Mountain House City Council
July 22, 2026

CALGreen. If the requirements of CALGreen are more stringent than the requirements of this Section, the CALGreen requirements shall apply. Project applicants shall refer to the City’s building and planning code for complete CALGreen requirements. For purposes of this Section, “Blue container,” “Green container,” “Commercial,” “Multi-family,” and “Organic waste” have the meanings set forth in Section 5-2-100 of this Code.
(b) For projects covered by CALGreen, the applicants must, as a condition of the City’s permit approval, comply with the following:
(1) Where five (5) or more Multi-family dwelling units are constructed on a building site, provide readily accessible areas that serve occupants of all buildings on the site and are identified for the storage and collection of Blue container and Green container materials, consistent with the three-container collection program offered by the City, or comply with provision of adequate space for recycling for Multifamily and Commercial premises pursuant to Sections 4.408.1, 4.410.2, 5.408.1, and

5.410.1 of the California Green Building Standards Code, 24 CCR, Part 11, as those sections may be amended, if the amended requirements are more stringent than the requirements effective January 1, 2020.
(2) New Commercial construction or additions resulting in more than 30% of the floor area shall provide readily accessible areas identified for the storage and collection of Blue container and Green container materials, consistent with the three-container collection program offered by the City, or shall comply with provision of adequate space for recycling for Multi-family and Commercial premises pursuant to Sections

4.408.1, 4.410.2, 5.408.1, and 5.410.1 of the California Green Building Standards Code, 24 CCR, Part 11, as those sections may be amended, if the amended requirements are more stringent than the requirements effective January 1, 2020. (3) Comply with CALGreen requirements and applicable law related to management of C&D, including diversion of Organic waste in C&D from disposal. Comply with the City’s Construction, Demolition and Landscaping Debris Recycling and Diversion requirements (Chapter 2 of Division 2 of Title 5), and all written and published City policies and/or administrative guidelines regarding the collection, recycling, diversion, tracking, and/or reporting of C&D.

SECTION 3. Effective Date. This Ordinance shall take effect thirty days after passage.

SECTION 4. Publication and Posting. The City Clerk shall comply with Government Code section 36933's publication and posting requirements.

SECTION 5. Severability. If any provision of this ordinance or the application thereof to any person or circumstance is held invalid, the remainder of the ordinance and the application of such provision to other persons or circumstances shall not be affected thereby.

Item 7.9
Mountain House                                               Page 187 of 741

Exhibit 1
Addition of Chapter 2 of Division 2 of Title 5
Chapter 2 - CONSTRUCTION, DEMOLITION AND LANDSCAPING DEBRIS RECYCLING AND DIVERSION 5-2-200 Title.

This Chapter shall be known as the "CONSTRUCTION, DEMOLITION AND LANDSCAPING DEBRIS RECYCLING AND DIVERSION ORDINANCE" of the City of Mountain House, and may be so cited. 5-2-201 Definitions.

For purposes of this chapter, the following definitions apply:
"Administrative Fee" means a non-refundable fee imposed by this Chapter in accordance with a fee schedule approved by the City Council.
"Applicable Project" means any construction, demolition, renovation or landscaping activity subject to the requirements of this Chapter, as set forth in Section 5-2-202, Applicable Projects. "Applicant" means any individual, firm, contractor, limited liability company, association, partnership, political subdivision, government agency, municipality, industry, public or private corporation, or any other entity whatsoever that applies to the City for the applicable permits or licenses to undertake any construction, demolition or landscape projects within the City. "Construction" means the building of any facility or structure or any portion thereof including any improvements to an existing facility or structure.
"Construction, Demolition and Landscaping Debris" means materials resulting from the construction, demolition or renovation of buildings or structures; or materials resulting from landscaping activities, including:
(1) Discarded materials generally considered non-water soluble and non-hazardous in nature, including but not limited to metals, glass, brick, concrete, asphalt material, pipe, gypsum, wallboard, insulation materials, roofing materials and lumber from the construction or demolition of a structure as part of a construction or demolition project or from the renovation of a structure and/or landscaping, including rocks, soils, tree remains, trees, and other vegetative matter resulting from land clearing, excavation, landscaping and development operations for a construction project; (2) Remnants of new materials, including but not limited to: cardboard, paper, plastic, inert material, wallboard, wood, and metal scraps from any construction, renovation and/or landscape project; (3) Earthen materials, including but not limited to dirt, clay, soil, loam, sand, rocks, stones and other materials resulting from excavation activities as part of a construction, demolition, renovation or landscaping project;
(4) Fixtures or other finished products that may be re-used in their current state rather than disposed of or processed in a recycling facility, including but not limited to doors, windows, bathroom fixtures, light fixtures, ceiling panels or molding;
(5) Any other non-hazardous wastes that are generated at construction, demolition, renovation or landscaping projects.
"Contractor" means any person or entity holding, or required to hold, a contractor's license of any type under the laws of the State of California, or who performs (whether as contractor, subcontractor, ownerbuilder, or otherwise) any construction, demolition, remodeling, renovation, or landscaping service relating to buildings or accessory structures in the City of Mountain House. "Demolition" means the decimating, razing, tearing down or wrecking of any facility, structure, pavement or building, whether in whole or in part, whether interior or exterior.

Item 7.9
Mountain House                                               Page 188 of 741

"Designated Recyclable and Reusable Materials" means:
(1) Corrugated Cardboard (OCC);
(2) Inert materials generally used in construction or renovation including but not limited to, asphalt, concrete, rock, stone, mortar and brick;
(3) Metals, including all metal scrap including, but not limited to, pipes, siding, window frames, door frames, flashing materials, and fences;
(4) Roofing materials including wood shingles and shakes as well as asphalt, stone and slate based roofing material;
(5) Salvageable materials and structures including, but not limited to doors, windows, fixtures, hardwood flooring, sinks, bathtubs and appliances;
(6) Vegetative materials;
(7) Excavation materials including, but not limited to dirt, clay, loam, sand, stones, rocks or any combination thereof;
(8) Non-hazardous wallboard materials including gypsum and drywall; (9) Wood materials including, but not limited to dimensional lumber, fencing or wood that is not chemically treated, creosoted, CCA pressure treated, contaminated, painted or sealed; (10) Any other materials from the construction, demolition or renovation of structures that the City determines can be diverted due to the acceptance such materials by recycling facilities, reuse facilities, or accessible markets.
“Director” means the City Manager or the City Manager’s designee. "Diversion" means the use of material for any purpose other than disposal. "Diversion Plan" means a completed City-provided form submitted before the issuance of a building and/or demolition permit, approved by Solid Waste Personnel for the purpose of compliance with this Chapter.
"Diversion Report" means a completed City-provided form submitted quarterly and upon completion of an Applicable Project that is used by Solid Waste Personnel for the purpose of determining compliance with this Chapter.
"Good Faith Effort" means and is applicable to projects where the availability of markets for construction and demolition debris were a determining factor in not meeting full compliance and where sufficient documented evidence, such as weight receipts, demonstrate that the Applicant attempted to divert construction and demolition debris but could not achieve full compliance. "Inert material" means asphalt, concrete, masonry, brick, tile, ceramics, gravel, rock, soil, sand, asphalt, brick, ceramic products, plaster, clay products and similar materials. "Landscape Professional" means any person that provides landscaping services for a fee within the City. "Landscaping" means the installation, removal or maintenance of plantings, flowers, shrubs, trees or any other vegetation.
"Non-compliant" means the failure to adhere to the requirements of this Chapter. "Recycling" means the process of collecting, sorting, cleansing, treating and/or the reconstitution of materials that would otherwise become solid waste and returning them to the economic mainstream in the form of a raw material for new, reused or reconstituted products which meet the quality standards necessary for use in the marketplace.
"Renovation" means any change, alteration, addition, replacement, or modification to an existing structure.
"Reuse" means further or repeated use of construction and demolition debris. "Solid Waste Personnel" means persons employed by the City of Mountain House to administer solid waste programs.
"Vegetative materials" means trees, tree parts, shrubs, stumps, logs, brush or any other type of plants that are cleared from a site for construction, demolition, renovation or landscaping purposes.

Item 7.9
Mountain House                                               Page 189 of 741

5-2-202 Applicable Projects.

Projects subject to the requirements of this Chapter include any project which consists of one (1) or more of the following:
(a) Construction of a new residential, commercial, industrial or institutional building or structure that is equal to or greater than one thousand two hundred (1,200) square feet; (b) Construction of multifamily dwellings, such as duplexes or apartment complexes; (c) Construction of buildings accessory to residential or multifamily dwellings that are equal to or greater than one thousand two hundred (1,200) square feet; (d) Demolition of any building or structure, or a portion thereof, that is equal to or greater than one thousand two hundred (1,200) square feet;
(e) Renovation of any building or structure, where the area is equal to or greater than one thousand two hundred (1,200) square feet;
(f) Other projects deemed applicable as determined by Solid Waste Personnel, including but not limited to the demolition, construction or renovation of roofing, walls, siding, ceiling tile and all other projects where the area or surface area of the project is equal to or greater than one thousand two hundred (1,200) square feet; or
(g) Landscaping operations whereby Landscape Professionals, as a course of business, perform landscaping functions at one (1) or more locations within the City and as a result of these operations collect and dispose of vegetative and/or inert materials. 5-2-203 Exemptions.

The following projects shall not be subject to the provisions of this Chapter:
(a) Construction or demolition necessary to remedy an imminent health or safety condition, or performed in conjunction with an emergency, as determined by the City Manager, including but not limited to fire, earthquake, or flood.
(b) A project contaminated by hazardous substances or hazardous waste as defined by the state or federal law.
(c) Construction of agricultural structures, excluding structures used as dwellings by humans. (d) Construction, Demolition or Renovation projects that can be demonstrated to have an insignificant waste stream, as determined by Solid Waste Personnel, may be exempted from this Chapter. (e) Landscape Professionals who perform Landscaping operations at locations within the City areas shall be exempt from the provisions of this Chapter, with the exception of Section 5-2-204 Diversion Requirements, and shall make available, upon the request of Solid Waste Personnel, weight receipts and/or other information to verify that collected materials are diverted and/or disposed of in compliance with the requirements of this Chapter.
(f) Other projects may be deemed exempt where they can be demonstrated to be consistent with the intent of this Chapter, as determined by Solid Waste Personnel. 5-2-204 Diversion Requirements.

To the highest extent feasible, Construction, Demolition and Landscaping Debris shall be diverted from landfilling unless otherwise exempt under Section 5-2-203. Applicable Projects shall, at a minimum, meet the construction and demolition materials diversion requirements defined and set forth by California Code of Regulations, Title 24's California Green Building Standards Code also known as the CALGreen Code.

Landscape debris generated from Applicable Projects including inert soil, vegetative and excavation materials shall be diverted at a rate of ninety percent (90%). Diversion Reports shall be required for verification of such activities. Acceptable diversion methods are as follows:

Item 7.9
Mountain House                                               Page 190 of 741

(a) Providing or facilitating the verifiable reuse of materials, including, but not limited to, the sale or the donation of the material to an organization that specializes in reusing left over materials. (b) Delivering all construction and demolition debris solely to a solid waste site designated by the City Manager.
(c) Source separating materials into individual constituents as defined under "Designated Recyclable and Reusable Materials" and directing them to any reuse or recycling facility acceptable to the Director.

Any remaining materials shall be taken to a solid waste site as designated by the Director. 5-2-205 Reporting Requirements.
(a) The following plan shall be submitted and approved for all Applicable Projects:
(1) Every Applicant shall submit a properly completed Diversion Plan as a requirement of the construction and demolition process. The plan may cover multiple structures for lots where project activity is occurring at the same time by the same Applicant. The Diversion Plan shall identify the materials to be recycled, reused and/or disposed of and shall list facilities and providers to be used. An Administrative Fee for each Applicable Project must be submitted with the Diversion Plan. (2) Notwithstanding any other provisions of this Chapter, no construction or demolition permit shall be issued for any Applicable Project unless and until Solid Waste Personnel have approved the Diversion Plan. Solid Waste Personnel shall approve a Diversion Plan only if it is determined that it is complete and meets all requirements set forth in this subsection (a). If all of requirements have been met, the Diversion Plan shall be marked "Plan Approved", a copy of the plan shall be returned to the Applicant, and the Community Development Department shall be notified that it has been approved. (3) If Solid Waste Personnel determine that the Diversion Plan is incomplete or fails to meet all requirements set forth in this subsection (a), it shall be returned to the Applicant marked "Plan Denied" or "Further Explanation Required" and shall include a brief notation stating what is required for approval.

The Applicant shall then resubmit the Diversion Plan with the required information for subsequent review. (b) The following documentation shall be submitted upon the completion of all Applicable Projects:
(1) A final Diversion Report shall be returned to Solid Waste Personnel no later than thirty (30) days following finalization of the permit or completion of an Applicable Project demonstrating that compliance with this Chapter has been met.
(2) The documentation accompanying the Diversion Report shall consist of photocopies of receipts and weight tags or other records of measurement or equivalent documentation from recycling facilities, deconstruction contractors, and landfill and disposal facilities. If City-owned facilities are utilized solely, photocopies of weight receipts shall meet the reporting requirements. (3) All reports and documentation submitted pursuant to this section are subject to verification and approval.
(4) Applicants submitting false information in the form of reports, documents, statements, receipts; weight tags or other records of measurement regarding materials recycled or diverted shall be deemed Non-compliant to this Chapter.
(5) Applicants failing to submit the Diversion Report and documentation within thirty (30) days of project completion shall be deemed Non-compliant to this Chapter. 5-2-206 Administrative Fee.

A non-refundable Administrative Fee shall be charged for Applicable Projects according to a fee schedule approved by the City of Mountain House City Council.

Item 7.9
Mountain House                                               Page 191 of 741

5-2-207 Non-Compliance Fee.
(a) A non-compliance fee shall be charged for each Applicable Project that has been deemed Noncompliant according to a fee schedule approved by the City of Mountain House City Council. (b) Any Applicable Project completed without a permit issued shall be deemed Non-compliant and shall be charged a non-compliance fee according to a fee schedule approved by the City of Mountain House City Council.
(c) Good Faith Effort: If Solid Waste Personnel determine that an Applicable Project has not met the requirements of this Chapter, it shall also be determined whether the Applicant has made a good faith effort to comply with this Chapter. In making this determination, the availability of markets for construction and demolition debris, the size of the project and the documented efforts of the Applicant to divert construction and demolition debris shall be considered. If Solid Waste Personnel determine that a good faith effort has been made, a non-compliance fee shall not be charged. If it is determined that a good faith effort has not been made, a non-compliance fee shall be charged according to a fee schedule approved by the City of Mountain House City Council.
5-2-208 Enforcement Designation.

The City of Mountain House City Council shall designate the Director as the officer responsible for the administration and enforcement of the provisions of this Chapter. The Director may appoint Solid Waste Personnel to assist in the enforcement of this Chapter. 5-2-209 Enforcement.

Applicants undertaking a construction, demolition, or renovation project by applying for City permits are responsible for compliance with the diversion requirements of this Chapter. (a) Owner-Applicants shall be responsible for agents, other than paid contractors, that apply for permits on their behalf. Owner-Applicants with unpaid non-compliance fees shall receive a Code Violation recorded on the respective property as outlined in Section 5-2-210. (b) Contractor-Applicants with unpaid non-compliance fees shall be denied future Diversion Plan approvals until unpaid non-compliance fees are paid in full. 5-2-210 Notice of Code Violation and Release of Notice of Code Violation. (a) Recording Notice: When Solid Waste Personnel determine that a violation of this Chapter exists against an Owner-Applicant or the agent thereof, a Notice of Code Violation may be recorded against the property. Prior to recordation, the City shall send written notification to the property owner(s) of record of the intent to record the Notice of Code Violation against the property. Notice to the owner(s) shall be sent to the address shown on the most recent tax roll. Failure of the owner to receive such notice shall not affect the Notice of Code Violation.
(b) Release of Notice: Solid Waste Personnel shall submit a Release of Notice of Code Violation to the County Recorder when non-complying conditions have been corrected, removed or non-compliance fees have been paid in full.
5-2-211 Disposition of Fees.

All fees collected under the provisions of this Chapter shall be paid into the City Treasury.

Item 7.9
Mountain House                                               Page 192 of 741

5-2-212 Severability.

If any section, subsection, sentence, clause or phrase of this Chapter is for any reason held to be invalid, such decision shall not affect the validity of the remaining portions of this Chapter. The City declares that it would have adopted this Chapter, including every section, subsection, sentence, clause and phrase, irrespective of whether one (1) or more sections, subsections, sentences, clauses or phrases is held invalid.

To this end, the provisions of this Chapter are declared to be severable.

Item 7.9
Mountain House                                               Page 193 of 741 TITLE: Approve Resolution Placing Delinquent Utility Account Service Charges on the Property Tax Roll
MEETING DATE: July 22, 2026
PREPARED BY: Sarah Ragsdale, Administrative Services Director

RECOMMENDATION
Staff recommends that the City Council approve a resolution to place delinquent utility account service charges on the San Joaquin County property tax roll for fiscal year 2026/2027.

BACKGROUND
The City of Mountain House provides water, wastewater, and stormwater service to properties within the City and charges fees for that service under California Health and Safety Code section 5471. Staff has identified approximately 277 delinquent utility accounts.

Before incorporation, these utilities were operated by the Mountain House Community Services District, which collected delinquent charges and penalties on the County property tax roll under its community services-district authority (Gov. Code, § 61115). With incorporation, the City succeeded to the utility function. That district-specific authority no longer governs; the authority available to a city is found in Health and Safety Code sections 5470 through 5473.11.

The City already addresses delinquencies by recording liens against the delinquent account owner’s property under Health and Safety Code section 5473.11. Recording a lien secures the debt but generally does not produce payment until the owner sells or refinances. Collecting the delinquency on the tax roll, by contrast, causes the past-due amount to be paid when the annual property tax bill is paid. The two collection tools are complementary; electing tax-roll collection does not eliminate the City's lien remedy.

On June 9, 2026, the City Council approved a resolution to collect delinquent utility account service charges on the San Joaquin County property tax roll beginning with fiscal year 2026/2027 and directed staff to prepare the written report of delinquent accounts, file it with the City Clerk, give the required notices, and schedule a public hearing.

DISCUSSION
Tonight's meeting is the final step in the process of placing delinquent utility charges on the property tax roll. This step—holding a hearing and considering the adoption of a resolution formally placing the charges on the tax roll—is part of the annual process.

Item 8.1
Mountain House                                               Page 194 of 741 California Health and Safety Code section 5471 provides that cities can charge fees for water, wastewater, and stormwater services. Section 5473 allows cities to collect those fees on the tax roll, and section 5473a permits the City to make that election as to delinquent charges only. As noted above, on June 9 the Council adopted Resolution 2026-49 electing to have the delinquent charges collected on the tax roll.

Following that action, staff completed the remaining statutory steps required to implement tax-roll collection. The process for collecting the delinquent charges on the tax roll is as follows:
• Adopt Resolution (Two-Thirds Vote). Under Health and Safety Code section 5473, the City Council must adopt a resolution, approved by a two-thirds vote, electing to collect delinquent utility charges on the tax roll.

This action was approved on June 9, 2026.
• Prepare and File the Written Report. The City prepares a written report identifying each delinquent parcel and the corresponding past-due charges and files the report with the City Clerk (Health & Saf. Code, § 5473).

Attachment A identifies the delinquent accounts proposed for placement on the tax roll as of the agenda publication date. Any account paid in full before tonight's hearing will be identified during the hearing and recommended for removal. Accounts paid after tonight's hearing, but before the County's submission deadline, will also be removed from the report. • Provide Public Notice. Because this is the first year the City will collect delinquent utility charges on the property tax roll, two forms of notice were required:
o Published Notice. Notice was published in the Tracy Press on July 10 and July 17, 2026, in accordance with Government Code section 6066.
o Mailed Notice. Letters were mailed to 407 delinquent account holders on June 23, 2026, providing 30 days for customers to pay outstanding balances, establish payment arrangements, or contact the City regarding their accounts (Health & Saf. Code, § 5473.1). • Hold the Public Hearing. At the noticed public hearing, the City Council considers any objections or protests, may revise or modify the delinquent charges as appropriate, and approves the final report (Health & Safety Code, § 5473.3).

The public hearing will be held during tonight's meeting. • File the Report with the County Auditor-Controller. On or before August 10, 2026, the City Clerk will file the adopted report with the San Joaquin County Auditor-Controller, who will place the approved delinquent charges on the current property tax roll (Health & Safety Code, § 5473.4).

Item 8.1
Mountain House                                               Page 195 of 741 To avoid placement on the tax roll, delinquent account holders must pay outstanding balances by August 3, 2026, allowing staff sufficient time to process payments and submit the final report to the County.

The table below summarizes the actions taken since the City Council's June 9, 2026, approval of the taxroll collection process.

Activity Status
Letters Mailed June 23, 2026
Quantity Mailed 407
Days Between Mailing and Public Hearing 30
Accounts Removed (Paid in Full / Payment Plan) 111 paid; 11 payment plans Accounts Remaining – PFC Underbilling 17
Accounts Remaining – Meter Reading Issues 40
Accounts Remaining on Proposed Tax Roll 277 of 407
Delinquencies to be Added to Tax Roll $576,259.41
Average Delinquency $2,080.36
Public Hearing Notices Published July 10 & 17
Payment Deadline to Avoid Tax Roll August 3
The number of delinquent accounts proposed for placement on the property tax roll is greater than in previous years for the following reasons:
• Conversion to In-House Utility Billing: Staff encountered issues during the conversion to the new utility billing system. Although data from the previous system was transferred, staff identified inaccuracies in information such as meter serial numbers and locations and corrected those records as they were discovered. Staff also identified software issues, including automatic payment processing, that required research and correction. Staff has substantially improved the reliability of the software and related billing processes. • Field Issues: With the conversion to in-house billing, staff discovered ongoing issues with meter reading equipment and data transmission. As a result, more than 600 accounts were billed based on estimated usage. Over time, field technicians inspected and repaired or replaced equipment and, when necessary, obtained manual meter readings. Staff continues investigating solutions to improve data transmission reliability. As equipment issues have been resolved, accounts are increasingly being billed based on actual meter readings.

Item 8.1
Mountain House                                               Page 196 of 741 • Reduced Use of Service Terminations: Termination of utility service is one of the City's most effective collection tools for delinquent accounts. The Water Shutoff Protection Act (SB 998), which became effective in 2020, established additional requirements that must be satisfied before service can be terminated. Prior to the conversion to in-house billing, Utility Billing staff maintained termination and property lien schedules in compliance with SB 998. During the billing system conversion, staff focused on verifying account information to ensure billing accuracy, which limited the use of service terminations. As utility billing processes and metering reliability have improved, staff intends to resume the full range of collection remedies available under SB 998, which is expected to reduce future delinquencies.

Staff expects the number of delinquent accounts placed on the tax roll to decline significantly in future years as utility billing processes continue to stabilize and standard collection practices resume.

FISCAL IMPACT
Collecting delinquent charges on the tax roll is expected to improve recovery of approximately 277 delinquent utility accounts. The aggregate amount of the current delinquencies proposed for collection is approximately $576,259, with an average delinquency of approximately $2,080 per account. Direct costs associated with the process include publication, mailing notices, and the 1% fee charged by the San Joaquin County Auditor-Controller. Amounts collected reimburse the City's water, wastewater, and stormwater enterprise funds (Health & Saf. Code, § 5471). The $100 fee assessed on delinquent accounts helps offset these administrative costs.

STRATEGIC PLAN
The proposed action supports the City's Strategic Plan, adopted April 9, 2025, by:
• Promoting fiscal responsibility through the timely collection of utility service charges. • Protecting the financial sustainability of the City's water, wastewater, and stormwater enterprise funds.
• Supporting efficient and accountable utility operations through consistent billing and collection practices.

CEQA
This action is not a project subject to the California Environmental Quality Act (CEQA).

ACTION FOLLOWING CITY COUNCIL APPROVAL
Item 8.1
Mountain House                                               Page 197 of 741 Following City Council approval, the City Clerk will file the adopted report with the San Joaquin County Auditor-Controller for placement of the approved delinquent utility charges on the 2026/2027 property tax roll.

ATTACHMENTS
Attachment A – Report of Delinquent Utility Accounts
Attachment B – Resolution Approving Report of Delinquencies, as Revised, Corrected, or Modified Item 8.1
Mountain House                                               Page 198 of 741 ACCOUNT APN # NAME SERVICE ADDRESS MAILING ADDRESS CITY,STATE,ZIP

