught about the water cycle and water conservation and receive Water Conservation Kits. The City’s Water Conservation Specialists have also met with school district principals to encourage participation in the program, as it focuses on water conservation while incorporating State content standards. Two American Water Works Association (AWWA) publications, “Splash” and the “Story of Water,” as well as the video “Water Follies,” are used in conjunction with school programs and other community events. Elementary school students are particularly receptive to the conservation message, and they share that message with their parents. Though school presentations are designed for fifth graders, similar presentations are given to junior and high school students upon request.

9.4.4.3 Plans for Continued Implementation
The City and MID will continue to implement the public education and outreach strategies as described above. Implementation of this DMM is expected to help the City achieve its water use objectives by educating water users about the value of water, the importance of improving water use efficiency, and avoiding water waste.

9.4.5 Programs to Assess and Manage Distribution System Real Loss

9.4.5.1 DMM Description
The City has various programs to assess and manage distribution system losses including annual water loss audits and other distribution system maintenance programs. A water audit is a process of accounting for water use throughout a water system to quantify the unaccounted-for water (also referred to as non-revenue water). Unaccounted-for water is the difference between metered production and metered consumption on a system-wide basis. The City performs an annual water audit for each of its PWSs that conforms to the AWWA Manual M36. The City’s water loss audits for each of its PWSs over the past five years are included in Appendix E.
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9.4.5.2 Implementation over the Past Five Years
Repair and maintenance of the water distribution system are a priority for the City. The City has various operations and maintenance programs that maximize efficiency of water distribution system operations and minimize water losses. These programs include using SCADA systems to monitor groundwater and surface water production, responding quickly for water main leak repairs, annual pump efficiency testing, and water quality efforts including main flushing and water quality testing.

Daily water production from the City’s wells and the MRWTP is recorded and used to monitor water use.

Additionally, the City maintains records of main breaks which are used to identify mains to be replaced and estimate system water loss. The City’s finance system contains a leak detection code that will flag continuous water use. Work orders are created for these “leak code” accounts so the City can investigate and repair any leaks within the City’s right-of-way. Customers are notified of possible leaks on their property and must repair confirmed leaks within 24 hours of notification. Failure to comply with the 24-hour repair window results in fines.

Water line workers are also responsible for identifying system leaks, in addition to excessive water waste and standing water. At the customer’s request, City staff will investigate and, where appropriate, repair leaks within the City’s right-of-way. In addition, staff conduct repairs of water line leaks and replace or repair meters. A crew will repair leaks in areas where leak detection equipment has pinpointed hidden leaks.

Meter verifications at the well sites are routinely performed to confirm that meters are within manufacturer specifications. Pump efficiency tests are completed annually. Repairs are promptly made on pumps showing decreased efficiency, and flow meters found to be inaccurate or exhibiting signs of wear are promptly replaced. Well efficiency is consistently tracked through the City’s SCADA system.

The City uses Lucity, a maintenance management system, to improve the efficiency of completing work orders, managing imported records and scheduling maintenance. In addition, the City’s customers are able to use automatic meter reading (AMR) technology to help them detect leaks themselves. Leak reports and repairs are also logged in GIS to document and track the frequency of issues by location and to aid in identifying, planning, and prioritizing which areas need to be budgeted for water main and service line replacements. These programs are effective tools for providing customers with an efficiently operated and dependable water distribution system.

Through the City’s Annual Pipe Replacement Program, City Engineering staff work in coordination with City Operations crews to identify aging and leaking pipelines and replace those pipelines. The Annual Pipe Replacement Program has allowed the City to identify areas within its service area that are problematic with high percentages of leak and repair frequency. Based on these findings, the City has developed a prioritized replacement schedule and budget to systematically address these problem areas. Over the past five years, the Annual Pipe Replacement Program has resulted in the replacement of approximately

31.7 miles of water mains.

9.4.5.3 Plans for Continued Implementation
Implementation of this DMM is ongoing and is a vital element of the City’s Water Conservation Plan. This effort will help the City achieve its water use objectives by quickly identifying sources of water loss so repairs can be conducted and losses minimized.
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9.4.6 Water Conservation Program Coordination and Staffing Support

9.4.6.1 DMM Description
The City maintains two Water Conservation Specialist positions as part of its Water Services Division in the Utilities Department. The Water Conservation Specialists’ role is to develop, implement, and manage the City’s water conservation program and to coordinate with ongoing conservation programs in other departments and other agencies, including MID. Specifically, the Water Conservation Specialists perform the following tasks:
• Runs school education outreach programs
• Trains and directs activities of other staff assigned to water conservation functions • Provides conservation information to residents and commercial businesses and coordinates the development of uniform conservation policies and enforcement • Develops, recommends and maintains various media sources for providing conservation information to both internal and external customers
• Plans, coordinates and administers various day-to-day activities pertaining to the City’s Water Conservation Program
• Promotes the efficient use of the City’s water supply by residential, irrigation, industrial, commercial, public agencies, and other customers to ensure sufficient pressure throughout the system for fire protection and other essential City services • Investigates and identifies compliance issues and communicates with regulatory agencies as required
The Water Conservation Specialists also have an administrative office assistant and four to six temporary (seasonal) employees to help with the water conservation program. The administrative office assistant helps with phone calls, answers questions, and assists with the workflow of the temporary-seasonal employees.

The seasonal employees help with water waste enforcement and public education. In addition, there are other staff members of the City’s Water Quality Division that help with conservation program tasks.

However, these staff members are not specifically designated to the water conservation program.

9.4.6.2 Implementation over the Past Five Years
Over the past five years, the City has maintained the Water Conservation Specialist positions and the water conservation program team to execute the DMMs described in this chapter.

9.4.6.3 Plans for Continued Implementation
The City plans to continue maintaining the position of the Water Conservation Specialists.

Implementation of this DMM is ongoing and expected to help the City achieve its water use objectives by making water conservation and implementation of the City’s water conservation program a priority among City employees.
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9.4.7 Other Demand Management Measures
In addition to the six DMMs described above, the City implements the following programs:
• Residential conservation programs
• Commercial, industrial, institutional (CII) customer conservation programs • Large landscape irrigation conservation programs
• Rebate programs
In addition to the above listed programs, the City has started the One Water Modesto program, an initiative to align internal staff from various departments to communicate the value of water resources within the City.

9.4.7.1 Residential Conservation Programs

9.4.7.1.1 DMM Description
The City offers several water conservation services to its residential users as described below. These services are complemented by the City’s rebate programs, described in Section 9.4.7.4. The City offers these services upon request at no cost to customers.
• Water Surveys: Water surveys for residential users help raise awareness of water conservation in the home and help conserve water during everyday use. Surveys are offered via mailers, bill inserts and/or the City’s website. Further, the City identifies the high residential water users in its service and focus on those users.

Service technicians and/or City interns visit the residential users to provide leak detection assistance by performing surveys that include both indoor and outdoor investigations and offer suggestions for both single family and multi-family residences to improve water use efficiency. They identify water efficiency rebates, discussed in Section 9.4.7.4, for which the resident may qualify. Lawn watering guides are also distributed. The water savings from using lawn watering guides is estimated to be 20 percent per household with automatic sprinklers and 10 percent for manual systems.
• Sprinkler Timer Programming: Upon request, water conservation staff members are available to set sprinkler timers, adjust sprinkler heads, and provide minor advice on sprinkler systems. Staff members agree that the small amount of extra time spent assisting customers creates goodwill, ultimately reducing the likelihood of enforcement staff having to return in the future.
• Water Conservation Kits: The City distributes Water Conservation Kits through its Water Conservation Program. Conservation kits are also distributed after each water conservation presentation to both adults and children. Each kit contains one toilet displacement bag, dye tablets to detect toilet leaks, general conservation information, and installation instructions.

When using the displacement bag in a standard toilet, approximately one gallon of water is saved with each flush. It is estimated that 20 percent of all toilets leak, and that the average leak wastes nearly 47 gallons a day. Using the dye tablet will help customers detect those leaks. #20..
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9.4.7.1.2 Implementation over the Past Five Years
The effectiveness of residential water survey program is measured by monitoring the number of completed water survey assistance requests. Between 2021 and 2025, City staff completed approximately 10,705 water survey assistance requests in total (i.e., residential and CII combined). Between 2021 and 2025, City staff distributed approximately 20,000 water conservation kits.

9.4.7.1.3 Plans for Continued Implementation
The City plans to continue the above residential conservation programs to meet future water use objectives.

9.4.7.2 Commercial, Industrial, Institutional Customer Conservation Programs

9.4.7.2.1 DMM Description
The City has adopted the Commercial Green Building Code for its CII customers. The Commercial Green Building Code requires higher water use efficiency standards. Furthermore, the City offers water conservation survey services to new and existing CII users as described below. The City offers these services upon request at no cost to customers.
• New CII Users: During the building permitting process, wastewater and water system connection fees are estimated for applicants based on anticipated water use. The applicant/incoming customer may potentially achieve cost savings in fees by finding ways to reduce their projected water consumption. The City encourages applicants to conduct a self-audit of their operations and equipment and determine how water efficiency may be achieved. The City has developed tools and information sources to inform incoming CII customers of these potential savings.
• Existing CII Users: The City implemented a similar effort to inform existing CII users of potential financial savings through self-audits. The City developed a formal survey program for CII accounts that consist of water use surveys (performed upon request) and evaluations of operations and equipment. Recommended efficiency measures are provided, along with water efficiency rebate information, described in Section 9.4.7.4, for which the users may qualify.

The City’s Environmental Compliance Division, which handles wastewater discharge permits among other regulatory tasks, is instrumental in assisting larger CII users with determining water savings measures to reduce wastewater discharge impacts. The City estimates that the combined cost savings from both water and wastewater charges offset the cost of the self-audit.

9.4.7.2.2 Implementation over the Past Five Years
The effectiveness of the CII water survey program is measured by monitoring the number of completed water survey assistance requests. Between 2021 and 2025, City staff completed approximately 10,705 water survey assistance requests in total (i.e., residential and CII combined).

9.4.7.2.3 Plans for Continued Implementation
The City plans to continue the above CII conservation programs to meet future water use objectives. The City encourages staff to attend training that would increase their knowledge of water saving measures. #20..
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9.4.7.3 Large Landscape Irrigation Conservation Programs

9.4.7.3.1 DMM Description
The City strongly supports water efficiency for outdoor water use and has adopted the State’s Model Water Efficient Landscape Ordinance (MWELO) for new and retrofitted landscapes. Further, the City has implemented several conservation programs internally and for its customers to improve water efficiency for large landscape irrigation.
• ETo-Based Irrigation System at Parks: The Utilities Department, Water Services Division has implemented efficient ETo-based irrigation systems at many City parks. ETo-based irrigation systems adjust irrigation schedules based on weather forecasts and evapotranspiration data. Recently, the system has expanded to include more parks and public land. The City has 10 staff who, in addition to other tasks, serve as landscape auditors to oversee landscaping maintenance of the City’s parks and golf courses.
• Match Water Quality with Use: The landscape irrigation for approximately 10 percent of the City’s parks have been converted to use shallow groundwater instead of treated surface water and groundwater. The shallower aquifers in the area are generally not tapped for potable water uses due to the presence of contaminants that require treatment. This strategy serves as both a cost savings to the Parks Department and as a means by which available potable water supply sources can be conserved for potable uses. Park irrigation still utilizes conservation measures, regardless of water source, but these shallow, water-bearing aquifer zones would otherwise go unused in urban areas. • Large Landscape Surveys: The City formally offers surveys to large landscape accounts.

Under this program, City staff visit customers’ sites and recommend site-specific efficient irrigation schedule and improvements. City staff provides each customer with an ETo-based water use budget equal to no more than an average of 70 percent of the annual average local ETo per square foot of landscape area. Recreational areas, such as parks, may require additional water than allotted in the budget, but their use still may not exceed 100 percent of ETo on an annual basis.
• Landscape and Irrigation Plans: All commercial and residential projects that get a building permit and have more than 500 square feet (sf) of landscaping are required to submit a landscape and irrigation plan, which is reviewed by the Parks Planning and Development Division to ensure that MWELO requirements are followed. In addition, during construction of any commercial or residential projects, Parks Planning and Development Division staff perform inspections to ensure that the project is being constructed according to plans and in accordance with the MWELO requirements.
• Tracking Customers with Water Use Budgets: The City provides notices each billing cycle to the accounts with water use budgets showing a comparison between the budget and actual water consumption. For customers that are 20 percent over budget, the City offers further technical assistance and encourages participation in the smart irrigation controller rebate program, described in Section 9.4.7.4.

9.4.7.3.2 Implementation over the Past Five Years
The City does not separately track the number of large landscape surveys completed; however, they are included in the 10,705 water survey assistance requests completed between 2021 and 2025. #20..
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9.4.7.3.3 Plans for Continued Implementation
The City anticipates achieving the greatest water savings per customer by focusing assistance on large landscape water users. The City plans to continue implementing the conservation programs described above to meet future water use objectives.

9.4.7.4 Rebate Programs

9.4.7.4.1 DMM Description
The City maintains rebate programs for residential and CII customers. The rebates are intended to encourage customers to replace or improve existing appliances, equipment, or facilities to improve water efficiency. These rebates are promoted on the City’s website and offered when City staff provides water conservation surveys for customers.

Customers are reimbursed for a portion of the cost in making water efficient improvements. The rebates are subject to water conservation staff inspections and the terms and conditions provided on the City’s water conservation website. The rebates are provided to the customers upon confirmation that the replacement or improvement is complete. The City’s rebate programs are summarized in Table 9-2, along with the rebate amount.

9.4.7.4.2 Implementation over the Past Five Years
The City’s rebate programs had active customer participation between 2021 and 2025. The number of units replaced or installed under each program is listed in Table 9-2. The City’s High Efficiency Clothes Washer and High Efficiency Toilet Programs were popular with customers over the past five years. The Rain Barrel program had minimal participation; thus, the City ended the program on June 30, 2020.

Table 9-2. City of Modesto Rebate Programs from 2021 to 2025(a) Program Rebate Incentive
Number of Replaced/
Installed Units
Turf Replacement $2 per sf
(maximum $6,000 per account)
1,342,600 sf/
(1,071 customers)
High Efficiency Clothes Washer $200 maximum per account 673 clothes washers High Efficiency Toilet $100 maximum per toilet 639 toilets Drip Irrigation $0.50 per sf
(maximum $1,000 per account)
545,900 sf/
(289 customers)
Smart Irrigation Controller $75 per account 387 controllers Source: Data from City’s Water Conservation staff, April 2026. (a) Fiscal Years Ending 2021-2025.
sf = square feet

9.4.7.4.3 Plans for Continued Implementation
The City anticipates continuing many of these rebate programs, depending on customer participation and funding availability, to achieve its future water use objectives. #20..
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9.4.7.5 One Water Modesto Program
Over the past five years, the City developed the One Water Modesto program, an initiative to internally align staff from various departments to communicate the value of the City’s water resources. Through One Water Modesto, the City takes a holistic approach to its water resources, including potable water, storm water, groundwater, surface water, wastewater, and recycled water. By providing consistent messaging from staff, the City seeks to improve awareness of water resources and infrastructure through public outreach and engagement. Goals of the One Water Modesto program include:
• Stimulating economic development;
• Developing public and private partnerships;
• Improving water resource management and policies;
• Promoting civic pride;
• Ensuring regulatory compliance; and
• Fostering confidence in the City’s utilities.

The One Water Modesto program is ongoing. The City continues to integrate this program in its operational practices and messaging with its staff and customers. Implementation of this program helps the City staff and its customers elevate their mindset on the value of water, protecting water sources, and the environment. This program is anticipated to help the City attain its water use objectives and maintain the reliability of its water supplies.

9.5 CONTINUED IMPLEMENTATION OF DMMS
The City is an active member of the California Water Efficiency Partnership (CalWEP) establishing a firm commitment to the implementation of DMMs to conserve its water supplies. Water conservation measures are a vital part of the City’s overall plan to provide a reliable, high-quality, and cost-effective water supply to its customers. The City plans to continue implementation of its DMMs into the future.

The City plans to comply with the Making Conservation a California Way of Life regulation to meet its UWUOs, and to submit annual water loss audits in compliance with SB 555 water loss performance standards as part of its Water Loss Control Program.

The City has successfully implemented several water conservation measures to educate its water customers and encourage the efficient use of available water supplies. The City plans to continue implementing the DMMs described in this chapter to help achieve its water use objectives and researching emerging technologies and conservation strategies that may bolster its existing DMMs.

The City continually monitors and assesses the success of its water conservation programs to determine if additional measures are needed to meet its own water conservation goals and regulatory water use objectives.

9.5.1 Meeting Urban Water Use Objectives
The Making Conservation a California Way of Life legislation established a new framework for improvements in long-term urban water use efficiency. This legislation builds on the statewide 2020 water conservation targets set under SB X7-7 (CWC §10609.2(d)). Under the Legislation, the State Water Board, in coordination with DWR, was required to adopt urban water use efficiency standards, variances, and performance measures by June 30, 2022.
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On July 3, 2024, the State Water Board adopted the Making Conservation a California Way of Life Regulation. As part of this regulation, Urban Water Suppliers will be held to annual UWUOs. The City is required to calculate its UWUO annually, which is a sum of water efficiency budgets for the following uses:
• Residential indoor water use
• Residential outdoor water use
• Real water loss
• CII landscapes with dedicated irrigation meters (DIMs) The City’s UWUO is calculated using statewide efficiency standards, and considers the City’s water service area population, climate, and landscape area. Efficiency standards for the different components will progressively decrease from 2025 to 2040. Variances and adjustments may be allowed for special cases such as seasonal population fluctuation, special landscape areas (sports fields and recreational areas), potable recycled water use, and agricultural uses. Figure 9-1 summarizes the components that make up the UWUO.

Source: California Water Efficiency Partnership. May 2024. Making Conservation a California Way of Life Standards Framework Cut Sheet.

Figure 9-1. Urban Water Use Objective Components
In addition to calculating and complying with the UWUO, beginning in 2027, the City will need to classify its CII properties, and begin deploying best management practices (BMPs) for indoor and outdoor CII water use. These CII performance measures are intended to enable water-usage benchmarking per CII classification category, as well as establish BMPs for indoor and outdoor CII water use.

9.5.2 Annual Water Use Reporting
Starting in 2024, the City is required to calculate its UWUO, compare its actual water use to its UWUO, and provide an Annual Water Use Report to the State by January 1 of each year. Reporting is based on fiscal year data. Each year the City will need to recalculate its UWUO and meet the applicable UWUO for the year. If it does not meet its UWUO, the City will need to develop a plan and intensify or implement demand management actions to improve water use efficiency.

The City submitted its Fiscal Year 2024/2025 Annual Water Use Report to the State on December 30, 2025, and will continue to prepare this report annually to assess its progress towards achieving its UWUO. #20..
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10-1 City of Modesto/MID
Joint 2025 Urban Water Management Plan
May 2026
CHAPTER 10
Plan Adoption, Submittal, and Implementation
This chapter provides information regarding the notification, public hearing, adoption, and submittal of the City and MID’s Joint 2025 UWMP. It also includes discussion on plan implementation and the process of amending the UWMP and the WSCP.

10.1 INCLUSION OF ALL 2025 DATA
As indicated in Section 2.4 of this plan, the City and MID use a calendar year for urban water supply and demand accounting, and therefore this plan includes data through December 2025.

10.2 NOTICE OF PUBLIC HEARING
In accordance with the UWMP Act, the City and MID must provide an opportunity for the public to provide input on this Joint 2025 UWMP. The City and MID must consider all public input prior to its adoption.

There are two audiences to be notified for the public hearing: cities, counties, and neighboring water districts; and the public.