CURRENT PAST

DUE BALANCE
7/16/2026 FEE TOTAL
1 390-00023-01 262-150-53 THANGAVEL RAMESH 563 W ELLSWORTH AVE 563 W ELLSWORTH AVE MOUNTAIN HOUSE, CA 95391 $ 1,348.62 $ 100.00 $ 1,448.62 2 390-00040-01 256-370-40 DHALIWAL, BALPREET S/PRABJOT K 394 W AVENTINO AVE 394 W AVENTINO AVE MOUNTAIN HOUSE, CA 95391 4,135.13 100.00 4,235.13 3 390-00073-05 256-070-23 LAKKOJU, GOVINDARAJULU 289 N ORINDA ST 425 N ALBANY ST MOUNTAIN HOUSE, CA 95391 3,208.45 100.00 3,308.45 4 390-00093-01 262-280-16 PUCHAKAYALA ANAND KISHORE 1313 S COW CT 1313 S COW CT MOUNTAIN HOUSE, CA 95391 2,431.02 100.00 2,531.02 5 390-00115-01 262-200-65 KULKARNI JAGDISH 1040 S MODENA ST 1040 S MODENA ST MOUNTAIN HOUSE, CA 95391 2,793.45 100.00 2,893.45 6 390-00138-01 262-150-21 VIJ GAUTAM/DEEPALI 1127 S CRAWFORD DR 1127 S CRAWFORD DR MOUNTAIN HOUSE, CA 95391 4,044.08 100.00 4,144.08 7 390-00152-01 262-280-63 SAIKOMOL WILASINEE 472 E DEB CORALLO TERR 472 E DEB CORALLO TERR MOUNTAIN HOUSE, CA 95391 3,527.39 100.00 3,627.39 8 390-00201-01 262-290-37 GANGOPADHYAY, MANIK 479 E LEONARDO WAY 1280 S CENTRAL PKWY MOUNTAIN HOUSE, CA 95391 2,731.70 100.00 2,831.70 9 390-00319-01 262-240-39 DINGISWAYO ASFAO 1548 S BELLA VITA ST 1548 S BELLA VITA ST MOUNTAIN HOUSE, CA 95391 662.86 100.00 762.86 10 390-00379-01 262-200-82 GIRIRAJU SAKAPPA/SUJEETHA 275 E VITA AVE 275 E VITA AVE MOUNTAIN HOUSE, CA 95391 3,969.36 100.00 4,069.36 11 390-00399-02 262-180-06 KUMARAGURUPARAN GOWRI 429 E MARCELLO AVE 429 E MARCELLO AVE MOUNTAIN HOUSE, CA 95391 675.36 100.00 775.36 12 390-00432-01 262-230-08 OLACHERY SHAN 350 E RAMSEY DR 350 E RAMSEY DR MOUNTAIN HOUSE, CA 95391 879.26 100.00 979.26 13 390-00436-01 262-220-48 PATHIKONDA PADMANAB/ARCHANA 294 E BELLA SERATA AVE 294 E BELLA SERATA AVE MOUNTAIN HOUSE, CA 95391 3,258.65 100.00 3,358.65 14 390-00449-01 262-160-24 MATCHA KRISHNA 1251 S WILSHIRE AVE 1251 S WILSHIRE AVE MOUNTAIN HOUSE, CA 95391 1,800.00 100.00 1,900.00 15 390-00517-02 262-160-20 TALLAPRAGADA RAGHUNATH PAVAN 1234 S WILSHIRE AVE 1234 S WILSHIRE AVE MOUNTAIN HOUSE, CA 95391 4,292.85 100.00 4,392.85 16 390-00520-01 262-220-40 REHMAN IMRAN 246 E BELLA SERATA AVE 29606 JUNIPER RANCH RD FULSHEAR, TX 77441 824.26 100.00 924.26 17 390-00556-01 262-300-32 SU PETER 404 E TEIXEIRA AVE 16630 COWELL ST SAN LEANDRO, CA 94578 2,085.18 100.00 2,185.18 18 390-00598-01 262-260-40 GAPOL KEITH 63 E RAMSEY DR 63 E RAMSEY DR MOUNTAIN HOUSE, CA 95391 3,318.37 100.00 3,418.37 19 390-00720-01 262-370-45 WAGNER NEIL 533 E ISIDORO AVE 533 E ISIDORO AVE MOUNTAIN HOUSE, CA 95391 800.00 100.00 900.00 20 390-00728-02 262-230-35 ABBURI KRISHNA HEMANTH 1448 S BELLA VITA ST 1448 S BELLA VITA ST MOUNTAIN HOUSE, CA 95391 1,192.00 100.00 1,292.00 21 390-00758-01 262-340-38 GOPAKUMAR GOPALAN 1549 S BANCROFT WAY 1549 S BANCROFT WAY MOUNTAIN HOUSE, CA 95391 3,865.13 100.00 3,965.13 22 390-00766-01 262-230-46 PITTA NARAYANA 1429 S TERRA VERDE ST 1429 S TERRA VERDE ST MOUNTAIN HOUSE, CA 95391 4,140.83 100.00 4,240.83 23 390-00841-01 262-340-17 GUTIERREZ TIMOTHY 519 W WARREN DR 519 W WARREN DR MOUNTAIN HOUSE, CA 95391 2,599.40 100.00 2,699.40 24 390-00874-01 262-200-28 PATIL GIREESH 277 E PARCO AVE 277 E PARCO AVE MOUNTAIN HOUSE, CA 95391 2,970.21 100.00 3,070.21 25 390-00906-01 262-200-31 SUTHRAM SANTHOSH 295 E PARCO AVE 295 E PARCO AVE MOUNTAIN HOUSE, CA 95391 995.55 100.00 1,095.55 26 390-00944-01 262-160-05 THIRUMALAI SUNDARARAJAN 1255 S DURANT TERR 1255 S DURANT TERR MOUNTAIN HOUSE, CA 95391 2,618.40 100.00 2,718.40 27 390-00966-01 262-370-22 PARAMESH FAMILY RVOCABLE TRUST 448 E ALBERTINA AVE 448 E ALBERTINA AVE MOUNTAIN HOUSE, CA 95391 1,369.22 100.00 1,469.22 28 390-00967-01 262-310-43 MONDAL ARNAB/BHASIN GUNJAN 1401 S DURANT TERR 4535 PISANO TERRACE DUBLIN, CA 94568 2,567.31 100.00 2,667.31 29 390-00982-02 262-300-03 BHATIA RAJESH KUMAR 1412 S PROSPERITY ST 1412 S PROSPERITY ST MOUNTAIN HOUSE, CA 95391 561.73 100.00 661.73 30 390-01017-02 262-330-42 BOREDDY SINDHURA 625 W WARREN DR 625 W WARREN DR MOUNTAIN HOUSE, CA 95391 1,309.73 100.00 1,409.73 31 390-01056-01 262-360-11 SANDHU, LOVENEET 1428 S WILSHIRE AVE 1428 S WILSHIRE AVE MOUNTAIN HOUSE, CA 95391 863.26 100.00 963.26 32 390-01102-01 262-260-15 VANGARU SRINIVASA PRASAD 1263 S PALERMO LN 1263 S PALERMO LN MOUNTAIN HOUSE, CA 95391 1,131.01 100.00 1,231.01 33 390-01122-01 262-330-28 BISCARRA SUEANN DELAROSA 675 W WARREN DR 675 W WARREN DR MOUNTAIN HOUSE, CA 95391 1,011.58 100.00 1,111.58 34 390-01140-01 262-330-26 GINODIA DEVESH 1560 S HART DR 1560 S HART DR MOUNTAIN HOUSE,CA 95391 2,332.23 100.00 2,432.23 35 390-01185-01 262-41-037 RAZ KHOSHAL 51 W ROCCOLTA GLEN 25852 FIVE CANYONS PKWY CASTRO VALLEY, CA 94522 848.26 100.00 948.26 36 390-01204-02 262-43-035 ADDEPALLI VEERASEKHAR 96 E STEFANO AVE 96 E STEFANO AVE MOUNTAIN HOUSE, CA 95391 812.26 100.00 912.26 37 390-01217-01 262-40-014 SIMMS DAMARIO 260 E NATASHA AVE 260 E NATASHA AVE MOUNTAIN HOUSE, CA 95391 1,757.17 100.00 1,857.17 38 390-01244-01 262-350-55 GAINES DONELL 1489 S BARKER ST 1489 S BARKER ST MOUNTAIN HOUSE, CA 95391 1,253.22 100.00 1,353.22 39 390-01250-01 262-310-03 RIVERA ERICA 655 W CROCKER LN 655 W CROCKER LN MOUNTAIN HOUSE, CA 95391 1,050.56 100.00 1,150.56 40 390-01344-01 262-270-18 NARAN RAJESH 1252 S LA SPEZIA LN 1252 S LA SPEZIA LN MOUNTAIN HOUSE, CA 95391 2,405.00 100.00 2,505.00 41 390-01407-01 262-530-08 SIDI CLAUDIO 1082 S NOBLE FIR PLACE 1082 S NOBLE FIR PLACE MOUNTAIN HOUSE, CA 95391 1,751.20 100.00 1,851.20 42 390-01410-01 262-530-12 RAMPALLI PHANEEDRA 437 E FUSCHIA WAY 2633 DAPPLE GRAY LN LEANDER, TX 78641 2,695.43 100.00 2,795.43 43 390-01443-01 262-530-02 STEWART MELISSA 1084 S YERBA BUENA CT 1084 S YERBA BUENA CT MOUNTAIN HOUSE, CA 95391 843.82 100.00 943.82 44 390-01488-01 262-490-34 THIRUMURTHI RAJENDRA KUMAR 240 W LIMERICK AVE 240 W LIMERICK AVE MOUNTAIN HOUSE, CA 95391 932.12 100.00 1,032.12 45 390-01499-01 262-500-37 HORNAGE NICOLE 1367 S WILEY PLACE 1729 N 1ST ST APT 11213 SAN JOSE, CA 95112 724.95 100.00 824.95 46 390-01548-02 262-540-48 KISHORE FNU GORIE LAKSHMI 2183 S COOPERATION ST 2183 S COOPERATION ST MOUNTAIN HOUSE, CA 95391 1,513.96 100.00 1,613.96 47 390-01570-01 262-410-60 KONDA PRAVEEN 72 W PHENIZY AVE 72 W PHENIZY AVE MOUNTAIN HOUSE, CA 95391 1,372.74 100.00 1,472.74 48 390-01573-01 262-490-44 HURTADO NOEL 1358 S STANZA PL 1358 S STANZA PL MOUNTAIN HOUSE, CA 95391 2,690.97 100.00 2,790.97 49 390-01577-01 262-540-34 YI LINA 305 E FORSYTHIA WAY 305 E FORSYTHIA WAY MOUNTAIN HOUSE, CA 95391 1,139.79 100.00 1,239.79 50 390-01587-01 262-540-33 YU CHENHAN/SONG YANYI 319 E FORSYTHIA WAY 319 E FORSYTHIA WAY MOUNTAIN HOUSE, CA 95391 820.26 100.00 920.26 51 390-01605-01 262-440-31 BHATIA RAJESH KUMAR 4 E FUNDERBURG BLVD 4 E FUNDERBURG BLVD MOUNTAIN HOUSE, CA 95391 918.97 100.00 1,018.97 52 390-01691-01 262-390-37 PACHECO YURI 103 E VINCE ST 103 E VINCE ST MOUNTAIN HOUSE, CA 95391 2,141.50 100.00 2,241.50 53 390-01758-01 262-540-53 SANDHU SINGH GURIQBAL 241 E ZINNIA WAY 241 E ZINNIA WAY MOUNTAIN HOUSE, CA 95391 1,523.66 100.00 1,623.66 Item 8.1
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CURRENT PAST

DUE BALANCE
7/16/2026 FEE TOTAL
54 390-01799-01 262-440-41 LIU DENGYU 2274 S STUNHAM LN 1977 LILAC WAY TRACY,CA 95376 1,534.09 100.00 1,634.09 55 390-01801-01 262-390-21 KOTTA SRIDEVI 1652 S CENTRAL PKWY 1652 S CENTRAL PKWY MOUNTAIN HOUSE, CA 95391 1,000.00 100.00 1,100.00 56 390-01825-01 262-440-54 PARAPELLY NAGARANI 2243 S STUNHAM LN 2243 S STUNHAM LN MOUNTAIN HOUSE, CA 95391 1,998.79 100.00 2,098.79 57 390-01847-01 262-520-13 BOLLAPU MAHESWARI 1155 S MORNING GLORY DR 1155 S MORNING GLORY DR MOUNTAIN HOUSE, CA 95391 885.12 100.00 985.12 58 390-01853-01 262-420-37 PEDDISETTI NAGA KIRAN BABU 27 E SALVATORE CT 27 E SALVATORE CT MOUNTAIN HOUSE, CA 95391 1,765.66 100.00 1,865.66 59 390-01889-01 262-460-23 NAGILLA RAMPRASAD REDDY 221 E TUSO RANCH RD 221 E TUSO RANCH RD MOUNTAIN HOUSE, CA 95391 643.68 100.00 743.68 60 390-01898-01 262-470-03 ABBAVARAM REDDY SURENDRA 220 E TUSO RANCH RD 220 E TUSO RANCH RD MOUNTAIN HOUSE, CA 95391 664.38 100.00 764.38 61 390-01930-01 262-480-25 NAIR VIMAL MURALEEDHARAN 113 W PHELPS DR 113 W PHELPS DR MOUNTAIN HOUSE, CA 95391 2,703.12 100.00 2,803.12 62 390-01959-00 262-200-87 KHAN, MOHAMMAD SAEED 1140 S TRADITION ST 1140 S TRADITION ST MOUNTAIN HOUSE, CA 95391 4,577.52 100.00 4,677.52 63 390-02000-01 262-480-11 YASHODARA, RAO 1382 S ANGELOU WAY 8617 LAMBRECHT CT EL CERRITO, CA 94530 1,877.20 100.00 1,977.20 64 390-02108-01 262-420-11 KOLLI RAJASEKHAR 71 E BOSHRA CT 71 E BOSHRA CT MOUNTAIN HOUSE, CA 95391 3,084.14 100.00 3,184.14 65 390-02122-01 262-460-39 SANKARANARAYANAN SAIRAM 297 E CENTRAL PKWY 52 BIGELOW PL SAN RAMON, CA 94583 1,698.36 100.00 1,798.36 66 390-02150-01 262-470-69 GOVERDHANA SHASHIDHAR 281 E CENTRAL PKWY 1556 S OLIVEIRA ST MOUNTAIN HOUSE, CA 95391 1,369.42 100.00 1,469.42 67 390-02160-01 262-510-17 ANSARI ALI AHMED 1230 S ROSS CT 328 FELIPE COMMON FREMONT, CA 94539 1,328.48 100.00 1,428.48 68 390-02251-01 256-54-068 NARAYANAMOORTHY ARAVINDAN 7 W PIAZZA ST 7 W PIAZZA ST MOUNTAIN HOUSE,CA 95391 1,300.00 100.00 1,400.00 69 390-02270-01 262-450-31 BHATLA VIKRAM 132 E RODBELL LN 132 E RODBELL LN MOUNTAIN HOUSE, CA 95391 806.26 100.00 906.26 70 390-02307-01 262-550-44 PERIASAMY MOHANRAJ 50 E CALDER DR 50 E CALDER DR MOUNTAIN HOUSE, CA 95391 3,299.01 100.00 3,399.01 71 390-02564-01 256-570-23 OMAR QUDSIA/FRED 135 W COSTA MESA PL 135 W COSTA MESA PLACE MOUNTAIN HOUSE, CA 95391 2,804.05 100.00 2,904.05 72 390-02567-01 256-570-26 SATHAR ABDUL RAHIM 496 N CHICO LN 496 N CHICO LN MOUNTAIN HOUSE,CA 95391 1,535.00 100.00 1,635.00 73 390-10113-03 254-070-57 ABRAHAM MICHAEL 474 GOODALL ST 474 GOODALL ST MOUNTAIN HOUSE, CA 95391 2,655.25 100.00 2,755.25 74 390-10164-04 254-070-37 THE KOTHAWADE REV TRUST 498 FAULKNER CT 498 FAULKNER CT MOUNTAIN HOUSE, CA 95391 1,385.74 100.00 1,485.74 75 390-10454-01 258-200-10 TAKHAR GURCHARAN 1284 N CAPRI LN 1284 N CAPRI LN MOUNTAIN HOUSE, CA 95391 805.68 100.00 905.68 76 390-10938-00 254-070-77 GAYTAN, DEREK I & DIANA N 440 DANIEL AVE 440 DANIEL AVE MOUNTAIN HOUSE, CA 95391 2,384.48 100.00 2,484.48 77 390-11154-02 254-070-50 DHARMARAJ, SAM 401 FAULKNER ST 36371 FREMONT BLVD FREMONT, CA 94536 2,045.45 100.00 2,145.45 78 390-11677-00 254-070-84 MCWILLIAMS, KATHLEEN 419 E LEGACY DR 419 E LEGACY DR MOUNTAIN HOUSE,CA 95391 2,000.00 100.00 2,100.00 79 390-11899-03 254-190-16 SHAILESH KHATAV 331 COLLINS AVE 7209 OAKRIDGE CT DUBLIN CA 94568 952.45 100.00 1,052.45 80 390-11918-00 254-190-12 DE LEON, LAURA 253 CARROLL CT 253 CARROLL CT MOUNTAIN HOUSE, CA 95391 3,185.98 100.00 3,285.98 81 390-12289-06 254-190-38 KUMAR NAVEEN 368 CARROLL ST 368 CARROLL ST MOUNTAIN HOUSE, CA 95391 2,088.99 100.00 2,188.99 82 390-12622-05 254-200-25 PRASAD SUSHMA 428 S TRADITION ST 428 S TRADITION ST MOUNTAIN HOUSE, CA 95391 903.30 100.00 1,003.30 83 390-12878-02 254-170-06 KEVIN PRASAD 355 STEVEN ST 355 STEVEN ST MOUNTAIN HOUSE, CA 95391 3,192.68 100.00 3,292.68 84 390-13096-02 254-180-18 GEORGE/DORIS KIBLER 122 THOMAS AVE 40 STANTON CT DANVILLE, CA 94506 1,268.40 100.00 1,368.40 85 390-13273-00 254-170-27 CHANDRASHEKAR, SAWMYA 412 GOODWIN ST 412 GOODWIN ST MOUNTAIN HOUSE, CA 95391 818.26 100.00 918.26 86 390-13311-01 256-480-12 MANCHALA RAMU 641 W TRAMONTO DR 641 W TRAMONTO DR MOUNTAIN HOUSE, CA 95391 2,834.65 100.00 2,934.65 87 390-13803-01 254-180-61 FRANKLIN TYRONE/JESSICA 449 GOODWIN ST 449 GOODWIN ST MOUNTAIN HOUSE, CA 95391 3,113.71 100.00 3,213.71 88 390-14206-02 254-150-06 NOMULA SRIDHAR / GREETA 92 E LEGACY DR 92 E LEGACY DR MOUNTAIN HOUSE, CA 95391 2,811.44 100.00 2,911.44 89 390-14445-00 254-150-46 BHULLAR, ANGAD / JAGDEEP 530 LYNN ST 530 LYNN ST MOUNTAIN HOUSE, CA 95391 2,972.66 100.00 3,072.66 90 390-15679-02 254-130-58 SANTHOSH KUMAR NARAYANA PILLAI 61 BRETT AVE 61 BRETT AVE MOUNTAIN HOUSE, CA 95391 1,605.89 100.00 1,705.89 91 390-15842-03 254-140-40 PANAKKAL SINDHU HARI 101 BRYANT AVE 6357 COTTLE RD SAN JOSE, CA 95123 907.10 100.00 1,007.10 92 390-15853-00 254-140-42 COOK, YVETTE 79 BRYANT AVE 79 BRYANT AVE MOUNTAIN HOUSE, CA 95391 947.55 100.00 1,047.55 93 390-15862-01 254-140-45 HUANG HUI WEN 55 BRYANT AVE 55 BRYANT AVE MOUNTAIN HOUSE, CA 95391 1,102.08 100.00 1,202.08 94 390-16619-02 254-120-04 SHARMA SALONI 816 SAMANTHA ST 816 SAMANTHA ST MOUNTAIN HOUSE, CA 95391 3,610.69 100.00 3,710.69 95 390-16625-06 254-120-02 SABBIR AHMED/KANEEZ F TUMPA 784 SAMANTHA ST 3215 ALVORD WAY PLEASANTON, CA 94588 1,973.55 100.00 2,073.55 96 390-16694-02 254-110-37 DONAL LEON ESCOBAR 701 JOSEPH ST 2050 MCKEE RD APT 49 SAN JOSE, CA 95116 4,762.03 100.00 4,862.03 97 390-16805-01 254-110-36 NGUYEN TRUNG 709 JOSEPH ST 709 JOSEPH ST MOUNTAIN HOUSE, CA 95391 2,752.50 100.00 2,852.50 98 390-17089-02 254-110-28 JANGID JAGDISH 308 NICOLE AVE 308 NICOLE AVE MOUNTAIN HOUSE, CA 95391 3,413.71 100.00 3,513.71 99 390-17244-00 254-110-51 FIGUEROA DOMINGO JR & MARIA 674 TRADITION ST 674 TRADITION ST MOUNTAIN HOUSE, CA 95391 999.16 100.00 1,099.16 100 390-17937-00 254-090-23 LAU AMY HING LING 715 SHELLI ST 11735 BIG CANYON LN SAN DIEGO CA 92131 953.12 100.00 1,053.12 101 390-18768-05 254-090-61 AZAD FARID 546 HUTCHINGS WAY 546 HUTCHINGS WAY MOUNTAIN HOUSE, CA 95391 967.24 100.00 1,067.24 102 390-19134-01 254-100-57 NARAYANASWAMY RAMAKRISHNAN 541 SULLIVAN WAY 541 SULLIVAN WAY MOUNTAIN HOUSE, CA 95391 2,396.42 100.00 2,496.42 103 390-19139-00 254-100-56 ELIZONDO FRANCISCO J & VERONICA 549 SULLIVAN WAY 549 SULLIVAN WAY MOUNTAIN HOUSE,CA 95391 1,097.49 100.00 1,197.49 104 390-19153-00 254-100-10 LEGASPI, JASON 830 SHELLI ST 830 SHELLI ST MOUNTAIN HOUSE, CA 95391 1,504.40 100.00 1,604.40 105 390-19344-02 254-100-04 SARDAR, HAROON 799 ELLERBROOK ST 799 ELLERBROOK ST MOUNTAIN HOUSE, CA 95391 1,583.82 100.00 1,683.82 106 390-19518-00 254-220-23 MITCHELL, NORRIS / TRACI 310 CENTRAL PARKWAY 310 CENTRAL PARKWAY MOUNTAIN HOUSE, CA 95391 658.81 100.00 758.81 Item 8.1
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CURRENT PAST

DUE BALANCE
7/16/2026 FEE TOTAL
107 390-19568-00 254-220-14 SHANNON MEYER / EKKASITH PHIXI 444 CENTRAL PARKWAY 444 CENTRAL PARKWAY MOUNTAIN HOUSE, CA 95391 2,146.47 100.00 2,246.47 108 390-19944-00 254-210-10 NGUYEN HANNAH KHUE 718 CENTRAL PARKWAY 3713 PEMBERTON WAY HIGHPOINT NC 27265-8053 4,380.48 100.00 4,480.48 109 390-19957-00 254-210-08 BURCH, CYNTHIA D. 736 CENTRAL PARKWAY 736 CENTRAL PARKWAY MOUNTAIN HOUSE, CA 95391 940.89 100.00 1,040.89 110 390-20307-05 254-360-02 WUNNAVA KAYLAN 75 W ADMIRABLE LN 707 BARLETA CT LIVERMORE, CA 94550 840.26 100.00 940.26 111 390-20378-03 254-350-01 AHMADZA , SHAFIQ AHMAD 40 W ATENTO LN 40 W ATENTO LN MOUNTAIN HOUSE, CA 95391 2,568.26 100.00 2,668.26 112 390-20568-03 254-340-01 SHIH PIN-JUNG 16 W BELLEZA LN 5601 ARNOLD RD #110 DUBLIN, CA 94569 1,931.57 100.00 2,031.57 113 390-20938-00 254-370-43 TEJEDA, HECTOR NEL 261 W GALLO WAY 261 W GALLO WAY MOUNTAIN HOUSE, CA 95391 800.00 100.00 900.00 114 390-21504-03 254-340-16 TSAN DAVID 110 W INVITAR LN 110 W INVITAR LN MOUNTAIN HOUSE, CA 95391 3,214.32 100.00 3,314.32 115 390-21525-01 254-340-19 MAGBANUA REUBEN/ALEXIS 148 W INVITAR LN 148 W INVITAR LN MOUNTAIN HOUSE, CA 95391 786.69 100.00 886.69 116 390-21925-00 254-320-08 SHELTON TANYA D 21 W AMENO LN 21 W AMENO LN MOUNTAIN HOUSE, CA 95391 1,006.39 100.00 1,106.39 117 390-22121-02 254-330-24 ASHOK K/SONIA GOYAL 102 W CASITA LN 5255 STEVENS CREEK BLVD #275 SANTA CLARA, CA 95051 667.38 100.00 767.38 118 390-22703-00 254-310-04 BRADLEY CHUN / MELINDA SALAZAR 204 W HERITAGE DR 204 W HERITAGE DR MOUNTAIN HOUSE, CA 95391 2,285.33 100.00 2,385.33 119 390-22760-00 254-300-38 LI WENHUI & YE SHENGCHUN 420 W HERITAGE DR 2106 PALMER DR PLEASANTON CA 94588 1,748.49 100.00 1,848.49 120 390-22770-00 254-300-36 LI, XIANGFE 468 W HERITAGE DR 468 W HERITAGE DR MOUNTAIN HOUSE, CA 95391 1,606.35 100.00 1,706.35 121 390-23045-00 254-310-10 ESSALOU, NANSI 286 W VERANO WAY 286 W VERANO WAY MOUNTAIN HOUSE, CA 95391 3,433.51 100.00 3,533.51 122 390-23241-00 254-300-08 WATTS, HORTENSIA 509 W RECREO WAY 509 W RECREO WAY MOUNTAIN HOUSE, CA 95391 2,696.74 100.00 2,796.74 123 390-24147-00 254-260-02 DHILLON, HARJINDER 52 W FAUNA CT 52 W FAUNA CT MOUNTAIN HOUSE, CA 95391 2,092.66 100.00 2,192.66 124 390-24333-01 254-290-30 JOHN REUBEN S & PALACHUVATIL SHEENA V 512 W FAUNA AVE 642 N SAN MARCOS DR MOUNTAIN HOUSE, CA 95391 1,012.56 100.00 1,112.56 125 390-24512-05 254-280-19 GRACE XIE 627 W CONEJO AVE 627 W CONEJO AVE MOUNTAIN HOUSE, CA 95391 956.55 100.00 1,056.55 126 390-24967-03 254-250-49 YOUNG KIYOKO 820 S LISTA ST 3281 BARONS LN SAN RAMON, CA 94582 2,147.35 100.00 2,247.35 127 390-24972-03 254-250-48 NIVARTHI PHANI 842 S LISTA ST 842 S LISTA ST MOUNTAIN HOUSE, CA 95391 2,419.99 100.00 2,519.99 128 390-25318-02 254-290-14 FONG MARK/ MEI 526 W CONEJO AVE 49 E 10TH STREET SUITE A TRACY CA 95376 2,727.11 100.00 2,827.11 129 390-25536-01 254-270-20 NAG BISHWAJIT 855 S AMOR ST 855 S AMOR ST MOUNTAIN HOUSE, CA 95391 4,355.60 100.00 4,455.60 130 390-25595-00 254-270-29 ORLANDI JAMES 862 S AMOR ST 862 S AMOR ST MOUNTAIN HOUSE, CA 95391 600.59 100.00 700.59 131 390-25797-01 254-280-13 CHEN TONGOING/LI 631 W PRIVADO WAY 631 W PRIVADO WAY MOUNTAIN HOUSE, CA 95391 981.18 100.00 1,081.18 132 390-26781-04 254-420-09 THOMAS ROBY 31 S CABALLO ST 31 S CABALLO ST MOUNTAIN HOUSE, CA 95391 1,756.94 100.00 1,856.94 133 390-27115-00 254-420-27 VALDEZ, JESSIE 573 W VIENTO ST 573 W VIENTO ST MOUNTAIN HOUSE, CA 95391 1,099.78 100.00 1,199.78 134 390-27317-04 254-430-19 LUM PING 189 S VISTA HERMOSA ST 1256 CREIGHTON CT MILPITAS, CA 95035 4,222.60 100.00 4,322.60 135 390-27379-01 254-430-27 BASU GOURAB 262 S CABALLO ST 262 S CABALLO ST MOUNTAIN HOUSE, CA 95391 1,134.98 100.00 1,234.98 136 390-29058-04 254-380-16 ILAHA NAWAZ/SIDDIQ ZUHRA 28 S TRANQUILIDAD CT 28 S TRANQUILIDAD CT MOUNTAIN HOUSE,CA 95391 2,289.04 100.00 2,389.04 137 390-29220-01 254-380-03 VANGAPALLI, RAVINDRA KUMAR 17 S ALDEA ST 17 S ALDEA ST MOUNTAIN HOUSE, CA 95391 751.65 100.00 851.65 138 390-29853-01 254-400-37 KARUPPIAH, KANNAN 476 W VIENTO ST 476 W VIENTO ST MOUNTAIN HOUSE, CA 95391 3,648.78 100.00 3,748.78 139 390-30862-00 256-090-24 WRIGHT, JUSTIN 149 N ESTES WAY 149 N ESTES WAY MOUNTAIN HOUSE, CA 95391 3,319.76 100.00 3,419.76 140 390-31035-01 256-090-04 ULLAL, VIJAY 190 N LAFAYETTE ST 19384 CHABLIS CT SARATOGA CA 95070 1,302.04 100.00 1,402.04 141 390-31475-01 256-160-43 BAMIDELE SUNDAY/FLORENCE 73 N BOYLE HEIGHTS CT 73 N BOYLE HEIGHTS CT MOUNTAIN HOUSE, CA 95391 1,383.42 100.00 1,483.42 142 390-31671-00 256-210-16 SERMENO MIANNA 50 N ALTA DENA STREET 2455 NAGLEE RD STE 200 TRACY, CA 95304 1,426.76 100.00 1,526.76 143 390-31709-03 256-210-40 MANDALI LEELAKRISHNA 634 W LA CANADA AVE 634 W LA CANADA AVE MOUNTAIN HOUSE, CA 95391 1,288.72 100.00 1,388.72 144 390-31716-00 256-230-30 BOLUSAN, JENNIFER / ERIK 650 W LA CANADA AVE 650 W LA CANADA AVE MOUNTAIN HOUSE, CA 95391 3,315.30 100.00 3,415.30 145 390-31777-01 256-220-38 CUELLAR, ROBERTO 125 N MENLO PARK ST 125 N MENLO PARK ST MOUNTAIN HOUSE, CA 95391 511.15 100.00 611.15 146 390-32195-01 256-200-33 LEON JOSE EMILLIO ESCOBAR 176 N SIERRA MADRE ST 176 N SIERRA MADRE ST MOUNTAIN HOUSE, CA 95391 1,643.41 100.00 1,743.41 147 390-32520-00 256-200-28 BURGUENO CAROLYN 205 N ALTA DENA ST 205 N ALTA DENA ST MOUNTAIN HOUSE, CA 95391 2,382.86 100.00 2,482.86 148 390-32561-01 256-200-13 SEBBAH SAMIR 565 W ALAMEDA DR 565 W ALAMEDA DR MOUNTAIN HOUSE, CA 95391 946.55 100.00 1,046.55 149 390-32931-00 256-080-01 PINEDA, FLORENCIO S & PACIENCIA V 258 W ARCADIA ST 258 W ARCADIA ST MOUNTAIN HOUSE, CA 95391 1,935.30 100.00 2,035.30 150 390-32946-02 256-080-05 WOODARD JR., FRED E. 248 N VENTURA ST 248 N VENTURA ST MOUNTAIN HOUSE, CA 95391 672.38 100.00 772.38 151 390-33791-00 256-180-42 WILKINS, LESLIE 409 N ALTA DENA ST 409 N ALTA DENA ST MOUNTAIN HOUSE, CA 95391 1,055.18 100.00 1,155.18 152 390-33926-00 256-170-26 WAZERI WAID 470 N PALO ALTO ST 470 N PALO ALTO ST MOUNTAIN HOUSE, CA 95391 1,513.53 100.00 1,613.53 153 390-34148-00 256-180-28 KHAN, NOORULLAH 379 N SIERRA MADRE ST 379 N SIERRA MADRE ST MOUNTAIN HOUSE, CA 95391 2,498.64 100.00 2,598.64 154 390-34174-01 256-180-35 VARGAS CASSIE 440 N SIERRA MADRE ST 440 N SIERRA MADRE ST MOUNTAIN HOUSE, CA 95391 1,868.55 100.00 1,968.55 155 390-34381-01 256-110-43 SIMONPAUL ARUN BASKAR 436 N MONTEBELLO ST 436 N MONTEBELLO ST MOUNTAIN HOUSE, CA 95391 543.57 100.00 643.57 156 390-35621-01 256-110-27 GORUGANTHU, VAMSEE/BINDU 446 N ALBANY ST 446 N ALBANY ST MOUNTAIN HOUSE, CA 95391 841.26 100.00 941.26 157 390-35861-00 256-030-15 AHMED TALHA 480 N ORINDA CT 480 N ORINDA CT MOUNTAIN HOUSE, CA 95391 837.26 100.00 937.26 158 390-35894-00 256-020-45 JONES LATISHA 445 N LAFAYETTE CT 445 N LAFAYETTE CT MOUNTAIN HOUSE, CA 95391 989.54 100.00 1,089.54 159 390-36238-04 256-020-03 OLSON IVAN/OLSON SUSAN 483 N ESTES WAY 2418 PINEHURST CT DISCOVERY BAY, CA 94505 2,124.96 100.00 2,224.96 Item 8.1
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CURRENT PAST