10.2.1 Notices to Cities and Counties
As discussed in Section 2.5, the City and MID provided greater than a 60-day notice regarding the preparation of its Joint 2025 UWMP and WSCP to the County as well as neighboring cities, communities, and water agencies as listed below:
• Stanislaus County
• City of Turlock
• City of Ceres
• City of Oakdale
• City of Riverbank
• City of Waterford
• Grayson Community Service District
• South Modesto Municipal Advisory Council
• Turlock Irrigation District
• Oakdale Irrigation District
• Stanislaus County Farm Bureau
• Stanislaus and Tuolumne Rivers Groundwater Basin Association GSA • West Turlock Subbasin GSA
• East Turlock Subbasin GSA
• Northwestern Delta-Mendota GSA
The notices of preparation are included as Appendix D.

Upon substantial completion of this Joint 2025 UWMP and WSCP, the City and MID coordinated internally and provided a notice of public hearing (Appendix D) to the County and cities of Modesto, Turlock, and Ceres, as noted in Table 10-1 (DWR Table 10-1 Retail) and Table 10-2 (DWR Table 10-1 Wholesale). #20..
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Table 10-1. Notification to Cities and Counties (DWR Table 10-1 Retail) Table 10-2. Notification to Cities and Counties (DWR Table 10-1 Wholesale) City Name 60 Day Notice
Drop Down (yes/no)
Notice of Public
Hearing
Drop Down (yes/no)
City of Modesto Yes Yes
City of Turlock Yes Yes
City of Ceres Yes Yes
County Name
Drop Down List
60 Day Notice
Drop Down (yes/no)
Notice of Public
Hearing
Drop Down (yes/no)
Stanislaus County Yes Yes
City Name 60 Day Notice
Drop Down (yes/no)
Notice of Public Hearing
Drop Down (yes/no)
City of Modesto Yes Yes
City of Turlock Yes Yes
City of Ceres Yes Yes
County Name
Drop Down List
60 Day Notice
Drop Down (yes/no)
Notice of Public Hearing
Drop Down (yes/no)
Stanislaus County Yes Yes
Check the box if the Supplier has notified more than 10 cities or counties in accordance with Water Code Sections 10621 (b) and 10642.

Completion of the table below is not required. Provide a separate list of the cities and counties that were notified.

Provide the page or location of this list in the UWMP.

Check the box if the Supplier has notified 10 or fewer cities or counties.

Complete the table below.
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10.2.2 Notice to the Public
As noted in Table 10-1 and Table 10-2, the City and MID issued a notice of public hearing to the public.

The City and MID also provided a public review period following the notice and prior to adoption of the Joint 2025 UWMP and WSCP to allow ample time for public comments to be prepared and received.

A notice of availability and public hearing was issued in accordance with Government Code § 6066 and was published twice in the City’s local newspaper, the Modesto Bee, to notify all customers and local governments of the public hearing. In addition, the notice was posted on the City and MID websites. A copy of the published Notice of Public Hearing is included in Appendix D.

10.3 PUBLIC HEARING AND ADOPTION
The City and MID encouraged community participation in the development of this Joint 2025 UWMP, including the City’s WSCP, using public notices and web-based communication. The notice included the time and place of the public hearing, as well as the location where the plan is available for public inspection.

10.3.1 Public Hearing
The City and MID each held public hearings for the Joint 2025 UWMP on MM DD, 2026. The public hearing provided an opportunity for all City and MID water customers and the general public to become familiar with the Joint 2025 UWMP and the City’s associated WSCP and ask questions about the City and MID’s continued plans for providing a reliable, safe, high-quality water supply and mitigating potential water shortage conditions.

Copies of the draft Joint 2025 UWMP were made available for public inspection at the City’s Utilities Department, the MID Board Secretary’s office, and on the City and MID websites. Copies of the City’s draft WSCP were also made available for public inspection at the City’s Utilities Department and on the City website.

10.3.2 Adoption
Subsequent to the public hearings, this Joint 2025 UWMP and WSCP were adopted by both the Modesto City Council and the MID Board of Directors at their respective meetings on MM DD, 2026. Copies of the adopted resolutions are included in Appendix I.

10.4 PLAN SUBMITTAL
This Joint 2025UWMP will be submitted to DWR within 30 days of adoption and by July 1, 2026. The adopted Joint 2025 UWMP will be submitted electronically to DWR using the Water Use Efficiency (WUE) data submittal tool. A CD of the adopted Joint 2025 UWMP will also be submitted to the California State Library.

No later than 30 days after adoption, a copy of the adopted Joint 2025 UWMP, including the WSCP, will be provided to the cities and counties to which the City and MID provides water. #20..
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10.5 PUBLIC AVAILABILITY
No later than 30 days after submittal to DWR, copies of this plan, including the City’s adopted WSCP, will be available to the public during normal business hours at the following locations:
• City of Modesto, Utilities Department, 1010 Tenth Street, 4th Floor, Modesto; and • MID Board Secretary’s Office, 1231 Eleventh Street, Modesto.

An electronic copy of the adopted Joint 2025 UWMP will also be available on the City and MID websites:
• City of Modesto Utilities Department: https://www.modestogov.com/860 • MID: https:/www.mid.org/water/reports-plans-documents/

10.6 PLAN IMPLEMENTATION
This Joint 2025 UWMP will be the source document for any SB 610 Water Supply Assessments or SB 221 Water Supply Verifications required for any proposed projects between 2026 and 2030 that are subject to the California Environmental Quality Act and would demand an amount of water equivalent or greater than the amount of water required by a 500-dwelling-unit project. Also, this Joint 2025 UWMP will provide guidance and direction on development of new local supplies and implementation of water conservation programs.

10.7 AMENDING AN ADOPTED UWMP OR WATER SHORTAGE CONTINGENCY PLAN The City and MID may amend the Joint 2025 UWMP and WSCP jointly or separately. If the City and MID amend one or both documents, the City and MID will follow the notification, public hearing, adoption, and submittal process described in Sections 10.2 through 10.4 above. In addition to submitting amendments to DWR through the WUE data portal, copies of amendments or changes to the plans will be submitted to the California State Library, as well as any city or county within which the supplier provides water, within 30 days after adoption.
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Urban Water Management Planning Act
Legislative Requirements
Appendix A
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Informational Purposes Only
January 2026 A-1
Appendix A
California Water Code—Urban Water
Management Planning
This material is for informational purposes only and is not to be used in place of official California Water Code.

This appendix presents updated sections of California Water Code (Water Code) as of the publication of this Guidebook and as compiled by California Department of Water Resources (DWR) staff. The selection here focuses on the portions of Water Code directly relevant to preparation of an Urban Water Management Plan (UWMP), and sections of Water Code that are contextually relevant to urban water suppliers and DWR.

Water Code published here also concerns the Urban Water Management Planning Act, the Water Conservation Act of 2009 (SB X7-7), which covers sustainable water use and demand reduction, and more. Further legislative information is available on the California Legislative Information website.

Contents
Water Conservation Act of 2009 (SB X7‐7) ................................................. A-3 Chapter 1. General Declarations and Policy, Sections 10608– 10608.8 .................................................................................. A-3 Chapter 2. Definitions, Section 10608.12 ............................................. A-5 Chapter 2.5. Nonfunctional Turf .......................................................... A-9 Chapter 3. Urban Retail Water Suppliers, Sections 10608.16– 10608.44............................................................................... A-11 Chapter 5. Sustainable Water Management, Section 10608.50 .............. A-21 Chapter 6. Standardized Data Collection, Section 10608.52 .................. A-22 Chapter 7. Funding Provisions, Sections 10608.56–10608.60.................. A-23 Chapter 9. Urban Water Use Objectives and Water Use Reporting, Sections 10609–10609.38 ........................................................ A-24 Urban Water Management Planning Act.................................................... A-39 Chapter 1. General Declaration and Policy, Sections 10610– 10610.4................................................................................. A-39 Chapter 2. Definitions, Sections 10611–10618 ..................................... A-40 Chapter 3. Urban Water Management Plans........................................ A-42 Article 1. General Provisions, Sections 10620–10621 ................... A-42 Article 2. Contents of Plans, Sections 10630–10634 ..................... A-44 #20..
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Article 2.5. Water Service Reliability, Section 10635 .................... A-54 Article 3. Adoption and Implementation of Plans,
Sections 10640–10645 ................................................. A-55 Chapter 4. Miscellaneous Provisions, Sections 10650–10657................. A-58 #20..
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California Water Code—Urban Water Management Planning
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Water Conservation Act of 2009 (SB X7‐7)
This section contains information extracted from Water Code Division 6, Conservation, Development, and Utilization of State Water Resources, Part 2.55, Sustainable Water Use And Demand Reduction. Click on any section header below to read Water Code directly at the California Legislative Information website.

Chapter 1. General Declarations and Policy,
Sections 10608–10608.8
Section 10608.

The Legislature finds and declares all of the following:
(a) Water is a public resource that the California Constitution protects against waste and unreasonable use.
(b) Growing population, climate change, and the need to protect and grow California’s economy while protecting and restoring our fish and wildlife habitats make it essential that the state manage its water resources as efficiently as possible.
(c) Diverse regional water supply portfolios will increase water supply reliability and reduce dependence on the Delta.
(d) Reduced water use through conservation provides significant energy and environmental benefits, and can help protect water quality, improve streamflows, and reduce greenhouse gas emissions.
(e) The success of state and local water conservation programs to increase efficiency of water use is best determined on the basis of measurable outcomes related to water use or efficiency.
(f) Improvements in technology and management practices offer the potential for increasing water efficiency in California over time, providing an essential water management tool to meet the need for water for urban, agricultural, and environmental uses.
(g) The Governor has called for a 20 percent per capita reduction in urban water use statewide by 2020.
(h) The factors used to formulate water use efficiency targets can vary significantly from location to location based on factors including weather, patterns of urban and suburban development, and past efforts to enhance water use efficiency.
(i) Per capita water use is a valid measure of a water provider’s efforts to reduce urban water use within its service area. However, per capita water use is less #20..
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Informational Purposes Only
January 2026 A-4
useful for measuring relative water use efficiency between different water providers. Differences in weather, historical patterns of urban and suburban development, and density of housing in a particular location need to be considered when assessing per capita water use as a measure of efficiency.

Section 10608.4.

It is the intent of the Legislature, by the enactment of this part, to do all of the following:
(a) Require all water suppliers to increase the efficiency of use of this essential resource.
(b) Establish a framework to meet the state targets for urban water conservation identified in this part and called for by the Governor. (c) Measure increased efficiency of urban water use on a per capita basis. (d) Establish a method or methods for urban retail water suppliers to determine targets for achieving increased water use efficiency by the year 2020, in accordance with the Governor’s goal of a 20- percent reduction. (e) Establish consistent water use efficiency planning and implementation standards for urban water suppliers and agricultural water suppliers. (f) Promote urban water conservation standards that are consistent with the California Urban Water Conservation Council’s adopted best management practices and the requirements for demand management in Section 10631. (g) Establish standards that recognize and provide credit to water suppliers that made substantial capital investments in urban water conservation since the drought of the early 1990s.
(h) Recognize and account for the investment of urban retail water suppliers in providing recycled water for beneficial uses.
(i) Require implementation of specified efficient water management practices for agricultural water suppliers.
(k) Support the economic productivity of California’s agricultural, commercial, and industrial sectors.
(l) Advance regional water resources management.

Section 10608.8.
(a)
(1) Water use efficiency measures adopted and implemented pursuant to this part or Part 2.8 (commencing with Section 10800) are water conservation measures subject to the protections provided under Section 1011. #20..
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(2) Because an urban agency is not required to meet its urban water use target until 2020 pursuant to subdivision (b) of Section 10608.24, an urban retail water supplier’s failure to meet those targets shall not establish a violation of law for purposes of any state administrative or judicial proceeding prior to January 1, 2021. Nothing in this paragraph limits the use of data reported to the department or the board in litigation or an administrative proceeding. This paragraph shall become inoperative on January 1, 2021.
(3) To the extent feasible, the department and the board shall provide for the use of water conservation reports required under this part to meet the requirements of Section 1011 for water conservation reporting. (b) This part does not limit or otherwise affect the application of Chapter 3.5 commencing with Section 11340), Chapter 4 (commencing with Section 11370), Chapter 4.5 (commencing with Section 11400), and Chapter 5 (commencing with Section 11500) of Part 1 of Division 3 of Title 2 of the Government Code.
(c) This part does not require a reduction in the total water used in the agricultural or urban sectors, because other factors, including, but not limited to, changes in agricultural economics or population growth may have greater effects on water use. This part does not limit the economic productivity of California’s agricultural, commercial, or industrial sectors.
(d) The requirements of this part do not apply to an agricultural water supplier that is a party to the Quantification Settlement Agreement, as defined in subdivision (a) of Section 1 of Chapter 617 of the Statutes of 2002, during the period within which the Quantification Settlement Agreement remains in effect.

After the expiration of the Quantification Settlement Agreement, to the extent conservation water projects implemented as part of the Quantification Settlement Agreement remain in effect, the conserved water created as part of those projects shall be credited against the obligations of the agricultural water supplier pursuant to this part.

Chapter 2. Definitions, Section 10608.12
Section 10608.12.

Unless the context otherwise requires, the following definitions govern the construction of this part:
(a) “Affordable housing” has the same meaning as defined in Section 34191.30 of the Health and Safety Code.
(b) “Agricultural water supplier” means a water supplier, either publicly or privately owned, providing water to 10,000 or more irrigated acres, excluding recycled water. “Agricultural water supplier” includes a supplier or contractor #20..
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Informational Purposes Only
January 2026 A-6
for water, regardless of the basis of right, that distributes or sells water for ultimate resale to customers. “Agricultural water supplier” does not include the department.
(c) “Base daily per capita water use” means any of the following:
(1) The urban retail water supplier’s estimate of its average gross water use, reported in gallons per capita per day and calculated over a continuous 10-year period ending no earlier than December 31, 2004, and no later than December 31, 2010.
(2) For an urban retail water supplier that meets at least 10 percent of its 2008 measured retail water demand through recycled water that is delivered within the service area of an urban retail water supplier or its urban wholesale water supplier, the urban retail water supplier may extend the
(3) calculation described in paragraph (1) up to an additional five years to a maximum of a continuous 15-year period ending no earlier than December 31, 2004, and no later than December 31, 2010. (4) For the purposes of Section 10608.22, the urban retail water supplier’s estimate of its average gross water use, reported in gallons per capita per day and calculated over a continuous five-year period ending no earlier than December 31, 2007, and no later than December 31, 2010. (d) Baseline commercial, industrial, and institutional water use” means an urban retail water supplier’s base daily per capita water use for commercial, industrial, and institutional users.
(e) “CII water use” means water used by commercial water users, industrial water users, institutional water users, and large landscape water users. (f) “Commercial water user” means a water user that provides or distributes a product or service.
(g) “Common area” means that portion of a common interest development or of a property owned or managed by a homeowners’ association or a community service organization or similar entity that is not assigned or allocated to the exclusive use of the occupants of an individual dwelling unit within the property.
(h) “Common interest development” has the same meaning as in Section 4100 of the Civil Code.
(i) “Community service organization or similar entity” has the same meaning as in Section 4110 of the Civil Code.
(j) “Community space” means an area designated by a property owner or a governmental agency to accommodate human foot traffic for civic, ceremonial, or other community events or social gatherings
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(k) Compliance daily per capita water use” means the gross water use during the final year of the reporting period, reported in gallons per capita per day. (l) “Disadvantaged community” means a community with an annual median household income that is less than 80 percent of the statewide annual median household income.
(m) “Functional turf” means a ground cover surface of turf located in a recreational use area or community space. Turf enclosed by fencing or other barriers to permanently preclude human access for recreation or assembly is not functional turf.
(n) “Gross water use” means the total volume of water, whether treated or untreated, entering the distribution system of an urban retail water supplier, excluding all of the following:
(1) Recycled water that is delivered within the service area of an urban retail water supplier or its urban wholesale water supplier.
(2) The net volume of water that the urban retail water supplier places into long-term storage.
(3) The volume of water the urban retail water supplier conveys for use by another urban water supplier.
(4) The volume of water delivered for agricultural use, except as otherwise provided in subdivision (f) of Section 10608.24.
(o) “Homeowners’ association” means an “association” as defined in Section 4080 of the Civil Code.
(p) “Industrial water user” means a water user that is primarily a manufacturer or processor of materials as defined by the North American Industry Classification System code sectors 31 to 33, inclusive, or an entity that is a water user primarily engaged in research and development.
(q) “Institutional water user” means a water user dedicated to public service. This type of user includes, among other users, higher education institutions, schools, courts, churches, hospitals, government facilities, and nonprofit research institutions.
(r) “Interim urban water use target” means the midpoint between the urban retail water supplier’s base daily per capita water use and the urban retail water supplier’s urban water use target for 2020.
(s) “Large landscape” means a nonresidential landscape as described in the performance measures for CII water use adopted pursuant to Section 10609.10.
(t) “Locally cost effective” means that the present value of the local benefits of implementing an agricultural efficiency water management practice is greater #20..
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than or equal to the present value of the local cost of implementing that measure.
(u) “Nonfunctional turf” means any turf that is not functional turf, and includes turf located within street rights-of-way and parking lots. (v) “Performance measures” means actions to be taken by urban retail water suppliers that will result in increased water use efficiency by CII water users.

Performance measures may include, but are not limited to, educating CII water users on best management practices, conducting water use audits, and preparing water management plans. Performance measures do not include process water.
(w) “Potable reuse” means direct potable reuse, indirect potable reuse for groundwater recharge, and reservoir water augmentation as those terms are defined in Section 13561.
(x) “Potable water” means water that is suitable for human consumption. (y) “Process water” means water used by industrial water users for producing a product or product content or water used for research and development.

Process water includes, but is not limited to, continuous manufacturing processes, and water used for testing, cleaning, and maintaining equipment.

Water used to cool machinery or buildings used in the manufacturing process or necessary to maintain product quality or chemical characteristics for product manufacturing or control rooms, data centers, laboratories, clean rooms, and other industrial facility units that are integral to the manufacturing or research and development process is process water. Water used in the manufacturing process that is necessary for complying with local, state, and federal health and safety laws, and is not incidental water, is process water. Process water does not mean incidental water uses.
(z) “Public water system” has the same meaning as defined in Section 116275 of the Health and Safety Code.
(aa) “Recreational use area” means an area designated by a property owner or a governmental agency to accommodate human foot traffic for recreation, including, but not limited to, sports fields, golf courses, playgrounds, picnic grounds, or pet exercise areas. This recreation may be either formal or informal.
(ab) “Recycled water” means recycled water, as defined in subdivision (n) of Section 13050.
(ac) “Regional water resources management” means sources of supply resulting from watershed-based planning for sustainable local water reliability or any of the following alternative sources of water:
(1) The capture and reuse of stormwater or rainwater.
(2) The use of recycled water.
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(3) The desalination of brackish groundwater.
(4) The conjunctive use of surface water and groundwater in a manner that is consistent with the safe yield of the groundwater basin. (ad) “Reporting period” means the years for which an urban retail water supplier reports compliance with the urban water use targets.
(ae) “Turf” has the same meaning as defined in Section 491 of Title 23 of the California Code of Regulations
(af) “Urban retail water supplier” means a water supplier, either publicly or privately owned, that directly provides potable municipal water to more than 3,000 end users or that supplies more than 3,000 acre-feet of potable water annually at retail for municipal purposes.
(ag) “Urban water supplier” has the same meaning as defined in Section 10617. (ah) “Urban water use objective” means an estimate of aggregate efficient water use for the previous year based on adopted water use efficiency standards and local service area characteristics for that year, as described in Section 10609.20.
(ai) “Urban water use target” means the urban retail water supplier’s targeted future daily per capita water use.
(aj) “Urban wholesale water supplier” means a water supplier, either publicly or privately owned, that provides more than 3,000 acre- feet of water annually at wholesale for potable municipal purposes.

Chapter 2.5. Nonfunctional Turf
Section 10608.14.
(a) The use of potable water for the irrigation of nonfunctional turf located on commercial, industrial, and institutional properties, other than a cemetery, and on properties of homeowners’ associations, common interest developments, and community service organizations or similar entities is prohibited as of the following dates:
(1) All properties owned by the Department of General Services, beginning January 1, 2027.
(2) All properties owned by local governments, local or regional public agencies, and public water systems, except those specified in paragraph (5), beginning January 1, 2027.
(3) All other institutional properties and all commercial and industrial properties, beginning January 1, 2028.
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(4) All common areas of properties of homeowners’ associations, common interest developments, and community service organizations or similar entities, beginning January 1, 2029.
(5) All properties owned by local governments, local public agencies, and public water systems in a disadvantaged community, beginning January 1, 2031, or the date upon which a state funding source is made available to fund conversion of nonfunctional turf on these properties to climateappropriate landscapes, whichever is later. (b) Notwithstanding subdivision (a), the use of potable water is not prohibited by this section to the extent necessary to ensure the health of trees and other perennial nonturf plantings, or to the extent necessary to address an immediate health and safety need.
(c) The board may, upon a showing of good cause for reasons including economic hardship, critical business need, and potential impacts to human health or safety, postpone a compliance deadline in subdivision (a) by up to three years for certain persons, institutions, and businesses, and may create a form to be used for compliance certification to the board by property owners. (d) Public water systems shall, by no later than January 1, 2027, revise their regulations, ordinances, or policies governing water service to include the requirements of subdivisions (a) and (b), as revised by the board pursuant to subdivision (c), and shall communicate the requirements to their customers on or before that date.
(e)
(1) An owner of commercial, industrial, or institutional property with more than 5,000 square feet of irrigated area other than a cemetery shall certify to the board, commencing June 30, 2030, and every three years thereafter through 2039, that their property is in compliance with the requirements of this chapter.
(2) An owner of a property with more than 5,000 square feet of irrigated common area that is a homeowners’ association, common interest development, or community service organization or similar entity shall certify to the board, commencing June 30, 2031, and every three years thereafter through 2040, that their property is in compliance with the requirements of this chapter.
(f) Noncompliance by a person or entity with this chapter or regulations adopted thereunder shall be subject to civil liability and penalties set forth in Section 1846, or to civil liability and penalties imposed by an urban retail water supplier pursuant to a locally adopted ordinance or policy. #20..
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(g)
(1) A public water system, city, county, or city and county may enforce the provisions of this chapter.
(2) To avoid duplication of enforcement, any entity identified in paragraph (1) that is not a retail public water system shall notify the retail public water system 30 days prior to enforcement of the provisions of this chapter against a property served by such system.
(3) Nothing in paragraph (2) shall preclude enforcement by any entity identified in paragraph (1) once adequate notice is given. (h) The department shall, when using funds appropriated for water conservation for turf replacement, prioritize financial assistance for nonfunctional turf replacement to public water systems serving disadvantaged communities and to owners of affordable housing.
(i) The department shall utilize the saveourwater.com internet website and outreach campaign to provide information and resources on converting nonfunctional turf to native vegetation.
(j) The Governor’s Office of Business and Economic Development shall support small and minority-owned businesses that provide services that advance compliance with this chapter.

Chapter 3. Urban Retail Water Suppliers,
Sections 10608.16–10608.44
Section 10608.16.
(a) The state shall achieve a 20-percent reduction in urban per capita water use in California on or before December 31, 2020.
(1) The state shall make incremental progress towards the state target specified in subdivision (a) by reducing urban per capita water use by at least 10 percent on or before December 31, 2015.

Section 10608.20.
(a)
(1) Each urban retail water supplier shall develop urban water use targets and an interim urban water use target by July 1, 2011. Urban retail water suppliers may elect to determine and report progress toward achieving these targets on an individual or regional basis, as provided in subdivision (a) of Section 10608.28, and may determine the targets on a fiscal year or calendar year basis.
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(2) It is the intent of the Legislature that the urban water use targets described in paragraph (1) cumulatively result in a 20-percent reduction from the baseline daily per capita water use by December 31, 2020. (b) An urban retail water supplier shall adopt one of the following methods for determining its urban water use target pursuant to subdivision (a):
(1) Eighty percent of the urban retail water supplier’s baseline per capita daily water use.
(2) The per capita daily water use that is estimated using the sum of the following performance standards:
(A) For indoor residential water use, 55 gallons per capita daily water use as a provisional standard. Upon completion of the department’s 2017 report to the Legislature pursuant to Section 10608.42, this standard may be adjusted by the Legislature by statute. (B) For landscape irrigated through dedicated or residential meters or connections, water efficiency equivalent to the standards of the Model Water Efficient Landscape Ordinance set forth in Chapter 2.7 (commencing with Section 490) of Division 2 of Title 23 of the California Code of Regulations, as in effect the later of the year of the landscape’s installation or 1992. An urban retail water supplier using the approach specified in this subparagraph shall use satellite imagery, site visits, or other best available technology to develop an accurate estimate of landscaped areas.
(C) For commercial, industrial, and institutional uses, a 10- percent reduction in water use from the baseline commercial, industrial, and institutional water use by 2020.
(3) Ninety-five percent of the applicable state hydrologic region target, as set forth in the state’s draft 20x2020 Water Conservation Plan (dated April 30, 2009). If the service area of an urban water supplier includes more than one hydrologic region, the supplier shall apportion its service area to each region based on population or area.
(4) A method that shall be identified and developed by the department, through a public process, and reported to the Legislature no later than December 31, 2010. The method developed by the department shall identify per capita targets that cumulatively result in a statewide 20- percent reduction in urban daily per capita water use by December 31, 2020. In developing urban daily per capita water use targets, the department shall do all of the following:
(A) Consider climatic differences within the state.
(B) Consider population density differences within the state. (C) Provide flexibility to communities and regions in meeting the targets. #20..
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(D) Consider different levels of per capita water use according to plant water needs in different regions.
(E) Consider different levels of commercial, industrial, and institutional water use in different regions of the state.
(F) Avoid placing an undue hardship on communities that have implemented conservation measures or taken actions to keep per capita water use low.
(c) If the department adopts a regulation pursuant to paragraph (4) of subdivision (b) that results in a requirement that an urban retail water supplier achieve a reduction in daily per capita water use that is greater than 20 percent by December 31, 2020, an urban retail water supplier that adopted the method described in paragraph (4) of subdivision (b) may limit its urban water use target to a reduction of not more than 20 percent by December 31, 2020, by adopting the method described in paragraph (1) of subdivision (b). (d) The department shall update the method described in paragraph (4) of subdivision (b) and report to the Legislature by December 31, 2014. An urban retail water supplier that adopted the method described in paragraph (4) of subdivision (b) may adopt a new urban daily per capita water use target pursuant to this updated method.
(e) An urban retail water supplier shall include in its urban water management plan due in 2010 pursuant to Part 2.6 (commencing with Section 10610) the baseline daily per capita water use, urban water use target, interim urban water use target, and compliance daily per capita water use, along with the bases for determining those estimates, including references to supporting data.
(f) When calculating per capita values for the purposes of this chapter, an urban retail water supplier shall determine population using federal, state, and local population reports and projections.
(g) An urban retail water supplier may update its 2020 urban water use target in its 2015 urban water management plan required pursuant to Part 2.6 (commencing with Section 10610).
(h)
(1) The department, through a public process and in consultation with the California Urban Water Conservation Council, shall develop technical methodologies and criteria for the consistent implementation of this part, including, but not limited to, both of the following:
(A) Methodologies for calculating base daily per capita water use, baseline commercial, industrial, and institutional water use, compliance daily per capita water use, gross water use, service area #20..
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population, indoor residential water use, and landscaped area water use.
(B) Criteria for adjustments pursuant to subdivisions (d) and (e) of Section 10608.24.
(2) The department shall post the methodologies and criteria developed pursuant to this subdivision on its internet website, and make written copies available, by October 1, 2010. An urban retail water supplier shall use the methods developed by the department in compliance with this part.
(h)
(1) The department shall adopt regulations for implementation of the provisions relating to process water in accordance with Section 10608.12, subdivision (e) of Section 10608.24, and subdivision (d) of Section 10608.26.
(2) The initial adoption of a regulation authorized by this subdivision is deemed to address an emergency, for purposes of Sections 11346.1 and 11349.6 of the Government Code, and the department is hereby exempted for that purpose from the requirements of subdivision (b) of Section 11346.1 of the Government Code. After the initial adoption of an emergency regulation pursuant to this subdivision, the department shall not request approval from the Office of Administrative Law to readopt the regulation as an emergency regulation pursuant to Section 11346.1 of the Government Code.
(j)
(1) An urban retail water supplier is granted an extension to July 1, 2011, for adoption of an urban water management plan pursuant to Part 2.6 (commencing with Section 10610) due in 2010 to allow the use of technical methodologies developed by the department pursuant to paragraph (4) of subdivision (b) and subdivision (h). An urban retail water supplier that adopts an urban water management plan due in 2010 that does not use the methodologies developed by the department pursuant to subdivision (h) shall amend the plan by July 1, 2011, to comply with this part.
(2) An urban wholesale water supplier whose urban water management plan prepared pursuant to Part 2.6 (commencing with Section 10610) was due and not submitted in 2010 is granted an extension to July 1, 2011, to permit coordination between an urban wholesale water supplier and urban retail water suppliers.
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Section 10608.22.

Notwithstanding the method adopted by an urban retail water supplier pursuant to Section 10608.20, an urban retail water supplier’s per capita daily water use reduction shall be no less than 5 percent of base daily per capita water use as defined in paragraph (3) of subdivision (c) of Section 10608.12. This section does not apply to an urban retail water supplier with a base daily per capita water use at or below 100 gallons per capita per day.

Section 10608.24.
(a) Each urban retail water supplier shall meet its interim urban water use target by December 31, 2015.
(b) Each urban retail water supplier shall meet its urban water use target by December 31, 2020.
(c) An urban retail water supplier’s compliance daily per capita water use shall be the measure of progress toward achievement of its urban water use target. (d)
(1) When determining compliance daily per capita water use, an urban retail water supplier may consider the following factors:
(A) Differences in evapotranspiration and rainfall in the baseline period compared to the compliance reporting period.
(B) Substantial changes to commercial or industrial water use resulting from increased business output and economic development that have occurred during the reporting period.
(C) Substantial changes to institutional water use resulting from fire suppression services or other extraordinary events, or from new or expanded operations, that have occurred during the reporting period. (2) If the urban retail water supplier elects to adjust its estimate of compliance daily per capita water use due to one or more of the factors described in paragraph (1), it shall provide the basis for, and data supporting, the adjustment in the report required by Section 10608.40.
(e) When developing the urban water use target pursuant to Section 10608.20, an urban retail water supplier that has a substantial percentage of industrial water use in its service area may exclude process water from the calculation of gross water use to avoid a disproportionate burden on another customer sector. (f)
(1) An urban retail water supplier that includes agricultural water use in an urban water management plan pursuant to Part 2.6 (commencing with Section 10610) may include the agricultural water use in determining #20..
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gross water use. An urban retail water supplier that includes agricultural water use in determining gross water use and develops its urban water use target pursuant to paragraph (2) of subdivision (b) of Section 10608.20 shall use a water efficient standard for agricultural irrigation of 100 percent of reference evapotranspiration multiplied by the crop coefficient for irrigated acres.
(2) An urban retail water supplier, that is also an agricultural water supplier, is not subject to the requirements of Chapter 4 (commencing with Section 10608.48), if the agricultural water use is incorporated into its urban water use target pursuant to paragraph (1).

Section 10608.26.
(a) In complying with this part, an urban retail water supplier shall conduct at least one public hearing to accomplish all of the following:
(1) Allow community input regarding the urban retail water supplier’s implementation plan for complying with this part.
(2) Consider the economic impacts of the urban retail water supplier’s implementation plan for complying with this part.
(3) Adopt a method, pursuant to subdivision (b) of Section 10608.20, for determining its urban water use target.
(b) In complying with this part, an urban retail water supplier may meet its urban water use target through efficiency improvements in any combination among its customer sectors. An urban retail water supplier shall avoid placing a disproportionate burden on any customer sector.
(c) For an urban retail water supplier that supplies water to a United States Department of Defense military installation, the urban retail water supplier’s implementation plan for complying with this part shall consider the conservation of that military installation under federal Executive Order 13514. (d)
(1) Any ordinance or resolution adopted by an urban retail water supplier after the effective date of this section shall not require existing customers as of the effective date of this section, to undertake changes in product formulation, operations, or equipment that would reduce process water use, but may provide technical assistance and financial incentives to those customers to implement efficiency measures for process water. This section shall not limit an ordinance or resolution adopted pursuant to a declaration of drought emergency by an urban retail water supplier. (2) This part shall not be construed or enforced so as to interfere with the requirements of Chapter 4 (commencing with Section 113980) to Chapter 13 (commencing with Section 114380), inclusive, of Part 7 of #20..
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Division 104 of the Health and Safety Code, or any requirement or standard for the protection of public health, public safety, or worker safety established by federal, state, or local government or recommended by recognized standard setting organizations or trade associations.

Section 10608.28.
(a) An urban retail water supplier may meet its urban water use target within its retail service area, or through mutual agreement, by any of the following:
(1) Through an urban wholesale water supplier.
(2) Through a regional agency authorized to plan and implement water conservation, including, but not limited to, an agency established under the Bay Area Water Supply and Conservation Agency Act (Division 31 (commencing with Section 81300)).
(3) Through a regional water management group as defined in Section 10537. (4) By an integrated regional water management funding area. (5) By hydrologic region.
(6) Through other appropriate geographic scales for which computation methods have been developed by the department.
(b) A regional water management group, with the written consent of its member agencies, may undertake any or all planning, reporting, and implementation functions under this chapter for the member agencies that consent to those activities. Any data or reports shall provide information both for the regional water management group and separately for each consenting urban retail water supplier and urban wholesale water supplier.

Section 10608.32.

All costs incurred pursuant to this part by a water utility regulated by the Public Utilities Commission may be recoverable in rates subject to review and approval by the Public Utilities Commission, and may be recorded in a memorandum account and reviewed for reasonableness by the Public Utilities Commission.

Section 10608.34.
(a)
(1) On or before January 1, 2017, the department shall adopt rules for all of the following:
(A) The conduct of standardized water loss audits by urban retail water suppliers in accordance with the method adopted by the American Water Works Association in the third edition of Water Audits and Loss #20..
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Control Programs, Manual M36 and in the Free Water Audit Software, version 5.0.
(B) The process for validating a water loss audit report prior to submitting the report to the department. For the purposes of this section, “validating” is a process whereby an urban retail water supplier uses a technical expert to confirm the basis of all data entries in the urban retail water supplier’s water loss audit report and to appropriately characterize the quality of the reported data. The validation process shall follow the principles and terminology laid out by the American Water Works Association in the third edition of Water Audits and Loss Control Programs, Manual M36 and in the Free Water Audit Software, version 5.0. A validated water loss audit report shall include the name and technical qualifications of the person engaged for validation.
(C) The technical qualifications required of a person to engage in validation, as described in subparagraph (B).
(D) The certification requirements for a person selected by an urban retail water supplier to provide validation of its own water loss audit report.
(E) The method of submitting a water loss audit report to the department.
(2) The department shall update rules adopted pursuant to paragraph (1) no later than six months after the release of subsequent editions of the American Water Works Association’s Water Audits and Loss Control Programs, Manual M36. Except as provided by the department, until the department adopts updated rules pursuant to this paragraph, an urban retail water supplier may rely upon a subsequent edition of the American Water Works Association’s Water Audits and Loss Control Programs, Manual M36 or the Free Water Audit Software.
(b)
(1) On or before October 1 of each year until October 1, 2023, each urban retail water supplier reporting on a calendar year basis shall submit a completed and validated water loss audit report for the previous calendar year or the previous fiscal year as prescribed by the department pursuant to subdivision (a).
(2) On or before January 1 of each year until January 1, 2024, each urban retail water supplier reporting on a fiscal year basis shall submit a completed and validated water loss audit report for the previous fiscal year as prescribed by the department pursuant to subdivision (a). (3) On or before January 1, 2024, and on or before January 1 of each year thereafter, each urban retail water supplier shall submit a completed and #20..
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validated water loss audit report for the previous calendar year or previous fiscal year as part of the report submitted to the department pursuant to subdivision (a) of Section 10609.24 and as prescribed by the department pursuant to subdivision (a).
(4) Water loss audit reports submitted on or before October 1, 2017, may be completed and validated with assistance as described in subdivision (c). (c) Using funds available for the 2016–17 fiscal year, the board shall contribute up to four hundred thousand dollars ($400,000) towards procuring water loss audit report validation assistance for urban retail water suppliers. (d) Each water loss audit report submitted to the department shall be accompanied by information, in a form specified by the department, identifying steps taken in the preceding year to increase the validity of data entered into the final audit, reduce the volume of apparent losses, and reduce the volume of real losses.
(e) At least one of the following employees of an urban retail water supplier shall attest to each water loss audit report submitted to the department:
(1) The chief financial officer.
(2) The chief engineer.
(3) The general manager.
(f) The department shall deem incomplete and return to the urban retail water supplier any final water loss audit report found by the department to be incomplete, not validated, unattested, or incongruent with known characteristics of water system operations. A water supplier shall resubmit a completed water loss audit report within 90 days of an audit being returned by the department.
(g) The department shall post all validated water loss audit reports on its internet website in a manner that allows for comparisons across water suppliers. The department shall make the validated water loss audit reports available for public viewing in a timely manner after their receipt.
(h) Using available funds, the department shall provide technical assistance to guide urban retail water suppliers’ water loss detection programs, including, but not limited to, metering techniques, pressure management techniques, condition-based assessment techniques for transmission and distribution pipelines, and utilization of portable and permanent water loss detection devices.
(i) No earlier than January 1, 2019, and no later than July 1, 2020, the board shall adopt rules requiring urban retail water suppliers to meet performance standards for the volume of water losses. In adopting these rules, the board shall employ full life-cycle cost accounting to evaluate the costs of meeting the performance standards. The board may consider establishing a minimum #20..
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allowable water loss threshold that, if reached and maintained by an urban water supplier, would exempt the urban water supplier from further water loss reduction requirements.

Section 10608.35.
(a) The department, in coordination with the board, shall conduct necessary studies and investigations and make a recommendation to the Legislature, by January 1, 2020, on the feasibility of developing and enacting water loss reporting requirements for urban wholesale water suppliers. (b) The studies and investigations shall include an evaluation of the suitability of applying the processes and requirements of Section 10608.34 to urban wholesale water suppliers.
(c) In conducting necessary studies and investigations and developing its recommendation, the department shall solicit broad public participation from stakeholders and other interested persons.

Section 10608.36.

Urban wholesale water suppliers shall include in the urban water management plans required pursuant to Part 2.6 (commencing with Section 10610) an assessment of their present and proposed future measures, programs, and policies to help achieve the water use reductions required by this part.

Section 10608.40.

Urban water retail suppliers shall report to the department on their progress in meeting their urban water use targets as part of their urban water management plans submitted pursuant to Section 10631. The data shall be reported using a standardized form developed pursuant to Section 10608.52.

Section 10608.42.
(a) The department shall review the 2015 urban water management plans and report to the Legislature by July 1, 2017, on progress towards achieving a 20- percent reduction in urban water use by December 31, 2020. The report shall include recommendations on changes to water efficiency standards or urban water use targets to achieve the 20- percent reduction and to reflect updated efficiency information and technology changes.
(b) A report to be submitted pursuant to subdivision (a) shall be submitted in compliance with Section 9795 of the Government Code.
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Section 10608.43.

The department, in conjunction with the California Urban Water Conservation Council, by April 1, 2010, shall convene a representative task force consisting of academic experts, urban retail water suppliers, environmental organizations, commercial water users, industrial water users, and institutional water users to develop alternative best management practices for commercial, industrial, and institutional users and an assessment of the potential statewide water use efficiency improvement in the commercial, industrial, and institutional sectors that would result from implementation of these best management practices. The taskforce, in conjunction with the department, shall submit a report to the Legislature by April 1, 2012, that shall include a review of multiple sectors within commercial, industrial, and institutional users and that shall recommend water use efficiency standards for commercial, industrial, and institutional users among various sectors of water use.