DUE BALANCE
7/16/2026 FEE TOTAL
160 390-36294-01 256-420-22 ALLAHBAKASH FHAROSE 811 N PLUMAS DR 811 N PLUMAS DR MOUNTAIN HOUSE, CA 95391 2,683.42 100.00 2,783.42 161 390-36462-02 256-270-51 JAMBE SURENDRA/SHEWALE RUPA 651 N ANDALUSIA WY 651 N ANDALUSIA WY MOUNTAIN HOUSE, CA 95391 811.26 100.00 911.26 162 390-36465-00 256-270-52 CAREY, DUANE 679 N ANDALUSIA WY 679 N ANDALUSIA WY MOUNTAIN HOUSE, CA 95391 3,290.64 100.00 3,390.64 163 390-36845-00 256-360-24 FITCH, SONNY 511 W QUESTA TRAIL 511 W QUESTA TRAIL MOUNTAIN HOUSE, CA 95391 4,060.51 100.00 4,160.51 164 390-37214-01 256-430-21 THIRUMALAI PARTHASARATHY 862 N BRAMASOLE AV 608 FESTIVO COURT FREMONT, CA 94539 3,251.43 100.00 3,351.43 165 390-37216-00 256-430-22 PADOJINO, RESTY / ANNA LYN 874 N BRAMASOLE AV 874 N BRAMASOLE AV MOUNTAIN HOUSE, CA 95391 5,516.29 100.00 5,616.29 166 390-37245-01 256-350-36 KUMAR ANIL/KAVITA 534 W CAMPANIA WY 44426 CAVISSON CT FREMONT CA 94539 1,907.75 100.00 2,007.75 167 390-37408-02 256-470-48 MAKHIJA, APNEET 702 N SAN MARCOS DR 5055 CERRETO ST DUBLIN, CA 94568 1,859.92 100.00 1,959.92 168 390-37463-01 256-470-05 MISHRA GOPI 675 W ESPLANADE DR 675 W ESPLANADE DR MOUNTAIN HOUSE, CA 95391 840.26 100.00 940.26 169 390-50095-02 254-240-27 SAURABH KUMAR KULKURNI/ DIVYA 246 W RECREO WAY 246 W RECREO WAY MOUNTAIN HOUSE, CA 95391 841.26 100.00 941.26 170 390-50669-05 256-150-34 JAIN SUJAN 405 W ALAMEDA DR PO BOX 320835 LOS GATOS,CA 95032 1,700.48 100.00 1,800.48 171 390-51814-01 256-290-54 SULLIVAN MARK KENYA 162 W QUESTA TRAIL 162 W QUESTA TRAIL MOUNTAIN HOUSE, CA 95391 1,396.74 100.00 1,496.74 172 390-56460-02 256-120-06 SARWAR, HOMA/ABDULKARIM 355 W CUPERTINO AVE 355 W CUPERTINO AVE MOUNTAIN HOUSE, CA 95391 846.26 100.00 946.26 173 390-58142-04 254-350-12 YUANBIN GUO/XINMEL XIE 92 W POSADA LN 562 N MONTEBELLO ST MOUNTAIN HOUSE, CA 95391 1,034.67 100.00 1,134.67 174 390-59961-01 254-130-08 ALAM MOHAMMAD 726 CORINNE ST 1343 S HART DR MOUNTAIN HOUSE,CA 95391 983.80 100.00 1,083.80 175 390-60006-00 256-130-17 TOLBERT, CARNELL 344 W MORAGA ST 344 W MORAGA ST MOUNTAIN HOUSE, CA 95391 1,559.88 100.00 1,659.88 176 390-60140-01 254-370-08 ZHOU XIAOWEN/ LIHUA 145 W PROSPERIDAD WAY 145 W PROSPERIDAD WAY MOUNTAIN HOUSE, CA 95391 810.26 100.00 910.26 177 390-60146-00 256-220-12 BOLLU RAMAKRISHNA & PULICHERLA SREEVEENA 698 W GLENDORA AVE 698 W GLENDORA AVE MOUNTAIN HOUSE, CA 95391 966.56 100.00 1,066.56 178 390-60314-00 254-460-30 LEVY BERYL 674 W SOMBRA WAY 674 W SOMBRA WAY MOUNTAIN HOUSE, CA 95391 589.47 100.00 689.47 179 390-60369-03 256-280-04 YANAMANDRA LALITA 120 W DEL PRADO CT 120 W DEL PRADO CT MOUNTAIN HOUSE, CA 95391 1,488.54 100.00 1,588.54 180 390-60777-03 256-080-50 DEORA AJIT/SUCHETA 233 N LAFAYETTE ST 45365 RUTHERFORD TERRACE FREMONT, CA 94539 2,894.66 100.00 2,994.66 181 390-61012-01 256-120-01 PARAB, AVINASH/ROHINI 391 W CUPERTINO AVE 8121 OXBOW LANDING LOOP ROSEVILLE, CA 95747 1,297.62 100.00 1,397.62 182 390-61064-00 254-090-37 GAPOL, RON 645 PROSPERITY ST 645 PROSPERITY ST MOUNTAIN HOUSE, CA 95391 1,567.59 100.00 1,667.59 183 390-61193-03 254-250-01 GUNDAPANENI KEERTHI 254 W CAMARADA AVE 449 PROVIDENCE ST MOUNTAIN HOUSE, CA 95391 3,052.57 100.00 3,152.57 184 390-61485-02 254-420-31 JAGDEEP SINGH/ NAVPREET PADDA 502 W VIENTO ST 79 ADAIR WAY HAYWARD, CA 94542 4,508.31 100.00 4,608.31 185 390-61491-02 254-390-38 DILBAG SINGH/RAJINDER KAUR 195 S TRANQUILIDAD ST 195 S TRANQUILIDAD ST MOUNTAIN HOUSE, CA 95391 817.16 100.00 917.16 186 390-61528-00 256-290-48 ANDERSON TRINA 708 N ORTEGA DR 708 N ORTEGA DR MOUNTAIN HOUSE, CA 95391 1,005.93 100.00 1,105.93 187 390-61575-00 256-290-08 VARGAS WANA 670 N MUSEO DR 670 N MUSEO DR MOUNTAIN HOUSE, CA 95391 589.27 100.00 689.27 188 390-62024-00 254-280-33 LIAO, HUA AND GUANG S 615 W FAUNA AVE 4722 MOORPARK AVE SAN JOSE CA 95129 4,894.67 100.00 4,994.67 189 390-62124-02 256-230-16 BISHWAJIT NAG 715 W LA CANADA AVE 4579 MARTIN ST UNION CITY, CA 94587 743.98 100.00 843.98 190 390-62312-01 258-250-25 KUMAR, GULSHAN 1370 N DRAGO WAY 1370 N DRAGO WAY MOUNTAIN HOUSE, CA 95391 2,912.81 100.00 3,012.81 191 390-62324-01 256-300-68 DEVALLA GOPALA KRISHNA 316 W PORTALES DR 316 W PORTALES DR MOUNTAIN HOUSE, CA 95391 1,438.96 100.00 1,538.96 192 390-62836-05 254-350-05 SWAROOP RAGHUNATHA/LALITHA 97 W POSADA LN 952 CAMERON CIR MILPITAS, CA 95035 3,736.74 100.00 3,836.74 193 390-62837-07 256-350-55 JAIN ANURANG/DEEPA 521 W BONAVENTURE AVE 43565 EUCLID DR FREMONT, CA 94539 2,160.48 100.00 2,260.48 194 390-62839-03 254-300-18 SANTOSH CHUNDI 528 W VERANO WAY PO BOX 11721 PLEASANTON, CA 94588 1,494.83 100.00 1,594.83 195 390-63009-00 256-420-03 KWAN, MICHAEL & SABRINA 717 W ANTIGUA TERRACE 717 W ANTIGUA TERRACE MOUNTAIN HOUSE, CA 95391 3,708.06 100.00 3,808.06 196 390-63015-00 254-150-62 HUANG, SHIH YU & WEN CHIH 65 ALEXANDRIA DR 465 CLAUSER DR MILPITAS CA 95035 575.25 100.00 675.25 197 390-63017-05 256-160-36 DHANWANTRI, RUCHIKA 8 N BOYLE HEIGHTS CT 8 N BOYLE HEIGHTS CT MOUNTAIN HOUSE, CA 95391 826.26 100.00 926.26 198 390-63025-01 256-300-49 KANAKI SHRINIVAS 281 W SANTA CLARA DR 281 W SANTA CLARA DR MOUNTAIN HOUSE, CA 95391 1,088.00 100.00 1,188.00 199 390-63102-02 256-030-36 SANDHU SEAN 285 W MORAGA ST 285 W MORAGA ST MOUNTAIN HOUSE, CA 95391 2,075.12 100.00 2,175.12 200 390-63106-03 256-030-42 NAGESWARA VENIGALLA/H MAROUTHU 442 N VENTURA ST 43127 WASHINGTON CMN FREMONT, CA 94539 813.26 100.00 913.26 201 390-63127-01 256-440-25 SINGH, RAJEEV K/SHALINI 780 N PLUMAS DR 780 N PLUMAS DR MOUNTAIN HOUSE, CA 95391 2,891.47 100.00 2,991.47 202 390-63131-03 256-300-25 PATAKOTA PRABHAKARA 306 W SANTA CLARA DR 33 DAVID ST CAHOKIA, IL 62206 3,582.82 100.00 3,682.82 203 390-63135-05 256-300-29 HUAI JESSICA JIE 322 W SANTA CLARA DR 20820 CANYON VIEW DR SARATOGA, CA 95070 4,802.96 100.00 4,902.96 204 390-63154-07 256-080-43 SOOD, RAMESH 161 N LAFAYETTE ST 7183 FAWN HILLS PLEASANTON CA 94566 1,971.97 100.00 2,071.97 205 390-63167-01 256-300-57 MCLEOD HA/HARRY 260 W PORTALES DR 3928 PINE LAKE CIR STOCKTON, CA 95219 2,275.02 100.00 2,375.02 206 390-63175-03 254-180-05 HEARNE, KENNETH R 53 E LEGACY DR PO BOX 19688 STANFORD, CA 94309 3,800.80 100.00 3,900.80 207 390-63192-01 256-060-03 CHIUAH, HONG L & XIAOJIE SHAO 234 W SANTA CRUZ WAY 4149 EL CAMINO WAY #E PALO ALTO CA 94306 1,261.22 100.00 1,361.22 208 390-63197-02 254-080-52 UBHRANI MANJU 683 FARRINGTON ST 683 FARRINGTON ST MOUNTAIN HOUSE, CA 95391 2,954.70 100.00 3,054.70 209 390-63305-02 254-350-18 VENKATA PULUGURTA 175 W INVITAR LN 3124 BRITTAN AVE SAN CARLOS, CA 94070 1,013.55 100.00 1,113.55 210 390-63401-03 254-250-03 RYAN J GALANG 282 W CAMARADA AVE 1145 PALOMAR CT TRACY, CA 95391 1,674.57 100.00 1,774.57 211 390-63422-01 256-060-37 ISABEL ELIZABETH 221 W ARCADIA ST 221 W ARCADIA ST MOUNTAIN HOUSE, CA 95391 822.48 100.00 922.48 212 390-63433-00 256-350-56 CHRISTOPHER WAI CHEUNG & OI LAU 533 W BONAVENTURE AVE PO BOX 613133 SAN JOSE CA 95161 2,480.20 100.00 2,580.20 Item 8.1
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CURRENT PAST

DUE BALANCE
7/16/2026 FEE TOTAL
213 390-63503-02 256-480-16 KIM JOHN/SUN Y 591 W TRAMONTO DR 9 WALDORF IRVINE, CA 92612 812.25 100.00 912.25 214 390-63519-00 254-110-17 HAQ, MUHAMMED 322 ANTHONY AVE 322 ANTHONY AVE MOUNTAIN HOUSE, CA 95391 819.62 100.00 919.62 215 390-63528-01 254-430-07 YUSUFI SAHAR 511 W LAS BRISAS DR 511 W LAS BRISAS DR MOUNTAIN HOUSE, CA 95391 3,073.08 100.00 3,173.08 216 390-63617-02 256-060-35 ANN PUTHIYADAM 233 W ARCADIA ST 2378 CRESTHAVEN ST MILPITAS, CA 95035 833.26 100.00 933.26 217 390-63631-00 254-100-31 MUHIB, ABRAR 831 PROSPERITY ST 831 PROSPERITY ST MOUNTAIN HOUSE, CA 95391 1,070.58 100.00 1,170.58 218 390-63653-02 256-340-21 MADHAPPAN ESWARI 182 W ALCALA CT 182 W ALCALA CT MOUNTAIN HOUSE, CA 95391 3,677.53 100.00 3,777.53 219 390-63811-02 256-070-12 GONUGUNTLA MARUTHI PRASAD 277 W SAINT FRANCIS AVE 277 W SAINT FRANCIS AVE MOUNTAIN HOUSE, CA 95391 3,025.57 100.00 3,125.57 220 390-63865-01 256-370-11 ALEXANDER-WASHINGTON, LORI 790 N QUESTA CT 790 N QUESTA CT MOUNTAIN HOUSE, CA 95391 3,951.92 100.00 4,051.92 221 390-63867-01 256-370-12 DAHIYA, SWETA/SHARMA SURYADEV 791 N MARQUIS WAY 791 N MARQUIS WAY MOUNTAIN HOUSE, CA 95391 3,220.75 100.00 3,320.75 222 390-63871-02 256-340-14 SINGH INDERJEET/KAUR SARBJEET 179 W ALCALA CT 179 W ALCALA CT MOUNTAIN HOUSE, CA 95391 3,699.05 100.00 3,799.05 223 390-63881-02 256-440-12 BHUSHAN HIMANSHU 717 N SAN MARCOS DR 717 N SAN MARCOS DR MOUNTAIN HOUSE, CA 95391 1,690.45 100.00 1,790.45 224 390-63909-06 256-490-01 ANURAG/DEEPA JAIN 725 N SANTA INEZ DR 43565 EUCLID DR FREMONT, CA 94539 827.89 100.00 927.89 225 390-63932-01 256-340-07 TALERICO, CHRISTOPHER/SARAH 287 W ALCALA AVE 287 W ALCALA AVE MOUNTAIN HOUSE, CA 95391 2,680.00 100.00 2,780.00 226 390-63942-02 256-380-44 AYON DATTA 410 W SAN JUAN DR 410 W SAN JUAN DR MOUNTAIN HOUSE, CA 95391 1,034.89 100.00 1,134.89 227 390-63956-03 256-440-08 THEVARKANDY AJMAL SONITH 743 N SAN MARCOS DR 743 N SAN MARCOS DR MOUNTAIN HOUSE, CA 95391 2,870.45 100.00 2,970.45 228 390-63962-01 256-440-33 ABDELMALAK, HANY 775 W PLUMAS CT 775 W PLUMAS CT MOUNTAIN HOUSE, CA 95391 880.78 100.00 980.78 229 390-63970-02 256-380-37 KUPPAN KARTHIKEYAN 419 W SAN JUAN DR 419 W SAN JUAN DR MOUNTAIN HOUSE, CA 95391 865.52 100.00 965.52 230 390-63983-04 256-310-18 NAUMAN MUSTAFA/TEHREEMSIDDIQUI 373 W TUSCAN LN 48949 AIR FERN CMN FREMONT, CA 94593 1,244.48 100.00 1,344.48 231 390-63987-03 256-310-46 MUHAMMAD MOZAFFAR/ZEHRA 378 W ABBEY LN 2904 BENCHMARK DR PLANO, TX 75023 1,114.01 100.00 1,214.01 232 390-64039-03 256-320-39 YU-TING CHEN/STEPHANIE CHEN 703 N MUSEO DR 4076 KINSDALE STREET DUBLIN, CA 94568 4,280.56 100.00 4,380.56 233 390-64064-01 256-440-02 ALEX, BOBY/VARGHESE, ELIZABETH 783 N SAN MARCOS DR 783 N SAN MARCOS DR MOUNTAIN HOUSE, CA 95391 2,475.58 100.00 2,575.58 234 390-64122-01 262-070-25 SURYADEVARA, JAGADISH 972 S SHIELDS AVE 972 S SHIELDS AVE MOUNTAIN HOUSE, CA 95391 566.11 100.00 666.11 235 390-64148-03 256-370-51 SAMER KIRESH 439 W AVENTINO AVE 4055 18TH ST SAN FRANCISCO, CA 94114 966.55 100.00 1,066.55 236 390-64151-03 262-100-07 KRISHNAKANTH/RAJITHA BATTA 1187 S IRVINE ST 691 N CAPITOL AVE - UNIT 3 SAN JOSE, CA 95133 1,469.26 100.00 1,569.26 237 390-64184-01 256-370-28 DHINAKARAN KARTHIKEYAN 402 W AVENTINO AVE 402 W AVENTINO AVE MOUNTAIN HOUSE, CA 95391 706.74 100.00 806.74 238 390-64193-02 256-250-02 VELAGAPUDI JAY 551 N CASTELLINA TERRACE 551 N CASTELLINA TERRACE MOUNTAIN HOUSE, CA 95391 5,510.48 100.00 5,610.48 239 390-64208-06 256-440-53 HONG YUAN/QINGZHONG JIAO 767 W RIATTA RANCH DR 41556 ERMA AVE FREMONT, CA 94539 1,295.18 100.00 1,395.18 240 390-64260-03 262-050-05 DONTHULA VENUBABU 936 S BLAKE ST 936 S BLAKE ST MOUNTAIN HOUSE, CA 95391 1,425.22 100.00 1,525.22 241 390-64397-02 262-100-22 KONDALAM SATISH PIDAPARTI SAMH 156 W BONNER DR 387 LOS COCHES ST MILPITAS CA 95035 634.15 100.00 734.15 242 390-64401-01 262-100-28 GIBSON, JACK 107 W LADD DR 107 W LADD DR MOUNTAIN HOUSE, CA 95391 2,541.86 100.00 2,641.86 243 390-64472-05 262-090-03 CAITLIN N ARENDS 276 W ALDRICH PL 736 MADISON AVE #2 REDWOOD CITY, CA 94061 1,049.96 100.00 1,149.96 244 390-64483-02 262-170-28 MOHAMMED SHAFAATUDDIN AHMED 1174 S VECINDAD ST 1174 S VECINDAD ST MOUNTAIN HOUSE, CA 95391 4,112.16 100.00 4,212.16 245 390-64507-04 262-060-26 KROVVIDI RAVI/GAYATHRI G 1085 S FOWLER LN 3913 WOODFORD DR SAN JOSE, CA 95124 1,863.02 100.00 1,963.02 246 390-64513-01 262-090-15 ANTONIO THYRONE/MERCEDES 158 W ALDRICH PL 158 W ALDRICH PL MOUNTAIN HOUSE, CA 95391 4,670.81 100.00 4,770.81 247 390-64540-02 262.040.02 FAHEEMUDDIN, MOHAMMAD 1034 S VECINDAD ST 1034 S VECINDAD ST MOUNTAIN HOUSE,CA 95391 2,132.34 100.00 2,232.34 248 390-64574-01 262-060-19 SONG ZIXIAO 1005 S FOWLER LN 1005 S FOWLER LN MOUNTAIN HOUSE, CA 95391 1,379.74 100.00 1,479.74 249 390-64613-01 262-140-33 THAVAMANI KARTHIK 611 W STRAUSS DR 611 W STRAUSS DR MOUNTAIN HOUSE, CA 95391 942.55 100.00 1,042.55 250 390-64630-03 262-110-32 MURTI, PRADEEP 162 W FREMONT DR 4532 ALTA TERRARD DUBLIN CA 94568 897.04 100.00 997.04 251 390-64662-01 262-140-29 KHANDELWAL RUPESH 1015 S JACOBS DR 1015 S JACOBS DR MOUNTAIN HOUSE, CA 95391 3,887.07 100.00 3,987.07 252 390-64680-03 262-140-59 MUKHERJEE SAMYO/TULIKA 1021 S VECINDAD ST 34288 MULBERRY TERRACE FREMONT, CA 94555 834.58 100.00 934.58 253 390-64713-01 262-120-02 RODRIGUEZ CARLOS/MARIBEL 147 W HAYWARD LN 147 W HAYWARD LN MOUNTAIN HOUSE, CA 95391 3,607.53 100.00 3,707.53 254 390-64730-01 262-170-07 PADMANABAN NAPOLEON 1279 S OLSON AVE 1279 S OLSON AVE MOUNTAIN HOUSE, CA 95391 855.26 100.00 955.26 255 390-64748-05 262-120-10 ANVEKAR SACHIN/VERNEKAR VIJETH 220 W HAYWARD LN 38988 SAILFISH COMMON FREMONT CA 94536 3,339.33 100.00 3,439.33 256 390-64834-01 262-140-15 SUBRAMANIAN THENMOZHI 589 W HUNTINGTON AVE 589 W HUNTINGTON AVE MOUNTAIN HOUSE, CA 95391 694.06 100.00 794.06 257 390-64865-02 262-140-07 SUBBARAO VIJENDRA 1009 S ATWOOD LN 1009 S ATWOOD LN MOUNTAIN HOUSE, CA 95391 3,822.93 100.00 3,922.93 258 390-64873-01 262-130-01 PAYUMO PAUL/DAWN 957 S ATWOOD LN 957 S ATWOOD LN MOUNTAIN HOUSE, CA 95391 3,895.92 100.00 3,995.92 259 390-64928-01 262-130-17 DEB SHUBHASIS 927 S TUPPER CT 927 S TUPPER CT MOUNTAIN HOUSE, CA 95391 1,049.21 100.00 1,149.21 260 390-64956-01 262-280-25 MALLU SRIKANTH 1378 S DAIRY DR 1378 S DAIRY DR MOUNTAIN HOUSE, CA 95391 3,860.48 100.00 3,960.48 261 390-64970-01 262-230-76 YU QIHUA 1417 S PROSPERITY ST 1417 S PROSPERITY ST MOUNTAIN HOUSE, CA 95391 937.96 100.00 1,037.96 262 390-64979-03 262-150-24 MARINGANTI HARIKRISHNA 1095 S DANA CT 1095 S DANA CT MOUNTAIN HOUSE, CA 95391 4,053.87 100.00 4,153.87 263 390-65008-04 262-180-67 MORTHALA LAKSHMA REDDY 564 E MARCELLO AVE 3279 N TALBOT DR LATHROP CA 95330 2,224.96 100.00 2,324.96 264 390-65071-01 262-200-13 SHARMA SRISHTI 1029 S MODENA ST 1029 S MODENA ST MOUNTAIN HOUSE, CA 95391 758.40 100.00 858.40 265 390-65135-01 256-580-27 SHELKE, JAYANT 36 W FERNDALE PL 36 W FERNDALE PL MOUNTAIN HOUSE, CA 95391 1,640.18 100.00 1,740.18 Item 8.1
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CURRENT PAST

DUE BALANCE
7/16/2026 FEE TOTAL
266 390-92504-00 256-270-41 MCQUEEN, KARYN 738 N DEL PRADO ST 738 N DEL PRADO ST MOUNTAIN HOUSE, CA 95391 3,371.14 100.00 3,471.14 267 390-94071-03 254-430-01 CHRISTIAN JAYDEEP 157 S PUENTE DR 157 S PUENTE DR MOUNTAIN HOUSE, CA 95391 1,598.31 100.00 1,698.31 268 390-95874-03 256-130-03 HARI SINDHU 470 W MORAGA ST 6357 COTTLE RD SAN JOSE, CA 95123 737.79 100.00 837.79 269 390-95991-01 256-350-61 BASHA FAREEDH 593 W BONAVENTURE AVE 593 W BONAVENTURE AVE MOUNTAIN HOUSE, CA 95391 3,445.91 100.00 3,545.91 270 390-97865-00 256-270-12 TAXERA, BONNIE 134 W AVENTINO AVE 134 W AVENTINO AVE MOUNTAIN HOUSE, CA 95391 3,992.98 100.00 4,092.98 271 390-98365-02 254-260-11 HEGOS HEBTOM 159 W CONEJO AVE 159 W CONEJO AVE MOUNTAIN HOUSE, CA 95391 3,413.62 100.00 3,513.62 272 390-98415-00 256-270-13 IRBY, MONIQUE 130 W AVENTINO AVE 130 W AVENTINO AVE MOUNTAIN HOUSE, CA 95391 900.00 100.00 1,000.00 273 390-98730-03 256-270-17 PHANITHA KOGANTI 719 N DEL PRADO ST 5553 CRIMSON CIRCLE FREMONT, CA 94538 2,261.57 100.00 2,361.57 274 390-99600-03 256-360-20 GADDAM VENKATESHAR 538 W BONAVENTURE WAY 4350 CONEJO DR DANVILLE, CA 94506 3,053.37 100.00 3,153.37 275 390-99845-02 256-490-19 HALTON SUEN 646 N MONTEBELLO ST 320 8TH STREET - SUITE 2D OAKLAND, CA 94607 1,715.24 100.00 1,815.24 276 390-99964-00 254-120-05 DEVI, SANGEETA 832 SAMANTHA ST 832 SAMANTHA ST MOUNTAIN HOUSE, CA 95391 976.56 100.00 1,076.56 277 390-63883-04 256-440-19 ZHAO JING R TR 728 N PLUMAS DR 1377 BOBOLINK CIR SUNNYVALE, CA 94087 2,458.09 100.00 2,558.09 TOTAL: $ 548,559.41 $ 27,700.00 $ 576,259.41
Item 8.1
Mountain House                                               Page 204 of 741 RESOLUTION NO. ____

A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF MOUNTAIN HOUSE APPROVING REPORT

OF DELINQUENCIES AS REVISED, CORRECTED OR MODIFIED
WHEREAS, the City of Mountain House (“City”) provides water, sewer, and storm drainage utility services and facilities to properties within the City; and WHEREAS, Section 3-1-302 of the Mountain House Municipal Code establishes a charge for providing, operating, and maintaining storm drainage facilities, wastewater treatment facilities and water treatment facilities and the provision, operation, and maintenance of related systems (the “Utility Charges”); and
WHEREAS, the Utility Charges are charges for services and facilities within the meaning of Health and Safety Code sections 5470 through 5474; and
WHEREAS, Health and Safety Code section 5473 authorizes an entity that has adopted an ordinance or resolution establishing such charges to elect, by resolution approved by a two-thirds vote of the members of its legislative body, to have such charges collected on the tax roll in the same manner, by the same persons, and at the same time as, together with and not separately from, its general taxes, and Health and Safety Code section 5473a authorizes such entity to make that election with respect only to delinquent charges; and
WHEREAS, on June 9, 2026, the City Council adopted Resolution 2026-49, approved by a twothirds vote, electing to have the delinquent charges collected on the tax roll; and WHEREAS, Health and Safety Code sections 5473 and 5473a require that, upon election to collect delinquent Utility Charges on the tax roll, the City shall cause a written report to be prepared each year and filed with the City Clerk, which report shall contain a description of each parcel of real property as to which the charges are delinquent and the amount of the delinquent charge for each such parcel for the year, computed in conformity with the charges prescribed by the applicable ordinance or resolution.

WHEREAS, the City Manager has submitted the attached Report of Delinquencies (Exhibit A) which contains the names and addresses of the record title on the property of the persons liable for charges and penalties due for unpaid utility bills; and WHEREAS, the City Council conducted a public hearing, heard objections from delinquent account holders, modified the report as deemed appropriate, and then adopted the Report of Delinquencies.

NOW, THEREFORE, THE CITY COUNCIL OF THE CITY OF MOUNTAIN HOUSE DOES HEREBY RESOLVE that the City Council confirms the attached Report of Delinquencies (Attachment A) (the “Report”).

BE IT FURTHER RESOLVED that the City Clerk is hereby authorized and directed to file the Report of Delinquencies with the San Joaquin County Auditor/Controller no later than August 10, 2026.

Item 8.1
Mountain House                                               Page 205 of 741 BE IT FURTHER RESOLVED that the City Manager or his/her designee is authorized, with respect to any delinquency paid in full by August 3, 2026, to either remove the delinquency from the Report or request the Auditor/Controller to remove it from the property tax roll. The City Manager is authorized to provide, execute and deliver any verbal or written approvals that may be necessary to implement the foregoing.

PASSED, APPROVED, AND ADOPTED by the City Council of the City of Mountain House at a regular meeting held on the 22nd day of July, 2026, by the following vote:

Item 8.1
Mountain House                                               Page 206 of 741 TITLE: Public Hearing and Adoption of the 2025 Urban Water Management Plan and Water Shortage Contingency Plan
MEETING DATE: July 22, 2026
PREPARED BY: Karen Morgan, Utility Manager
Jodi Almassy, Deputy City Manager

RECOMMENDATION
Staff recommends that the City Council:

1. Conduct a public hearing to receive comments on the public draft 2025 Urban Water Management Plan and 2025 Water Shortage Contingency Plan.

2. Adopt a resolution approving and adopting the 2025 Urban Water Management Plan.

3. Adopt a resolution approving and adopting the 2025 Water Shortage Contingency Plan.

4. Authorize the City Manager, or designee, to submit the adopted 2025 Urban Water Management Plan and Water Shortage Contingency Plan to the California Department of Water Resources and complete all required filings.

BACKGROUND
The California Urban Water Management Planning Act (California Water Code Sections 10610 through 10657) requires every urban water supplier serving more than 3,000 service connections or delivering more than 3,000 acre-feet of water annually to prepare and adopt an Urban Water Management Plan (UWMP) every five years. The Act requires urban water suppliers to evaluate existing and future water demands, available water supplies, drought reliability, conservation programs, and long-term water resource planning. The 2025 UWMP also incorporates the City's Water Shortage Contingency Plan (WSCP), which satisfies the requirements of California Water Code Section 10632.

The UWMP and WSCP are required planning documents and do not, by themselves, authorize construction projects, establish water rates, or implement mandatory water conservation measures.

Rather, they provide the long-term planning framework required by State law.

The City of Mountain House currently serves 7,837 municipal water service connections and supplied approximately 5,207 acre-feet of potable water during 2025, qualifying the City as an Urban Water Supplier under the Urban Water Management Planning Act.

Item 8.2
Mountain House                                               Page 207 of 741 The 2025 UWMP updates the City's previously adopted 2020 Urban Water Management Plan and was prepared in accordance with the California Department of Water Resources' 2025 Urban Water Management Plan Guidebook. The plan evaluates the City's water supply reliability through a 20-year planning horizon and includes projections of future water demands, existing and planned water supplies, drought reliability analyses, water conservation measures, recycled water opportunities, demand management measures, and long-term infrastructure planning.

DISCUSSION
Urban Water Management Plan (UWMP)
The 2025 Urban Water Management Plan (UWMP) concludes that the City possesses sufficient water supplies to reliably meet projected customer demands under normal and single dry-year conditions. The Plan also evaluates a more severe five consecutive dry-year scenario, during which temporary supply shortfalls may occur over the 20-year planning horizon. The City's existing allocation of 9,813 acre-feet per year from the Byron Bethany Irrigation District is adequate to meet current demands of approximately 5,207 acre-feet, while projected demand at buildout is estimated to reach approximately 7,063 acre-feet by 2045, leaving available supply capacity under current water supply entitlements.

Although the City's current water supply is considered reliable, the UWMP recognizes several long-term challenges that could affect future water supply reliability, including:
 Continued dependence on Sacramento-San Joaquin Delta supplies;  Regulatory restrictions affecting Delta exports;
 Climate change and hydrologic variability;
 Potential Delta levee failures and associated saltwater intrusion; and  Changing environmental regulations affecting water supply operations.

The recent regional taste and odor event associated with algae blooms highlighted the importance of maintaining a resilient water system. While the event affected aesthetic water quality characteristics rather than the availability or safety of the City's drinking water supply, it reinforces the importance of continued long-term planning and investment in water system reliability and resiliency.

To improve long-term resiliency, the UWMP identifies continued evaluation of additional water management strategies and future water supply projects, including expanded use of available riparian water rights, recycled water opportunities, groundwater storage, and other regional water supply alternatives. These planning efforts support the City's goal of diversifying its water portfolio while maintaining a reliable water supply for future growth.

Water Shortage Contingency Plan (WSCP)
Item 8.2
Mountain House                                               Page 208 of 741 The Water Shortage Contingency Plan (WSCP) establishes the City's operational framework for responding to water shortages and other events that could disrupt water service. The Plan provides guidance for monitoring water supplies, implementing conservation measures, communicating with customers, and responding to emergency conditions.

The WSCP has been prepared as a stand-alone planning document that may be amended independently of the UWMP as future conditions warrant. The WSCP establishes a comprehensive framework for responding to water shortages and emergency events that include:
 Annual Water Supply and Demand Assessments;
 Six standardized water shortage levels;
 Supply augmentation strategies;
 Demand reduction measures;
 Communication protocols;
 Compliance and enforcement procedures;
 Emergency response planning;
 Seismic risk assessment and mitigation; and
 Annual reporting to the California Department of Water Resources.

The WSCP is intended to provide the City with a structured decision-making framework for responding to both foreseeable droughts and unforeseen emergencies, including infrastructure failures, seismic events, power outages, and other disruptions to water supplies.

Overall, the 2025 UWMP concludes that the City has sufficient water supplies to meet projected customer demands under normal operating conditions throughout the planning horizon. While planning for drought, regulatory changes, and other uncertainties remains essential, the City's existing water supply portfolio and ongoing long-term planning efforts position Mountain House to continue serving existing and future customers reliably.

Council Action
Staff recommends adoption of separate resolutions approving the 2025 Urban Water Management Plan and the 2025 Water Shortage Contingency Plan.

Following adoption, staff will submit both plans to the California Department of Water Resources, the California State Library, and other agencies as required by State law.

Adoption of the plans will maintain the City's compliance with California water planning requirements and support long-term water supply reliability.

FISCAL IMPACT
Item 8.2
Mountain House                                               Page 209 of 741 Preparation of the 2025 Urban Water Management Plan and Water Shortage Contingency Plan was funded through the Water Enterprise Fund as part of the City's adopted operating budget.

Adoption of these planning documents does not authorize construction of capital improvements or commit the City to future expenditures. Projects identified in the UWMP will be evaluated individually through future Capital Improvement Program planning, environmental review, and City Council approval.

Implementation of mandatory conservation measures during declared water shortage conditions may reduce water sales and utility revenues. The financial impacts of drought response actions will continue to be evaluated as part of future water rate studies and financial planning efforts.

STRATEGIC PLAN
Adoption of the proposed resolutions supports the City's Strategic Plan, adopted April 9, 2025, by:
• Promoting environmental stewardship.
• Maintaining regulatory compliance.
• Supporting sustainable development practices.
• Responsibly managing community infrastructure and resources.

CEQA
The proposed action is exempt from the California Environmental Quality Act (CEQA) because it consists of planning and administrative activities that do not authorize or commit the City to any specific physical project. Future projects identified in the plans will undergo separate environmental review, as required.

ACTION FOLLOWING CITY COUNCIL APPROVAL
Following adoption, staff will:
• Submit the adopted 2025 Urban Water Management Plan and Water Shortage Contingency Plan to the California Department of Water Resources, the California State Library, and other agencies as required by the California Water Code.
• Make the adopted plans available for public inspection on the City's website and at Town Hall. • Continue implementing the City's long-term water conservation and water supply reliability planning efforts consistent with the adopted Urban Water Management Plan.

ATTACHMENTS
Item 8.2
Mountain House                                               Page 210 of 741 Attachment A – Proposed Resolution Adopting the 2025 Urban Water Management Plan Attachment B – Proposed Resolution Adopting the 2025 Water Shortage Contingency Plan Attachment C – 2025 Urban Water Management Plan
Attachment D – 2025 Water Shortage Contingency Plan
Attachment E – Notice of Public Hearing (June 26, 2026) Attachment F – Notice of Public Hearing (July 3, 2026)

Item 8.2
Mountain House                                               Page 211 of 741

ATTACHMENT A
RESOLUTION NO. 2026-
A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF MOUNTAIN HOUSE ADOPTING THE 2025

URBAN WATER MANAGEMENT PLAN
WHEREAS, the California Urban Water Management Planning Act (California Water Code Sections 10610 through 10657) requires every urban water supplier providing water for municipal purposes to more than 3,000 service connections or supplying more than 3,000 acre-feet of water annually to prepare and adopt an Urban Water Management Plan every five years; and WHEREAS, the City of Mountain House is an urban water supplier subject to the requirements of the Urban Water Management Planning Act; and
WHEREAS, the City has prepared the 2025 Urban Water Management Plan in accordance with the requirements of the California Water Code and the California Department of Water Resources 2025 Urban Water Management Plan Guidebook; and
WHEREAS, the City provided public notice, made the draft 2025 Urban Water Management Plan available for public review, and conducted a duly noticed public hearing in accordance with California Water Code Section 10642; and
WHEREAS, the 2025 Urban Water Management Plan evaluates current and projected water demands, existing and future water supplies, water service reliability, drought risk, demand management measures, conservation programs, and long-term water resource planning; and WHEREAS, the City Council has reviewed the 2025 Urban Water Management Plan and finds that adoption of the Plan serves the best interests of the City and its water customers and maintains compliance with the California Urban Water Management Planning Act.

NOW, THEREFORE, BE IT RESOLVED BY THE CITY COUNCIL OF THE CITY OF MOUNTAIN HOUSE AS FOLLOWS:

1. The City Council hereby adopts the City of Mountain House 2025 Urban Water Management Plan.

2. The City Manager, or designee, is authorized to make non-substantive revisions to the Plan as necessary to address formatting, clerical, or regulatory comments prior to final submission.

3. The City Manager, or designee, is directed to submit the adopted 2025 Urban Water Management Plan to the California Department of Water Resources, the California State Library, and any other agencies as required by the California Water Code.

Item 8.2
Mountain House                                               Page 212 of 741

ATTACHMENT B
RESOLUTION NO. 2026-
A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF MOUNTAIN HOUSE ADOPTING THE 2025

WATER SHORTAGE CONTINGENCY PLAN
WHEREAS, California Water Code Section 10632 requires every Urban Water Management Plan to include a Water Shortage Contingency Plan that establishes procedures for responding to water shortages and water supply emergencies; and
WHEREAS, the City of Mountain House is required to prepare and adopt a Water Shortage Contingency Plan as part of its Urban Water Management Plan; and WHEREAS, the City has prepared the 2025 Water Shortage Contingency Plan in accordance with the requirements of California Water Code Section 10632 and applicable guidance issued by the California Department of Water Resources; and
WHEREAS, the City provided public notice, made the draft 2025 Water Shortage Contingency Plan available for public review, and conducted a duly noticed public hearing prior to adoption; and WHEREAS, the Water Shortage Contingency Plan establishes six standard water shortage levels, annual water supply and demand assessment procedures, shortage response actions, communication protocols, compliance and enforcement procedures, emergency response actions, seismic risk assessment and mitigation measures, and monitoring and reporting requirements; and WHEREAS, the City Council has reviewed the 2025 Water Shortage Contingency Plan and finds that adoption of the Plan serves the best interests of the City and its water customers by promoting reliable water service, protecting public health, supporting emergency preparedness, and maintaining compliance with California Water Code Section 10632.

NOW, THEREFORE, BE IT RESOLVED BY THE CITY COUNCIL OF THE CITY OF MOUNTAIN HOUSE, AS FOLLOWS:

1. The City Council hereby adopts the City of Mountain House 2025 Water Shortage Contingency Plan.

2. The City Manager, or designee, is authorized to make non-substantive revisions to the Plan as necessary to address formatting, clerical, or regulatory comments prior to final submission.

3. The City Manager, or designee, is authorized to implement administrative procedures and make minor administrative modifications necessary to administer the Plan consistent with its provisions.

4. The City Manager, or designee, is directed to submit the adopted 2025 Water Shortage Contingency Plan, as part of the Urban Water Management Plan, to the California Department of Water Resources, the California State Library, and any other agencies as required by the California Water Code.

Item 8.2
Mountain House                                               Page 213 of 741 City of Mountain House
2025 Urban Water Management Plan
DRAFT
MAY 2026
Prepared for:

CITY OF MOUNTAIN HOUSE
251 East Main Street
Mountain House, CA 95391
Prepared by:

BLACK WATER CONSULTING ENGINEERS, INC.
602 Lyell Drive
Modesto, CA 95356
(209) 322-1820

ATTACHMENT C
Item 8.2
Mountain House                                               Page 214 of 741 City of Mountain House
2025 Urban Water Management Plan
May 2026
i

CITY OF MOUNTAIN HOUSE
2025 URBAN WATER MANAGEMENT PLAN

CONTACT SHEET
Date plan adopted: June 24, 2026
Karen Morgan, Utility Manager
City of Mountain House
Phone: (209) 831-5648
Email: [email protected]
Matthew Gutierrez, Program Manager
City of Mountain House
Phone: (209) 831-2300
Email: [email protected]
Aja Verburg, P.E., Vice President
Black Water Consulting Engineers, Inc.

Phone: (209) 753-0078
Email: [email protected]
Bao Cha, E.I.T., Assistant Project Manager
Black Water Consulting Engineers, Inc.

Phone: (209) 694-4766
Email: [email protected]
Andrew Ruiz, E.I.T., Assistant Engineer
Black Water Consulting Engineers, Inc.

Phone: (209) 488-4051
Email: [email protected]

ATTACHMENT C
Item 8.2
Mountain House                                               Page 215 of 741 City of Mountain House
2025 Urban Water Management Plan
May 2026
ii

TABLE OF CONTENTS
1 UWMP Introduction and Lay Description .......................................................................................... 1-1

1.1 Background and Purpose ........................................................................................................... 1-1

1.2 Previous Urban Water Management Plan ................................................................................. 1-1

1.3 Urban Water Management Planning and the California Water Code ....................................... 1-1

1.3.1 Urban Water Management Planning Act of 1983 ............................................................. 1-1

1.3.2 Applicable Changes to the Water Code Since the 2020 UWMP ........................................ 1-2

1.4 UWMPs in Relation to Other Planning Efforts ........................................................................... 1-3

1.5 UWMP Organization .................................................................................................................. 1-3

1.6 Lay Description ........................................................................................................................... 1-4 2 UWMP Preparation ............................................................................................................................ 2-1

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

2.1.1 Public Water Systems......................................................................................................... 2-1

2.2 Individual Planning and Compliance .......................................................................................... 2-2

2.3 Fiscal or Calendar Year and Units of Measure ........................................................................... 2-2

2.4 Coordination and Outreach ....................................................................................................... 2-3

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

2.4.2 Coordination with Other Agencies and the Community .................................................... 2-4

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

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

3.2 Service Area Boundary Maps ..................................................................................................... 3-1

3.3 Service Area Climate .................................................................................................................. 3-4

3.4 Service Area Population and Demographics .............................................................................. 3-5

3.4.1 Service Area Population ..................................................................................................... 3-5

3.4.2 Other Social, Economic, and Demographic Factors ........................................................... 3-5

3.5 Land Uses within Service Area ................................................................................................... 3-6 4 Water Use Characterization............................................................................................................... 4-1

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

4.2 Past, Current, and Projected Water Use by Sector .................................................................... 4-1

4.2.1 Water Use Sectors Listed in Water Code ........................................................................... 4-2

4.2.2 Water Use Sectors in Addition to Those Listed in Water Code ......................................... 4-3

4.2.3 Past Water Use ................................................................................................................... 4-3

4.2.4 Current Water Use ............................................................................................................. 4-4

4.2.5 Projected Water Use .......................................................................................................... 4-5

4.2.6 Water Use for Lower Income Households ......................................................................... 4-8

4.2.7 Climate Change Considerations ......................................................................................... 4-9

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

4.4 Progress Toward Meeting the Water Loss Performance Standard ......................................... 4-11 5 SB X7-7 Baselines, 2020 Targets, and 2025 Reporting ...................................................................... 5-1

5.1 Baseline and Target Calculations for 2025 UWMPs ................................................................... 5-1

5.2 Funding Eligibility ....................................................................................................................... 5-2 6 Normal-Year Water Supply Characterization .................................................................................... 6-1

6.1 UWMP Water Supply Characterization ...................................................................................... 6-1

6.1.1 Purchased or Imported Water ........................................................................................... 6-2

ATTACHMENT C
Item 8.2
Mountain House                                               Page 216 of 741 City of Mountain House
2025 Urban Water Management Plan
May 2026
iii

6.1.2 Groundwater ...................................................................................................................... 6-2

6.1.3 Surface Water .................................................................................................................... 6-4

6.1.4 Stormwater ........................................................................................................................ 6-4

6.1.5 Wastewater and Recycled Water ...................................................................................... 6-4

6.1.6 Desalinated Water Opportunities .................................................................................... 6-12

6.1.7 Water Exchanges and Transfers ....................................................................................... 6-13

6.1.8 Supply from Storage ......................................................................................................... 6-13

6.1.9 Future Water Projects ...................................................................................................... 6-13

6.1.10 Summary of Existing and Planned Sources of Water ....................................................... 6-15

6.1.11 Special Conditions ............................................................................................................ 6-18

6.2 Energy Use ............................................................................................................................... 6-18 7 Water Service Reliability and Drought Risk Assessment ................................................................... 7-1

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

7.1.1 Legal ................................................................................................................................... 7-1

7.1.2 Environmental .................................................................................................................... 7-2

7.1.3 Water Quality ..................................................................................................................... 7-2

7.1.4 Climatic Factors .................................................................................................................. 7-2

7.2 Water Service Reliability Assessment (WSRA) ........................................................................... 7-3

7.2.1 WSRA Year-Type Characterization ..................................................................................... 7-3

7.2.2 Service Reliability – Supply and Demand Comparison ....................................................... 7-5

7.2.3 Description of Management Tools and Options ................................................................ 7-7

7.3 Drought Risk Assessment ........................................................................................................... 7-8

7.3.1 DRA Data, Methods, and Basis for Water Shortage Conditions ........................................ 7-9

7.3.2 DRA Water Source Reliability ............................................................................................. 7-9

7.3.3 Total Water Supply and Use Comparison .......................................................................... 7-9 8 Water Shortage Contingency Plan ..................................................................................................... 8-1 9 Demand Management Measures ...................................................................................................... 9-1

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

9.2 Report Implementation ............................................................................................................. 9-1

9.2.1 Implementation over the Past Five Years .......................................................................... 9-1

9.2.2 Implementation to Achieve Water Use Targets ................................................................ 9-2

9.3 Existing Demand Management Measures for Retail Suppliers.................................................. 9-2

9.3.1 Water-Waste Prevention Ordinances ................................................................................ 9-3

9.3.2 Metering............................................................................................................................. 9-3

9.3.3 Conservation Pricing .......................................................................................................... 9-4

9.3.4 Public Education and Outreach .......................................................................................... 9-4

9.3.5 Programs to Assess and Manage Distribution System Real Loss ....................................... 9-5

9.3.6 Water Conservation Program Coordination and Staffing Support .................................... 9-6

9.3.7 Other Demand Management Measures ............................................................................ 9-6 10 UWMP Adoption, Submittal, and Implementation ......................................................................... 10-1

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

10.2 Notice of Plan Preparation ....................................................................................................... 10-1

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

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

10.4.1 Public Hearing .................................................................................................................. 10-3

10.4.2 Adoption .......................................................................................................................... 10-3

ATTACHMENT C
Item 8.2
Mountain House                                               Page 217 of 741 City of Mountain House
2025 Urban Water Management Plan
May 2026
iv

10.5 Plan Submittal .......................................................................................................................... 10-3

10.5.1 Submitting a UWMP and Water Shortage Contingency Plan to DWR ............................. 10-4

10.5.2 Electronic Data Submittal ................................................................................................ 10-4

10.5.3 Submitting a UWMP, including WSCP, to the California State Library ............................ 10-4

10.5.4 Submitting a UWMP to Cities and Counties .................................................................... 10-4

10.6 Public Availability ..................................................................................................................... 10-4

10.7 Notification to Public Utilities Commission ............................................................................. 10-4

10.8 Plan Implementation ............................................................................................................... 10-4

10.9 Amending an Adopted UWMP or Water Shortage Contingency Plan ..................................... 10-5

10.9.1 Amending a UWMP .......................................................................................................... 10-5

10.9.2 Amending a Water Shortage Contingency Plan ............................................................... 10-5 11 References ....................................................................................................................................... 11-1

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) ........................................................................................ 2-2 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 – UWMP Coordination ............................................................................................................... 2-5 Table 3-1 – City of Mountain House Climate Data .................................................................................... 3-4 Table 3-2 – Population - Current and Projected (DWR Table 3-1 Retail) ................................................... 3-5 Table 3-3 – Demographic Factors .............................................................................................................. 3-6 Table 4-1 – Past Water Use (2020-2024) ................................................................................................... 4-3 Table 4-2 – Total Uses for Potable and Non-Potable Water – Actual (DWR Table 4-1 Retail) .................. 4-4 Table 4-3 – Total Uses of Potable and Non-Potable Water – Projected (DWR Table 4-2 Retail) .............. 4-7 Table 4-4 – Inclusion in Water Use Projections (DWR Table 4-3 Retail) .................................................... 4-8 Table 4-5 – City of Mountain House Low Income Projected Water Demand ............................................ 4-9 Table 4-6 – Water Loss Audit Reporting (DWR Table 4-5 Retail) ............................................................. 4-10 Table 4-7 – Progress Towards 2028 Water Loss Standard (DWR Table 4-6 Retail) ................................. 4-12 Table 5-1 – SB X7-7 2020 Target Progress (DWR Table 5-1 Retail) ............................................................ 5-2 Table 6-1 – Groundwater Volume Pumped (DWR Table 6-1 Retail).......................................................... 6-3 Table 6-2 – Wastewater Collected within Service Area (DWR Table 6-2 Retail) ....................................... 6-7 Table 6-3 – Wastewater Treatment and Discharge within Service Area (DWR Table 6-3 Retail) ............. 6-8 Table 6-4 – Current and Projected Recycled Water Direct Beneficial Uses Within Service Area (DWR Table 6-4 Retail) ................................................................................................................................................. 6-10 Table 6-5 – 2020 UWMP Recycled Water Use Projection Compared to 2025 Actual (DWR Table 6-5 Retail) ................................................................................................................................................................. 6-11 Table 6-6 – Methods to Expand Future Recycled Water Use (DWR Table 6-6 Retail)............................. 6-12 Table 6-7 – Expected Future Water Supply Projects or Program (DWR Table 6-7 Retail) ....................... 6-15 Table 6-8 – Water Supplies – 2025 Actual (DWR Table 6-8 Retail).......................................................... 6-16 Table 6-9 – Water Supplier – Projected (DWR Table 6-9 Retail) ............................................................. 6-17 Table 7-1 – Basis of Water Year Data (DWR Table 7-1 Retail) ................................................................... 7-4 Table 7-2 – Normal Year Supply and Use Comparison (DWR Table 7-2 Retail) ......................................... 7-5 Table 7-3 – Single-Dry Year Supply and Demand Comparison (DWR Table 7-3 Retail) ............................. 7-6

ATTACHMENT C
Item 8.2
Mountain House                                               Page 218 of 741 City of Mountain House
2025 Urban Water Management Plan
May 2026
v
Table 7-4 – Multiple-Dry Years Supply and Demand Comparison (DWR Table 7-4 Retail) ....................... 7-7 Table 7-5 – Five-Year Drought Risk Assessment Tables (DWR Table 7-5 Retail) ..................................... 7-10 Table 10-1 – Retail Notification to Cities and Counties (DWR Table 10-1 Retail) .................................... 10-2

LIST OF FIGURES
Figure 3-1 – City of Mountain House Water System Map ......................................................................... 3-3 Figure 3-2 – Land Use Diagram .................................................................................................................. 3-8

APPENDICES
Appendix A – DWR UWMP Tables
Appendix B – DWR UWMP Checklist
Appendix C – Agency and Public Notices
Appendix D – Water Loss Audits (2020-2023)
Appendix E – Byron Bethany Irrigation District Water Services Agreement Appendix F – Energy Use Tables
Appendix G – 2024 Consumer Confidence Report
Appendix H – Water Shortage Contingency Plan
Appendix I – City of Mountain House Municipal Code
Appendix J – Water and Wastewater Rate Study
Appendix K – UWMP Adoption Resolution

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LIST OF ACRONYMS AND ABBREVIATIONS
AB Assembly Bill
AF Acre-feet
AFY Acre-feet per year
AMI Advanced Metering Infrastructure
ASR Aquifer Storage and Recovery
BBID Byron Bethany Irrigation District
CIMIS California Irrigation Management Information System City City of Mountain House
CWC California Water Code
DMM Demand Management Measures
DOF California Department of Finance
DPR Direct Potable Reuse
DRA Drought Risk Assessment
DWR California Department of Water Resources
ET Evapotranspiration
gpcd, GPCD gallons per capita per day
GPSCD gallons per service connection per day
HCF hundred cubic feet
Legislature State of California Legislature
MG Million gallons
mgd, MGD Million gallons per day
PWS Public Water System
SB Senate Bill
SGMA Sustainable Groundwater Management Act
SSJID South San Joaquin Irrigation District
SWP State Water Project
SWRCB State Water Resources Control Board
UWMP Urban Water Management Plan
UWMPA Urban Water Management Plan Act
UWMP Guidebook 2025 Urban Water Management Plan Guidebook for Urban Water Suppliers Water Master Plan Potable Water System Master Plan Update WSCP Water Shortage Contingency Plan
WSRA Water Service Reliability Assessment
WWCP Wastewater Change Petition
WWTP Wastewater Treatment Plant
2017 Rate Study 2017 Water and Wastewater Rate Study

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1 UWMP Introduction and Lay Description

1.1 Background and Purpose
Legal Requirements:

CWC 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.

The California Water Code (CWC) requires urban water suppliers within the state to prepare and adopt Urban Water Management Plans (UWMPs) for submission to the California Department of Water Resources (DWR). The UWMPs, which must be filed every five years, must satisfy the requirements of the Urban Water Management Planning Act (UWMPA) of 1983 including amendments that have been made to the UWMPA and other applicable regulations. The UWMPA requires urban water suppliers servicing 3,000 or more connections or supplying more than 3,000 acre-feet (AF) of water annually, to prepare a UWMP.

The purpose of the UWMP is to maintain efficient use of urban water supplies, continue to promote conservation programs and policies, ensure that sufficient water supplies are available for future beneficial use, and provide a mechanism for response during water drought conditions. This plan, which was prepared in compliance with the CWC, and as set forth in the 2025 Urban Water Management Plan Guidebook for Urban Water Suppliers (January 2026) established by DWR (UWMP Guidebook), constitutes the City of Mountain House (City) 2025 UWMP. This 2025 UWMP was prepared in compliance with the UWMPA and the Water Conservation Bill of 2009 (Senate Bill [SB] X7-7) by Black Water Consulting Engineers, Inc. and the City.

1.2 Previous Urban Water Management Plan
The City previously updated its 2020 UWMP in May 2022. Following adoption, the 2020 UWMP was submitted to and approved by DWR. This 2025 UWMP serves as an update to the 2020 UWMP and complies with all new UWMP requirements and regulations.

1.3 Urban Water Management Planning and the California Water Code This section summarizes the CWC sections that are applicable to UWMPs.

1.3.1 Urban Water Management Planning Act of 1983
In 1983, State Assembly Bill (AB) 797 modified the CWC Division 6, by creating the UWMPA. Several amendments to the original UWMPA, which were introduced since 1983, have increased the data requirements and planning elements to be included in UWMPs. Initial amendments to the UWMPA required that total projected water use be compared to water supply sources over the next 20 years, in

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5-year increments. Recent DWR guidelines also suggest projecting through a 25-year planning horizon to maintain a 20-year timeframe until the next UWMP update has been completed. This is merely a guideline and not a requirement of the UWMPA. Therefore, the use of a 25-year planning horizon as opposed to a 20-year planning horizon is left up to the discretion of the agency. The City has opted to use a 20-year planning horizon in this 2025 UWMP.

1.3.2 Applicable Changes to the Water Code Since the 2020 UWMP Since the UWMPA was enacted, the CWC has continued to evolve in response to statewide water management challenges such as prolonged drought, groundwater overdraft, regulatory updates, and changing climatic conditions. These factors influence each Supplier’s water reliability determinations as well as the broader statewide reliability framework overseen by DWR, the State Water Resources Control Board (SWRCB), and the State of California Legislature (Legislature).