The report shall include, but not be limited to, the following:
(a) Appropriate metrics for evaluating commercial, industrial, and institutional water use.
(b) Evaluation of water demands for manufacturing processes, goods, and cooling. (c) Evaluation of public infrastructure necessary for delivery of recycled water to the commercial, industrial, and institutional sectors.
(d) Evaluation of institutional and economic barriers to increased recycled water use within the commercial, industrial, and institutional sectors. (e) Identification of technical feasibility and cost of the best management practices to achieve more efficient water use statewide in the commercial, industrial, and institutional sectors that is consistent with the public interest and reflects past investments in water use efficiency.

Section 10608.44.

Each state agency shall reduce water use at facilities it operates to support urban retail water suppliers in meeting the target identified in Section 10608.16.

Chapter 5. Sustainable Water Management,
Section 10608.50
Section 10608.50.
(a) The department, in consultation with the board, shall promote implementation of regional water resources management practices through increased incentives and removal of barriers consistent with state and federal law.

Potential changes may include, but are not limited to, all of the following:
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(1) Revisions to the requirements for urban and agricultural water management plans.
(2) Revisions to the requirements for integrated regional water management plans.
(3) Revisions to the eligibility for state water management grants and loans. (4) Revisions to state or local permitting requirements that increase water supply opportunities, but do not weaken water quality protection under state and federal law.
(5) Increased funding for research, feasibility studies, and project construction.
(6) Expanding technical and educational support for local land use and water management agencies.
(b) No later than January 1, 2011, and updated as part of the California Water Plan, the department, in consultation with the board, and with public input, shall propose new statewide targets, or review and update existing statewide targets, for regional water resources management practices, including, but not limited to, recycled water, brackish groundwater desalination, and infiltration and direct use of urban stormwater runoff.

Chapter 6. Standardized Data Collection,
Section 10608.52
Section 10608.52.
(a) The department, in consultation with the board, the California Bay-Delta Authority or its successor agency, the State Department of Public Health, and the Public Utilities Commission, shall develop a single standardized water use reporting form to meet the water use information needs of each agency, including the needs of urban water suppliers that elect to determine and report progress toward achieving targets on a regional basis as provided in subdivision (a) of Section 10608.28.
(b) At a minimum, the form shall be developed to accommodate information sufficient to assess an urban water supplier’s compliance with conservation targets pursuant to Section 10608.24 and an agricultural water supplier’s compliance with implementation of efficient water management practices pursuant to subdivision (a) of Section 10608.48. The form shall accommodate reporting by urban water suppliers on an individual or regional basis as provided in subdivision (a) of Section 10608.28.
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Chapter 7. Funding Provisions, Sections 10608.56–
10608.60
Section 10608.56.
(a) On and after July 1, 2016, an urban retail water supplier is not eligible for a water grant or loan awarded or administered by the state unless the supplier complies with this part.
(b) On and after July 1, 2013, an agricultural water supplier is not eligible for a water grant or loan awarded or administered by the state unless the supplier complies with this part.
(c) Notwithstanding subdivision (a), the department shall determine that an urban retail water supplier is eligible for a water grant or loan even though the supplier has not met the per capita reductions required pursuant to Section 10608.24, if the urban retail water supplier has submitted to the department for approval a schedule, financing plan, and budget, to be included in the grant or loan agreement, for achieving the per capita reductions. The supplier may request grant or loan funds to achieve the per capita reductions to the extent the request is consistent with the eligibility requirements applicable to the water funds.
(d) Notwithstanding subdivision (b), the department shall determine that an agricultural water supplier is eligible for a water grant or loan even though the supplier is not implementing all of the efficient water management practices described in Section 10608.48, if the agricultural water supplier has submitted to the department for approval a schedule, financing plan, and budget, to be included in the grant or loan agreement, for implementation of the efficient water management practices. The supplier may request grant or loan funds to implement the efficient water management practices to the extent the request is consistent with the eligibility requirements applicable to the water funds. (e) Notwithstanding subdivision (a), the department shall determine that an urban retail water supplier is eligible for a water grant or loan even though the supplier has not met the per capita reductions required pursuant to Section 10608.24, if the urban retail water supplier has submitted to the department for approval documentation demonstrating that its entire service area qualifies as a disadvantaged community.
(f) The department shall not deny eligibility to an urban retail water supplier or agricultural water supplier in compliance with the requirements of this part and Part 2.8 (commencing with Section 10800), that is participating in a multiagency water project, or an integrated regional water management plan, developed pursuant to Section 75026 of the Public Resources Code, solely on the basis that one or more of the agencies participating in the project or plan #20..
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is not implementing all of the requirements of this part or Part 2.8 (commencing with Section 10800).

Section 10608.60.
(a) It is the intent of the Legislature that funds made available by Section 75026 of the Public Resources Code should be expended, consistent with Division 43 (commencing with Section 75001) of the Public Resources Code and upon appropriation by the Legislature, for grants to implement this part. In the allocation of funding, it is the intent of the Legislature that the department give consideration to disadvantaged communities to assist in implementing the requirements of this part.
(b) It is the intent of the Legislature that funds made available by Section 75041 of the Public Resources Code, should be expended, consistent with Division 43 (commencing with Section 75001) of the Public Resources Code and upon appropriation by the Legislature, for direct expenditures to implement this part.

Chapter 9. Urban Water Use Objectives and Water Use
Reporting, Sections 10609–10609.38
Section 10609.
(a) The Legislature finds and declares that this chapter establishes a method to estimate the aggregate amount of water that would have been delivered the previous year by an urban retail water supplier if all that water had been used efficiently. This estimated aggregate water use is the urban retail water supplier’s urban water use objective. The method is based on water use efficiency standards and local service area characteristics for that year. By comparing the amount of water actually used in the previous year with the urban water use objective, local urban water suppliers will be in a better position to help eliminate unnecessary use of water; that is, water used in excess of that needed to accomplish the intended beneficial use. (b) The Legislature further finds and declares all of the following:
(1) This chapter establishes standards and practices for the following water uses:
(A) Indoor residential use.
(B) Outdoor residential use.
(C) CII water use.
(D) Water losses.
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(E) Other unique local uses and situations that can have a material effect on an urban water supplier’s total water use.
(2) This chapter further does all of the following:
(A) Establishes a method to calculate each urban water use objective. (B) Considers recycled water quality in establishing efficient irrigation standards.
(C) Requires the department to provide or otherwise identify data regarding the unique local conditions to support the calculation of an urban water use objective.
(D) Provides for the use of alternative sources of data if alternative sources are shown to be as accurate as, or more accurate than, the data provided by the department.
(E) Requires annual reporting of the previous year’s water use with the urban water use objective.
(F) Provides a bonus incentive for the amount of potable recycled water used the previous year when comparing the previous year’s water use with the urban water use objective, of up to 10 percent of the urban water use objective.
(3) This chapter requires the department and the board to solicit broad public participation from stakeholders and other interested persons in the development of the standards and the adoption of regulations pursuant to this chapter.
(4) This chapter preserves the Legislature’s authority over long- term water use efficiency target setting and ensures appropriate legislative oversight of the implementation of this chapter by doing all of the following:
(A) Requiring the Legislative Analyst to conduct a review of the implementation of this chapter, including compliance with the adopted standards and regulations, accuracy of the data, use of alternate data, and other issues the Legislative Analyst deems appropriate.
(B) Stating legislative intent that the director of the department and the chairperson of the board appear before the appropriate Senate and Assembly policy committees to report on progress in implementing this chapter.
(C) Providing one-time-only authority to the department and board to adopt water use efficiency standards, except as explicitly provided in this chapter. Authorization to update the standards shall require separate legislation.
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(c) It is the intent of the Legislature that the following principles apply to the development and implementation of long-term standards and urban water use objectives:
(1) Local urban retail water suppliers should have primary responsibility for meeting standards-based water use targets, and they shall retain the flexibility to develop their water supply portfolios, design and implement water conservation strategies, educate their customers, and enforce their rules.
(2) Long-term standards and urban water use objectives should advance the state’s goals to mitigate and adapt to climate change.
(3) Long-term standards and urban water use objectives should acknowledge the shade, air quality, and heat-island reduction benefits provided to communities by trees through the support of water-efficient irrigation practices that keep trees healthy.
(4) The state should identify opportunities for streamlined reporting, eliminate redundant data submissions, and incentivize open access to data collected by urban and agricultural water suppliers.

Section 10609.2.
(a) The board, in coordination with the department, shall adopt long-term standards for the efficient use of water pursuant to this chapter on or before June 30, 2022.
(b) Standards shall be adopted for all of the following:
(1) Outdoor residential water use.
(2) Outdoor irrigation of landscape areas with dedicated irrigation meters in connection with CII water use.
(3) A volume for water loss.
(c) When adopting the standards under this section, the board shall consider the policies of this chapter and the proposed efficiency standards’ effects on local wastewater management, developed and natural parklands, and urban tree health. The standards and potential effects shall be identified by May 30, 2022.

The board shall allow for public comment on potential effects identified by the board under this subdivision.
(d) The long-term standards shall be set at a level designed so that the water use objectives, together with other demands excluded from the long-term standards such as CII indoor water use and CII outdoor water use not connected to a dedicated landscape meter, would exceed the statewide conservation targets required pursuant to Chapter 3 (commencing with Section 10608.16).
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(e) The board, in coordination with the department, shall adopt by regulation variances recommended by the department pursuant to Section 10609.14 and guidelines and methodologies pertaining to the calculation of an urban retail water supplier’s urban water use objective recommended by the department pursuant to Section 10609.16.

Section 10609.4.
(a)
(1) Until January 1, 2025, the standard for indoor residential water use shall be 55 gallons per capita daily.
(2) Beginning January 1, 2025, and until January 1, 2030, the standard for indoor residential water use shall be 47 gallons per capita daily. (3) Beginning January 1, 2030, the standard for indoor residential water use shall be 42 gallons per capita daily.
(b)
(1) The department, in coordination with the board, shall conduct necessary studies and investigations to assess and quantify the economic benefits and impacts of the 2030 indoor residential use standard on water, wastewater, and recycled water systems and shall include saturation enduse studies. The studies and investigations shall build on the standards and potential effects identified pursuant to subdivision (c) of Section 10609.2 and shall also consider, and as appropriate incorporate, other regional and statewide studies that quantify the impacts on water, wastewater, and recycled water systems, and evaluate the long-term effects of telework. To facilitate these studies and investigations, the board may request necessary and relevant information from wastewater agencies, including monthly influent flow, actions taken to reassess treatment processes, and the impact of the implementation of this chapter on wastewater operations, maintenance, and capital investment.

The department, in coordination with the board, shall summarize the findings of these studies and investigations in a report to the Legislature on or before October 1, 2028. The report shall be submitted in compliance with Section 9795 of the Government Code.
(2) If the department, in coordination with the board, determines that the 2030 indoor residential use standard is likely to unduly impact affordability of water and wastewater services, the department and the board may jointly recommend to the Legislature an alternate date on which the 2030 indoor residential use standard shall take effect. This determination shall be made using at least two years of data reflecting application of the 2025 indoor residential use standard. #20..
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(3) Based upon the studies and investigations conducted pursuant to paragraph (1), the department shall consider whether to recommend, for adoption by the board, additional variances to accommodate unique challenges related to residential indoor water use pursuant to Section 10609.2. Variance options may include, but are not limited to, stranded assets, impacts on disadvantaged communities, impacts to environmental flows, or adverse impacts to wastewater or recycled water operations.
(4) The studies, investigations, and report described in paragraph (1) shall include timely and inclusive collaboration with, and input from, a broad group of stakeholders, including, but not limited to, environmental groups, experts in indoor plumbing, water, wastewater, and recycled water agencies.
(c) An urban retail water supplier shall not be subject to enforcement pursuant to this chapter solely for failing to meet the indoor residential use standard.

Section 10609.6.
(a)
(1) The department, in coordination with the board, shall conduct necessary studies and investigations and recommend, no later than October 1, 2021, standards for outdoor residential use for adoption by the board in accordance with this chapter.
(2)
(A) The standards shall incorporate the principles of the model water efficient landscape ordinance adopted by the department pursuant to the Water Conservation in Landscaping Act (Article 10.8 (commencing with Section 65591) of Chapter 3 of Division 1 of Title 7 of the Government Code).
(B) The standards shall apply to irrigable lands.
(C) The standards shall include provisions for swimming pools, spas, and other water features. Ornamental water features that are artificially supplied with water, including ponds, lakes, waterfalls, and fountains, shall be analyzed separately from swimming pools and spas. (b) The department shall, by January 1, 2021, provide each urban retail water supplier with data regarding the area of residential irrigable lands in a manner that can reasonably be applied to the standards adopted pursuant to this section.
(c) The department shall not recommend standards pursuant to this section until it has conducted pilot projects or studies, or some combination of the two, to ensure that the data provided to local agencies are reasonably accurate for the #20..
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data’s intended uses, taking into consideration California’s diverse landscapes and community characteristics.

Section 10609.8.
(a) The department, in coordination with the board, shall conduct necessary studies and investigations and recommend, no later than October 1, 2021, standards for outdoor irrigation of landscape areas with dedicated irrigation meters or other means of calculating outdoor irrigation use in connection with CII water use for adoption by the board in accordance with this chapter. (b) The standards shall incorporate the principles of the model water efficient landscape ordinance adopted by the department pursuant to the Water Conservation in Landscaping Act (Article 10.8 (commencing with Section 65591) of Chapter 3 of Division 1 of Title 7 of the Government Code). (c) The standards shall include an exclusion for water for commercial agricultural use meeting the definition of subdivision (b) of Section 51201 of the Government Code.

Section 10609.9.

For purposes of Sections 10609.6 and 10609.8, “principles of the model water efficient landscape ordinance” means those provisions of the model water efficient landscape ordinance applicable to the establishment or determination of the amount of water necessary to efficiently irrigate both new and existing landscapes.

These provisions include, but are not limited to, all of the following:
(a) Evapotranspiration adjustment factors, as applicable. (b) Landscape area.
(c) Maximum applied water allowance.
(d) Reference evapotranspiration.
(e) Special landscape areas, including provisions governing evapotranspiration adjustment factors for different types of water used for irrigating the landscape.

Section 10609.10.
(a) The department, in coordination with the board, shall conduct necessary studies and investigations and recommend, no later than October 1, 2021, performance measures for CII water use for adoption by the board in accordance with this chapter.
(b) Prior to recommending performance measures for CII water use, the department shall solicit broad public participation from stakeholders and other interested persons relating to all of the following:
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(1) Recommendations for a CII water use classification system for California that address significant uses of water.
(2) Recommendations for setting minimum size thresholds for converting mixed CII meters to dedicated irrigation meters, and evaluation of, and recommendations for, technologies that could be used in lieu of requiring dedicated irrigation meters.
(3) Recommendations for CII water use best management practices, which may include, but are not limited to, water audits and water management plans for those CII customers that exceed a recommended size, volume of water use, or other threshold.
(c) Recommendations of appropriate performance measures for CII water use shall be consistent with the October 21, 2013, report to the Legislature by the Commercial, Industrial, and Institutional Task Force entitled “Water Use Best Management Practices,” including the technical and financial feasibility recommendations provided in that report, and shall support the economic productivity of California’s commercial, industrial, and institutional sectors. (b)
(1) The board, in coordination with the department, shall adopt performance measures for CII water use on or before June 30, 2022.
(2) Each urban retail water supplier shall implement the performance measures adopted by the board pursuant to paragraph (1).

Section 10609.12.

The standards for water loss for urban retail water suppliers shall be the standards adopted by the board pursuant to subdivision (i) of Section 10608.34.

Section 10609.14.
(a) The department, in coordination with the board, shall conduct necessary studies and investigations and, no later than October 1, 2021, recommend for adoption by the board in accordance with this chapter appropriate variances for unique uses that can have a material effect on an urban retail water supplier’s urban water use objective.
(b) Appropriate variances may include, but are not limited to, allowances for the following:
(1) Significant use of evaporative coolers.
(2) Significant populations of horses and other livestock. (3) Significant fluctuations in seasonal populations.
(4) Significant landscaped areas irrigated with recycled water having high levels of total dissolved solids.
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(5) Significant use of water for soil compaction and dust control. (6) Significant use of water to supplement ponds and lakes to sustain wildlife. (7) Significant use of water to irrigate vegetation for fire protection. (8) Significant use of water for commercial or noncommercial agricultural use. (d) The department, in recommending variances for adoption by the board, shall also recommend a threshold of significance for each recommended variance. (e) Before including any specific variance in calculating an urban retail water supplier’s water use objective, the urban retail water supplier shall request and receive approval by the board for the inclusion of that variance. (f) The board shall post on its Internet Web site all of the following:
(1) A list of all urban retail water suppliers with approved variances. (2) The specific variance or variances approved for each urban retail water supplier.
(3) The data supporting approval of each variance.

Section 10609.15.

To help streamline water data reporting, the department and the board shall do all of the following:
(a) Identify urban water reporting requirements shared by both agencies, and post on each agency’s Internet Web site how the data is used for planning, regulatory, or other purposes.
(b) Analyze opportunities for more efficient publication of urban water reporting requirements within each agency, and analyze how each agency can integrate various data sets in a publicly accessible location, identify priority actions, and implement priority actions identified in the analysis.
(c) Make appropriate data pertaining to the urban water reporting requirements that are collected by either agency available to the public according to the principles and requirements of the Open and Transparent Water Data Act (Part 4.9 (commencing with Section 12400)).

Section 10609.16.

The department, in coordination with the board, shall conduct necessary studies and investigations and recommend, no later than October 1, 2021, guidelines and methodologies for the board to adopt that identify how an urban retail water supplier calculates its urban water use objective. The guidelines and methodologies shall address, as necessary, all of the following:
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(a) Determining the irrigable lands within the urban retail water supplier’s service area.
(b) Updating and revising methodologies described pursuant to subparagraph (A) of paragraph (1) of subdivision (h) of Section 10608.20, as appropriate, including methodologies for calculating the population in an urban retail water supplier’s service area.
(c) Using landscape area data provided by the department or alternative data. (d) Incorporating precipitation data and climate data into estimates of a urban retail water supplier’s outdoor irrigation budget for its urban water use objective.
(e) Estimating changes in outdoor landscape area and population, and calculating the urban water use objective, for years when updated landscape imagery is not available from the department.
(f) Determining acceptable levels of accuracy for the supporting data, the urban water use objective, and compliance with the urban water use objective.

Section 10609.18.

The department and the board shall solicit broad public participation from stakeholders and other interested persons in the development of the standards and the adoption of regulations pursuant to this chapter. The board shall hold at least one public meeting before taking any action on any standard or variance recommended by the department.

Section 10609.20.
(a) Each urban retail water supplier shall calculate its urban water use objective no later than January 1, 2024, and by January 1 every year thereafter. (b) The calculation shall be based on the urban retail water supplier’s water use conditions for the previous calendar or fiscal year.
(c) Each urban water supplier’s urban water use objective shall be composed of the sum of the following:
(1) Aggregate estimated efficient indoor residential water use. (2) Aggregate estimated efficient outdoor residential water use. (3) Aggregate estimated efficient outdoor irrigation of landscape areas with dedicated irrigation meters or equivalent technology in connection with CII water use.
(4) Aggregate estimated efficient water losses.
(5) Aggregate estimated water use in accordance with variances, as appropriate.
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(d)
(1) An urban retail water supplier that delivers water from a groundwater basin, reservoir, or other source that is augmented by potable reuse water may adjust its urban water use objective by a bonus incentive calculated pursuant to this subdivision.
(2) The water use objective bonus incentive shall be the volume of its potable reuse delivered to residential water users and to landscape areas with dedicated irrigation meters in connection with CII water use, on an acrefoot basis. (3) The bonus incentive pursuant to paragraph (1) shall be limited in accordance with one of the following:
(A) The bonus incentive shall not exceed 15 percent of the urban water supplier’s water use objective for any potable reuse water produced at an existing facility.
(B) The bonus incentive shall not exceed 10 percent of the urban water supplier’s water use objective for any potable reuse water produced at any facility that is not an existing facility.
(4) For purposes of this subdivision, “existing facility” means a facility that meets all of the following:
(A) The facility has a certified environmental impact report, mitigated negative declaration, or negative declaration on or before January 1, 2019.
(B) The facility begins producing and delivering potable reuse water on or before January 1, 2022.
(C) The facility uses microfiltration and reverse osmosis technologies to produce the potable reuse water.
(e)
(1) The calculation of the urban water use objective shall be made using landscape area and other data provided by the department and pursuant to the standards, guidelines, and methodologies adopted by the board.

The department shall provide data to the urban water supplier at a level of detail sufficient to allow the urban water supplier to verify its accuracy at the parcel level.
(2) Notwithstanding paragraph (1), an urban retail water supplier may use alternative data in calculating the urban water use objective if the supplier demonstrates to the department that the alternative data are equivalent, or superior, in quality and accuracy to the data provided by the department. The department may provide technical assistance to an #20..
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urban retail water supplier in evaluating whether the alternative data are appropriate for use in calculating the supplier’s urban water use objective.

Section 10609.21.
(a) For purposes of Section 10609.20, and notwithstanding paragraph (4) of subdivision (d) of Section 10609.20, “existing facility” also includes the North City Project, phase one of the Pure Water San Diego Program, for which an environmental impact report was certified on April 10, 2018. (b) This section shall become operative on January 1, 2019.

Section 10609.22.
(a) An urban retail water supplier shall calculate its actual urban water use no later than January 1, 2024, and by January 1 every year thereafter. (b) The calculation shall be based on the urban retail water supplier’s water use for the previous calendar or fiscal year.
(c) Each urban water supplier’s urban water use shall be composed of the sum of the following:
(1) Aggregate residential water use.
(2) Aggregate outdoor irrigation of landscape areas with dedicated irrigation meters in connection with CII water use.
(3) Aggregate water losses.

Section 10609.24.
(a) An urban retail water supplier shall submit a report to the department no later than January 1, 2024, and by January 1 every year thereafter. The report shall include all of the following:
(1) The urban water use objective calculated pursuant to Section 10609.20 along with relevant supporting data.
(2) The actual urban water use calculated pursuant to Section 10609.22 along with relevant supporting data.
(3) Documentation of the implementation of the performance measures for CII water use.
(4) A description of the progress made towards meeting the urban water use objective.
(5) The validated water loss audit report conducted pursuant to Section 10608.34.
(b) The department shall post the reports and information on its internet website. #20..
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(c) The board may issue an information order or conservation order to, or impose civil liability on, an entity or individual for failure to submit a report required by this section.

Section 10609.25.

As part of the first report submitted to the department by an urban retail water supplier no later than January 1, 2024, pursuant to subdivision (a) of Section 10609.24, each urban retail water supplier shall provide a narrative that describes the water demand management measures that the supplier plans to implement to achieve its urban water use objective by January 1, 2027.

Section 10609.26.
(a)
(1) On and after January 1, 2024, the board may issue informational orders pertaining to water production, water use, and water conservation to an urban retail water supplier that does not meet its urban water use objective required by this chapter. Informational orders are intended to obtain information on supplier activities, water production, and conservation efforts in order to identify technical assistance needs and assist urban water suppliers in meeting their urban water use objectives. (2) In determining whether to issue an informational order, the board shall consider the degree to which the urban retail water supplier is not meeting its urban water use objective, information provided in the report required by Section 10609.24, and actions the urban retail water supplier has implemented or will implement in order to help meet the urban water use objective.
(3) The board shall share information received pursuant to this subdivision with the department.
(4) An urban water supplier may request technical assistance from the department. The technical assistance may, to the extent available, include guidance documents, tools, and data.
(b) On and after January 1, 2025, the board may issue a written notice to an urban retail water supplier that does not meet its urban water use objective required by this chapter. The written notice may warn the urban retail water supplier that it is not meeting its urban water use objective described in Section 10609.20 and is not making adequate progress in meeting the urban water use objective, and may request that the urban retail water supplier address areas of concern in its next annual report required by Section 10609.24. In deciding whether to issue a written notice, the board may consider whether the urban retail water supplier has received an informational order, the degree to which the urban retail water supplier is not #20..
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meeting its urban water use objective, information provided in the report required by Section 10609.24, and actions the urban retail water supplier has implemented or will implement in order to help meet its urban water use objective.
(1) On and after January 1, 2026, the board may issue a conservation order to an urban retail water supplier that does not meet its urban water use objective. A conservation order may consist of, but is not limited to, referral to the department for technical assistance, requirements for education and outreach, requirements for local enforcement, and other efforts to assist urban retail water suppliers in meeting their urban water use objective.
(2) In issuing a conservation order, the board shall identify specific deficiencies in an urban retail water supplier’s progress towards meeting its urban water use objective, and identify specific actions to address the deficiencies.
(3) The board may request that the department provide an urban retail water supplier with technical assistance to support the urban retail water supplier’s actions to remedy the deficiencies.
(c) A conservation order issued in accordance with this chapter may include requiring actions intended to increase water-use efficiency, but shall not curtail or otherwise limit the exercise of a water right, nor shall it require the imposition of civil liability pursuant to Section 377.

Section 10609.27.

Notwithstanding Section 10609.26, the board shall not issue an information order, written notice, or conservation order pursuant to Section 10609.26 if both of the following conditions are met:
(a) The board determines that the urban retail water supplier is not meeting its urban water use objective solely because the volume of water loss exceeds the urban retail water supplier’s standard for water loss.
(b) Pursuant to Section 10608.34, the board is taking enforcement action against the urban retail water supplier for not meeting the performance standards for the volume of water losses.

Section 10609.28.

The board may issue a regulation or informational order requiring a wholesale water supplier, an urban retail water supplier, or a distributor of a public water supply, as that term is used in Section 350, to provide a monthly report relating to water production, water use, or water conservation.
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Section 10609.30.

On or before January 10, 2024, the Legislative Analyst shall provide to the appropriate policy committees of both houses of the Legislature and the public a report evaluating the implementation of the water use efficiency standards and water use reporting pursuant to this chapter. The board and the department shall provide the Legislative Analyst with the available data to complete this report. (a) The report shall describe all of the following:
(1) The rate at which urban retail water users are complying with the standards, and factors that might facilitate or impede their compliance. (2) The accuracy of the data and estimates being used to calculate urban water use objectives.
(3) Indications of the economic impacts, if any, of the implementation of this chapter on urban water suppliers and urban water users, including CII water users.
(4) The frequency of use of the bonus incentive, the volume of water associated with the bonus incentive, value to urban water suppliers of the bonus incentive, and any implications of the use of the bonus incentive on water use efficiency.
(5) The early indications of how implementing this chapter might impact the efficiency of statewide urban water use.
6) Recommendations, if any, for improving statewide urban water use efficiency and the standards and practices described in this chapter. (7) Any other issues the Legislative Analyst deems appropriate.

Section 10609.32.

It is the intent of the Legislature that the chairperson of the board and the director of the department appear before the appropriate policy committees of both houses of the Legislature on or around January 1, 2026, and report on the implementation of the water use efficiency standards and water use reporting pursuant to this chapter. It is the intent of the Legislature that the topics to be covered include all of the following:
(a) The rate at which urban retail water suppliers are complying with the standards, and factors that might facilitate or impede their compliance. (b) What enforcement actions have been taken, if any.
(c) The accuracy of the data and estimates being used to calculate urban water use objectives.
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(d) Indications of the economic impacts, if any, of the implementation of this chapter on urban water suppliers and urban water users, including CII water users.
(e) The frequency of use of the bonus incentive, the volume of water associated with the bonus incentive, value to urban water suppliers of the bonus incentive, and any implications of the use of the bonus incentive on water use efficiency.
(f) An assessment of how implementing this chapter is affecting the efficiency of statewide urban water use.

Section 10609.34.

Notwithstanding Section 15300.2 of Title 14 of the California Code of Regulations, an action of the board taken under this chapter shall be deemed to be a Class 8 action, within the meaning of Section 15308 of Title 14 of the California Code of Regulations, provided that the action does not involve relaxation of existing water conservation or water use standards.

Section 10609.36.
(a) Nothing in this chapter shall be construed to determine or alter water rights.

Sections 1010 and 1011 apply to water conserved through implementation of this chapter.
(b) Nothing in this chapter shall be construed to authorize the board to update or revise water use efficiency standards authorized by this chapter except as explicitly provided in this chapter. Authorization to update the standards beyond that explicitly provided in this chapter shall require separate legislation.
(c) Nothing in this chapter shall be construed to limit or otherwise affect the use of recycled water as seawater barriers for groundwater salinity management.

Section 10609.38.

The board may waive the requirements of this chapter for a period of up to five years for any urban retail water supplier whose water deliveries are significantly affected by changes in water use as a result of damage from a disaster such as an earthquake or fire. In establishing the period of a waiver, the board shall take into consideration the breadth of the damage and the time necessary for the damaged areas to recover from the disaster.
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Urban Water Management Planning Act
This section contains information extracted from Water Code Division 6, Conservation, Development, and Utilization of State Water Resources, Part 2.6, Urban Water Management Planning. Click on any section header below to read Water Code directly at the California Legislative Information website.

Chapter 1. General Declaration and Policy,
Sections 10610–10610.4
Section 10610.

This part shall be known and may be cited as the “Urban Water Management Planning Act.”
Section 10610.2.
(a) The Legislature finds and declares all of the following:
(1) The waters of the state are a limited and renewable resource subject to ever-increasing demands.
(2) The conservation and efficient use of urban water supplies are of statewide concern; however, the planning for that use and the implementation of those plans can best be accomplished at the local level. (3) A long-term, reliable supply of water is essential to protect the productivity of California’s businesses and economic climate, and increasing long-term water conservation among Californians, improving water use efficiency within the state’s communities and agricultural production, and strengthening local and regional drought planning are critical to California’s resilience to drought and climate change. (4) As part of its long-range planning activities, every urban water supplier should make every effort to ensure the appropriate level of reliability in its water service sufficient to meet the needs of its various categories of customers during normal, dry, and multiple dry water years now and into the foreseeable future, and every urban water supplier should collaborate closely with local land-use authorities to ensure water demand forecasts are consistent with current land-use planning.
(5) Public health issues have been raised over a number of contaminants that have been identified in certain local and imported water supplies. (6) Implementing effective water management strategies, including groundwater storage projects and recycled water projects, may require #20..
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specific water quality and salinity targets for meeting groundwater basins water quality objectives and promoting beneficial use of recycled water. (7) Water quality regulations are becoming an increasingly important factor in water agencies’ selection of raw water sources, treatment alternatives, and modifications to existing treatment facilities.
(8) Changes in drinking water quality standards may also impact the usefulness of water supplies and may ultimately impact supply reliability. (9) The quality of source supplies can have a significant impact on water management strategies and supply reliability.
(b) This part is intended to provide assistance to water agencies in carrying out their long-term resource planning responsibilities to ensure adequate water supplies to meet existing and future demands for water.

Section 10610.4.

The Legislature finds and declares that it is the policy of the state as follows:
(a) The management of urban water demands and efficient use of water shall be actively pursued to protect both the people of the state and their water resources.
(b) The management of urban water demands and efficient use of urban water supplies shall be a guiding criterion in public decisions. (c) Urban water suppliers shall be required to develop water management plans to achieve the efficient use of available supplies and strengthen local drought planning.

Chapter 2. Definitions, Sections 10611–10618
Section 10611.

Unless the context otherwise requires, the definitions of this chapter govern the construction of this part.

Section 10611.3.
“Customer” means a purchaser of water from a water supplier who uses the water for municipal purposes, including residential, commercial, governmental, and industrial uses.
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Section 10611.5.
“Demand management” means those water conservation measures, programs, and incentives that prevent the waste of water and promote the reasonable and efficient use and reuse of available supplies.

Section 10612.
“Drought risk assessment” means a method that examines water shortage risks based on the driest five-year historic sequence for the agency’s water supply, as described in subdivision (b) of Section 10635.

Section 10613.
“Efficient use” means those management measures that result in the most effective use of water so as to prevent its waste or unreasonable use or unreasonable method of use.

Section 10614.
“Person” means any individual, firm, association, organization, partnership, business, trust, corporation, company, public agency, or any agency of such an entity.

Section 10615.
“Plan” means an urban water management plan prepared pursuant to this part. A plan shall describe and evaluate sources of supply, reasonable and practical efficient uses, reclamation and demand management activities. The components of the plan may vary according to an individual community or area's characteristics and its capabilities to efficiently use and conserve water. The plan shall address measures for residential, commercial, governmental, and industrial water demand management as set forth in Article 2 (commencing with Section 10630) of Chapter 3. In addition, a strategy and time schedule for implementation shall be included in the plan.

Section 10616.
“Public agency” means any board, commission, county, city and county, city, regional agency, district, or other public entity.

Section 10616.5.
“Recycled water” means the reclamation and reuse of wastewater for beneficial use.
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Section 10617.
“Urban water supplier” means a supplier, either publicly or privately owned, providing water for municipal purposes either directly or indirectly to more than 3,000 customers or supplying more than 3,000 acre-feet of water annually. An urban water supplier includes a supplier or contractor for water, regardless of the basis of right, which distributes or sells for ultimate resale to customers. This part applies only to water supplied from public water systems subject to Chapter 4 (commencing with Section 116275) of Part 12 of Division 104 of the Health and Safety Code.

Section 10617.5.
“Water shortage contingency plan” means a document that incorporates the provisions detailed in subdivision (a) of Section 10632 and is subsequently adopted by an urban water supplier pursuant to this article.

Section 10618.
“Water supply and demand assessment” means a method that looks at current year and one or more dry year supplies and demands for determining water shortage risks, as described in Section 10632.1.

Chapter 3. Urban Water Management Plans
Article 1. General Provisions, Sections 10620–10621
Section 10620.
(a) Every urban water supplier shall prepare and adopt an urban water management plan in the manner set forth in Article 3 (commencing with Section 10640).
(b) Every person that becomes an urban water supplier shall adopt an urban water management plan within one year after it has become an urban water supplier.
(c) An urban water supplier indirectly providing water shall not include planning elements in its water management plan as provided in Article 2 (commencing with Section 10630) that would be applicable to urban water suppliers or public agencies directly providing water, or to their customers, without the consent of those suppliers or public agencies. (d)
(1) An urban water supplier may satisfy the requirements of this part by participation in areawide, regional, watershed, or basinwide urban water #20..
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management planning where those plans will reduce preparation costs and contribute to the achievement of conservation, efficient water use, and improved local drought resilience.
(2) Notwithstanding paragraph (1), each urban water supplier shall develop its own water shortage contingency plan, but an urban water supplier may incorporate, collaborate, and otherwise share information with other urban water suppliers or other governing entities participating in an areawide, regional, watershed, or basinwide urban water management plan, an agricultural management plan, or groundwater sustainability plan development.
(3) Each urban water supplier shall coordinate the preparation of its plan with other appropriate agencies in the area, including other water suppliers that share a common source, water management agencies, and relevant public agencies, to the extent practicable.
(e) The urban water supplier may prepare the plan with its own staff, by contract, or in cooperation with other governmental agencies.
(f) An urban water supplier shall describe in the plan water management tools and options used by that entity that will maximize resources and minimize the need to import water from other regions.

Section 10621.
(a) Each urban water supplier shall update its plan at least once every five years on or before July 1, in years ending in six and one, incorporating updated and new information from the five years preceding each update. (b) Every urban water supplier required to prepare a plan pursuant to this part shall, at least 60 days before the public hearing on the plan required by Section 10642, notify any city or county within which the supplier provides water supplies that the urban water supplier will be reviewing the plan and considering amendments or changes to the plan.

The urban water supplier may consult with, and obtain comments from, any city or county that receives notice pursuant to this subdivision. (c) An urban water supplier regulated by the Public Utilities Commission shall include its most recent plan and water shortage contingency plan as part of the supplier’s general rate case filings.
(d) The amendments to, or changes in, the plan shall be adopted and filed in the manner set forth in Article 3 (commencing with Section 10640). (e) Each urban water supplier shall update and submit its 2015 plan to the department by July 1, 2016.
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(f) Each urban water supplier shall update and submit its 2020 plan to the department by July 1, 2021.

Article 2. Contents of Plans, Sections 10630–10634
Section 10630.

It is the intention of the Legislature, in enacting this part, to permit levels of water management planning commensurate with the numbers of customers served and the volume of water supplied, while accounting for impacts from climate change.

Section 10630.5.

Each plan shall include a simple lay description of how much water the agency has on a reliable basis, how much it needs for the foreseeable future, what the agency’s strategy is for meeting its water needs, the challenges facing the agency, and any other information necessary to provide a general understanding of the agency’s plan.

Section 10631.

A plan shall be adopted in accordance with this chapter that shall do all of the following:
(a) Describe the service area of the supplier, including current and projected population, climate, and other social, economic, and demographic factors affecting the supplier’s water management planning. The projected population estimates shall be based upon data from the state, regional, or local service agency population projections within the service area of the urban water supplier and shall be in five-year increments to 20 years or as far as data is available. The description shall include the current and projected land uses within the existing or anticipated service area affecting the supplier’s water management planning. Urban water suppliers shall coordinate with local or regional land use authorities to determine the most appropriate land use information, including, where appropriate, land use information obtained from local or regional land use authorities, as developed pursuant to Article 5 (commencing with Section 65300) of Chapter 3 of Division 1 of Title 7 of the Government Code.
(b) Identify and quantify, to the extent practicable, the existing and planned sources of water available to the supplier over the same five-year increments described in subdivision (a), providing supporting and related information, including all of the following:
(1) A detailed discussion of anticipated supply availability under a normal water year, single dry year, and droughts lasting at least five years, as well as more frequent and severe periods of drought, as described in the #20..
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drought risk assessment. For each source of water supply, consider any information pertinent to the reliability analysis conducted pursuant to Section 10635, including changes in supply due to climate change. (2) When multiple sources of water supply are identified, a description of the management of each supply in correlation with the other identified supplies.
(3) For any planned sources of water supply, a description of the measures that are being undertaken to acquire and develop those water supplies. (4) If groundwater is identified as an existing or planned source of water available to the supplier, all of the following information:
(A) The current version of any groundwater sustainability plan or alternative adopted pursuant to Part 2.74 (commencing with Section 10720), any groundwater management plan adopted by the urban water supplier, including plans adopted pursuant to Part 2.75 (commencing with Section 10750), or any other specific
authorization for groundwater management for basins underlying the urban water supplier’s service area.
(B) A description of any groundwater basin or basins from which the urban water supplier pumps groundwater.
(C) For basins that a court or the board has adjudicated the rights to pump groundwater, a copy of the order or decree adopted by the court or the board and a description of the amount of groundwater the urban water supplier has the legal right to pump under the order or decree. For a basin that has not been adjudicated, information as to whether the department has identified the basin as a high- or medium-priority basin in the most current official departmental bulletin that characterizes the condition of the groundwater basin, and a detailed description of the efforts being undertaken by the urban water supplier to coordinate with groundwater sustainability agencies or groundwater management agencies listed in subdivision (c) of Section 10723 to maintain or achieve sustainable groundwater conditions in accordance with a groundwater sustainability plan or alternative adopted pursuant to Part 2.74 (commencing with Section 10720).
(D) A detailed description and analysis of the location, amount, and sufficiency of groundwater pumped by the urban water supplier for the past five years. The description and analysis shall be based on information that is reasonably available, including, but not limited to, historic use records.
(E) A detailed description and analysis of the amount and location of groundwater that is projected to be pumped by the urban water #20..
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supplier. The description and analysis shall be based on information that is reasonably available, including, but not limited to, historic use records.
(c) Describe the opportunities for exchanges or transfers of water on a short-term or long-term basis.
(d)
(1) For an urban retail water supplier, quantify, to the extent records are available, past and current water use, over the same five-year increments described in subdivision (a), and projected water use, based upon information developed pursuant to subdivision (a), identifying the uses among water use sectors, including, but not necessarily limited to, all of the following:
(A) Single-family residential.
(B) Multifamily.
(C) Commercial.
(D) Industrial.
(E) Institutional and governmental.
(F) Landscape.
(G) Sales to other agencies.
(H) Saline water intrusion barriers, groundwater recharge, or conjunctive use, or any combination thereof.
(I) Agricultural.
(J) Distribution system water loss.
(2) The water use projections shall be in the same five-year increments described in subdivision (a).
(3)
(A) The distribution system water loss shall be quantified for each of the five years preceding the plan update, in accordance with rules adopted pursuant to Section 10608.34.
(B) The distribution system water loss quantification shall be reported in accordance with a worksheet approved or developed by the department through a public process. The water loss quantification worksheet shall be based on the water system balance methodology developed by the American Water Works Association.
(C) In the plan due July 1, 2021, and in each update thereafter, data shall be included to show whether the urban retail water supplier met #20..
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the distribution loss standards enacted by the board pursuant to Section 10608.34.
(4)
(A) Water use projections, where available, shall display and account for the water savings estimated to result from adopted codes, standards, ordinances, or transportation and land use plans identified by the urban water supplier, as applicable to the service area. (B) To the extent that an urban water supplier reports the information described in subparagraph (A), an urban water supplier shall do both of the following:
(i) Provide citations of the various codes, standards, ordinances, or transportation and land use plans utilized in making the projections.
(ii) Indicate the extent that the water use projections consider savings from codes, standards, ordinances, or transportation and land use plans. Water use projections that do not account for these water savings shall be noted of that fact.
(a) Provide a description of the supplier’s water demand management measures.