Summarized below are the major additions and changes to the UWMP requirements since the 2020 UWMP as per the DWR’s UWMP guidance documents:
• Changes in Water Code – There have been minor changes to the Water Code since the 2020 UWMPs were submitted; primarily, several definitions have been added. None of these change UWMP requirements for 2025 UWMPs.
• Suppliers with Multiple Public Water Systems (PWSs) – For consistency among State agencies, DWR and the State Water Board are using the same criteria to determine when a Supplier with multiple PWSs is considered an Urban Water Supplier subject to UWMP requirements. Refer to Chapter 2, Section 2.1.1 of the UWMP Guidebook for details. • DWR Submittal Tables – Submittal tables have been updated to reflect the current reporting year, improve accuracy of reporting, and more clearly identify information required by Water Code and optional information.
• Water Loss Standard Reporting – There has been no change to the Water Code regarding water loss standard reporting since 2020 UWMPs were submitted. However, the existing Water Code requires Suppliers to demonstrate compliance with the 2028 Water Loss Standard. The Water Loss Standards were not available when the 2020 UWMPs were being submitted but are now available for 2025 UWMPs. Therefore, guidance has been added about how Suppliers can now report progress toward compliance with their Water Loss Standard in 2025 UWMPs. Refer to Submittal Table 4-6 and related guidance in Chapter 4 of the UWMP Guidebook. • Direct Potable Reuse – The State Water Board has adopted regulations for the use of direct potable reuse (DPR) since 2020 UWMP reporting. To allow for reporting of DPR, minor changes have been made to supply and demand tables. Refer to guidance in Chapters 4 and 6 of the UWMP Guidebook.
• Lower-Income Housing – While projections for lower-income housing were required in 2020 UWMPs, additional guidance has been provided for optional reporting of the method used to project water use for lower-income housing. This optional guidance incorporates the regional housing needs assessment into projected land uses and water demands. Refer to Chapter 4 and Appendix K of the UWMP Guidebook for more information.
• Reporting Groundwater Recharge and Other Water Storage – In previous years, the guidance for reporting water placed into storage did not differentiate between long-term storage (i.e., water placed into storage one year but extracted in a future year) and short-term storage (i.e., water that is placed into storage and extracted the same year). When a Supplier reports water placed

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into storage and then reports it was retrieved in the same year (short-term storage) it can cause a double counting error. Additional guidance recommending that Suppliers do not report water into and out of short-term storage is provided in Chapter 4 and Chapter 6 of the UWMP Guidebook.

1.4 UWMPs in Relation to Other Planning Efforts
The City is committed to providing a reliable and high-quality water supply to its customers. To ensure that the City will be able to continue to reliably serve the residents of Mountain House in the future, the City has conducted/participated in several important planning efforts that relate to water supply planning and are related to the UWMP. Some of the most recent water planning efforts are summarized below:
• Mountain House Specific Plan 2024 Update [1]: In September 2024, the City adopted an update to its Specific Plan, which collectively consists of three Specific Plans (Specific Plan I, Specific Plan II, and Specific Plan III) that govern all City actions related to community’s physical development throughout Buildout. Together, these Specific Plans establish the long-term land use framework, development standards, infrastructure requirements, design guidelines, and implementation measures for distinct planning areas within Mountain House. The 2024 Update ensures that the three Specific Plans remain aligned with the City’s long-term physical and economic development objectives and community enhancement goals and provides a coordinated planning framework to guide future development, public facilities, and infrastructure investments. • Potable Water System Master Plan Update (Water Master Plan) [2]: The City published its Water Master Plan in 2020. The Master Plan sets the foundation for the City to expand its water system to meet the needs of its growing population through buildout, as defined in the City’s Specific Plan updated in 2024.

1.5 UWMP Organization
This 2025 UWMP contains the appropriate sections and tables required per the UWMPA and has been prepared based on guidance provided by the UWMP Guidebook. The required tables are included in the relevant sections and in Appendix A.

DWR’s UWMP Checklist, as provided in the UWMP Guidebook, has been completed to demonstrate the UWMP’s compliance with applicable requirements. A copy of the completed checklist is included in Appendix B. This plan is organized according to the recommended format provided in the UWMP Guidebook. The UWMP contains ten chapters as outlined below, followed by appendices that provide supporting documentation for the information presented in the plan. • Chapter 1 – UWMP Introduction and Lay Description: This chapter provides background information for the 2025 UWMP and provides a description of the purpose of the plan. • Chapter 2 – UWMP Preparation: This chapter includes information on the development of the 2025 UWMP and efforts in coordination and outreach.
• Chapter 3 – Service Area Description: This chapter describes the service area, population, and climate; presents an overview of the City’s water distribution system; and describes the City's organizational structure and history.
• Chapter 4 – Water Use Characterization: This chapter describes and quantifies the current and projected water uses within the City’s service area.

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• Chapter 5 – SB X7-7 Baseline, 2020 Targets, and 2025 Reporting: This chapter describes the methods for calculating baseline and target water use consumption in the City. It also includes a calculation of the City’s 2025 water use and determination of compliance with the 2025 target water use.
• Chapter 6 – Normal-Year Water Supply Characterization: This chapter describes the current and projected sources of water available to the City. A description of potential recycled water use and supply availability is also included in this chapter.
• Chapter 7 – Water Service Reliability and Drought Risk Assessment: This chapter describes the reliability of the City’s current supply and evaluates the reliability 20 years out, including normal, single-dry years, and five consecutive dry years.
• Chapter 8 – Water Shortage Contingency Plan: This chapter references the City’s Water Shortage Contingency Plan (WSCP) which is provided in Appendix H. • Chapter 9 – Demand Management Measures: This chapter describes the City's efforts to promote conservation, reduce water demand, and describes the City's demand management measures. • Chapter 10 – UWMP Adoption, Submittal, and Implementation: This chapter describes the steps taken to adopt and submit the 2025 UWMP and make it publicly available. This chapter will also describe the City's plan to implement the UWMP.

1.6 Lay Description
Legal Requirements:

CWC 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.

The City provides potable water service to a growing residential and commercial community located in San Joaquin County. Mountain House is a planned community that continues to experience steady growth. As per the California Department of Finance’s (DOF) Population Estimate Table [3], the City’s current population is approximately 28,800 and is projected to increase to about 39,000 at buildout, which is expected around 2040. As development continues, water demand will increase accordingly, driven primarily by residential growth, along with supporting commercial, industrial, and institutional land uses.

The City’s water system includes a surface water treatment plant, storage tanks, a booster pump station, and an extensive distribution network that delivers treated water to customers throughout the service area. Currently, the City relies entirely on surface water purchased from Byron Bethany Irrigation District (BBID). This water originates primarily from the State Water Project, which conveys water from the Sacramento–San Joaquin Delta to the region. The City treats this water at its treatment plant before distributing it to customers. The existing supply is considered reliable under normal conditions and is sufficient to meet current demands.

On a reliable basis, the City is allocated up to 9,813 acre-feet per year (AFY) from BBID which is a sufficient water supply to meet approximately 5,207 AF of demand in 2025. Looking ahead, total water demand is projected to increase to approximately 7,063 AF by 2045 as the community reaches buildout.

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To meet future water needs, the City will continue to rely on its existing surface water supply from BBID while evaluating additional water supply and management strategies. Potential future supplies may include the use of Old River water in certain areas which would add approximately 2,570 AFY to the existing water supply. Along with other long-term supply options currently under evaluation, these efforts are intended to ensure that the City can meet demand under both normal and drought conditions.

The City has evaluated its water supply reliability over a 20-year planning horizon, including normal years, single-dry years, and extended drought conditions. While the current supply is generally adequate, the City may face challenges that could affect future reliability. These include regulatory restrictions on Delta water diversions, potential impacts from climate change, and risks associated with Delta levee failure and saltwater intrusion.

To address these challenges, the City is actively planning for long-term water reliability. This includes evaluating alternative water supplies, improving system flexibility, and coordinating with regional partners. In addition, the City has developed a WSCP that outlines specific actions to be implemented during water shortages, including demand reduction measures and public outreach.

Overall, the City has a reliable water supply to meet current demands and has developed a comprehensive strategy to meet future needs. Through continued planning, investment, and conservation efforts, the City aims to ensure a sustainable and resilient water supply for its community.

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2 UWMP Preparation
This chapter provides information on the processes used for developing the 2025 UWMP, including coordination and outreach efforts.

2.1 Basis for Preparing a Plan
Legal Requirements:

CWC 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.

Water Code Section 10608.12
(t) “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 acrefeet of potable water annually at retail for municipal purposes. (w) “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.

CWC Section 10620:
(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.

CWC 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.

2.1.1 Public Water Systems
The CWC defines an urban water supplier as “a water supplier, either publicly or privately owned, that directly provides potable municipal water to more than 3,000 end users or supplies more than 3,000 AF of potable water annually at retail for municipal purposes.” Table 2-1 (DWR Table 2-1 Retail) documents the number of municipal connections and the volume of water supplied in 2025. The City is considered an urban retail water supplier.

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Table 2-1 – Public Water Systems (DWR Table 2-1 Retail) Submittal Table 2-1 Retail: Public Water Systems
Public Water System
Number
Public Water System
Name
Number of Municipal
Connections 2025
Volume of Water
Supplied 2025
Add additional rows as needed
CA3910027 City of Mountain House 7,837 5,207
Total 7,837 5,207
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 Table 2-3.

NOTES: Unit of measure for volumes are in AF.

2.2 Individual Planning and Compliance
Water agencies are given the option to develop UWMPs individually or collectively as a regional group.

While efforts to prepare the UWMP were coordinated with appropriate agencies, this 2025 UWMP was developed for the City service area only, and the City is not participating in a Regional UWMP as specified in Table 2-2 (DWR Table 2-2).

Table 2-2 – Plan Identification (DWR Table 2-2)
Submittal Table 2-2: Plan Identification
Select
One or
Both
Type of Plan Name of Regional Alliance or
RUWMP (Drop Down List)
Individual UWMP

If Water Supplier is also a member of a SB X7-7
Regional Alliance, select name from the dropdown.

Regional Urban Water Management Plan (RUWMP)

If Supplier selected RUWMP, select name from
the drop-down.

NOTES: No additional notes.

2.3 Fiscal or Calendar Year and Units of Measure
Legal Requirements:

CWC Section 10608.20:
(a)(1) Urban retail water suppliers…may determine the targets on a fiscal year or calendar year basis.

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The City’s 2025 UWMP has been prepared on a calendar year basis and includes planning data for the entire year of 2025. The City’s reporting of water volumes in this 2025 UWMP is reported in AFY. Table 2- 3 (DWR Table 2-3) summarizes the City’s reporting methods for this 2025 UWMP.

Table 2-3 – Supplier Identification (DWR Table 2-3)
Submittal Table 2-3: Supplier Identification
Type of Supplier (select one or both)
Supplier is a wholesale supplier
Supplier is a retail supplier
Fiscal or Calendar Year (select one)
UWMP Tables are in calendar years
UWMP Tables are in fiscal years
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).

Unit AF
DWR NOTES:

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

NOTES: No additional notes.

2.4 Coordination and Outreach
Legal Requirements:

CWC Section 10631:
(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).

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The UWMPA requires that the UWMP identify the water agency’s coordination with appropriate nearby agencies. While preparing the 2025 UWMP, the City coordinated its efforts with relevant agencies to ensure that the data and issues are presented accurately.

2.4.1 Wholesale and Retail Coordination
The City is a retail agency that receives its supply of water from BBID, a wholesale agency. As of the submittal of this UWMP, the City has notified BBID of their projected water use in the service area for the next 20 years as shown in Table 2-4 (DWR Table 2-4 Retail).

Table 2-4 – Water Supplier Information Exchange (DWR Table 2-4 Retail) 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
Add additional rows as needed
Byron Bethany Irrigation District
NOTES: No additional notes.

2.4.2 Coordination with Other Agencies and the Community Legal Requirements:

CWC Section 10620:
(d)(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.

CWC 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 the plan...

The City coordinated the preparation of its UWMP and WSCP with numerous local and regional agencies, including public agencies that rely on related or interconnected water supplies. Table 2-5 provides a list of agencies consulted during the development of this Plan.

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Table 2-5 – UWMP Coordination
Agencies
Byron Bethany Irrigation District
City of Tracy
City of Manteca
South San Joaquin Irrigation District
San Joaquin County
Association of California Water Agencies
The Resmark Companies
Kamilos Companies
Trimark Communities, LLC
California Department of Water Resources
The City also maintains an ongoing commitment to public involvement in water resource planning. Public participation is encouraged through a variety of methods, including direct mailings, public meetings, and web-based communications. The City website provides updates on ongoing water system projects, public notices, and proposed rate adjustments related to water system improvements.

A public hearing will be held for review and comment on the draft UWMP before City Council approval.

Additionally, copies of the draft and final UWMP will be posted on the City’s website homepage.

2.4.3 Notice to Cities and Counties
Legal Requirements:

CWC Section 10621(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.

In accordance with CWC Section 10621, a notice of preparation must be sent to the City or County at least 60 days prior to the public hearing date. Noticing for the public hearing was conducted pursuant to Section 6066 of the Government Code prior to commencement of the public comment period. This notification is reported in Table 10-1 (DWR Table 10-1 Retail). Copies of the public hearing notices and notices to city and county entities served by the City, as well as other agencies, are included in Appendix C. The notices included the UWMP update schedule and contact information.

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3 Service Area Description
The UWMPA requires that the UWMP include a description of the water purveyor’s service area and various aspects of the area served including climate, population, and other demographic factors.

3.1 General Description
Legal Requirements:

CWC Section 10631:
(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 fiveyear 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.

The City is a master-planned community located in southwestern San Joaquin County, approximately 3.5 miles west of the City of Tracy, directly east of the Alameda County border line, north of Interstate 205, and south of the Old River. The City is a full-service community providing a range of municipal services, including public safety, parks and recreation, public works, water distribution, wastewater collection, stormwater management, and general administrative services. With the City planned to be a selfsufficient community, the community upon buildout will consist of 12 neighborhoods each with a park, school, and small community, commercial spaces, industrial parks, and office buildings.

The City’s water system serves a growing population through a surface-water-based supply and a modern distribution system. The system is supplied with surface water purchased from BBID, which, under their established water services agreement, can provide the City with approximately 9,813 AFY of State Water Project water to the community. The water system includes one surface water treatment plant, four treated water storage tanks, one booster pump station, and approximately 74 miles of distribution pipelines ranging from 6 to 36 inches in diameter. Most existing pipelines are polyvinyl chloride, with the remainder being ductile iron or cement-lined steel. Water is delivered through two pressure zones supported by the system’s storage and pumping facilities. Zone 1 serves elevations from sea level to approximately 100 ft msl, while Zone 2 serves elevations from approximately 85 to 189 ft msl. Additional system details, including planned capital improvements and long-term supply enhancements, are provided in the City’s Water Master Plan, adopted in December 2020 [2].

3.2 Service Area Boundary Maps
The City’s water service area encompasses approximately 4,800 acres, or 7.5 square miles. While the City's existing service area is generally contiguous with the City limit, certain newly developing areas may be incorporated into the service area as buildout progresses in accordance with land use plans and infrastructure phasing.

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The City supplies water to approximately 7,837 residential, commercial, industrial, and institutional/government customers. Figure 3-1 presents a location map of the City’s service area and depicts the existing water distribution system.

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3.3 Service Area Climate
Legal Requirements:

CWC Section 10631(a):

Describe the service area of the supplier, including … “climate…” CWC Section 10630:

It is the intention of the Legislature, in enacting this part, to permit levels of water management planning… while accounting for impacts of climate change.

Water use within the City’s service area is dependent on various climate factors such as temperature, precipitation, and evapotranspiration (ET). ET is a term which refers to the amount of water transferred from the Earth’s surface to the atmosphere through evaporation from the soil and surface water bodies and combined with plant transpiration. Climate data, including temperature and precipitation estimates, were obtained from the National Centers for Environmental Information (NCEI) website as well as the California Irrigation Management Information System (CIMIS) where Station #47, located in Brentwood, for the period from January 1988 to September 2025 was used as a reference point for the City. The climatic data for the City is summarized in Table 3-1.

Table 3-1 – City of Mountain House Climate Data
Month
Monthly Average
Temperature (°F)a
Total Monthly
Precipitation
(inches)a
Total Monthly ET
(inches)b
Maximum Minimum
January 57.2 36.4 2.34 1.22
February 62.1 38.9 2.57 2.17
March 68.0 41.6 1.72 3.80
April 73.4 45.0 0.99 5.56
May 80.4 50.3 0.72 7.23
June 88.3 54.9 0.15 8.07
July 93.2 56.6 0.00 8.33
August 92.1 55.6 0.03 7.48
September 88.5 53.5 0.08 5.71
October 78.9 48.1 0.69 3.95
November 66.7 40.7 1.11 1.99
December 56.3 36.4 2.32 1.18
Annual Average 75.4 46.5 1.06 4.72
Total - - 12.72 56.69
(a) Source: NCEI: ncei.noaa.gov, Tracy Carbona, California (048999), Monthly Climate Summary, 1991 - 2020. (b) Source: CIMIS Website: www.cimis.water.ca.gov, Station 47 Brentwood, California, Monthly Average ET Report, Printed on September 2025. [4]
These climate characteristics 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.

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3.4 Service Area Population and Demographics

3.4.1 Service Area Population
Legal Requirements:

CWC Section 10631(a):

Describe the service area of the supplier, including current and projected population …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 City’s current (2025) service area population of 28,795 has been estimated using the California DOF tables from the official State of California website [3]. The City’s population has grown at an average annual rate of 3.3 percent from 2020 through 2025 according to population estimates from the DOF. The DOF estimates that households in the City have an average of 3.8 persons per household with approximately 6,601 total households in 2025.

Growth and development within the City’s service area are subject to City and County growth management policies. Projections of future population within the City’s service area have been made by assuming a uniform growth rate and a buildout population of 39,062 achieved in 2040 based on the City of Mountain House Specific Plan. This equates to an average annual growth rate of 2.05%. The projected service area population from 2020 – 2045 is summarized in Table 3-2 (DWR Table 3-1 Retail).

Table 3-2 – Population - Current and Projected (DWR Table 3-1 Retail) Submittal Table 3-1 Retail: Population - Current and Projected Water Code Section 10631(a)
Population
Served
2025 2030 2035 2040 2045 2050(opt)
28,795 31,876 35,286 39,062 39,062
NOTES: 2025 population served is from DOF, Report E-4, Table 2 for 1/1/2025. Year 2040 population served is from the Mountain House 2020 Water Master Plan.

Projected population values assume a uniform growth rate from 2025 to 2040 of

2.054 percent. Build out for the City is estimated to be in 2040, with minimal population increasing afterwards. Therefore, the 2045 population is the same as the 2040 population. The projections for population served differ from the 2020 UWMP.

3.4.2 Other Social, Economic, and Demographic Factors
Legal Requirements:

CWC Section 10631:
(a) Describe the service area of the supplier, including… other social, economic and demographic factors affecting the supplier’s water management planning.

According to data available through the US Census Bureau American Community Survey [5], the median household income in the City is $171,675. The percent of the population below the poverty level is 2.7%.

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The median age in the City is 34 years old. 92.4% of the population have attained a high school diploma, and 50.9% have a bachelor’s degree or higher. Table 3-3 provides additional information pertaining to Mountain House’s demographic factors.

Table 3-3 – Demographic Factors
Parameter Value
Age and Sex
Persons under 5 years, percent 6.1%
Persons under 18 years, percent 32.2%
Persons 65 years and over, percent 6.9%
Female persons, percent 49.6%
Race and Hispanic Origin
White alone, percent 26.0%
Black or African American alone, percent 5.8%
American Indian and Alaska Native alone, percent 0.2%
Asian alone, percent 55.8%
Native Hawaiian and Other Pacific Islander alone, percent 0.0% Two or More Races, percent 8.6%
Hispanic or Latino, percent 9.0%
White alone, not Hispanic or Latino, percent 21.7%
Source: U.S. Census Bureau for City of Mountain House, California (American Community Survey for 2024)

3.5 Land Uses within Service Area
Legal Requirements:

CWC Section 10631(a):
…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…
The Mountain House community consists of 12 planned neighborhoods, each designed to include a school, a park, public spaces, and residential housing. Complementing these neighborhoods are three Village Centers that provide commercial and service facilities for the community. As a result, land uses within the Mountain House service area are predominantly residential, supported by commercial, institutional, mixed-use, and open-space designations primarily located within the Neighborhood and Village Centers. Undeveloped portions of the service area consist largely of vacant or agricultural lands that are planned for future development as the community continues to grow.

Full buildout of Mountain House is anticipated over the next 20 years and includes completion of the remaining residential neighborhoods, along with the development of key employment and activity centers. According to the Water Master Plan, buildout land uses include approximately 2,486 acres of residential development, 502 acres of commercial land, 382 acres of industrial land, 525 acres of open space, and 423 acres designated for public and school facilities.

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Figure 3-2 shows a map of general land use distribution within the City. The Mountain House Specific Plans [1] provide detailed land use designations and future development patterns.

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4 Water Use Characterization
This chapter describes and quantifies the current and projected water demands within the City’s service area.

4.1 Non-Potable versus Potable Water Use
Potable water refers to water that is safe for human consumption and has undergone the necessary treatment and disinfection processes to comply with applicable drinking water standards. The City relies exclusively on potable water supplied by BBID as its sole source of water, which serves all potable needs within the established service area.

Non-potable water is not currently utilized within the City; however, efforts are underway to enable future use. As discussed in Chapter 6, the City’s wastewater is treated to Title 22 disinfected tertiary recycled water standards, but recycled water cannot yet be delivered to customers due to the absence of necessary distribution infrastructure and required State approvals. To support future non-potable water use, the City intends to evaluate the feasibility of implementing a recycled water program to supplement the potable water supply and provide recycled water for residential, commercial, and landscape irrigation demands within the service area.

Raw water, another type of non-potable supply, consists of untreated water used in its natural condition or with minimal treatment. Although the City does not currently utilize raw water, future plans may include the use of raw water to supply or replenish lakes and other planned features identified in longterm development and infrastructure planning documents.

4.2 Past, Current, and Projected Water Use by Sector
Legal Requirements:

CWC 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.

CWC Section 10631(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… (2) The water use projections shall be in the same five-year increments described in subdivision (a).

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(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.

The following sections describe past, current, and projected water use within the City for each of the 10 water use sectors identified in CWC Section 10631(d).

4.2.1 Water Use Sectors Listed in Water Code
Legal Requirements:

CWC Section 10631(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.

The water use sectors that are served by the City’s water system, include single-family residential, multifamily residential, commercial, institutional/governmental, landscape irrigation, other, and distribution system water losses. These classifications were used to analyze current consumption patterns among various types of customers. These classifications are defined by the Guidebook as follows:
• 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. • Institutional/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.

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• Landscape – Water connections supplying water solely for landscape irrigation. Such landscapes may be associated with single-family residential, multi-family residential, commercial, industrial, or institutional/governmental sites, but are considered a separate water-use sector if the connection is solely for landscape irrigation.
• Other – Any water use that is not adequately described by the water sectors defined above or water uses that are not separately classified.
• Distribution System Losses – Water losses which occur due to distribution system leaks and other unmetered water uses (such as firefighting, main flushing, etc.).

Additional sectors that are not applicable to the City’s water system include: sales to other agencies, groundwater recharge, saline water intrusion barriers or conjunctive use, and agricultural.

4.2.2 Water Use Sectors in Addition to Those Listed in Water Code The water system’s additional land uses per the CWC include fire flows and construction water. As the City continues to expand their service area via the development of additional housing and city utilities, the usage of construction water will be more prevalent in the City’s projected water use.

4.2.3 Past Water Use
Legal Requirements:

CWC Section 10631(d):
(1) For an urban retail water supplier, quantify, to the extent records are available, past… water use… based upon information developed pursuant to subdivision (a), identifying the uses among water use sectors…
The City’s past water use for 2020-2024 is shown in Table 4-1. 2020-2024 water use is based on consumption and production data provided by the City. Water losses are estimated as the difference between total consumption and total production. Variations in water use during this period reflect a combination of climate variability, conservation measures, and changes in customer behavior.

Table 4-1 – Past Water Use (2020-2024)
Water Use Category
Actual Demand, AFY
2020 2021 2022 2023 2024
Single Family 2,743 2,780 2,735 2,582 2,763
Multi-Family 395 417 431 416 457
Commercial 62 21 11 19 26
Institutional/Governmental 351 324 264 241 340
Landscape 718 875 779 723 964
Other 11 11 11 10 11
Losses 356 443 466 437 424
Total Water Demand 4,636 4,871 4,696 4,427 4,985
Note: The “Other” water use category accounts for unbilled unmetered water consumption and is estimated as 0.25% of the total billed consumption, in accordance with the AWWA water loss audit form.

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4.2.4 Current Water Use
Legal Requirements:

CWC Section 10631(d):
(1) For an urban retail water supplier, quantify, to the extent records are available, … current water use… based upon information developed pursuant to subdivision (a), identifying the uses among water use sectors…
Water demand by land use type is presented in Table 4-2 (DWR Table 4-1 Retail). As shown, all water deliveries in 2025 were treated to drinking water standards. The City did not supply water to retail water suppliers in 2025 and does not anticipate providing wholesale service in the future. Total water demand for 2025 was 5,207 acre-feet, which includes system losses. The City uses water loss audits to identify system inefficiencies and prioritized maintenance and capital improvements to reduce real and apparent losses over time.

Table 4-2 – Total Uses for Potable and Non-Potable Water – Actual (DWR Table 4-1 Retail) Submittal Table 4-1 Retail: Total Uses for Potable and Non-Potable Water — Actual Water Code Section 10631(d)(1)
Use Type
Additional Description
(as needed)
2025 Actual Water Use
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
Add additional rows as needed
Single Family Potable 2,873
Multi-Family Potable 507
Commercial
Builder; Commercial;
Utilities; Construction;
Manufacturing; Mining
Potable 78
Institutional/Governmental Schools; City facilities Potable 357 Landscape City landscape irrigation Potable 917
Other Unbilled unmetered
consumption Potable 12
Distribution System Water Loss Potable 464
Subtotal Potable 5,207
Subtotal Non-Potable 0
Total 5,207
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: Volume of Water Loss for 2025 was estimated based on water supplied and billed meter data and has not been audited. The "Other" water use category accounts for unbilled unmetered

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water consumption and is estimated as 0.25% of the total billed consumption, in accordance with the AWWA water loss audit form.

4.2.5 Projected Water Use
Legal Requirements:

CWC Section 10631(d):
(1) For an urban retail water supplier, quantify, to the extent records are available, … projected water use, based upon information developed pursuant to subdivision (a), identifying the uses among water use sectors…
CWC Section 10633 (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...

CWC 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.

Water Code Section 10631:
(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…
If a Retail Supplier receives water from a Wholesale Supplier, the Retail Supplier must provide their projected use of that supply to the Wholesale Supplier. Suppliers will report which wholesale suppliers were informed of their projected use using Submittal Table 2-4 R.

CWC Section 10631(d)(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.

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Projected buildout water use is based on information developed in the Water Master Plan and the City’s Specific Plans I, II, and III., which reflects approved land use designations and dwelling unit projections at buildout. Buildout is anticipated to occur in 2040. Projected water demand presented in this section is provided in five-year increments through 2050, representing a 25-year planning horizon, and includes additional annual demand estimates for 2026 through 2030. Because buildout is expected in 2040, projected demands in 2045 and beyond are assumed to be equal to 2040 buildout demands. The City assumes a consistent growth rate from 2025 through the projected buildout year.

Table 4-3 (DWR Table 4-2 Retail) summarizes the projected water use by type for 2030 through 2050.

These projections were developed using the following assumptions:
• Population projections presented in Table 3-2 (DWR Table 3-1 Retail); and • Future water use distribution by category remains consistent with 2025 percentages.

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Table 4-3 – Total Uses of Potable and Non-Potable Water – Projected (DWR Table 4-2 Retail) Submittal Table 4-2 Retail: Total Uses for Potable, and Non-PotableWater — Projected Water Code Section 10631(d)(1)
Use Type
Additional
Description
(as needed)
Projected Water Use
(Report To the Extent that Records are Available)
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 2035 2040 2045 2050
opt
Add additional rows as needed.

Single Family Potable 3,180 3,520 3,897 3,897 -
Multi-Family Potable 561 621 688 688 -
Commercial
Builder;
Commercial;
Utilities;
Construction;
Manufacturing;
Mining
Potable 86 95 105 105 -
Institutional/Governmental Schools; City
facilities Potable 396 438 485 485 -
Landscape City landscape
irrigation Potable 1,015 1,123 1,243 1,243 -
Other
Unbilled
unmetered
consumption
Potable 13 14 16 16 -
Distribution System Water
Loss Potable 513 568 629 629 -
Subtotal Potable 5,764 6,381 7,063 7,063 0
Subtotal Non-Potable 0 0 0 0 0
Total 5,764 6,381 7,063 7,063 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. NOTES: Similar to projected population increases, the projected water use values are based on the same population percentage increase of 2.054 percent every year. The "Other" water use category accounts for unbilled unmetered water consumption and is estimated as 0.25% of the total billed consumption, in accordance with the AWWA water loss audit form.

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4.2.6 Water Use for Lower Income Households
Legal Requirements:

CWC Section 10631.1:
(a) The water use projections required by Section 10631 shall include projected water use for singlefamily 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 Section 65589.7 of the Government Code to grant a priority for the provision of service to housing units affordable to lower income households.

California Health and Safety Code Section 50079.5 (a):
“Lower income households” means persons and families whose income does not exceed the qualifying limits for lower income families… In the event the federal standards are discontinued, the department shall, by regulation, establish income limits for lower income households for all geographic areas of the state at 80 percent of area median income, adjusted for family size and revised annually.

The City has included an estimation of water demand for low-income housing in this plan, as indicated in Table 4-4 (DWR Table 4-3 Retail). This section includes a discussion of projected water use for low-income households in the City’s service area.

Table 4-4 – Inclusion in Water Use Projections (DWR Table 4-3 Retail) Submittal Table 4-3 Retail: Inclusion in Water Use Projections Water Code Section 10631 (a), 10631 (d)(4)(A), and 10631 (d)(4)(B) Are Future Water Savings Included in Projections?
Drop down list (y/n)
Yes
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.
4-7
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. 4-9 DWR NOTES: Additional guidance is provided in Appendix K.

NOTES: No additional notes.

SB 1087 approved on October 7, 2005 added certain provisions to the Government Code and amended a portion of the UWMPA. As it relates to the UWMPA, SB 1087 requires the water use projections of a

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UWMP to include the projected demands for single-family and multi-family residential housing needed for lower income households as identified in the housing element of any city or county in the service area of the supplier (CWC § 10631(a).) A lower income household is any household that has an income below 80 percent of the area median income, adjusted for family size.

U.S. Census data from the 2024 American Community Survey 5-Year Estimates Table S2503 indicate that in 2025 approximately 8,052 residents, assuming 3.8 persons per household, live in lower income households in the City [6]. Lower income is calculated as being 80% of the median income. Projected water demands associated with lower income residential water users through year 2045 are presented in Table 4-5. The projections assume the proportion of lower income residents to total residents remains constant for 2025 and beyond.

Table 4-5 – City of Mountain House Low Income Projected Water Demand Description
Year
2025 2030 2035 2040 2045
Total water use, AF a 5,207 5,764 6,381 7,063 7,063
Total population b 28,795 31,876 35,286 39,062 39,062
Lower income population c 8,052 8,914 9,867 10,923 10,923 Lower income water demand, AF 1,612 1,612 1,784 1,975 1,975 a) Total water use is from Table 4-2 and 4-3
b) Total population is from Table 3-2
c) Lower income population estimated using US Census Bureau, American Community Survey, Table S2503 data for 2024. Ratio of lower income population to total population was assumed to be the same for 2025 through 2045.

4.2.7 Climate Change Considerations
Legal Requirements:

CWC 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.

CWC Section 10635(b):

Every urban water supplier shall include, as part of its urban water management plan, a drought risk assessment … (and) shall include each of the following… (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.

The sections below discuss how climate change may impact the City’s water supplies. • Water Demand: Hotter days and nights, as well as a longer irrigation season, will increase landscaping and irrigation water needs, and industrial processes will have increased cooling water needs. Peak water demands may also be impacted.
• Natural Disaster: Natural disasters are expected to become more frequent as climate change brings increased climate variability, resulting in more extreme droughts and floods. This will challenge water supplier operations in several ways as wildfires are expected to become larger

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and hotter, droughts will become deeper and longer, and floods can become larger and more frequent.

Although the future water demand projections presented in this Plan do not explicitly incorporate climate change impacts, the City is well positioned to mitigate potential increases in demand. Much of the service area has been developed with water-efficient fixtures, appliances, and landscapes, and water conservation continues to be an integral component of local planning and development practices.

Climate change may also contribute to more frequent and prolonged drought conditions, which in turn could affect the availability and reliability of water supplies. A more detailed discussion of climate change impacts on water supply and supply reliability is provided in Chapters 6 and 7 of this Plan.

4.3 Distribution System Water Loss
Legal Requirements:

CWC Section 10631(d)(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 the distribution loss standards enacted by the board pursuant to Section 10608.34.

The last five years of water loss audit reporting submittals are summarized in Table 4-6 (DWR Table 4-5 Retail). The water loss audits for 2020-2023 are in Appendix D.

Table 4-6 – Water Loss Audit Reporting (DWR Table 4-5 Retail) Submittal Table 4-5 Retail: Water Loss Audit Reporting
Water Code Section 10631(d)(3)(A)
Public Water System ID #
Reported in Table 2-1 R
Reporting
Period
Submitted to DWR Water Loss
Audit Program (yes/no)
Report submittal status for all five years for each Public Water System as available.

Add rows as needed
CA3910027
2020 Yes
2021 Yes
2022 Yes
2023 Yes
2024 No
DWR NOTES: Suppliers will provide a link to the WUEdata submittals of their Water Loss Audit Reports.

NOTES: Water Loss Audits provided in Appendix D.

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4.4 Progress Toward Meeting the Water Loss Performance Standard Pursuant to Water Code Section 10631(d)(3)(C), the City is required to provide data demonstrating whether the City met its State Water Board Water Loss Performance Standard in 23 CCR Section 980.

The Water Loss Performance Standard does not have to be met until 2028. However, Water Code Section 10631(d)(3)(C) still requires that the City includes data in its 2025 UWMP to show whether it met the requirement. Table 4-7 (DWR Table 4-6 Retail) provides an overview of the City’s progress towards meeting the 2028 water loss standards.

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Table 4-7 – Progress Towards 2028 Water Loss Standard (DWR Table 4-6 Retail) Submittal Table 4-6 Retail: Progress Towards 2028 Water Loss Standard Water Code Section 10631(d)(3)(C) Public Water
System ID #
Reported in
Submittal Table
2-1 R
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 Apparent Water Loss
State Water Board Standard
Most Recent AWWA Water Loss
Audit
Real
Water Loss
Per Unit
per Day
State Water Board Standard Most Recent AWWA Water Loss Audit Apparent
Water Loss Per
Unit per Day
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)
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)
(AF)
Add additional rows as needed.

CA3910027 Yes 15.87
Gallons per
Service
Connection
per Day
(GPSCD)
7,818 151,85 17.34 54.12
Gallons per
Service
Connection
per Day
(GPSCD)
7,818 607.40 69.36
Water Board's Calculated Water Loss Standards
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. NOTES: The Fiscal Year 2024 Water Loss Audit, which is currently being prepared, was used to document the number of service connections, as well as real and apparent water losses.

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5 SB X7-7 Baselines, 2020 Targets, and 2025 Reporting
With the adoption of the Water Conservation Act of 2009, also known as SB X7-7, the State of California was required to reduce urban per capita water use by 20 percent by the year 2020 (i.e., “20 by 2020”).

CWC Section 10608.16(a) states: “The state shall achieve a 20-percent reduction in urban per capita water use in California on or before December 31, 2020.” To achieve this statewide objective, the California Legislature required each urban retail water supplier subject to the UWMPA to develop an urban water use target to help the state collectively achieve a 20-percent reduction.

This chapter provides a description of the methodology used to calculate the City’s compliance with SB X7-7 requirements.

5.1 Baseline and Target Calculations for 2025 UWMPs
Legal Requirements:

CWC 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.

CWC Section 10608.12:
(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 The City is required under the CWC to report its progress toward achieving the 2020 water use reduction target. In its 2020 UWMP, the City established SB X7-7 baselines and a 2020 target of 217 gallons per capita per day (gpcd). The City met this target in 2020.

Table 5-1 (DWR Table 5-1 Retail) summarizes the targeted water use value as well as the actual water use in 2020 to confirm the target was achieved.

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Table 5-1 – SB X7-7 2020 Target Progress (DWR Table 5-1 Retail) Submittal Table 5-1 Retail: SB X7-7 2020 Target Progress Water Code Section 10608.40
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.

Was Supplier
part of a
merger or
consolidation
since 2020?
Regional
Alliance
Target or
Individual
Target?
Drop down
list
2020 Target Actual
2020 GPCD
Did
Supplier
Achieve
Targeted
Reduction
for 2020?
Only for suppliers that did
not meet the Target in 2020
See DWR NOTES below.

Actual 2025
GPCD
(From SB X7-
7 Compliance
Form)
Did Supplier
meet the
2020 Target
in 2025?
No Individual 217 170 Yes NA
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
NOTES: 2020 Target GPCD value was met in 2020. 2025 GPCD is not needed to be analyzed.

5.2 Funding Eligibility
Legal Requirements:

CWC Section 10608.56:

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.

The City has met the 2020 Target and is therefore eligible to receive water-related grants or loans from the State of California.

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6 Normal-Year Water Supply Characterization
Legal Requirements:

CWC Section 10631(b):

Identify and quantify, to the extent practicable, the existing and planned sources of water available to the supplier as described in subdivision (a) [in five-year increments to 20 years or as far as data is available] 1, 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 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.

CWC 10631 (h):
... 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).

The UWMPA requires that the UWMP include a description of the agency’s existing and future water supply sources for the next 20 years. This chapter will provide the following information:
• Existing and planned sources of water;
• Projections of the water supplies over five-year increments through 2045; • Description of anticipated availability under normal, single dry, and five-year droughts; • Description of the management of each supply in correlation; and • Description of information pertinent to the reliability of the supplies, including considerations for climate change effects.

6.1 UWMP Water Supply Characterization
The following sections of this chapter discuss the varying water supply availability based on the supply type which includes:
• Purchased or Imported Water
• Groundwater
• Surface Water
• Stormwater

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• Wastewater and Recycled Water
• Desalinated Water
• Water Exchanges and Transfers
• Supply from Storage
• Other Water Supplies
• Future Water Projects

6.1.1 Purchased or Imported Water
In 1996, BBID entered into a Water Services Agreement with the City of Mountain House to provide 9,413 AFY of raw water to the Mountain House community (Appendix E). This volume reflects the quantity historically conveyed to and consumed within the City’s project area for agricultural purposes between 1976 and 1991. In October 2009, the City secured an additional 400 AFY from BBID, increasing the total contracted supply to 9,813 AFY. The agreement further states that BBID may make additional short-term supplies available to the City beyond the contracted amount to meet temporary increases in demand.

BBID’s primary source of supply is surface water diverted from the Sacramento–San Joaquin Delta.

Although BBID holds a pre-1914 appropriative water right authorizing the reasonable and beneficial use of up to 60,000 AFY, BBID voluntarily limits annual diversions to 50,000 AFY at a maximum diversion rate of 300 cubic feet per second under an agreement with DWR. Water for the City is diverted from an intake along the California Aqueduct located between Clifton Court Forebay and the State Water Project’s (SWP) Harvey O. Banks Pumping Plant.

BBID delivers water on a wholesale basis through its transmission system. Water diverted for the City is conveyed via a dedicated pump station and transmission main. In addition to serving the City, BBID provides water to the Mariposa Energy Project, the Contra Costa County Airport, and agricultural users in Contra Costa, Alameda, and San Joaquin counties.

6.1.2 Groundwater
Legal Requirements:

CWC Section 10631(b)(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. 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

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groundwater conditions in accordance with a groundwater sustainability plan or alternative adopted pursuant to Part 2.74 (commencing with Section 10720).
(C) 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. (D) A detailed description and analysis of the amount and location of groundwater that is projected to be pumped by the urban water supplier. The description and analysis shall be based on information that is reasonably available, including, but not limited to, historic use records.

As shown in Table 6-1 (DWR Table 6-1 Retail), the City does not currently utilize groundwater as a potable water supply source. However, since the 2020 UWMP, the City has reviewed alternative emergency supply options and believes that the most prominent solution, in case BBID is no longer able to supply water, would be groundwater. Per this discussion, the City currently has plans to implement groundwater as a permanent emergency supply of potable water as part of an Aquifer Storage and Recovery (ASR) Well System. Although mentioned here, further explanation on this future project is provided in Section 6.1.7 as it will primarily be used for emergency purposes and not for consistent use.

Table 6-1 – Groundwater Volume Pumped (DWR Table 6-1 Retail) Submittal Table 6-1 Retail: 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.

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 2022 2023 2024 2025
Add additional rows as needed

Total 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.

NOTES: City does not incorporate groundwater into their water usage.

A privately owned well, Shea Homes #1 Well, is located in the City’s service area and serves as a private well for construction water supply. Water pumped from Shea Homes #1 Well is not used by the City for urban water supply and is not considered an urban water supply for the purposes of this plan.

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6.1.3 Surface Water
According to the City’s Water Master Plan, several of the City’s properties, included in the Specific Plan II area, located north of Byron Road hold riparian water rights, which allow for the beneficial use of surface water from Old River. Because these properties remain undeveloped at this time, the City does not presently divert water pursuant to these rights. The City is currently coordinating with the Mountain House Mutual Water Company on a draft agreement under which the Company would retain ownership of the riparian rights while designating the City as its exclusive agent to exercise those rights on behalf of the Riparian Lots.

Upon development of these properties, the City anticipates utilizing the riparian water to meet on-site demands which are currently estimated to be up to a total of 2,570 AFY upon Buildout. The water may be applied directly as an untreated supply to the proposed ponds North of Byron Road or conveyed through the BBID diversion facilities, as previously described, for treatment and distribution as potable water serving the developed properties.

Water demand for the riparian properties at buildout is currently projected to be approximately 2,570 AFY.

6.1.4 Stormwater
The City does not currently retain stormwater for purposes of offsetting its potable water supply.

However, the City incorporates stormwater management and low impact development principles to reduce the impact of development on local water bodies.

The City is evaluating the development of small, local surface water storage reservoirs near Mountain House Creek to improve water supply reliability during dry periods. The proposed concept would capture and store stormwater runoff for later use, with potential total storage of up to approximately 1,000 acrefeet implemented in phases. This project would provide additional operational flexibility, reduce vulnerability to supply interruptions, and strengthen the City’s overall water supply resilience.

6.1.5 Wastewater and Recycled Water
Legal Requirements:

CWC 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.
(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,

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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.

The City collects and treats wastewater at its wastewater treatment plant (WWTP), which is currently operated under a third-party contract with Inframark.

6.1.5.1 Recycled Water Coordination
Legal Requirements:

CWC 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…
As the City serves as both the potable water provider and the wastewater collection and treatment agency, coordination of any changes related to recycled water use would occur internally within the City and in consultation with the contracted operators of the water and wastewater treatment systems.

Additionally, any future use of recycled water for irrigation purposes would require prior written approval from BBID, consistent with the terms of the City’s water supply agreement with BBID.

At present, the City is preparing a Wastewater Change Petition (WWCP) for a planned water reuse project associated with their Phase III Wastewater Treatment Plant Upgrade. As part of broader efforts to improve water use efficiency and better manage water resources, the City intends to reuse treated wastewater in a manner that will reduce discharges to downstream waterways.

The recycled water will flow by gravity through the natural channel of Old River and will ultimately be diverted at the BBID intake pump station. From there, the water would otherwise continue toward Clifton Court Forebay. The project documentation includes a schematic illustrating the flow path from the WWTP discharge point to Clifton Court Forebay. Further evaluation and filing of the required WWCP will be conducted in the future.

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6.1.5.2 Wastewater Collection, Treatment, and Disposal
Legal Requirements:

CWC Section 10633(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.

The City owns and operates the wastewater collection, treatment, and disposal facilities serving the entire community. At full buildout, it is anticipated that approximately 80 percent of the service area will convey wastewater to the WWTP via gravity through a backbone collection system, while the remaining 20 percent will require conveyance by lift stations and force mains.

The City’s WWTP is located on the eastern side of the service area. Wastewater flows generally from the Northwest toward the Southeast and from the Southwest toward the Northeast. As some portions of the Northern collection system will be located at elevations below the WWTP, sewer pump stations will be required to convey flows from these areas. Current sewer pipeline diameters within the collection system range from 8 inches to 24 inches.

The City has recently completed construction of modifications and improvements to the WWTP to improve treatment reliability and production of effluent quality that meets Title 22 recycled water applications. The WWTP improvements included installation of new headworks with fine screens to protect new Membrane Bioreactors (filters) and new biosolids handling. With these adjustments, the WWTP has removed the use of sequencing batch reactors, cloth filters, and decanters.

The City’s existing WWTP consists of influent pumping, flow measurement, fine screening, grit removal, emergency storage, MBR process for biological treatment and filtration, UV disinfection, effluent pumping, effluent disposal, chlorine residual addition, solids handling, and two lined aerated storage reservoirs.

The existing WWTP, after the most recent adjustments, has a permitted and design flow of 5.4 MGD to accommodate population growth.

The City’s WWTP discharges tertiary treated effluent to Old River under National Pollutant Discharge Elimination System (NPDES) Permit No. CA0084271. The permit was originally adopted under Order R5- 2023-0033 and later amended by Order R5-2025-0050, resulting in amended Order R5-2023-0033-01. The current permit authorizes an average dry weather flow of up to 5.4 MGD after the City demonstrated compliance with applicable permit conditions. The permit establishes effluent limitations and receiving water protections for Old River, including requirements for BOD, TSS, ammonia, nitrate plus nitrite, pH, disinfection performance, and temperature.

Tables 6-2 (DWR Table 6-2 Retail) summarize wastewater flow volumes collected within the service area during 2025.

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Table 6-2 – Wastewater Collected within Service Area (DWR Table 6-2 Retail) Submittal Table 6-2 Retail: Wastewater Collected Within Service Area Water Code Section 10633(a)
Check the box if there is no wastewater collection system.

Proceed to the next table.

Percentage of 2025 service area served by wastewater collection system (OPTIONAL)

Percentage of 2025 service area population served by wastewater collection system (OPTIONAL)
Wastewater Collection Recipient of Collected Wastewater Name of Wastewater
Collection Agency
Wastewater
Volume
Metered or
Estimated?

OPTIONAL
Drop Down List
Volume of
Wastewater
Collected
from UWMP
Service Area
2025
Name of Wastewater
Treatment Plant (WWTP)
and Place ID Number
Drop down list
Is WWTP
Located
Within UWMP
Area?
Drop Down List
Add additional rows as needed
City of Mountain House Metered 1,843 Mountain House WWTP, Place ID 241598 Yes
Total Wastewater Received from UWMP
Service Area in 2025: 1,843
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.

NOTES: The City of Mountain House WWTP is currently operated under a third-party contract with Inframark.

The City’s volume of wastewater treated and disposed of in their service area is documented in Table 6-3 (DWR Table 6-3 Retail).

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Table 6-3 – Wastewater Treatment and Discharge within Service Area (DWR Table 6-3 Retail) Submittal Table 6-3 Retail: Wastewater Treatment and Outcomes Within UWMP Service Area Water Code Section 10633(a) Check the box if no wastewater is treated or disposed of within the UWMP service area.Proceed to the next table.

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
2025 Volume
of
Wastewater
Received
from UWMP
Service Area
(As Reported
in Submittal
Table 6-2 R )
Total
2025
Volume
of Water
Treated
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)
Treatment
Level
Drop down list
Volume
Treatment
Level
Drop down list
Volume
Treatment
Level
Drop down list Volume
Treatment
Level
Drop down list
Volume
Treatment
Level
Drop down list
Volume Name of other entity
Add additional rows as needed
Mountain House
WWTP, Place ID
241598
No 1,843 1,916 Tertiary 0 Tertiary 0 Tertiary 1,916 Tertiary 0 Tertiary 0 Total 1,843 1,916 0 0 1,916 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: Discrepancy between wastewater received and volume of water treated is due to the City’s WWTP receiving additional water to treat from outside the UWMP service area.

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6.1.5.3 Recycled Water System Description
Legal Requirements:

CWC Section 10633 (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.

The City currently disposes of all treated wastewater effluent through discharge to Old River. As highly treated wastewater is increasingly recognized as a valuable resource for reducing reliance on potable water supplies, the City intends to evaluate opportunities for the beneficial reuse of treated effluent to improve overall water supply reliability.

Recycled water could be produced at the existing wastewater treatment facilities, subject to regulatory requirements and system feasibility. As part of the planned evaluation, the City anticipates identifying potential recycled water demands, estimating associated volumes and timing, and developing a conceptual layout for a recycled water distribution system, including major pumping and storage components. The study will inform future planning and implementation of recycled water use within the service area.

6.1.5.4 Current, Potential, and Projected Recycled Water Uses Legal Requirements:

CWC Section 10633:
(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. (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.

The City does not currently produce and provide recycled water within its service area. As indicated above, the City plans to study the potential for recycled water within its service area. As part of this planned study, the potential uses, including their timing and volume will be identified.

Tables 6-4 (DWR Table 6-4 Retail) and 6-5 (DWR Table 6-5 Retail) show that the City does plan to use recycled water in the future but does not have any current data to provide in regard to expected use.

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Table 6-4 – Current and Projected Recycled Water Direct Beneficial Uses Within Service Area (DWR Table 6-4 Retail) Submittal Table 6-4 Retail: Recycled Water Direct Beneficial Uses Within Service Area Water Code Section 10633 (c)(e) 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.

Name(s) of Facility/ies Producing (Treating) the Recycled Water (OPTIONAL) : Name of Supplier Operating the Recycled Water Distribution System (OPTIONAL) : Supplemental Water Added in 2025 (volume) Include units (OPTIONAL) : Source of 2025 Supplemental Water (OPTIONAL) :

Use Type
Drop down list
Potable or Non-Potable
(after treatment if treated)
(OPTIONAL)
Drop down list
Additional Information
(as needed) 2025 2030 2035 2040 2045 2050
Potential Recycled Water Use
Volume Narrative page number (OPTIONAL)
Add additional rows as needed
0 Subtotal Potable 0 0 0 0 0 0 0
Subtotal Non-Potable 0 0 0 0 0 0 0
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.

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: No additional notes.

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Table 6-5 – 2020 UWMP Recycled Water Use Projection Compared to 2025 Actual (DWR Table 6-5 Retail)
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.

Use Type
Drop Down list
2020 Projection
for 2025
2025 Actual
Use
Add additional rows as needed

Total 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 reported in Submittal Table 2-3 Additional Guidance. See Appendix M, Section M.21 for detailed guidance on this table.

NOTES: No additional notes.

6.1.5.5 Actions to Encourage and Optimize Future Recycled Water Use Legal Requirements:

CWC 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… and shall include the following:
(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.

As described in the previous sections, the City intends to evaluate the feasibility of recycled water use within its service area. While the initiation of this evaluation has been anticipated, the study has not yet been completed. As a result, the City has not identified potential recycled water demand volumes or specific opportunities for recycled water use at this time.

Accordingly, no increase in recycled water usage is currently projected, as reflected in Table 6-4 (DWR Table 6-4 Retail). Upon completion of the recycled water evaluation, the City will update its estimates and revise Table 6-4 (DWR Table 6-4 Retail) as appropriate in a future UWMP, anticipated to be in 2030.

Table 6-6 (DWR Table 6-6 Retail) shows the current methods in place to prepare to use recycled water in the future.

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Table 6-6 – Methods to Expand Future Recycled Water Use (DWR Table 6-6 Retail) 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.
6-9 Provide page location of narrative in the UWMP
Name of Action Description
Planned
Implementation
Year
Expected Increase in
Recycled Water Use
Add additional rows as needed
Plan for Recycled
Water
Prepare a Recycled Water
Feasibility Study and Master Plan 2026/2027 5,825
Total 5,825
Unit Conversion to AF 5,825
DWR NOTES:

Units of measure (AF, CCF, MG) 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.

The unit conversion to Acre Feet addresses the Water Code's requirement that this value be provided in acre-feet.

NOTES: No additional notes.

6.1.6 Desalinated Water Opportunities
Legal Requirements:

CWC Section 10631(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.

The City is located inland and does not have access to coastal waters; therefore, seawater desalination is not applicable and is not currently considered a technically or economically feasible water supply option.

Additionally, desalination of brackish surface water or groundwater is not presently required to meet municipal demands.

However, desalination could become a potential long-term consideration if salinity levels in the Sacramento–San Joaquin Delta increase to the point that Delta water is no longer suitable for municipal use. The Delta serves as a primary source of supply for both the Central Valley Project and the SWP.

Consequently, any salinity conditions that significantly impair municipal use of Delta supplies would also have widespread implications for water users throughout California, including a substantial portion of the State’s population. To properly mitigate this risk, the City has begun developing desalination ideas for this occurrence. Future UWMPs will elaborate on this development.

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6.1.7 Water Exchanges and Transfers
Legal Requirements:

CWC Section 10631(c):

Describe the opportunities for exchanges or transfers of water on a short-term or long-term basis.

The City does not currently participate in water transfers or exchange agreements with other water agencies. However, as part of long-term water supply planning, the City is planning to implement an ASR Well System to improve reliability. The ASR project would store treated surface water in an aquifer during wet periods and recover it during dry periods or when surface water deliveries are interrupted. The project is expected to provide up to 3,200 acre-feet of storage with a recovery capacity of up to 2,000 gallons per minute. Through its ongoing participation in the local Groundwater Sustainability Agency under the Sustainable Groundwater Management Act (SGMA), the City may evaluate opportunities for water banking or exchange within the Eastern San Joaquin Groundwater Basin during the planning horizon of this UWMP.

Historically, the City has utilized short-term emergency water supplies when necessary. In 2015, a portion of the City’s water demand was met through an emergency supply arrangement with the South San Joaquin Irrigation District (SSJID), following a temporary curtailment by the SWRCB of water deliveries to BBID. Legal and regulatory constraints affecting the City’s water supplies are further described in Chapter

7. The City is evaluating an emergency intertie with the City of Tracy to improve water supply redundancy, as recommended in the 2020 Potable Water System Master Plan Update. The City relies solely on BBID surface water, which has experienced curtailments and recurring summer pumping suspensions. A recent capacity and hydraulic evaluation found favorable conditions and supports a 12- to 16-inch intertie capable of delivering about 3,400 to 6,000 AF per year using existing infrastructure with limited operational changes.

6.1.8 Supply from Storage
The City does not currently use water from storage or underground storage as part of the City’s water supply.

6.1.9 Future Water Projects
Legal Requirements:

CWC Section 10631 (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.

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Table 6-7 (DWR Table 6-7 Retail) summarizes the City’s planned future water supply programs. As described in Section 6.1.3, the City intends to exercise its riparian water rights associated with properties located north of Byron Road as those properties are developed. These rights authorize the beneficial use of Old River surface water within the riparian parcels. At full buildout, the water demand associated with these properties is estimated to be approximately 2,570 acre-feet. The riparian supply is anticipated to be used either as untreated water to supply the proposed ponds north of Byron Road or conveyed through the BBID diversion facilities for treatment and potable water service.

As discussed in Section 6.1.7, the City is evaluating the feasibility of implementing an ASR program. In addition, as described in Section 6.1.5, the City plans to assess the potential for recycled water use within its service area including advanced treatment processes such as reverse osmosis to support future DPR opportunities. Under this concept, highly treated recycled water from the WWTF could potentially be conveyed to the planned ASR system for groundwater storage and later recovery. Because these water supply options remain conceptual and the associated studies have not yet been completed at the time of preparation of this UWMP, they are not included in Table 6-7 (DWR Table 6-7 Retail) or in the supply projections presented in Section 6.1.10.

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Table 6-7 – Expected Future Water Supply Projects or Program (DWR Table 6-7 Retail) Submittal Table 6-7 Retail: Expected Future Water Supply Projects or Programs Water Code Section 10631 (f)
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.

Procees to the next table.

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. 6-4 Provide page location of narrative in the UWMP
Name of
Future
Projects or
Programs
Joint Project with
other suppliers?
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)
Drop
Down
List
(yes/no)
If Yes,
Supplier
Name
Add additional rows as needed
Old River
Riparian
Rights
No Potable 2040 All Year
Types 2,570
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: No additional notes.

6.1.10 Summary of Existing and Planned Sources of Water This section describes the types of water that is supplied to the City and the quantity supplied by each water source.

6.1.10.1 Description of Supplies
Currently the City exclusively uses purchased/imported water. When the City develops the properties located North of Byron Road, the City will use the surface water from the Old River within the boundaries of the parcels the City holds riparian water rights to.

6.1.10.2 Quantification of Supplies
The actual (2025) water supplies for the City are summarized in Table 6-8 (DWR Table 6-8 Retail). The projected water supplies for the City are summarized in Table 6-9 (DWR Table 6-9 Retail).

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Table 6-8 – Water Supplies – 2025 Actual (DWR Table 6-8 Retail) Submittal Table 6-8 Retail: Water Supplies — 2025 Actual Water Code Section 10631 (b)
Water Supply
Additional Description
(as needed)
2025
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
NonPotable
(after
treatment if
treated)
(OPTIONAL)
Drop Down
list
Actual
Volume
Total
Entitlement
(OPTIONAL)
See "DWR Notes"
below
Add additional rules as needed
Purchased or Imported
Water BBID Potable 5,207
Subtotal Potable 5,207 0
Subtotal Non-Potable 0 0
Total 5,207 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.

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

NOTES: No additional notes.