This description shall include all of the following:
(1)
(A) For an urban retail water supplier, as defined in Section 10608.12, a narrative description that addresses the nature and extent of each water demand management measure implemented over the past five years. The narrative shall describe the water demand management measures that the supplier plans to implement to achieve its water use targets pursuant to Section 10608.20.
(B) The narrative pursuant to this paragraph shall include descriptions of the following water demand management measures:
(i) Water waste prevention ordinances.
(ii) Metering.
(iii) Conservation pricing.
(iv) Public education and outreach.
(v) Programs to assess and manage distribution system real loss. (vi) Water conservation program coordination and staffing support. (vii) Other demand management measures that have a significant impact on water use as measured in gallons per capita per day, including innovative measures, if implemented.
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(2) For an urban wholesale water supplier, as defined in Section 10608.12, a narrative description of the items in clauses (ii), (iv), (vi), and (vii) of subparagraph (B) of paragraph (1), and a narrative description of its distribution system asset management and wholesale supplier assistance programs.
(f) Include a description of all water supply projects and water supply programs that may be undertaken by the urban water supplier to meet the total projected water use, as established pursuant to subdivision (a) of Section 10635. The urban water supplier shall include a detailed description of expected future projects and programs that the urban water supplier may implement to increase the amount of the water supply available to the urban water supplier in normal and single-dry water years and for a period of drought lasting five consecutive water years. The description shall identify specific projects and include a description of the increase in water supply that is expected to be available from each project. The description shall include an estimate with regard to the implementation timeline for each project or program.
(g) Describe the opportunities for development of desalinated water, including, but not limited to, ocean water, brackish water, and groundwater, as a long-term supply.
(h) An urban water supplier that relies upon a wholesale agency for a source of water shall provide the wholesale agency with water use projections from that agency for that source of water in five-year increments to 20 years or as far as data is available. The wholesale agency shall provide information to the urban water supplier for inclusion in the urban water supplier’s plan that identifies and quantifies, to the extent practicable, the existing and planned sources of water as required by subdivision (b), available from the wholesale agency to the urban water supplier over the same five- year increments, and during various water-year types in accordance with subdivision (f). An urban water supplier may rely upon water supply information provided by the wholesale agency in fulfilling the plan informational requirements of subdivisions (b) and (f).

Section 10631.1.
(a) The water use projections required by Section 10631 shall include projected water use for single-family and multifamily residential housing needed for lower income households, as defined in Section 50079.5 of the Health and Safety Code, as identified in the housing element of any city, county, or city and county in the service area of the supplier.
(b) It is the intent of the Legislature that the identification of projected water use for single-family and multifamily residential housing for lower income households will assist a supplier in complying with the requirement under #20..
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Section 65589.7 of the Government Code to grant a priority for the provision of service to housing units affordable to lower income households.

Section 10631.2.
(a) In addition to the requirements of Section 10631, an urban water management plan shall include any of the following information that the urban water supplier can readily obtain:
(1) An estimate of the amount of energy used to extract or divert water supplies.
(2) An estimate of the amount of energy used to convey water supplies to the water treatment plants or distribution systems.
(3) An estimate of the amount of energy used to treat water supplies. (4) An estimate of the amount of energy used to distribute water supplies through its distribution systems.
(5) An estimate of the amount of energy used for treated water supplies in comparison to the amount used for nontreated water supplies. (6) An estimate of the amount of energy used to place water into or withdraw from storage.
(7) Any other energy-related information the urban water supplier deems appropriate.
(b) The department shall include in its guidance for the preparation of urban water management plans a methodology for the voluntary calculation or estimation of the energy intensity of urban water systems. The department may consider studies and calculations conducted by the Public Utilities Commission in developing the methodology.
(c) The Legislature finds and declares that energy use is only one factor in water supply planning and shall not be considered independently of other factors.

Section 10632.
(a) Every urban water supplier shall prepare and adopt a water shortage contingency plan as part of its urban water management plan that consists of each of the following elements:
(1) The analysis of water supply reliability conducted pursuant to Section 10635.
(2) The procedures used in conducting an annual water supply and demand assessment that include, at a minimum, both of the following:
(A) The written decision making process that an urban water supplier will use each year to determine its water supply reliability. #20..
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(B) The key data inputs and assessment methodology used to evaluate the urban water supplier’s water supply reliability for the current year and one dry year, including all of the following:
(i) Current year unconstrained demand, considering weather, growth, and other influencing factors, such as policies to manage current supplies to meet demand objectives in future years, as applicable.
(ii) Current year available supply, considering hydrological and regulatory conditions in the current year and one dry year. The annual supply and demand assessment may consider more than one dry year solely at the discretion of the urban water supplier. (iii) Existing infrastructure capabilities and plausible constraints. (iv) A defined set of locally applicable evaluation criteria that are consistently relied upon for each annual water supply and demand assessment.
(v) A description and quantification of each source of water supply. (3)
(A) Six standard water shortage levels corresponding to progressive ranges of up to 10, 20, 30, 40, and 50 percent shortages and greater than 50 percent shortage. Urban water suppliers shall define these shortage levels based on the suppliers’ water supply conditions, including percentage reductions in water supply, changes in groundwater levels, changes in surface elevation or level of subsidence, or other changes in hydrological or other local conditions indicative of the water supply available for use. Shortage levels shall also apply to catastrophic interruption of water supplies, including, but not limited to, a regional power outage, an earthquake, and other potential emergency events.
(B) An urban water supplier with an existing water shortage contingency plan that uses different water shortage levels may comply with the requirement in subparagraph (A) by developing and including a cross- reference relating its existing categories to the six standard water shortage levels.
(4) Shortage response actions that align with the defined shortage levels and include, at a minimum, all of the following:
(A) Locally appropriate supply augmentation actions.
(B) Locally appropriate demand reduction actions to adequately respond to shortages.
(C) Locally appropriate operational changes.
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(D) Additional, mandatory prohibitions against specific water use practices that are in addition to state- mandated prohibitions and appropriate to the local conditions.
(E) For each action, an estimate of the extent to which the gap between supplies and demand will be reduced by implementation of the action.
(5) Communication protocols and procedures to inform customers, the public, interested parties, and local, regional, and state governments, regarding, at a minimum, all of the following:
(A) Any current or predicted shortages as determined by the annual water supply and demand assessment described pursuant to Section 10632.1.
(B) Any shortage response actions triggered or anticipated to be triggered by the annual water supply and demand assessment described pursuant to Section 10632.1.
(C) Any other relevant communications.
(6) For an urban retail water supplier, customer compliance, enforcement, appeal, and exemption procedures for triggered shortage response actions as determined pursuant to Section 10632.2.
(7)
(A) A description of the legal authorities that empower the urban water supplier to implement and enforce its shortage response actions specified in paragraph (4) that may include, but are not limited to, statutory authorities, ordinances, resolutions, and contract provisions.
(B) A statement that an urban water supplier shall declare a water shortage emergency in accordance with Chapter 3 (commencing with Section 350) of Division 1.
(C) A statement that an urban water supplier shall coordinate with any city or county within which it provides water supply services for the possible proclamation of a local emergency, as defined in Section 8558 of the Government Code.
(8) A description of the financial consequences of, and responses for, drought conditions, including, but not limited to, all of the following:
(A) A description of potential revenue reductions and expense increases associated with activated shortage response actions described in paragraph (4).
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(B) A description of mitigation actions needed to address revenue reductions and expense increases associated with activated shortage response actions described in paragraph (4).
(C) A description of the cost of compliance with Chapter 3.3 (commencing with Section 365) of Division 1.
(9) For an urban retail water supplier, monitoring and reporting requirements and procedures that ensure appropriate data is collected, tracked, and analyzed for purposes of monitoring customer compliance and to meet state reporting requirements.
(10) Reevaluation and improvement procedures for systematically monitoring and evaluating the functionality of the water shortage contingency plan in order to ensure shortage risk tolerance is adequate and appropriate water shortage mitigation strategies are implemented as needed. (b) For purposes of developing the water shortage contingency plan pursuant to subdivision (a), an urban water supplier shall analyze and define water features that are artificially supplied with water, including ponds, lakes, waterfalls, and fountains, separately from swimming pools and spas, as defined in subdivision (a) of Section 115921 of the Health and Safety Code. (c) The urban water supplier shall make available the water shortage contingency plan prepared pursuant to this article to its customers and any city or county within which it provides water supplies no later than 30 days after adoption of the water shortage contingency plan.

Section 10632.1.

An urban water supplier shall conduct an annual water supply and demand assessment pursuant to subdivision (a) of Section 10632 and, on or before July 1 of each year, submit an annual water shortage assessment report to the department with information for anticipated shortage, triggered shortage response actions, compliance and enforcement actions, and communication actions consistent with the supplier’s water shortage contingency plan. An urban water supplier that relies on imported water from the State Water Project or the Bureau of Reclamation shall submit its annual water supply and demand assessment within 14 days of receiving its final allocations, or by July 1 of each year, whichever is later.

Section 10632.2.

An urban water supplier shall follow, where feasible and appropriate, the prescribed procedures and implement determined shortage response actions in its water shortage contingency plan, as identified in subdivision (a) of Section 10632, or reasonable alternative actions, provided that descriptions of the alternative actions are submitted with the annual water shortage assessment report pursuant to Section 10632.1. Nothing in this section prohibits an urban water supplier from #20..
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taking actions not specified in its water shortage contingency plan, if needed, without having to formally amend its urban water management plan or water shortage contingency plan.

Section 10632.3.

It is the intent of the Legislature that, upon proclamation by the Governor of a state of emergency under the California Emergency Services Act (Chapter 7 (commencing with Section 8550) of Division 1 of Title 2 of the Government Code) based on drought conditions, the board defer to implementation of locally adopted water shortage contingency plans to the extent practicable.

Section 10632.5.
(a) In addition to the requirements of paragraph (3) of subdivision of Section 10632, beginning January 1, 2020, the plan shall include a seismic risk assessment and mitigation plan to assess the vulnerability of each of the various facilities of a water system and mitigate those vulnerabilities. (b) An urban water supplier shall update the seismic risk assessment and mitigation plan when updating its urban water management plan as required by Section 10621.
(c) An urban water supplier may comply with this section by submitting, pursuant to Section 10644, a copy of the most recent adopted local hazard mitigation plan or multihazard mitigation plan under the federal Disaster Mitigation Act of 2000 (Public Law 106- 390) if the local hazard mitigation plan or multihazard mitigation plan addresses seismic risk.

Section 10633.

The plan shall provide, to the extent available, information on recycled water and its potential for use as a water source in the service area of the urban water supplier. The preparation of the plan shall be coordinated with local water, wastewater, groundwater, and planning agencies that operate within the supplier’s service area, and shall include all of the following:
(a) A description of the wastewater collection and treatment systems in the supplier’s service area, including a quantification of the amount of wastewater collected and treated and the methods of wastewater disposal. (b) A description of the quantity of treated wastewater that meets recycled water standards, is being discharged, and is otherwise available for use in a recycled water project.
(c) A description of the recycled water currently being used in the supplier’s service area, including, but not limited to, the type, place, and quantity of use. #20..
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(d) A description and quantification of the potential uses of recycled water, including, but not limited to, agricultural irrigation, landscape irrigation, wildlife habitat enhancement, wetlands, industrial reuse, groundwater recharge, indirect potable reuse, and other appropriate uses, and a determination with regard to the technical and economic feasibility of serving those uses. (e) The projected use of recycled water within the supplier’s service area at the end of 5, 10, 15, and 20 years, and a description of the actual use of recycled water in comparison to uses previously projected pursuant to this subdivision. (f) A description of actions, including financial incentives, which may be taken to encourage the use of recycled water, and the projected results of these actions in terms of acre-feet of recycled water used per year.
(g) A plan for optimizing the use of recycled water in the supplier’s service area, including actions to facilitate the installation of dual distribution systems, to promote recirculating uses, to facilitate the increased use of treated wastewater that meets recycled water standards, and to overcome any obstacles to achieving that increased use.

Section 10634.

The plan shall include information, to the extent practicable, relating to the quality of existing sources of water available to the supplier over the same five-year increments as described in subdivision (a) of Section 10631, and the manner in which water quality affects water management strategies and supply reliability.

Article 2.5. Water Service Reliability, Section 10635
Section 10635.
(a) Every urban water supplier shall include, as part of its urban water management plan, an assessment of the reliability of its water service to its customers during normal, dry, and multiple dry water years. This water supply and demand assessment shall compare the total water supply sources available to the water supplier with the long-term total projected water use over the next 20 years, in five-year increments, for a normal water year, a single dry water year, and a drought lasting five consecutive water years. The water service reliability assessment shall be based upon the information compiled pursuant to Section 10631, including available data from state, regional, or local agency population projections within the service area of the urban water supplier.
(b) Every urban water supplier shall include, as part of its urban water management plan, a drought risk assessment for its water service to its customers as part of information considered in developing the demand management measures and water supply projects and programs to be included #20..
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January 2026 A-55
in the urban water management plan. The urban water supplier may conduct an interim update or updates to this drought risk assessment within the fiveyear cycle of its urban water management plan update. The drought risk assessment shall include each of the following:
(1) A description of the data, methodology, and basis for one or more supply shortage conditions that are necessary to conduct a drought risk assessment for a drought period that lasts five consecutive water years, starting from the year following when the assessment is conducted. (2) A determination of the reliability of each source of supply under a variety of water shortage conditions. This may include a determination that a particular source of water supply is fully reliable under most, if not all, conditions.
(3) A comparison of the total water supply sources available to the water supplier with the total projected water use for the drought period. (4) Considerations of the historical drought hydrology, plausible changes on projected supplies and demands under climate change conditions, anticipated regulatory changes, and other locally applicable criteria. (c) The urban water supplier shall provide that portion of its urban water management plan prepared pursuant to this article to any city or county within which it provides water supplies no later than 60 days after the submission of its urban water management plan.
(d) Nothing in this article is intended to create a right or entitlement to water service or any specific level of water service.
(e) Nothing in this article is intended to change existing law concerning an urban water supplier’s obligation to provide water service to its existing customers or to any potential future customers.

Article 3. Adoption and Implementation of Plans,
Sections 10640–10645
Section 10640.
(a) Every urban water supplier required to prepare a plan pursuant to this part shall prepare its plan pursuant to Article 2 (commencing with Section 10630).

The supplier shall likewise periodically review the plan as required by Section 10621, and any amendments or changes required as a result of that review shall be adopted pursuant to this article.
(b) Every urban water supplier required to prepare a water shortage contingency plan shall prepare a water shortage contingency plan pursuant to Section 10632. The supplier shall likewise periodically review the water shortage contingency plan as required by paragraph (10) of subdivision (a) of #20..
- 942 -
Appendix A
California Water Code—Urban Water Management Planning
Informational Purposes Only
January 2026 A-56
Section 10632 and any amendments or changes required as a result of that review shall be adopted pursuant to this article.

Section 10641.

An urban water supplier required to prepare a plan or a water shortage contingency plan may consult with, and obtain comments from, any public agency or state agency or any person who has special expertise with respect to water demand management methods and techniques.

Section 10642.

Each urban water supplier shall encourage the active involvement of diverse social, cultural, and economic elements of the population within the service area prior to and during the preparation of both the plan and the water shortage contingency plan. Prior to adopting either, the urban water supplier shall make both the plan and the water shortage contingency plan available for public inspection and shall hold a public hearing or hearings thereon. Prior to any of these hearings, notice of the time and place of the hearing shall be published within the jurisdiction of the publicly owned water supplier pursuant to Section 6066 of the Government Code.

The urban water supplier shall provide notice of the time and place of a hearing to any city or county within which the supplier provides water supplies. Notices by a local public agency pursuant to this section shall be provided pursuant to Chapter 17.5 (commencing with Section 7290) of Division 7 of Title 1 of the Government Code. A privately owned water supplier shall provide an equivalent notice within its service area. After the hearing or hearings, the plan or water shortage contingency plan shall be adopted as prepared or as modified after the hearing or hearings.

Section 10643.

An urban water supplier shall implement its plan adopted pursuant to this chapter in accordance with the schedule set forth in its plan.

Section 10644.
(a)
(1) An urban water supplier shall submit to the department, the California State Library, and any city or county within which the supplier provides water supplies a copy of its plan no later than 30 days after adoption.

Copies of amendments or changes to the plans shall be submitted to the department, the California State Library, and any city or county within which the supplier provides water supplies within 30 days after adoption. (2) The plan, or amendments to the plan, submitted to the department pursuant to paragraph (1) shall be submitted electronically and shall #20..
- 943 -
Appendix A
California Water Code—Urban Water Management Planning
Informational Purposes Only
January 2026 A-57
include any standardized forms, tables, or displays specified by the department.
(b) If an urban water supplier revises its water shortage contingency plan, the supplier shall submit to the department a copy of its water shortage contingency plan prepared pursuant to subdivision (a) of Section 10632 no later than 30 days after adoption, in accordance with protocols for submission and using electronic reporting tools developed by the department. (c)
(1)
(A) Notwithstanding Section 10231.5 of the Government Code, the department shall prepare and submit to the Legislature, on or before July 1, in the years ending in seven and two, a report summarizing the status of the plans and water shortage contingency plans adopted pursuant to this part. The report prepared by the department shall identify the exemplary elements of the individual plans and water shortage contingency plans. The department shall provide a copy of the report to each urban water supplier that has submitted its plan and water shortage contingency plan to the department. The department shall also prepare reports and provide data for any legislative hearings designed to consider the effectiveness of plans and water shortage contingency plans submitted pursuant to this part.
(B) The department shall prepare and submit to the board, on or before September 30 of each year, a report summarizing the submitted water supply and demand assessment results along with appropriate reported water shortage conditions and the regional and statewide analysis of water supply conditions developed by the department. As part of the report, the department shall provide a summary and, as appropriate, urban water supplier specific information regarding various shortage response actions implemented as a result of annual supplier-specific water supply and demand assessments performed pursuant to Section 10632.1.
(C) The department shall submit the report to the Legislature for the 2015 plans by July 1, 2017, and the report to the Legislature for the 2020 plans and water shortage contingency plans by July 1, 2022. (2) A report to be submitted pursuant to subparagraph (A) of paragraph (1) shall be submitted in compliance with Section 9795 of the Government Code.
(d) The department shall make available to the public the standard the department will use to identify exemplary water demand management measures. #20..
- 944 -
Appendix A
California Water Code—Urban Water Management Planning
Informational Purposes Only
January 2026 A-58
Section 10645.
(a) Not later than 30 days after filing a copy of its plan with the department, the urban water supplier and the department shall make the plan available for public review during normal business hours.
(b) Not later than 30 days after filing a copy of its water shortage contingency plan with the department, the urban water supplier and the department shall make the plan available for public review during normal business hours.