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Table 6-9 – Water Supplier – Projected (DWR Table 6-9 Retail) Submittal Table 6-9 Retail: Water Supplies — Projected Water Code Section 10631 (b) Water Supply
Additional
Detail on
Water
Supply
Potable or Non-Potable
(after treatment if treated)
(OPTIONAL)
Drop Down list
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
2030 2035 2040 2045 2050 (opt)
Reasonably
Available
Volume
Total
Entitlement
(OPTIONAL)
See "DWR Notes"
below
Reasonably
Available
Volume
Total
Entitlement
(OPTIONAL)
See "DWR Notes"
below
Reasonably
Available
Volume
Total
Entitlement
(OPTIONAL)
See "DWR Notes"
below
Reasonably
Available
Volume
Total
Entitlement
(OPTIONAL)
See "DWR Notes"
below
Reasonably
Available
Volume
Total
Entitlement
(OPTIONAL)
See "DWR Notes"
below
Add additional rows as needed
Purchased or Imported
Water BBID Potable 9,813 9,813 9,813 9,813
Surface Water Riparian Rights Potable 2,570 2,570
Subtotal Potable 9,813 0 9,813 0 12,383 0 12,383 0 0 0
Subtotal Non-Potable 0 0 0 0 0 0 0 0 0 0
Total 9,813 0 9,813 0 12,383 0 12,383 0 0 0
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.

NOTES: No additional notes.

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6.1.11 Special Conditions
The City is expected to experience the effects of climate change within its service area. The BBID’s primary source of supply is the Delta, which is identified as a climate sensitive area in the Climate Change Handbook for Regional Water Planning. Other factors of climate change are expected to include increased minimum and maximum temperatures, seasonality of precipitation, extreme heat, heat wave duration, extreme precipitation events (including intensity and frequency), drought likelihood, and wildfire risk and area burned. These projected changes would likely increase peak demand, extreme events (e.g., landslides and flash flooding), and stress in native vegetation providing additional fuel for wildfires.

6.2 Energy Use
Legal Requirements:

CWC 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.

Water energy intensity represents the total amount of energy expended, calculated on a whole-system basis, to deliver water to customers. Energy intensity is expressed in kilowatt-hours per acre-foot and reflects the energy required to convey water from its source through treatment and distribution to the point of delivery. Evaluating whole-system energy intensity enables the City to make informed decisions in managing its water supplies and operating its facilities, including:
• Identifying opportunities to reduce energy consumption; • Estimating energy savings and greenhouse gas emission reductions associated with water conservation programs;
• Supporting applications for grants related to energy efficiency and water conservation initiatives; • Informing climate change mitigation and adaptation strategies; and • Benchmarking energy use across individual water supply, treatment, and distribution components and comparing performance with similar agencies.

Energy intensity was calculated using the tables provided by DWR. DWR Table O-1B was selected for reporting the water delivery product energy usage. The energy use tables for retail water delivery, wastewater, and recycled water are provided in Appendix F.

As discussed in Section 6.1.5, the City also provides wastewater collection and treatment services within its service area. However, because the City does not currently produce or distribute recycled water,

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energy intensity calculations associated with recycled water production and delivery are not applicable at this time.

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7 Water Service Reliability and Drought Risk Assessment The UWMPA requires that the UWMP address the reliability of the City's long term water supplies. This includes a description of supply constraints which may impact the supply. Also included is a comparison between the City’s supply and demand for a normal year, single-dry year, and five-consecutive year drought.

7.1 Constraints on Water Sources
Legal Requirements:

CWC Section 10631 (b)(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 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.

Water Code 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.

Water Code Section 10635 (b)(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.

Water Code Section 10635 (b)(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.

Evaluating the reliability of the City’s water supply is complex due to a variety of factors that can affect water source availability and dependability. These factors may include legal issues, environmental constraints, water quality, and climatic variations.

7.1.1 Legal
On June 15, 2021, the SWRCB issued Notices of Water Unavailability pursuant to Resolution No. 2021- 0028 to all post-1914 appropriative water right holders within the Delta watershed, as well as to certain water users with more senior claims. The notices were prompted by severe drought conditions, including below-average surface water flows, reservoir storage, and snowpack, which were expected to persist into 2022.

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Under Resolution No. 2021-0028, BBID, and by extension the City, was subject to curtailment of Delta water diversions, except for diversions necessary to meet minimum human health and safety needs. As of preparation of this plan, BBID is challenging both Resolution No. 2021-0028 and the methodology employed by the SWRCB to determine water rights curtailments. While the outcome of this challenge remains uncertain, this UWMP conservatively assumes that the City’s supply from BBID may be subject to future reductions.

7.1.2 Environmental
Over its more than 100 years of operation, BBID has not experienced water supply curtailments due to environmental constraints, and no such constraints are anticipated through the UWMP planning horizon of 2045.

7.1.3 Water Quality
BBID has not historically experienced water supply curtailments related to water quality. The City treats all delivered water supplies in compliance with applicable federal and State drinking water standards and annually reports water quality results to its customers through a Consumer Confidence Report. The 2024 Consumer Confidence Report is included as Appendix G and is also available on the City website.

A potential long-term water quality concern is the risk of Delta levee failure. Seismic damage to Delta levees could result in prolonged flooding of Delta islands, allowing saline water from San Francisco Bay to intrude into the Delta for an extended period. Such an event would have statewide implications, affecting tens of millions of Californians who rely on Delta supplies. In response, the City is evaluating alternative water supply projects and mutual aid agreements to provide water over a multi-year period in the event of a major Delta disruption. These efforts are discussed further in Section 7.2.3, although not all identified projects would fully address Delta salinity concerns.

7.1.4 Climatic Factors
Snowmelt from the Sierra Nevada has historically been a key source of high-quality water for the Delta.

However, over the past century, the proportion of precipitation falling as snow has declined. When precipitation occurs as rainfall rather than snowfall, runoff enters watersheds more rapidly and is not stored as snowpack for gradual release during the summer months. Historically, snowmelt provided a sustained source of high-quality water during the dry season; reductions in snowpack may therefore contribute to declining surface water quality in the Delta.

Persistent and severe dry hydrologic conditions were the primary drivers of water supply curtailments in both 2015 and 2021. Although uncertainty remains regarding future legal interpretations of curtailment authority, it is likely that similar hydrologic conditions will recur. The legal framework associated with these curtailments is discussed in Section 7.1.1.

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7.2 Water Service Reliability Assessment (WSRA)
Legal Requirements:

CWC 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.

Expected water service reliability pursuant to Section 10635 of the Water Code is assessed in the following sections.

7.2.1 WSRA Year-Type Characterization
This section addresses the reliability of the City’s water supply in average, single dry, and multiple dry water years. The City uses the following water year definitions from the UWMP Guidebook:
• Normal Year: a year, or an averaged range of years, that most closely represents the average water supply available to the agency. For the purposes of this UWMP, the terms “normal” and “average” are used interchangeably.
• Single-Dry Year: the year that represents the lowest water supply available to the agency. • Five-Consecutive-Year Drought: the driest five-year historical sequence for the Supplier (Water Code Section 10612).

Table 7-1 (DWR Table 7-1 Retail) shows the basis of water year data as a percentage of average supply.

The base years were selected using rainfall data provided by the CIMIS.

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Table 7-1 – Basis of Water Year Data (DWR Table 7-1 Retail) 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: [insert location from UWMP]
Quantification of available supplies is provided in this table as either volume only, percent only, or both.

Volume Available % of Average Supply
Average Year 2014 9,813 100%
Single-Dry Year 2015 1,647 17%
Consecutive Dry Years 1st Year 2012 9,813 100%
Consecutive Dry Years 2nd
Year 2013 9,813 100%
Consecutive Dry Years 3rd
Year 2014 9,813 100%
Consecutive Dry Years 4th
Year 2015 1,647 17%
Consecutive Dry Years 5th
Year 2016 9,813 100%
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.

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

NOTES: In an average year, the volume available is assumed to equal the contractual amount available to the City from BBID. In 2015, which represents the single-dry year and the fourth year of a five-year drought, BBID delivered 17 percent of the contractual amount due to the 2015 curtailment order.

BBID pumping was curtailed in 2015, representing the City’s most severe single dry year on record.

According to the City’s 2015 Urban Water Management Plan, BBID delivered approximately 1,647 acrefeet of raw water to the City during that year, which equates to about 17 percent of the contracted supply of 9,813 AFY.

For planning purposes, this same level of reduced delivery is assumed to occur during the fourth year of a five-year drought sequence, consistent with conditions experienced during the 2012-2016 drought.

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7.2.2 Service Reliability – Supply and Demand Comparison Legal Requirements:

CWC 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.

The water service reliability for a Normal Year, Single-Dry Year, and Multiple Dry Years is discussed in the following sections.

7.2.2.1 Water Service Reliability – Normal Year
At buildout (2040), the City’s water demands are projected to equal 7,063 AFY. The 2020 Water Master Plan identified available supplies of purchased water from BBID and approximately 2,570 AFY of riparian supply from properties adjacent to Old River.

As shown in Table 7-2 (DWR Table 7-2 Retail), the City’s Normal Year supplies are adequate to meet projected Normal Year demands through 2045.

Table 7-2 – Normal Year Supply and Use Comparison (DWR Table 7-2 Retail) Submittal Table 7-2 Retail: Normal Year Supply and Use Comparison Water Code Section 10635 (a)
2030 2035 2040 2045 2050
(Opt)
Supply totals
(autofill from Submittal
Table 6-9 R)
9,813 9,813 12,383 12,383 0
Use totals
(autofill from Submittal
Table 4-2 R)
5,764 6,381 7,063 7,063 0
Surplus/(shortfall) 4,049 3,432 5,320 5,320 0
DWR NOTES : Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3.

NOTES: Volumes are in AF. Beginning in 2040, the City can utilize its Old River riparian rights (2,570 AFY).

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7.2.2.2 Water Service Reliability – Single-Dry Year
The City’s available water supplies under a single-dry year scenario consist of approximately 1,647 AFY from BBID deliveries and, beginning in 2040, an additional 2,570 AFY associated with the beneficial use of Old River riparian water rights.

As shown in Table 7-3 (DWR Table 7-3 Retail), the City’s Single-Dry Year supplies are insufficient to fully meet projected Single-Dry Year demands through the year 2045.

Table 7-3 – Single-Dry Year Supply and Demand Comparison (DWR Table 7-3 Retail) Submittal Table 7-3 Retail: Single Dry Year Supply and Use Comparison Water Code Section 10635(a)
2030 2035 2040 2045 2050 (Opt)
Supply totals 1,647 1,647 4,217 4,217 -
Use totals 5,764 6,381 7,063 7,063 -
Surplus/(shortfall) (4,117) (4,734) (2,846) (2,846) 0
DWR NOTES : Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3.

NOTES: Beginning in 2040, the City of Mountain House can utilize its Old River riparian rights (2,570 AFY).

To address anticipated supply shortfalls during single-dry year conditions, the City may implement one or more water shortage response actions, including declaration of a water shortage stage as described in Chapter 8. In parallel, the City and BBID are evaluating additional water supply and management strategies, such as increased storage capacity, recycled water development, and emergency interties, to improve drought resilience. These potential measures are discussed further in Section 7.2.3.

7.2.2.3 Water Service Reliability – Multiple Dry Years
Based on conditions observed during the 2012–2016 drought, the City’s water supplies under a multiple dry year scenario are assumed to experience reductions only during the fourth year of a five-year drought sequence. As previously mentioned, beginning in 2040, the City anticipates supplementing its water supply with approximately 2,570 AFY from the beneficial use of Old River riparian water rights.

As shown in Table 7-4 (DWR Table 7-4 Retail), available supplies under multiple dry year conditions are sufficient to meet projected water demands through 2050, with the exception of the fourth year of each five-year drought period. In the event of supply shortfalls during these periods, the City may implement water shortage response measures, including declaration of a water shortage stage as described in Chapter 8.

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In addition, the City and BBID are evaluating a range of supplemental supply and water management strategies such as expanded storage, recycled water development, and emergency interties to improve long-term drought resilience. These potential measures are discussed further in Section 7.2.3.

Table 7-4 – Multiple-Dry Years Supply and Demand Comparison (DWR Table 7-4 Retail) Submittal Table 7-4 Retail: Multiple Dry Years Supply and Use Comparison Water Code Section 10635(a)
2030 2035 2040 2045 2050
(Opt)
First year
Supply totals 9,813 9,813 12,383 12,383 -
Use totals 5,764 6,381 7,063 7,063 -
Surplus/(shortfall) 4,049 3,432 5,320 5,320 0
Second year
Supply totals 9,813 9,813 12,383 12,383 -
Use totals 5,764 6,381 7,063 7,063 -
Surplus/(shortfall) 4,049 3,432 5,320 5,320 0
Third year
Supply totals 9,813 9,813 12,383 12,383 -
Use totals 5,764 6,381 7,063 7,063 -
Surplus/(shortfall) 4,049 3,432 5,320 5,320 0
Fourth year
Supply totals 1,647 1,647 4,217 4,217 -
Use totals 5,764 6,381 7,063 7,063 -
Surplus/(shortfall) (4,117) (4,734) (2,846) (2,846) 0
Fifth year
Supply totals 9,813 9,813 12,383 12,383 -
Use totals 5,764 6,381 7,063 7,063 -
Surplus/(shortfall) 4,049 3,432 5,320 5,320 0
DWR NOTES: Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3.

NOTES: Volumes are in AF. Beginning in 2040, the City can utilize its Old River riparian rights (2,570 AFY).

7.2.3 Description of Management Tools and Options
Legal Requirements:

CWC Section 10620(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.

Due to the City relying heavily on imported Delta water supplies, it is actively evaluating a range of water management and supply options to improve reliability during dry and critically dry years. Following the 2015 curtailment, the City entered into an emergency short-term water supply agreement with SSJID through December 31, 2015. Although the agreement ultimately was not utilized after the SWRCB lifted the curtailment in September 2015, it provided an important contingency supply option.

The City continues to investigate additional long-term and emergency water supply strategies, including development or purchase of recycled water, construction of an intertie pipeline with the City of Tracy,

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and potential conveyance associated with a future ASR well located east of Mountain House. In addition, the City is evaluating the future beneficial use of its Old River riparian water rights, which may be utilized as a local supply or conveyed through the Delta and diverted at the BBID diversion facilities for delivery to Mountain House.

Implementation of certain dry-year supply options may require near-term capital or operational expenditures. To ensure financial readiness for emergency water supply conditions, the City established a restricted Drought Mitigation Fund in March 2016 with an initial allocation of $200,000. Funds are contributed to the Drought Mitigation Fund annually and are reserved specifically to address emergency water supply needs, such as those experienced during the 2015 drought. The City periodically evaluates potential supply deficits and estimated procurement costs to confirm that the fund remains adequate.

Mountain House is a relatively new community designed to incorporate high levels of water efficiency. As development continues, water conservation practices and water-efficient landscaping and plumbing fixtures are implemented in accordance with current regulatory requirements to minimize reliance on imported water supplies. The City’s water demand management and conservation programs are described in Chapter 9 of this plan.

7.3 Drought Risk Assessment
Legal Requirements:

CWC 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.

CWC Section 10635(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 in the urban water management plan. The urban water supplier may conduct an interim update or updates to this drought risk assessment within the five-year 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.

This section provides a Drought Risk Assessment (DRA) based on the five driest consecutive years on record and plausible changes in climate, regulations, and other locally applicable criteria. A description of

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the data and methods used, basis for the supply shortage conditions, determination of the reliability of each source, and comparison of total water supplies and uses during a drought are provided below.

7.3.1 DRA Data, Methods, and Basis for Water Shortage Conditions The data used for the DRA include historical imported delivery records for the period 2012 through 2016, which represents the driest five-year sequence on record for the City, as well as other historical operational and system performance records. Imported water production data from the BBID were evaluated in supply availability, system reliability, and operational performance during drought conditions, and to determine whether drought-related supply constraints affected the City’s water supply.

This evaluation focused on identifying historical reductions in imported water deliveries during extended drought conditions and assessing the City’s ability to meet water demands under such circumstances.

Additional information regarding BBID’s supply obligations, operational constraints, and delivery conditions is provided in the BBID Water Services Agreement, included as Appendix E.

7.3.2 DRA Water Source Reliability
Historical imported water delivery data from 2012 through 2016 indicates that BBID water supplies were adversely affected during the five-year drought period, with the most significant reduction occurring in the fourth year when deliveries to the City were substantially curtailed. Although no droughts of similar severity have occurred since that time, this experience highlighted the City’s vulnerability to prolonged reductions in imported water supplies.

In response, the City has evaluated alternative water supply options to improve system reliability during drought conditions. While the City does not currently utilize groundwater as a potable water supply source, groundwater has been identified as the most viable emergency supply option should imported water deliveries become constrained. The City anticipates developing groundwater infrastructure as a permanent emergency potable water supply within the next three to four years, though no confirmed groundwater development projects are planned within the UWMP planning horizon.

In addition, the City holds riparian water rights associated with properties located north of Byron Road within the Specific Plan II area. Upon future development, these rights may allow for the beneficial use of surface water from Old River to meet on-site demands, which are currently estimated at approximately 2,570 acre-feet per year at buildout. Together, these measures are intended to enhance the City’s water supply reliability and reduce vulnerability to future drought conditions.

7.3.3 Total Water Supply and Use Comparison
The total water supply and use comparison is shown in Table 7-5 (DWR Table 7-5 Retail). The comparison indicates that the City currently does not have sufficient water supply to meet projected demands during a five-year drought and that water shortage conditions are projected during the five-year drought scenario evaluated. The WSCP further discusses measures for reducing water demands with the implementation of water shortage conditions.

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Table 7-5 – Five-Year Drought Risk Assessment Tables (DWR Table 7-5 Retail) Submittal Table 7-5 Retail: Five-Year Drought Risk Assessment Water Code Section 10635(b)(3)
2026 Total
Total Water Use 5,314
Total Supplies 9,813
Surplus/Shortfall w/o WSCP Action 4,499
2027 Total
Total Water Use 5,423
Total Supplies 9,813
Surplus/Shortfall w/o WSCP Action 4,390
2028 Total
Total Water Use 5,534
Total Supplies 9,813
Surplus/Shortfall w/o WSCP Action 4,279
2029 Total
Total Water Use 5,648
Total Supplies 1,647
Surplus/Shortfall w/o WSCP Action (4,001)
2030 Total
Total Water Use 5,764
Total Supplies 9,813
Surplus/Shortfall w/o WSCP Action 4,049
DWR NOTES: Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3.

NOTES: No additional notes.

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8 Water Shortage Contingency Plan
In response to the severe drought of 2012-2016, legislation was adopted in 2018 mandating that the UWMP include a WSCP that provides a detailed proposal for assessing water supply availability and response actions to water shortage conditions. The WSCP is to be a stand-alone document which will allow for amending the plan without amending the 2025 UWMP. The City WSCP is provided in Appendix H. Refer to the WSCP for the following DWR Tables:
• DWR Table 8-1: Cross-Reference for Standard vs Supplier Shortage Levels • DWR Table 8-2: Supply Augmentation and Other Actions
• DWR Table 8-3: Demand-Reduction Actions

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9 Demand Management Measures
This chapter describes the City’s historical and existing Demand Management Measures (DMMs) implemented to promote water conservation and reduce demands on available water supplies. The discussion includes past, current, and projected DMMs. These measures are a key component of the City’s long-term water supply planning and are also integral to the effectiveness of the WSCP, which is provided in Appendix H.

In prior UWMPs, water suppliers were required to provide extensive data documenting progress in implementing specific DMMs. However, AB 2067, enacted in 2014, simplified and updated DMM reporting requirements. The revised framework shifted the focus from detailed documentation of individual measures to implementation of core conservation actions designed to support compliance with the water use efficiency targets established under Senate Bill X7-7.

For retail water suppliers, the number of required DMMs was reduced to six standardized measures, along with an additional “other” category. Under the current requirements, agencies must provide a narrative description of the status of each DMM and explain how these measures contribute to achieving water efficiency goals; detailed quantitative data are no longer required.

The following sections summarize the City’s current and planned efforts to implement the applicable Demand Management Measures.

9.1 Water Conservation Program Overview
The City has a long-standing commitment to promoting water use efficiency through the implementation of comprehensive water conservation programs. Mountain House is a relatively new, master-planned community that has been developed with water-efficient plumbing fixtures and modern irrigation systems. The City’s overall water conservation strategy relies primarily on watering restrictions and prohibitions against water waste, as codified in the City’s Municipal Code of Ordinances Division 3 Chapter 2 (Appendix I). These regulatory measures are reinforced through an active public education and outreach program.

Through this integrated approach, the City encourages efficient water use among its customers while maximizing the benefits of its modern, water-efficient infrastructure. As a result of these efforts, the City achieved its 2020 SB X7-7 per capita water use target of 217 GPCD, as described in Chapter 5 of this plan.

In 2020, actual per capita water use within the City service area was approximately 170 GPCD.

9.2 Report Implementation

9.2.1 Implementation over the Past Five Years
All DMM discussed in Section 9.3 have been implemented over the past five years and are continuing to be implemented. The City is committed to programs designed to conserve and protect the quantity and quality of its surface water resource. The overall reduction of water and compliance with the SB X7-7 2020 target indicates that the programs adopted in the community have been effective.

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9.2.2 Implementation to Achieve Water Use Targets
Legal Requirements:

CWC Section 10631:
(e) Provide a description of the supplier’s water demand management measures. This description shall include all of the following:
(1)(A) …a narrative description that addresses the nature and extent of each water demand management measure implemented over the past five years.

As discussed in Chapter 5, the City has met the SB X7-7 2020 target. The City will continue to implement the above described DMMs to reduce water demands and protect the surface water supply.

9.3 Existing Demand Management Measures for Retail Suppliers Legal Requirements:

CWC Section 10631:
(e)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 measure 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.

In accordance with Urban Water Management Plan requirements, this plan addresses the following six DMMs:
• Water waste prevention ordinances
• Metering
• Conservation-oriented pricing
• Public education and outreach
• Programs to assess and manage distribution system real losses • Water conservation program coordination and staffing support In addition, the City is required to describe any other DMMs that have been implemented and have had a significant effect on water use within the service area.

This section describes both the DMMs currently in place and those planned for future implementation.

For each DMM, the discussion includes a description of the existing program, an overview of implementation activities during the previous five-year period, and a summary of planned future actions.

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9.3.1 Water-Waste Prevention Ordinances
The City enforces water waste prevention requirements throughout its service area. Division 3 Chapter 2 of the City’s Municipal Code of Ordinances, included as Appendix I, define prohibited uses of water and establish standards intended to promote efficient water use. The provisions of MMC Section 5-3-202, Conservation of Water, encourage conservation best practices at all times, with additional restrictions implemented during declared drought or water shortage conditions, as described in Chapter 8 of this plan.

The Municipal Code identifies a range of prohibited indoor and outdoor water use practices, including the indiscriminate use of water that results in runoff into streets or gutters. The City staff are authorized to enforce these requirements through measures such as administrative penalties, flow restrictions, and, if necessary, discontinuation of water service. The full water waste prevention code is available on the City’s website at: https://www.mountainhouseca.gov/.

The effectiveness of this Demand Management Measure is evaluated based on the number of reported or observed violations. Over the past five years, the City has not received any water waste complaints or recorded violations.

Implementation of this measure is ongoing. Although water savings associated with water waste prevention ordinances cannot be directly quantified, this measure is expected to support the City’s water use efficiency goals by discouraging nonessential water use and prioritizing water availability for critical needs such as human consumption, sanitation, and fire protection.

9.3.2 Metering
Legal Requirements:

CWC Section 526:
(a) Notwithstanding any other provisions of law, an urban water supplier that, on or after January 1, 2004, receives water from the federal Central Valley Project under a water service contract or subcontract... shall do both of the following:
(1) On or before January 1, 2013, install water meters on all service connections to residential and nonagricultural commercial buildings... located within its service area.

Water Code section 527
(a) An urban water supplier that is not subject to Section 526 shall do both the following:
(1) Install water meters on all municipal and industrial service connections located within its service area on or before January 1, 2025.

The City meters all customer connections in accordance with Municipal Code Section 5-3-114 and bills customers based on meter size, customer class (e.g., single-family residential or commercial), and the volume of water consumed. Universal metering supports accurate billing, encourages water use efficiency, and provides customers with direct feedback on their water consumption.

The City is currently upgrading its metering infrastructure by installing real-time transmitters as part of an Advanced Metering Infrastructure (AMI) system. All new development within Mountain House is required to install AMI-compatible meters. As of the preparation of this plan, approximately 94 percent of the existing service area has been converted to AMI technology.

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The AMI system is supported by EyeOnWater, a secure, cloud-based platform accessible online and via smartphone applications at no cost to customers. EyeOnWater allows customers to view near real-time hourly water use data, establish customized consumption thresholds, and receive automatic leak alerts.

The platform also evaluates water use patterns and provides month-to-month and year-over-year usage comparisons. These features enable customers to quickly identify abnormal water use, including leaks associated with subsurface irrigation systems, and take corrective action.

In addition to enhancing customer awareness, the AMI system improves the City’s ability to communicate with customers regarding water use and conservation opportunities. Implementation of this Demand Management Measure is expected to reduce overall water consumption within the service area by providing accurate, timely water use information to both customers and the City.

9.3.3 Conservation Pricing
The City completed a comprehensive Water and Wastewater Rate Study in 2017 (2017 Rate Study), which is summarized in Appendix J. The objectives of the 2017 Rate Study were to ensure that water and wastewater rates generate sufficient revenue to meet operational and maintenance costs, fund planned capital improvements, and establish and maintain appropriate financial reserves. One such reserve is the Water Utility Rate Stabilization and Drought Contingency Reserve, which is intended to mitigate potential revenue shortfalls resulting from reduced water sales during drought periods. Over the five-year ratesetting period established by the 2017 Rate Study, this reserve was projected to increase by approximately $250,000 per year.

The City customers are charged a monthly fixed service fee based on meter size and customer classification, in addition to a volumetric usage charge based on metered water consumption. Water use is billed in units of hundred cubic feet (HCF), where one HCF is equivalent to approximately 748 gallons.

Volumetric water rates are established based on wholesale water costs charged by BBID and the costs associated with water distribution within the City’s service area.

At the time of this plan, residential customers are billed a uniform volumetric rate of $1.0002 per HCF, while non-residential customers, including fire service meters, are billed a uniform rate of $1.0761 per HCF. The use of volumetric pricing provides a direct financial incentive for customers to reduce water consumption and adopt efficient water use practices.

Implementation of this Demand Management Measure supports the City’s water use efficiency objectives by ensuring that customers pay rates that reflect the true cost of providing water service. This approach helps adequately fund system operations, maintenance, repair and replacement programs, and ongoing water conservation efforts. The City will continue to evaluate the effectiveness of its rate structure by monitoring trends in unit water use in response to rate adjustments.

9.3.4 Public Education and Outreach
The City seeks to promote lasting, sustainable changes in water use behavior through an active public education and outreach program, rather than relying solely on short-term responses during drought conditions. These efforts are designed to increase customer awareness of water resource limitations, encourage efficient water use practices, and support compliance with local and State conservation requirements.

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9.3.4.1 Public Information
The City distributes water conservation information to customers and the general public through a variety of communication channels, including billing statement inserts, public presentations, telephone and email notifications, and newsletters. The monthly City newsletter provides updates on conservation goals, monthly and cumulative conservation performance, applicable State mandates, and current drought conditions. It also offers seasonally appropriate water-saving tips tailored to prevailing conditions.

In addition, the City maintains a dedicated water conservation section on its website that includes guidance on efficient indoor water use (e.g., kitchens, laundry areas, bathrooms, and offices) and outdoor water use (e.g., landscaping, lawn care, and swimming pools). Customers are encouraged to report water waste and leaks through online reporting tools available on the City website.

To supplement locally developed materials, the City also directs customers to SaveOurWater.com, a statewide water conservation resource funded by the Association of California Water Agencies and the California Department of Water Resources, for additional information and conservation tools.

9.3.4.2 Water Conservation Workshops
The City hosts Water Conservation Workshops, supported through California Department of Water Resources sponsorship, to educate customers about efficient water use practices, local water supply conditions, and statewide drought challenges. Topics presented during the October 2021 virtual Water Conservation Workshop included:
• Facts and statistics related to water use, water waste, and conservation • Evapotranspiration concepts and plant water requirements • City water use trends, water supply sources, and drought planning efforts • Instructions on reading water meters and enrolling in and using the EyeOnWater real-time water use platform for customers with AMI meters
• Methods for identifying and repairing residential irrigation system leaks and procedures for reporting water waste or leaks to the City
• Water-efficient landscape planning, including hydrozoning principles, efficient irrigation systems, irrigation system maintenance, smart irrigation controllers, and drought-tolerant plant selection Approximately 36 individuals attended the October 2021 virtual workshop, and an additional 97 viewers have accessed the recorded presentation via YouTube. The workshop recording is also available on the City website for ongoing reference.

9.3.4.3 Implementation
Public education and outreach activities are ongoing and are expected to support the City’s water use efficiency objectives by increasing customer understanding of the value of water, promoting efficient water use practices, and reducing water waste across the service area.

9.3.5 Programs to Assess and Manage Distribution System Real Loss The City implements a range of practices to identify, monitor, and reduce real water losses within its distribution system. City staff routinely conduct leak investigations and promptly repair leaks within Cityowned facilities. When leaks are identified on the customer side of the meter, the issue is reported to the customer and guidance is provided regarding appropriate repair actions.