Chapter 4. Miscellaneous Provisions, Sections 10650–
10657
Section 10650.

Any actions or proceedings, other than actions by the board, to attack, review, set aside, void, or annul the acts or decisions of an urban water supplier on the grounds of noncompliance with this part shall be commenced as follows:
(a) An action or proceeding alleging failure to adopt a plan or a water shortage contingency plan shall be commenced within 18 months after that adoption is required by this part.
(b) Any action or proceeding alleging that a plan or water shortage contingency plan, or action taken pursuant to either, does not comply with this part shall be commenced within 90 days after filing of the plan or water shortage contingency plan or an amendment to either pursuant to Section 10644 or the taking of that action.

Section 10651.

In any action or proceeding to attack, review, set aside, void, or annul a plan or a water shortage contingency plan, or an action taken pursuant to either by an urban water supplier on the grounds of noncompliance with this part, the inquiry shall extend only to whether there was a prejudicial abuse of discretion. Abuse of discretion is established if the supplier has not proceeded in a manner required by law or if the action by the water supplier is not supported by substantial evidence.

Section 10652.

The California Environmental Quality Act (Division 13 (commencing with Section 21000) of the Public Resources Code) does not apply to the preparation and adoption of plans pursuant to this part or to the implementation of actions taken pursuant to Section 10632. Nothing in this part shall be interpreted as exempting from the California Environmental Quality Act any project that would significantly affect water supplies for fish and wildlife, or any project for implementation of the #20..
- 945 -
Appendix A
California Water Code—Urban Water Management Planning
Informational Purposes Only
January 2026 A-59
plan, other than projects implementing Section 10632, or any project for expanded or additional water supplies.

Section 10653.

The adoption of a plan shall satisfy any requirements of state law, regulation, or order, including those of the board and the Public Utilities Commission, for the preparation of water management plans, water shortage contingency plans, or conservation plans; provided, that if the board or the Public Utilities Commission requires additional information concerning water conservation, drought response measures, or financial conditions to implement its existing authority, nothing in this part shall be deemed to limit the board or the commission in obtaining that information. The requirements of this part shall be satisfied by any urban water demand management plan that complies with analogous federal laws or regulations after the effective date of this part, and which substantially meets the requirements of this part, or by any existing urban water management plan which includes the contents of a plan required under this part.

Section 10654.

An urban water supplier may recover in its rates the costs incurred in preparing its urban water management plan, its drought risk assessment, its water supply and demand assessment, and its water shortage contingency plan and implementing the reasonable water conservation measures included in either of the plans.

Section 10655.

If any provision of this part or the application thereof to any person or circumstances is held invalid, that invalidity shall not affect other provisions or applications of this part which can be given effect without the invalid provision or application thereof, and to this end the provisions of this part are severable.

Section 10656.

An urban water supplier is not eligible for a water grant or loan awarded or administered by the state unless the urban water supplier complies with this part.

Section 10657.

The department may adopt regulations regarding the definitions of water, water use, and reporting periods, and may adopt any other regulations deemed necessary or desirable to implement this part. In developing regulations pursuant to this section, the department shall solicit broad public participation from stakeholders and other interested persons.
#20..
- 946 -
DWR 2025 Urban Water Management Plan Tables
Appendix B
#20..
- 947 -
CA5010010(a) City of Modesto 70,755 47,558
CA5010005 Salida 4,417 1,068
CA5010031(b) Ceres (Walnut Manor) 53 35
CA5010033 Grayson 278 127
CA5010029 Del Rio (Hillcrest) 407 759
CA5010034 North Turlock 52 25
CA5010023 South Turlock 335 166
CA5010035(c) Central Turlock 36 0
76,333 49,738
Submittal Table 2-1 Retail: Public Water Systems
NOTES:
(a) The City of Modesto main PWS includes the contiguous unincorporated areas of the County such as Empire and parts of the City of Ceres (North Ceres).
(b) The Ceres Walnut Manor system is also known as "Payne" for the street where the well is located. (c) The Central Turlock water system is owned and managed by the City of Modesto, but is supplied water by the City of Turlock distribution system via an interconnection. Per the City of Turlock, approximately 5 MG of water was supplied to this system in 2025.

Volume of Water
Supplied 2025 (AF)
DWR NOTES:

Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-

3. This table identifies the unit of measure selected in Submittal Table 2-3.

Total
Public Water System
Number Public Water System Name Number of Municipal
Connections 2025
Select
One
Name of Regional Alliance or
RUWMP (Drop Down List)
NOTES:

Submittal Table 2-2: Plan Identification
Type of Plan
Individual UWMP
If Water Supplier is also a member of a SB X7-7 Regional Alliance, select name from the drop-down.

Regional Urban Water Management Plan (RUWMP)
If Supplier selected RUWMP, select name from the dropdown. #20..
- 948 -
Supplier is a wholesale supplier
Supplier is a retail supplier
UWMP Tables are in calendar years
UWMP Tables are in fiscal years
Unit AF
Submittal Table 2-3: Supplier Identification
Type of Supplier (select one or both)
Fiscal or Calendar Year (select one)
If using fiscal years provide month and date that the fiscal year begins (mm/dd)
Units of measure used in UWMP
(Select from the drop down list).

DWR NOTES:

Units of measure (AF, CCF, MG) must remain consistent
throughout the UWMP as reported in Submittal Table 2-3.

NOTES:

Submittal Table 2-4 Retail: Water Supplier Information Exchange Water Code Section 10631(h)
The retail Supplier has informed the following wholesale supplier(s) of projected water use.

Wholesale Water Supplier Name
Modesto Irrigation District (MID)
NOTES:
#20..
- 949 -
Check the box if the Supplier has informed more than 10 other water suppliers of water supplies available.

Completion of the table below is optional. If not completed, include a list of the water suppliers that were informed.

Provide page number for location of the list.

Check the box if the Supplier has informed 10 or fewer other water suppliers of water supplies available.

Complete the table below.

NOTES:

Submittal Table 2-4 Wholesale: Water Supplier Information Exchange Water Code Section 10631(h)
Water Supplier Name
City of Modesto
2025 2030 2035 2040 2045 2050(opt)
270,450 282,120 293,410 305,100 317,200 328,490
Submittal Table 3-1 Retail: Population - Current and Projected Water Code Section 10631(a)
Population
Served
NOTES: The current and projected population includes the City of Modesto incorporated area and other outlying water service areas outside of Modesto city limits.
2025 2030 2035 2040 2045 2050(opt)
0 0 0 0 0 0
Submittal Table 3-1 Wholesale: Population - Current and Projected Water Code Section 10631(a)
Population
Served
NOTES: MID does not directly serve any urban water customers. The population served by MID wholesale water is included in the City's total service area population (see DWR Table 3-1 Retail).
#20..
- 950 -
Use Type
Drop down list
May select each use multiple times
These are the only use types that will be
recognized by the WUEdata online
submittal tool
Potable or NonPotable
(OPTIONAL)
Drop down list
Volume (AF)
Single Family Potable 24,361
Multi-Family Potable 5,837
Commercial Potable 9,041
Industrial Potable 2,855
Institutional/Governmental Includes schools and churches. Potable 2,328 Landscape Potable 2,651
Losses See note (b). Potable 2,666
Landscape Raw water irrigation wells. See
note (c). Non-Potable 1,865
49,738
1,865
Total 51,603
Submittal Table 4-1 Retail: Total Uses for Potable and Non-Potable Water — Actual Water Code Section 10631(d)(1)
NOTES:
(a) Water use is based on metered water consumption and includes water use by all public water systems listed in Table 2-1 (DWR Table 2-1 Retail).
(b) Losses are calculated as the difference between total production (including groundwater and purchased surface water) and metered consumption.
(c) Raw water irrigation wells are not metered. Annual use is estimated based on the irrigable area of individual parks served.

DWR NOTES: Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3. This table identifies the unit of measure selected in Submittal Table 2- 2025 Actual Water Use
Subtotal Potable
Subtotal Non-Potable
Additional Description
(as needed) Use Type
Drop down list
May select each use multiple times
These are the only use types that will be
recognized by the WUEdata online submittal
tool
Potable or Non-Potable
(OPTIONAL)
Drop down list
Volume (AF)
Sales to other agencies Sale of treated surface water to City of Modesto Potable 29,125
29,125
0 29,125
NOTES: Volume is based on metered MID water production provided by the City in January 2026.

Optional Submittal Table 4-1 Wholesale: Total Uses for Potable and Non-Potable Water — Actual Water Code Section 10631(d)(1)
DWR NOTES: Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-

3. This table identifies the unit of measure selected in Submittal Table 2-3.

Total
2025 Actual Water Use
Subtotal Potable
Subtotal Non-Potable
Additional Description
(as needed)
#20..
- 951 -
Use Type
Drop down list
May select each use multiple
times
These are the only Use Types
that will be recognized by the
WUEdata online submittal tool
Potable or NonPotable
(OPTIONAL)
Drop down list
2030 (AF) 2035 (AF) 2040 (AF) 2045 (AF) 2050 opt (AF)
Single Family Potable 27,800 28,916 30,067 31,259 32,369 Multi-Family Potable 6,811 7,084 7,366 7,658 7,930
Commercial Potable 10,249 10,661 11,085 11,525 11,934
Industrial Potable 2,726 2,835 2,948 3,065 3,174
Institutional/Governmental Includes schools and
churches. Potable 2,704 2,813 2,925 3,041 3,149
Landscape Potable 3,148 3,275 3,405 3,540 3,666
Losses Potable 1,861 1,936 2,013 2,093 2,167
Landscape Raw water irrigation
wells Non-Potable 1,865 1,865 1,865 1,865 1,865
55,300 57,520 59,810 62,180 64,390
1,865 1,865 1,865 1,865 1,865
57,165 59,385 61,675 64,045 66,255
Submittal Table 4-2 Retail: Total Uses for Potable, and Non-Potable Water — Projected Water Code Section 10631(d)(1)
Projected Water Use
(Report To the Extent that Records are Available)
Additional
Description
(as needed)
NOTES: Potable demand projections are based on the forecasted population growth within the water service area and an estimated per‑capita water use of 175 gallons per capita per day (gpcd). Demand by use type is estimated using the average proportion of total water demand attributed to each use category over the past five years (2021–2025). Non-potable demands associated with landscape irrigation are expected to stay constant.

Subtotal Non-Potable
Subtotal Potable
Use Type
Drop down list
May select each use multiple
times
These are the only Use Types
that will be recognized by
the WUEdata online
submittal tool.

Potable or NonPotable
(OPTIONAL)
Drop down list
2030 (AF) 2035 (AF) 2040 (AF) 2045 (AF) 2050 opt (AF)
Sales to other agencies Sale of treated surface
water to City of Modesto Potable 38,710 40,264 41,867 43,526 45,073 38,710 40,264 41,867 43,526 45,073
0 0 0 0 0
38,710 40,264 41,867 43,526 45,073
Optional Submittal Table 4-2 Wholesale: Total Uses for Potable and Non-Potable Water — Projected Water Code Section 10631(d)(1)
NOTES: Projected surface water sales to the City of Modesto based on the City's projected water demands shown in Table 4-5 (DWR Table 4-2 Retail), and assuming that the City plans to use surface water to meet 70 percent of its total demands, with the remaining 30 percent met by groundwater. All treated surface water deliveries will be made in accordance with the ARTDA.

DWR NOTES: Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3. This table identifies the unit of measure selected in Submittal Table 2-3.

Total
Projected Water Use (Report To the Extent that Records are Available) Subtotal Potable
Subtotal Non-Potable
Additional Description
(as needed)
#20..
- 952 -
Are Future Water Savings Included in Projections?
Drop down list (y/n)
No
If "Yes" to above, state the section or page number, in the cell to the right, where citations of the codes, ordinances, or otherwise are utilized in demand projections are found.

Optional Suppliers may complete Optional Submittal Table 4-4 R to quantify the expected savings.

Are Lower Income Residential Demands Included In Projections? Drop down list (y/n) Yes
Optional If the method for accounting Lower Income Residential Demands has been included, provide page number where this accounting can be found. Refer to Section 4.2.6 Submittal Table 4-3 Retail: Inclusion in Water Use Projections Water Code Section 10631 (a), 10631 (d)(4)(A), and 10631 (d)(4)(B) NOTES:

DWR NOTES: Additional guidance is provided in Appendix K. #20..
- 953 -
Public Water System ID # Reported
in Table 2-1 R Reporting Period Submitted to DWR Water Loss Audit Program (yes/no) 2020 Yes
2021 Yes
2022 Yes
2023 Yes
2024 Yes
2020 No
2021 No
2022 No
2023 No
2024 No
2020 Yes
2021 Yes
2022 Yes
2023 Yes
2024 Yes
2020 Yes
2021 Yes
2022 Yes
2023 Yes
2024 Yes
2020 Yes
2021 Yes
2022 Yes
2023 Yes
2024 Yes
2020 Yes
2021 Yes
2022 Yes
2023 Yes
2024 Yes
2020 Yes
2021 Yes
2022 Yes
2023 Yes
2024 Yes
2020 Yes
2021 Yes
2022 Yes
2023 Yes
2024 Yes
Submittal Table 4-5 Retail: Water Loss Audit Reporting
Water Code Section 10631(d)(3)(A)
CA5010035
Central Turlock
DWR NOTES: Suppliers will provide a link to the WUEdata submittals of their Water Loss Audit Reports.

CA5010010
City of Modesto
CA5010023
South Turlock
CA5010034
North Turlock
CA5010029
Del Rio (Hillcrest)
CA5010033
Grayson
CA5010031
Ceres (Walnut Manor)
CA5010005
Salida(a)
#20..
- 954 -
2028 Real Water Loss
Standard per Unit per
day
Units for Real Water
Loss
Drop down list
Number of Units
(Connections or Miles
corresponding with units
selected)
Volume of Total Real Loss
(from AWWA Water Loss
Audit)
(AF)
2028 Apparent Water Loss
Standard per Unit per Day
Units for Apparent Water LossNumber of
Connections
Volume of Total Apparent
Loss
(from AWWA Water Loss
Audit)
(AF)
CA5010010
City of Modesto Yes 16
Gallons per Service
Connection per Day
(GPSCD)
75,123 1,027 12.2 13.4
Gallons per Service
Connection per Day
(GPSCD)
75,123 1,222 14.5
CA5010005
Salida No N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
CA5010031
Ceres (Walnut Manor) No N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A CA5010033
Grayson
Yes 13.7
Gallons per Service
Connection per Day
(GPSCD)
278 1.2 4.0 13
Gallons per Service
Connection per Day
(GPSCD)
278 3.2 10.2
CA5010029
Del Rio (Hillcrest) Yes 17.3
Gallons per Service
Connection per Day
(GPSCD)
408 40.0 87.5 37
Gallons per Service
Connection per Day
(GPSCD)
408 17.8 38.8
CA5010034
North Turlock No N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A CA5010023
South Turlock Yes 14.2
Gallons per Service
Connection per Day
(GPSCD)
336 12.2 32.3 9.1
Gallons per Service
Connection per Day
(GPSCD)
336 3.9 10.5
CA5010035
Central Turlock No N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A Submittal Table 4-6 Retail: Progress Towards 2028 Water Loss Standard Water Code Section 10631(d)(3)(C)
NOTES: Number of service connections and losses are from the water system's respective 2024-2025 fiscal year AWWA Water Loss Audit. Number of service connections includes both active and inactive connections. Refer to Section 4.3.2 for explanation of why some PWSs do not have a water loss standard.

Apparent Water Loss
Did the Water Board
Calculate a Water Loss
Standard for this Public Water System? (y/n)
If no, Supplier will not
complete this row.

Public Water System
ID #
Reported in Submittal
Table 2-1 R
Most Recent AWWA Water Loss Audit
Real Water Loss
Per Unit per Day
Most Recent AWWA Water Loss Audit
Apparent Water
Loss Per Unit per
Day
State Water Board Standard State Water Board Standard
#20..
- 955 -
Actual 2025 GPCD
(From SB X7-7
Compliance Form)
Did Supplier meet
the 2020 Target in
2025?
No Individual Target 228 175 Yes NA
Submittal Table 5-1 Retail: SB X7-7 2020 Target Progress Water Code Section 10608.40
NOTES:

Did Supplier
Achieve Targeted
Reduction for
2020?
2020 Target Actual 2020 GPCD
Regional Alliance
Target or
Individual
Target?
Drop down list
DWR NOTES:

Suppliers calculating a 2025 GPCD will need to complete and submit SB X 7-7 Compliance Tables to verify the use of SB X7-7 Methodologies.

Suppliers that were part of a merger or consolidation since 2020 see Chapter 5 and Appendix P for guidance.

NA=Not Applicable
Check the box if the Supplier was not an Urban Water Supplier during or before the 2020 UWMP reporting cycle. Proceed to the next table.

Only for suppliers that did not meet the
Target in 2020
See DWR NOTES below. Was Supplier part of a
merger or
consolidation since
2020?
#20..
- 956 -
Groundwater Type
Drop Down List
May use each category
multiple times
Potable or
Non-Potable
(OPTIONAL)
Drop down list
Location or Basin Name 2021 (AF) 2022 (AF) 2023 (AF) 2024 (AF) 2025 (AF) Alluvial Basin Potable San Joaquin Valley Groundwater
Basin
23,588 28,050 22,589 24,573 20,613
Alluvial Basin Non-Potable San Joaquin Valley Groundwater Basin
1,865 1,865 1,865 1,865 1,865
25,453 29,915 24,454 26,438 22,478
Submittal Table 6-1 Retail: Groundwater Volume Pumped
Water Code Section 10631(4) and 10631(4)(c)
DWR NOTES:

Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3. This table identifies the unit of measure selected in Submittal Table 2-3.

NOTES: Non-potable irrigation well use is not metered. Annual non-potable use is estimated based on the irrigable area of individual parks served.

Total
Check the box if the Supplier does not pump groundwater.

Proceed to the next table.

Check the box if all or part of the groundwater described below is desalinated. (OPTIONAL) Groundwater Type
Drop Down List
May use each category
multiple times
Potable or NonPotable
(OPTIONAL)
Drop down list
Location or
Basin Name
2021 (AF) 2022 (AF) 2023 (AF) 2024 (AF) 2025 (AF)
0 0 0 0 0
Submittal Table 6-1 Wholesale: Groundwater Volume Pumped Water Code Section 10631(4) and 10631(4)(C)
Check the box if the Supplier does not pump groundwater.

Proceed to the next table.

NOTES:

DWR NOTES:

Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3. This table identifies the unit of measure selected in Submittal Table 2-3.

Total
Check the box if all or part of the groundwater described below is desalinated. (OPTIONAL) #20..
- 957 -
N/A
N/A
Name of Wastewater
Collection Agency
Wastewater Volume
Metered or
Estimated?

OPTIONAL
Drop Down List
Volume of Wastewater
Collected from UWMP
Service Area 2025 (AF)
Name of Wastewater Treatment Plant
(WWTP) and Place ID Number
Drop down list
Is WWTP Located
Within UWMP
Area?
Drop Down List
City of Modesto Metered 22,771 City of Modesto WQCF, Place ID 241146 Yes City of Modesto Estimated 26,323
Other (provide name and ID in "NOTES"
field) No
Salida Sanitary District Estimated 1,344 Salida WWTP, Place ID 255081 No Grayson Community Services
District
Estimated 112
Grayson Comm Serv Dist. WTF, Place ID
227843
No
Del Rio Estimated 455
Other (provide name and ID in "NOTES"
field) No
City of Turlock Estimated 114
Turlock City, Turlock Regional Water
Quality Control Facility, Place ID 266737 No
51,120
Check the box if there is no wastewater collection system.

Proceed to the next table.

NOTES: The City of Modesto WQCF is the City's Sutter Avenue Primary Treatment Plant. The "Other" City of Modesto WWTP is the Jennings Road Treatment Plant. The Del Rio wastewater facilites consists of septic systems and packaged plants.

The total wastewater volume reported includes the volume treated at the Sutter Avenue primary plant and the flows subsequently treated at the Jennings Road secondary plant (double counting occurs due to the table formatting). Jennings Road plant total annual wastewater volume is estimated based on metered volume into the Sutter Avenue plant minus estimated primary solids flows removed, plus additional metered cannergy flows that are conveyed separately to the Jennings Road plant. Salida Sanitary District total annual volume estimated based on average flowrate of 1.2 MGD. Grayson Community Services District total annual volume estimated based on design flow capacity of 100,000 gallons per day. The City does not have wastewater flow data for the Del Rio service area or City of Turlock areas. Wastewater flows for these areas were estimated using an assumed return-to-sewer ratio of 60 percent of the water delivered to each service area.

Submittal Table 6-2 Retail: Wastewater Collected Within Service Area Water Code Section 10633(a)
Percentage of 2025 service area population served by wastewater collection system (OPTIONAL) Percentage of 2025 service area served by wastewater collection system (OPTIONAL) DWR NOTES: Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3. This table identifies the unit of measure selected in Submittal Table 2-3.

Additional Guidance: See Appendix M, Section M.21 for detailed guidance on this table.

Wastewater Collection Recipient of Collected Wastewater Total Wastewater Received from UWMP Service
Area in 2025:
#20..
- 958 -
Treatment
Level
Drop down list
Volume (AF)
Treatment
Level
Drop down list
Volume (AF)
Treatment
Level
Drop down list
Volume (AF)
Treatment
Level
Drop down list
Volume (AF)
Treatment
Level
Drop down list
Volume (AF) Name of other
entity
City of Modesto WQCF, Place
ID 241146
No 22,771 22,771 - - - - 22,693
City of Modesto
Jennings Road
Treatment Plant
Other (provide name and ID in
"NOTES" field) No 26,323 26,323 - Tertiary 20,331 - - - 49,094 49,094 0 20,331 0 0 22,693
Submittal Table 6-3 Retail: Wastewater Treatment and Outcomes Within UWMP Service Area Water Code Section 10633(b)
DWR NOTES:

Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3. This table identifies the unit of measure selected in Submittal Table 2-3.

IPR: Indirect Potable Reuse would have the treatment level of its end use requirement in the Level of Treatment drop-down.

Additional Guidance: See Appendix M, Section M.21 for detailed guidance on this table.

Water Recycled Outside of
UWMP Service Area
(enter data as applicable)
Effluent Discharge that is
not a Permitted Recycled
Water Use
(enter data as applicable)
Required Discharge for
Instream Flow
(enter data as applicable)
Delivered to Another Entity for Additional
Treatment
(enter data as applicable)
2025 Outcomes of Treated Wastewater
Check the box if no wastewater is treated or disposed of within the UWMP service area.

Proceed to the next table.

Does This Plant
Treat
Wastewater
Generated
Outside the
UWMP Service
Area?
(OPTIONAL)
Drop down list
Wastewater Treatment Plant
Name and Place ID Number
Drop down list
Total 2025
Volume of
Water Treated
(AF)
NOTES: The City of Modesto WQCF is the City's Sutter Avenue Primary Treatment Plant. The treatment level for the WQCF is left blank, as DWR does not provide an option for primary treatment. The "Other" City of Modesto WWTP is the Jennings Road Treatment Plant. Treatment level is shown as tertiary for the Jennings Road Treatment Plant; however, the facility produces and discharges both tertiary and secondary treated recycled water.

The total wastewater volume reported includes the volume treated at the Sutter Avenue primary plant and the flows subsequently treated at the Jennings Road secondary plant (double counting occurs due to the table formatting). The Sutter Avenue plant provides primary treatment only. All primary effluent from the Sutter Avenue plant is sent to the Jennings Road plant (located outside the City's service area). The Jennings Road plant also separately receives cannery wastewater effluent that is not treated at the Sutter Avenue plant. The Jennings Road plant produces both tertiary treated recycled water and secondary treated recycled water for use outside of the UWMP service area. Tertiary treated recycled water is provided to DPWD for agricultural irrigation (12,027 AFY in 2025), and secondary treated recycled water is used for application on City-owned ranch lands (8,304 AFY in 2025), for a total volume of 20,331 AFY as shown above.

Total
2025 Volume of
Wastewater
Received from
UWMP Service
Area
(As Reported in
Submittal Table
6-2 R) (AF)
Water Recycled Within
UWMP Service Area
(enter data as applicable)
#20..
- 959 -
Treatment
Level
Drop down list
Volume (AF)
Treatment
Level
Drop down list
Volume (AF)
Treatment
Level
Drop down list
Volume (AF)
Treatment
Level
Drop down list
Volume (AF)
Treatment
Level
Drop down list
Volume (AF) Name of
other entity
Total 0 0 0 0 0 0 0
DWR NOTES:

Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3. This table identifies the unit of measure selected in Submittal Table 2-3.

IPR: Indirect Potable Reuse would have the treatment level of its end use requirement in the Level of Treatment drop-down.

Additional Guidance: See Appendix M, Section M.21 for detailed guidance on this table.

NOTES:

Submittal Table 6-3 Wholesale: Wastewater Treatment and Discharge Within Service Area Water Code Section 10633(b)
Check the box if the Wholesale Supplier neither distributes nor provides supplemental treatment to recycled water.

Proceed to the next table.
2025 Volume of
Wastewater
Received from
UWMP Service
Area (AF)
2025 Outcomes of Treated Wastewater
Water Recycled Within
UWMP Service Area
(enter data as applicable)
Water Recycled Outside
of UWMP Service Area
(enter data as applicable)
Effluent Discharge that is
not a Permitted Recycled
Water Use
(enter data as applicable)
Required Discharge for
Instream Flow
(enter data as applicable)
Delivered to Another Entity for
Additional Treatment
(enter data as applicable)
Wastewater
Treatment Plant
Name and Place ID
Number
Drop down list
Does This Plant
Treat Wastewater
Generated
Outside the
UWMP Service
Area?
(OPTIONAL)
Drop down list
Total 2025
Volume of
Water
Treated
(AF)
#20..
- 960 -
Volume
Narrative page
number
(OPTIONAL)
0 Section 6.6.4
0 0 0 0 0 0 0
0 0 0 0 0 0 0
Total 0 0 0 0 0 0 0 0
Use Type
Drop down list
Potable or NonPotable
(after treatment if
treated)
(OPTIONAL)
Drop down list
Additional Information
(as needed)
DWR NOTES: Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3. This table identifies the unit of measure selected in Submittal Table 2-3.

Additional Guidance: See Appendix M, Section M.21 for detailed guidance on this table.

Potential recycled water use: a description of the feasibility of these uses must be included in the narrative.

Multiple Producers: If you have multiple recycled water producers, submit a separate table for each.

NOTES:
2025 (AF) 2030 (AF) 2035 (AF) 2040 (AF) 2045 (AF) 2050 (AF) Subtotal Potable
Subtotal Non-Potable
Check box if recycled water is not used and is not planned for use within the service area of the supplier. The supplier will only complete the column on "Potential Recycled Water Use" and submit an accompanying narrative on the feasibility of that potential recycled water use.

Submittal Table 6-4 Retail: Recycled Water Direct Beneficial Uses Within Service Area Water Code Section 10633 (c),(d),(e)
Potential Recycled
Water Use
Name(s) of Facility/is Producing (Treating) the Recycled Water (OPTIONAL) :

Name of Supplier Operating the Recycled Water Distribution System (OPTIONAL) Volume of Supplemental Water Added in 2025 (OPTIONAL) :

Source of 2025 Supplemental Water (OPTIONAL) :
#20..
- 961 -
Volume
Narrative page
number
(OPTIONAL)
0 Section 6.6.4
0 0 0 0 0 0 0
0 0 0 0 0 0 0
Total 0 0 0 0 0 0 0 0
NOTES:

Submittal Table 6-4 Wholesale: Current and Projected Recycled Water Uses Water Code Section 10633(c),(d),(e)
DWR NOTES:

Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3. This table reports the unit of measure selected in Submittal Table 2-3.

Additional Guidance: See Appendix M, Section M.21 for detailed guidance on this table.

Potential recycled water use: a description of the feasibility of these uses must be included in the narrative.

Multiple Producers: If you have multiple recycled water producers, submit a separate table for each.

Name of Receiving
Supplier or Direct Use
by Wholesale
Supplier
Potable or Non-Potable
(after treatment if
treated)
(OPTIONAL)
Drop down list
Additional
Information
(as needed)
Name(s) of Facility/is Producing (Treating) the Recycled Water (OPTIONAL) :

Name of Supplier Operating the Recycled Water Distribution System (OPTIONAL) :

Volume of Supplemental Water Added in 2025 (OPTIONAL) :

Source of 2025 Supplemental Water (OPTIONAL) :

Potential Recycled
Water Use
2025 (AF) 2050 (AF)
Subtotal Potable
Subtotal Non-Potable
2030 (AF) 2035 (AF) 2040 (AF) 2045 (AF)
#20..
- 962 -
2020 Projection
for 2025 (AF) 2025 Actual Use (AF)
0 0
NOTES:

Total
DWR NOTES:

Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3. This table identifies the unit of measure reported in Submittal Table 2-3 Additional Guidance: See Appendix M, Section M.21 for detailed guidance on this table.

Use Type
Drop Down list
Submittal Table 6-5 Retail: 2020 UWMP Recycled Water Use Projection Compared to 2025 Actual
Water Code Section 10633(e)
Check the box if recycled water was not used in 2025 nor previously projected for use in 2020.

Proceed to the next table.
2020 Projection for
2025 (AF) 2025 Actual Use (AF)
0 0
Submittal Table 6-5 Wholesale: 2020 UWMP Recycled Water Use Projection Compared to 2025 Actual
Water Code Section 10633(e)
DWR NOTES:

Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3. This table identifies the unit of measure selected in Submittal Table 2-3.

Additional Guidance: NOTES: See Appendix M, Section M.21 for detailed guidance on this Check the box if recycled water was not used or distributed by the supplier in 2025, nor projected for use or distribution in 2020.

Proceed to the next table.

Total
Name of Receiving Supplier or Direct
Use by Wholesale Supplier
#20..
- 963 -
Section 6.6.5
Name of Action Description
Expected Increase in
Recycled Water Use (AF)
0 0
Total (AF)
DWR NOTES:

Units of measure (AF, CCF, MG) MUST remain consistent with units reported in Submittal Table 2-3.

This table identifies the unit of measure selected in Submittal Table 2-3.

The unit conversion to Acre Feet addresses the Water Code's requirement that this value be provided NOTES: in acre-feet.

Submittal Table 6-6 Retail: Methods to Encourage Future Recycled Water Use Water Code Section 10633 (f)
Check the box if the Supplier does not plan to expand recycled water use in the future. Supplier will not complete the table below but will provide narrative explanation.

Provide page location of narrative in the UWMP
Unit Conversion to AF
Planned Implementation
Year
Drop Down List
(yes/no)
If Yes, Supplier
Name
Planned for
Use in Year
Type
Drop Down List
NOTES:

Submittal Table 6-7 Retail: Expected Future Water Supply Projects or Programs Water Code Section 10631(f)
DWR NOTES:

Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3. This table identifies the unit of measure reported in Submittal Table 2-3.

Check the box if some or all of the supplier's future water supply projects or programs are not compatible with this table and are described in a narrative format.

Check the box if there are no expected future water supply projects or programs that provide a quantifiable increase to the agency's water supply.

Proceed to the next table.

Planned
Implementation
Year
Joint Project with other
suppliers? Expected
Increase in
Water Supply
to Supplier
(This may be a
range) (AF)
Provide page location of narrative in the UWMP
Name of Future
Projects or
Programs
Additional
Description
(as needed)
Potable or
Non-Potable
(after treatment
if treated)
(OPTIONAL)
Drop Down list
#20..
- 964 -
Drop Down List
(yes/no)
If Yes, Supplier
Name
Provide page location of narrative in the UWMP
Check the box if some or all of the supplier's future water supply projects or programs are not compatible with this table and are described in a narrative format.

Check the box if there are no expected future water supply projects or programs that provide a quantifiable increase to the agency's water supply.

Proceed to the next table.

DWR NOTES: Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3. This table identifies the unit of measure reported in Submittal Table 2-3.

NOTES:

Submittal Table 6-7 Wholesale: Expected Future Water Supply Projects or Programs Water Code Section 10631(f)
Name of Future
Projects or Programs
Additional
Description
(as needed)
Potable or NonPotable
(after treatment
if treated)
(OPTIONAL)
Drop down list
Planned
Implementation
Year
Planned for
Use in Year
Type
Drop Down list
Expected
Increase in
Water Supply
to Supplier
(This may be a
range) (AF)
Joint Project with other
suppliers?
Water Supply
Drop down list
May use each category multiple times.

These are the only water supply
categories that will be recognized by
the WUEdata online submittal tool
Potable or Non-Potable
(after treatment if treated)
(OPTIONAL)
Drop Down list
Actual Volume
(AF)
Total Entitlement
(OPTIONAL)
See 'DWR Notes'
below (AF)
Purchased or Imported Water Purchased surface water from MID
Potable 29,125 67,200
Groundwater (not desalinated) Potable 20,613 -
Groundwater (not desalinated) Raw water irrigation wells Non-Potable 1,865 - 49,738 -
1,865 -
51,603 -
Submittal Table 6-8 Retail: Water Supplies — Actual
Water Code Section 10631 (b)
2025
NOTES: Volumes are based on actual surface water and groundwater production in 2025, consistent with DWR Table 4-1 Wholesale and DWR Table 6-1 Retail, respectively. The maximum surface water entitlement of 67,200 AFY is based on the ARTDA. The actual surface water supply quantity available will be based on the City’s increase in demand and will need to conform to requirements of the ARTDA.

DWR NOTES:

Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3. This table identifies the unit of measure selected in Submittal Table 2-3.

Total Entitlement: e.g. Water Right, Groundwater Allocation, Contracted Amount.

Total
Subtotal Potable
Subtotal Non-Potable
Additional Description
(as needed)
#20..
- 965 -
Water Supply
Drop down list
May use each category multiple times.

Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3. This table identifies the unit of measure selected in Submittal Table 2-3.

Total Entitlement: e.g. Water Right, Groundwater Allocation, Contracted Amount.

Total
Subtotal Potable
Subtotal Non-Potable
Additional Description
(as needed)
#20..
- 966 -
Water Supply
Reasonably
Available
Volume (AF)
Total
Entitlement
(OPTIONAL)
See 'DWR
Notes' below
Reasonably
Available
Volume (AF)
Total
Entitlement
(OPTIONAL)
See 'DWR
Notes' below
Reasonably
Available
Volume (AF)
Total
Entitlement
(OPTIONAL)
See 'DWR
Notes' below
Reasonably
Available
Volume (AF)
Total
Entitlement
(OPTIONAL)
See 'DWR
Notes' below
Reasonably
Available
Volume (AF)
Total
Entitlement
(OPTIONAL)
See 'DWR
Notes' below
Purchased or Imported Water Purchased surface water
from MID Potable 38,710 67,200 40,264 67,200 41,867 67,200 43,526 67,200 45,073 67,200 Groundwater (not desalinated) Potable 16,590 - 17,256 - 17,943 - 18,654 - 19,317 - Groundwater (not desalinated) Raw water irrigation
wells Non-Potable 1,865 - 1,865 - 1,865 - 1,865 - 1,865 - 55,300 - 57,520 - 59,810 - 62,180 - 64,390 -
1,865 - 1,865 - 1,865 - 1,865 - 1,865 -
57,165 - 59,385 - 61,675 - 64,045 - 66,255 -
Submittal Table 6-9 Retail: Water Supplies — Projected
Water Code Section 10631 (b)
Projected Water Supply (Report to the Extent Practicable) Drop down list
May use each category multiple times.

These are the only water supply
categories that will be recognized by the
WUEdata online submittal tool
Additional Detail on
Water Supply
Potable or NonPotable
(after treatment if
treated)
(OPTIONAL)
Drop Down list
2050 (opt)
Total
NOTES: Reasonably available volume of surface waster is based on the City's projected surface water purchases shown in Table 4-6 (DWR Table 4-2 Wholesale). This projected volume remains less than the City's maximum surface water entitlement of 67,200 AFY. The actual surface water supply quantity available will be based on the City’s increase in demand and will need to conform to requirements of the ARTDA. The reasonably available volume of groundwater is based on projected groundwater use shown in Table 6-6.
2030 2035 2040 2045
Subtotal Non-Potable
Subtotal Potable
DWR NOTES:

Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3.

Total Entitlement: e.g. Water Right, Groundwater Allocation, Contracted Amount. #20..
- 967 -
Reasonably
Available
Volume (AF)
Total
Entitlement
(OPTIONAL)
See 'DWR
Notes' below
(AF)
Reasonably
Available
Volume (AF)
Total
Entitlement
(OPTIONAL)
See 'DWR
Notes' below
(AF)
Reasonably
Available
Volume (AF)
Total
Entitlement
(OPTIONAL)
See 'DWR
Notes' below
(AF)
Reasonably
Available
Volume (AF)
Total
Entitlement
(OPTIONAL)
See 'DWR
Notes' below
(AF)
Reasonably
Available
Volume (AF)
Total
Entitlement
(OPTIONAL)
See 'DWR
Notes' below
(AF)
Surface water (not
desalinated) Tuolumne River Potable 38,710 - 40,264 - 41,867 - 43,526 - 45,073 - 38,710 - 40,264 - 41,867 - 43,526 - 45,073 -
0 - 0 - 0 - 0 - 0 -
Total 38,710 - 40,264 - 41,867 - 43,526 - 45,073 -
NOTES: Reasonably available volume of surface waster is based on the City's projected surface water purchases shown in DWR Table 4-2 Wholesale. This projected volume remains less than the City's maximum surface water entitlement of 67,200 AFY. The actual surface water supply quantity available will be based on the City’s increase in demand and will need to conform to requirements of the ARTDA.

Subtotal Potable
Subtotal Non-Potable
DWR NOTES:

Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3. This table identifies the unit of measure selected in a Submittal Table 2-3.

Total Entitlement: e.g. Water Right, Groundwater Allocation, Contracted Amount.

Submittal Table 6-9 Wholesale: Water Supplies — Projected Water Code Section 10631 (b)
Water Supply Projected Water Supply (Report to the Extent Practicable) 2030 2035 2040 2045 2050 (opt)
Drop down list
May use each category multiple
times.These are the only water
supply categories that will be
recognized by the WUEdata
online submittal tool
Additional Detail
on Water Supply
Potable or NonPotable
(after treatment if
treated)
(OPTIONAL)
Drop Down list
#20..
- 968 -
Water Delivery Product
drop down list
(If delivering more than one type of product recommend
using Table O-1C)
Retail Potable
Deliveries
Start Date of Reporting Period 1/1/2025
End Date of Reporting Period 12/31/2025
Is upstream embedded energy in the values reported? No
Units of Measure for Water AF
Total Utility
See DWR NOTES
Hydropower Net Utility
20,613 20,613
14,883,001 14,883,001
2,216 - 2,216
Quantity of Self-Generated Renewable Energy
0 kWh
Data Quality (Estimate, Metered Data, Combination of Estimates and Metered Data) Metered Data
Data Quality Narrative:

Narrative:

Volume of Water Entering Process
Energy Consumed (kWh)
Energy Intensity (kWh/vol. converted to MG)
Optional Submittal Table O-1B: Recommended Energy Reporting - SINGLE DELIVERY PRODUCT - TOTAL UTILITY APPROACH Energy consumption is based on the City's monthly metered electric bills during calendar year 2025. Energy usage includes energy consumed at all of the City's groundwater well sites throughout its contiguous and outlying service areas, which may also include some energy used by the wellhead treatment systems in place at some well sites. Energy usage reported excludes data for booster pump stations used at the City's storage reservoirs, which were not readily available. Volume of water entering process is based on the City's total potable groundwater volume pumped in 2025, consistent with DWR Table 6-1 Retail. Energy use shown does not include energy consumed at the MRWTP or for conveying surface water from the MRWTP to the City's terminal reservoirs.

Modesto City CouncilJune 23, 2026

Modesto City Council
June 23, 2026