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A significant portion of observed water loss within the service area is associated with irrigation systems.

To address this, the City performs off-season irrigation usage reviews to detect unscheduled flow. All irrigation meters are evaluated during the seasonal shutdown period, typically between December and March. Any flow detected during this period is investigated and corrected.

The City utilizes smart irrigation controllers across its irrigation accounts, which automatically adjust watering schedules based on evapotranspiration rates and precipitation. In addition, the irrigation system monitors flow conditions and can automatically close a master valve in response to unscheduled or excessive flow, thereby minimizing water loss.

As discussed in Section 9.3.2, the City is in the process of upgrading all water meters with cloud-based transmitters as part of its AMI program. These smart meters enable daily monitoring of water use and can alert water treatment plant staff to abnormal or continuous usage patterns, allowing for follow-up investigations. Residential customers who enroll in the free EyeOnWater platform may also set customized alerts to receive notifications of high or unusual water use via phone or email.

The City conducts annual water system audits to quantify water losses, commonly referred to as nonrevenue water, by comparing total system water production to metered consumption. The most recent Water Loss Audit is included in Appendix D and is summarized in Chapter 4 of this plan.

Implementation of this Demand Management Measure is ongoing and is expected to support the City’s water use efficiency objectives by enabling early detection of leaks and other losses, facilitating timely repairs, and minimizing overall system water losses.

9.3.6 Water Conservation Program Coordination and Staffing Support In line with the California Urban Water Conservation Council’s Memorandum of Understanding, the City has designated staff to actively develop, promote, enforce, and maintain water conservation programs.

The City has one code enforcement officer responsible for enforcing the City’s Municipal Code by responding to water complaints, monitoring water waste, issuing warnings and violations, and checking for excess landscape water use.

The effectiveness of this DMM is evaluated in conjunction with the success of the City’s water conservation efforts. As the City grows and water resources become more limited and expensive, the water conservation programs will continue to grow and promote the importance of water conservation.

Implementation of this DMM will continue to help the City achieve its water use targets by making implementation of the City’s water conservation program a top priority.

9.3.7 Other Demand Management Measures
In addition to the Demand Management Measures discussed above, the City implements several supplemental conservation programs that contribute to reduced water use, including residential conservation initiatives and large landscape irrigation efficiency programs.

9.3.7.1 Residential Conservation Programs
The City participates in the California Department of Water Resources’ Turf Replacement Rebate Program, which offers incentives of up to $2 per square foot, capped at $2,000 per property, for replacing turf grass

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with water-efficient landscaping. The program is funded through the Proposition 1 water bond. Turf replacement addresses a common source of residential outdoor water use, as spray irrigation systems serving turf landscapes are frequently associated with leaks and inefficiencies.

Over the past five years, no residential turf conversions have occurred within the City’s service area through this rebate program. This is likely attributable to the fact that City design standards for all new residential development require the use of subsurface irrigation systems, such as Eco-Mat®, which significantly reduce water losses associated with spray irrigation, including wind drift and overspray.

Implementation of this measure is ongoing and is expected to support City’s water use efficiency goals by reducing residential landscape irrigation demands. However, the effectiveness of this program is anticipated to diminish over time, as highly efficient subsurface irrigation systems are now standard for turf landscapes in new development, reducing the incentive for additional turf replacement.

9.3.7.2 Large Landscape Irrigation Conservation Program The City actively manages water use on City-owned landscaped areas by identifying and prioritizing high water-use sites for landscape renovation. In these areas, water-intensive plants are removed and replaced with drought-tolerant species that are comparable in size and visual character but require substantially less irrigation. Mulch is installed, and irrigation systems are modified or decommissioned where appropriate.

Landscape renovations are designed to reduce plant density while maximizing coverage by allowing shrubs to spread over a larger area, thereby decreasing overall water demand. Subsurface irrigation systems are incorporated as part of these improvements. Trees are maintained on minimal irrigation schedules necessary to preserve plant health, and any remaining turf areas are required to utilize EcoMat® subsurface drip irrigation. In addition, the City is transitioning its landscaped areas to weather-based irrigation controllers, which automatically adjust irrigation schedules based on evapotranspiration and precipitation data.

Implementation of this Demand Management Measure is ongoing and is expected to contribute to the City’s water use targets by reducing institutional landscape irrigation demands, replacing aging or leaking irrigation infrastructure, and demonstrating practical drought-tolerant landscaping approaches to the community.

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10 UWMP Adoption, Submittal, and Implementation
This chapter provides information regarding addressing the CWC requirements for public hearing, the UWMP adoption process, submitting an adopted UWMP and making the document available to the public, plan implementation, and the process for amending an adopted UWMP.

10.1 Inclusion of All 2025 Data
As indicated in Chapter 2, the City uses a calendar year for water supply and demand accounting, and therefore this 2025 UWMP includes data through December 2025.

10.2 Notice of Plan Preparation
Legal Requirements:

CWC Section 10621:
(b) Every urban water supplier required to prepare a plan shall…at least 60 days prior to the public hearing on the plan…notify any city or county within which the supplier provides waters supplies that the urban water supplier will be reviewing the plan and considering amendments or changes to the plan.

As described in Section 2.4.3 of this plan, the City provided notice of its intent to prepare the 2025 UWMP and WSCP to cities and counties within its service area, as well as to other relevant public agencies that rely on the same water supplies. These notices were distributed more than 60 days prior to adoption, in compliance with statutory requirements. Copies of the notices of preparation are included in Appendix C.

10.3 Notice of Public Hearing
Legal Requirements:

Water Code Section 10642:
…Prior to adopting either [the plan or water shortage contingency plan], 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 [see below]. 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.

Government Code Section 6066:

Publication of notice pursuant to this section shall be once a week for two successive weeks. Two publications in a newspaper published once a week or oftener, with at least five days intervening between the respective publication dates not counting such publication dates, are sufficient. The period of notice commences upon the first day of publication and terminates at the end of the fourteenth day, including therein the first day.

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The City issued a Notice of Public Hearing and established a public review period prior to adoption of the 2025 UWMP and WSCP. The notice was issued in accordance with California Government Code Section 6066 and was published in the Tracy Press for two successive weeks with seven days between publication dates. In addition, the notice was posted on the City website.

The Notice of Availability and Public Hearing included the date, time, and location of the public hearing, as well as information on where the draft plans could be reviewed by the public. A copy of the published notice is included in Appendix C.

Hard copies of the Draft 2025 UWMP were made available for public inspection at the City office, and an electronic version of the draft plan was also posted on the City website for public review.

The following interested parties and agencies also received notices of public hearing:
• Byron Bethany Irrigation District
• City of Tracy
• City of Manteca
• South San Joaquin Irrigation District
• San Joaquin County
• Association of California Water Agencies
• The Resmark Companies
• Kamilos Companies
• Trimark Communities, LLC
• California Department of Water Resources
Table 10-1 (DWR Table 10-1 Retail) provides confirmation that the notification was provided at least 60 days prior to the public hearing of the plan. Copies of notification letters are included in Appendix C.

Table 10-1 – Retail Notification to Cities and Counties (DWR Table 10-1 Retail) Submittal Table 10-1 Retail: Notification to Cities and Counties Water Code Section 10621(b) and 10642
City Name 60 Day Notice
Drop Down (yes/no)
Notice of Public Hearing
Drop Down (yes/no)
Add additional rows as needed
County Name
Drop Down List
60 Day Notice
Drop Down (yes/no)
Notice of Public Hearing
Drop Down (yes/no)
Add additional rows as needed
San Joaquin County Yes Yes
NOTES: No additional notes.

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10.4 Public Hearing and Adoption
Legal Requirements:

CWC 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…. 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.

Government Code Section 7291
…every local public agency… serving a substantial number of non-English-Speaking people, shall employ a sufficient number of qualified bilingual persons in public contact positions or as interpreters to assist those in such positions, to ensure provision of information and services in the language of the nonEnglish-speaking person.

The City has encouraged community involvement in the preparation of the 2025 UWMP and WSCP through public notices published in local newspapers and information posted on the City website. This section summarizes the public hearing process and formal adoption of the UWMP and WSCP.

10.4.1 Public Hearing
The public hearing provided the City water users and members of the general public with an opportunity to review the 2025 UWMP and ask questions regarding the City’s strategies for maintaining a reliable, safe, and high-quality water supply, as well as its approach to managing potential water shortage conditions. The public hearing was held on June 24, 2026, in conjunction with a regularly scheduled City Council meeting.

During the public hearing, the City also presented information regarding its compliance with the Water Conservation Act of 2009, including an overview of baseline water use, water use efficiency targets, current compliance status, the WSCP, and implementation of the UWMP.

10.4.2 Adoption
Following the public hearing, the City Council adopted the 2025 UWMP and the WSCP on June 24, 2026.

The WSCP was adopted through a separate resolution to allow for future updates independent of the UWMP, as needed. Copies of the adopted resolutions are provided in Appendix K.

10.5 Plan Submittal
Legal Requirements:

CWC Section 10621:
(e) Each urban water supplier shall update and submit its 2025 plan to the department by July 1, 2026… CWC Section 10635:
(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.

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CWC 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.

10.5.1 Submitting a UWMP and Water Shortage Contingency Plan to DWR A copy of this 2025 UWMP, including the WSCP, will be submitted electronically to DWR within 30 days of adoption.

10.5.2 Electronic Data Submittal
This 2025 UWMP, including the WSCP, and associated data will be submitted to DWR electronically using the WUEdata submittal tool.

10.5.3 Submitting a UWMP, including WSCP, to the California State Library The 2025 UWMP, including WSCP, will be submitted in electronic or hardcopy format to the California State Library within 30 days of adoption.

10.5.4 Submitting a UWMP to Cities and Counties
The 2025 UWMP will be submitted in electronic format to San Joaquin County and other agencies listed in Section 10.3 within 30 days of adoption.

10.6 Public Availability
Legal Requirements:

CWC 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.

Upon submittal to DWR, this 2025 UWMP will be available for public review at the City’s main office during normal business hours. An electronic copy of this UWMP will also be available for review and download on the City’s website(https://www.mountainhouseca.gov/).

10.7 Notification to Public Utilities Commission
Legal Requirements:

CWC Section 10621 (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.

The City is not regulated by the California Public Utilities Commission.

10.8 Plan Implementation
The 2025 UWMP will serve as the primary reference document for preparation of any SB 610 Water Supply Assessments or SB 221 Water Supply Verifications required for proposed projects between 2026 and 2030

ATTACHMENT C
Item 8.2
Mountain House                                               Page 293 of 741 City of Mountain House
2025 Urban Water Management Plan
May 2026
10-5
that are subject to the California Environmental Quality Act and would result in water demands equal to or greater than those associated with a 500-dwelling-unit development. In addition, the 2025 UWMP provides guidance for the development of new local water supplies and the continued implementation of water conservation programs and recycled water initiatives necessary to meet future regulatory and conservation requirements.

The Mountain House planned community is governed by three approved Specific Plans. Specific Plan I was approved prior to enactment of SB 610 and SB 221 and is therefore exempt from the requirement to prepare a Water Supply Assessment. Water Supply Assessments and Verifications of Water Supply were completed for Specific Plan II in 2006 and Specific Plan III in 2008. As a result, absent substantial revisions to any of the Specific Plans, additional Water Supply Assessments are not anticipated to be required through buildout of the Mountain House General Plan.

10.9 Amending an Adopted UWMP or Water Shortage Contingency Plan Legal Requirements:

CWC Section 10621:
(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).

CWC Section 10644:
(a)(1) 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.

10.9.1 Amending a UWMP
The plan may be updated at any time when the urban water supplier believes significant changes have occurred in population, land use, and/or water sources that may affect the contents of the plan. If major changes are made to the 2025 UWMP, the City will hold an additional public hearing and City Council will re-adopt the plan. Copies of amendments or changes to the plans will be submitted to DWR, the California State Library, and any city or county within which the supplier provides water supplies within 30 days after adoption.

10.9.2 Amending a Water Shortage Contingency Plan
Legal Requirements:

CWC Section 10644 (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…no later than 30 days after adoption, in accordance with protocols for submission and using electronic reporting tools developed by the department.

If the City revises the WSCP after DWR has approved the 2025 UWMP, copies of amendments or changes to the plans will be submitted electronically to the DWR through the WUEdata Portal within 30 days of its adoption.

Copies of the amended WSCP will also be sent to the California State Library and any city or county within which the supplier provides water supplies within 30 days after adoption.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 294 of 741 City of Mountain House
2025 Urban Water Management Plan
May 2026
11-1
11 References
[1] San Joaquin County Board of Supervisors. Mountain House Specific Plan I, II, and III, adopted November 10, 1994, amended through September 11, 2024.
[2] Mountain House Community Services District. 2020 Potable Water System Master Plan Update, prepared by West Yost Associates, December 2020.
[3] California Department of Finance. Population Estimates. https://dof.ca.gov. [4] California Department of Water Resources. California Irrigation Management Information System (CIMIS), Station 47 (Brentwood), Monthly Report. https://cimis.water.ca.gov. Accessed September 2025.
[5] U.S. Census Bureau. ACS Demographic and Housing Estimates, American Community Survey 5- Year Estimates Data Profiles, Table DP05.
https://data.census.gov/table/ACSDP5Y2024.DP05?q=Mountain+House+CDP,+California.

Accessed May 15, 2026.
[6] U.S. Census Bureau. Financial Characteristics, American Community Survey 5-Year Estimates Subject Tables, Table S2503.
https://data.census.gov/table/ACSST5Y2024.S2503?q=Mountain+House+CDP,+California.

Accessed May 15, 2026.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 295 of 741 City of Mountain House
2025 Urban Water Management Plan
May 2026
A
Appendix A
DWR UWMP Tables

ATTACHMENT C
Item 8.2
Mountain House                                               Page 296 of 741 CA3910027 City of Mountain House 7,837 5,207
Total 7,837 5,207
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 Table 2-3.

NOTES: Unit of measure for volumes are in AF.

Add additional rows as needed
Submittal Table 2-1 Retail: Public Water Systems
Public Water System
Number
Public Water System
Name
Number of Municipal
Connections 2025
Volume of Water
Supplied 2025

ATTACHMENT C
Item 8.2
Mountain House                                               Page 297 of 741 Select
One or
Both
Name of Regional Alliance or
RUWMP (Drop Down List)
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
drop-down.

NOTES: No additional notes.

Submittal Table 2-2: Plan Identification
Individual UWMP
Type of Plan

ATTACHMENT C
Item 8.2
Mountain House                                               Page 298 of 741 Supplier is a wholesale supplier
Supplier is a retail supplier
UWMP Tables are in calendar years
UWMP Tables are in fiscal years
Unit AF
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: No additional notes.

If using fiscal years provide month and date that the fiscal year begins (mm/dd)
Submittal Table 2-3: Supplier Identification
Type of Supplier (select one or both)
Fiscal or Calendar Year (select one)

ATTACHMENT C
Item 8.2
Mountain House                                               Page 299 of 741 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
Add additional rows as needed
Byron Bethany Irrigation District
NOTES: No additional notes.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 300 of 741 2025 2030 2035 2040 2045 2050(opt)
28,795 31,876 35,286 39,062 39,062
NOTES: 2025 population served is from DOF, Report E-4, Table 2 for 1/1/2025. Year 2040 population served is from the Mountain House 2020 Water Master Plan. Projected population values assume a uniform growth rate from 2025 to 2040 of 2.054 percent. Build out for the City is estimated to be in 2040, with minimal population increasing afterwards.

Therefore, the 2045 population is the same as the 2040 population. The projections for population served differ from the 2020 UWMP.

Submittal Table 3-1 Retail: Population - Current and Projected Water Code Section 10631(a)
Population
Served

ATTACHMENT C
Item 8.2
Mountain House                                               Page 301 of 741 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
Single Family Potable 2,873
Multi-Family Potable 507
Commercial Builder; Commercial; Utilities;
Construction; Manufacturing; Mining Potable 78
Institutional/Governmental Schools; City facilities Potable 357 Landscape City landscape irrigation Potable 917
Other Unbilled unmetered consumption Potable 12
Distribution System Water Loss Potable 464
5,207
0 5,207
Subtotal Potable
Subtotal Non-Potable
NOTES: Volume of Water Loss for 2025 was estimated based on water supplied and billed meter data as it has not been audited. The "Other" water use category accounts for unbilled unmetered water consumption and is estimated as 0.25% of the total billed consumption, in accordance with the AWWA water loss audit form.

Submittal Table 4-1 Retail: Total Uses for Potable and Non-Potable Water — Actual Water Code Section 10631(d)(1)
Additional Description
(as needed)
2025 Actual Water Use
Add additional rows as needed
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.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 302 of 741 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
2030 2035 2040 2045 2050 opt
Single Family Potable 3,180 3,520 3,897 3,897 -
Multi-Family Potable 561 621 688 688 -
Commercial
Builder; Commercial; Utilities;
Construction; Manufacturing;
Mining
Potable 86 95 105 105 -
Institutional/Governmental Schools; City facilities Potable 396 438 485 485 - Landscape City landscape irrigation Potable 1,015 1,123 1,243 1,243 - Other Unbilled Unmetered
Consumption
Potable 13 14 16 16
Distribution System Water Loss Potable 513 568 629 629 - 5,764 6,381 7,063 7,063 0
0 0 0 0 0
Total 5,764 6,381 7,063 7,063 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.

NOTES: Similar to projected population increases, the projected water use values are based on the same population percentage increase of 2.054 percent every year. The "Other" water use category accounts for unbilled unmetered water consumption and is estimated as 0.25% of the total billed consumption, in accordance with the AWWA water loss audit form.

Subtotal Potable
Subtotal Non-Potable
Submittal Table 4-2 Retail: Total Uses of Potable, and Non-Potable Water - Projected Water Code Section 10631(d)(1)
Additional Description
(as needed)
Projected Water Use
(Report To the Extent that Records are Available)
Add additional rows as needed.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 303 of 741 Are Future Water Savings Included in Projections?
Drop down list (y/n)
Yes
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.
4-7
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. 4-9 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: No additional notes.

DWR NOTES: Additional guidance is provided in Appendix K.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 304 of 741 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 No
Submittal Table 4-5 Retail: Water Loss Audit Reporting
Water Code Section 10631(d)(3)(A)
Report submittal status for all five years for each Public Water System as available.

Add rows as needed
CA3910027
DWR NOTES: Suppliers will provide a link to the WUEdata submittals of their Water Loss Audit Reports.

NOTES: Water Loss Audits provided in Appendix D.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 305 of 741 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)
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)
CA3910027 Yes 15.87
Gallons per
Service
Connection per
Day (GPSCD)
7,818 151.85 17.34 54.12
Gallons per
Service
Connection per
Day (GPSCD)
7,818 607.40 69.36
Submittal Table 4-6 Retail: Progress Towards 2028 Water Loss Standard Water Code Section 10631(d)(3)(C)
Public Water
System ID #
Reported in
Submittal Table
2-1 R
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 Apparent Water Loss
State Water Board Standard Most Recent AWWA Water Loss Audit Real Water
Loss Per Unit
per Day
State Water Board Standard Most Recent AWWA Water Loss Audit Apparent Water
Loss Per Unit per
Day
Add additional rows as needed.

Water Board's Calculated Water Loss Standards
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.

NOTES: The Fiscal Year 2024 Water Loss Audit, which is currently being prepared, was used to document the number of service connections, as well as real and apparent water losses.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 306 of 741 Actual 2025 GPCD
(From SB X7-7
Compliance Form)
Did Supplier meet
the 2020 Target in
2025?
No Individual 217 170 Yes NA
Submittal Table 5-1 Retail: SB X7-7 2020 Target Progress Water Code Section 10608.40
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.

Was Supplier part of a
merger or
consolidation since
2020?
Regional Alliance
Target or
Individual
Target?
Drop down list
2020 Target Actual 2020 GPCD
Did Supplier
Achieve Targeted
Reduction for
2020?
Only for suppliers that did not meet the
Target in 2020
See DWR NOTES below.

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
NOTES: 2020 Target GPCD value was met in 2020. 2025 GPCD is not needed to be analyzed.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 307 of 741 Groundwater Type
Drop Down List
May use each category
multiple times
Potable or
Non-Potable
(OPTIONAL)
Drop down list
Location or Basin Name 2021 2022 2023 2024 2025
0 0 0 0 0
Submittal Table 6-1 Retail: 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.

Check the box if all or part of the groundwater described below is desalinated. (OPTIONAL) Add additional rows as needed
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.

NOTES: City does not incorporate groundwater into their water usage.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 308 of 741 Name of Wastewater
Collection Agency
Wastewater
Volume Metered
or Estimated?

OPTIONAL
Drop Down List
Volume of Wastewater
Collected from UWMP
Service Area 2025
Name of Wastewater
Treatment Plant (WWTP) and
Place ID Number
Drop down list
Is WWTP Located
Within UWMP
Area?
Drop Down List
City of Mountain House Metered 1,843
Mountain House WWTP, Place
ID 241598
Yes
1,843
Recipient of Collected Wastewater
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.

NOTES: The City of Mountain House WWTP is currently operated under a third party contract with Inframark.

Add additional rows as needed
Total Wastewater Received from UWMP
Service Area in 2025:

Submittal Table 6-2 Retail: Wastewater Collected Within Service Area Water Code Section 10633(a)
Check the box if there is no wastewater collection system.

Proceed to the next table.

Percentage of 2025 service area served by wastewater collection system (OPTIONAL) Percentage of 2025 service area population served by wastewater collection system (OPTIONAL)
Wastewater Collection

ATTACHMENT C
Item 8.2
Mountain House                                               Page 309 of 741 Treatment Level
Drop down list
Volume Treatment Level
Drop down list
Volume Treatment Level
Drop down list
Volume Treatment Level
Drop down list
Volume Treatment Level
Drop down list
Volume Name of other
entity
Mountain House
WWTP, Place ID 241598 No 1,843 1,916 Tertiary 0 Tertiary 0 Tertiary 1,916 Tertiary 0 Tertiary 0 1,843 1,916 0 0 1,916 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 requrement in the Level of Treatment drop-down.

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

NOTES: Discrepancy between wastewater received and volume of water treated is due to the City’s WWTP receiving additional water to treat from outside the UWMP service area.

Required Discharge for
Instream Flow
(enter data as applicable)
Delivered to Another Entity for Additional
Treatment
(enter data as applicable)
Add additional rows as needed
Total
Submittal Table 6-3 Retail: Wastewater Treatment and Outcomes Within UWMP Service Area Water Code Section 10633(a)
Check the box if no wastewater is treated or disposed of within the UWMP service area.

Proceed to the next table.

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
2025 Volume of
Wastewater
Received from
UWMP Service
Area
(As Reported in
Submittal Table
6-2 R )
Total 2025
Volume of
Water
Treated
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)

ATTACHMENT C
Item 8.2
Mountain House                                               Page 310 of 741 Volume Narrative page number
(OPTIONAL)
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0
0 0 0 0 0 0 0
Supplemental Water Added in 2025 (volume) Include units (OPTIONAL) :

Source of 2025 Supplemental Water (OPTIONAL) :

Use Type
Drop down list
Potable or Non-Potable
(after treatment if treated)
(OPTIONAL)
Drop down list
Additional Information
(as needed)
Potential Recycled Water Use
2030 2050
NOTES: No additional notes.

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 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.

Add additional rows as needed
Total
Submittal Table 6-4 Retail: Recycled Water Direct Beneficial Uses Within Service Area Water Code Section 10633 (c)(e)
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.

Name(s) of Facility/ies Producing (Treating) the Recycled Water (OPTIONAL) :

Name of Supplier Operating the Recycled Water Distribution System (OPTIONAL) :
2025 2035 2040 2045

ATTACHMENT C
Item 8.2
Mountain House                                               Page 311 of 741 2020 Projection
for 2025
2025 Actual
Use
0 0
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.

Add additional rows as needed
NOTES: No additional 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.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 312 of 741 6-9
Name of Action Description Expected Increase in Recycled Water Use
Plan for Recycled Water Prepare a Recycled Water Feasibility Study and Master Plan 5,825
5,825
5,825
Add additional rows as needed
2026/2027
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
DWR NOTES:

Units of measure (AF, CCF, MG) 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.

The unit conversion to Acre Feet addresses the Water Code's requirement that this value be provided in acre-feet.

NOTES: No additional notes.

Planned Implementation Year
Total
Unit Conversion to AF

ATTACHMENT C
Item 8.2
Mountain House                                               Page 313 of 741 6-4
Drop Down
List
(yes/no)
If Yes, Supplier Name
Old River Riparian Rights No Potable 2040 All Year Types 2,570 Provide page location of narrative in the UWMP
Name of Future Projects
or Programs
Joint Project with other suppliers?
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)
Add additional rows 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 reported in Submittal Table 2-3.

NOTES: No additional notes.

Submittal Table 6-7 Retail: Expected Future Water Supply Projects or Programs Water Code Section 10631 (f)
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.

Procees to the next table.

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.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 314 of 741 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
Total Entitlement
(OPTIONAL)
See 'DWR Notes' below
Purchased or Imported Water BBID Drinking Water 5,207
5,207 0
0 0
5,207 0
Submittal Table 6-8 Retail: Water Supplies — Actual
Water Code Section 10631(b)
Additional Description
(as needed)
2025
Add additional rules as needed
Subtotal Potable
Subtotal Non-Potable
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.

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

NOTES: No additional notes.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 315 of 741 Water Supply
Reasonably
Available
Volume
Total Entitlement
(OPTIONAL)
See "DWR Notes"
below
Reasonably
Available
Volume
Total Entitlement
(OPTIONAL)
See "DWR Notes"
below
Reasonably
Available
Volume
Total Entitlement
(OPTIONAL)
See "DWR Notes"
below
Reasonably
Available
Volume
Total Entitlement
(OPTIONAL)
See "DWR Notes"
below
Reasonably
Available
Volume
Total Entitlement
(OPTIONAL)
See "DWR Notes"
below
Purchased or Imported Water BBID Potable 9,813 9,813 9,813 9,813 Surface Water Riparian
Rights Potable 2,570 2,570
9,813 0 9,813 0 12,383 0 12,383 0 0 0
0 0 0 0 0 0 0 0 0 0
9,813 0 9,813 0 12,383 0 12,383 0 0 0
Additional
Detail on
Water
Supply
Potable or Non-Potable
(after treatment if treated)
(OPTIONAL)
Drop Down list
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
2030 2035 2040 2045 2050 (opt)
Add additional rows as needed
Subtotal Potable
Subtotal Non-Potable
Total
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.

NOTES: No additional notes.

Submittal Table 6-9 Retail: Water Supplies — Projected
Water Code Section 10631 (b)

ATTACHMENT C
Item 8.2
Mountain House                                               Page 316 of 741 % of Average Supply
Average Year 2014 100%
Single-Dry Year 2015 17%
Consecutive Dry Years 1st Year 2012 100%
Consecutive Dry Years 2nd Year 2013 100%
Consecutive Dry Years 3rd Year 2014 100%
Consecutive Dry Years 4th Year 2015 17%
Consecutive Dry Years 5th Year 2016 100%
1,647
OPTIONAL Submittal Table 7-1 Retail: Basis of Water Year Data (Reliability Assessment) 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: Not Applicable
Quantification of available supplies is provided in this table as either volume only, percent only, or both.

Volume Available
9,813
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.

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

NOTES: In an average year, the volume available is assumed to equal the contractual amount available to the the City from BBID.

In 2015, which represents the single-dry year and the fourth year of a five-year drought, BBID delivered 17 percent of the contractual amount due to the 2015 curtailment order.
9,813
1,647
9,813
9,813
9,813

ATTACHMENT C
Item 8.2
Mountain House                                               Page 317 of 741 2030 2035 2040 2045 2050 (Opt)
Supply totals
(autofill from Submittal Table 6-
9 R)
9,813 9,813 12,383 12,383 0
Use totals
(autofill from Submittal Table 4-
2 R)
5,764 6,381 7,063 7,063 0
Surplus/(shortfall) 4,049 3,432 5,320 5,320 0
WSCP - supply augmentation
benefit
WSCP - use reduction savings
benefit
Revised Surplus/(shortfall)
Submittal Table 7-2 Retail: Normal Year Supply and Use Comparison Water Code Section 10635 (a)
OPTIONAL Planned WSCP Actions
DWR NOTES : Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3.

NOTES: Volumes are in AF. Beginning in 2040, the City can utilize its Old River riparian rights (2,570 AFY).

ATTACHMENT C
Item 8.2
Mountain House                                               Page 318 of 741 2030 2035 2040 2045 2050 (Opt)
Supply totals 1,647 1,647 4,217 4,217
Use totals 5,764 6,381 7,063 7,063 0
Surplus/(shortfall) (4,117) (4,734) (2,846) (2,846) 0
WSCP - supply
augmentation benefit
WSCP - use reduction
savings benefit
Revised Surplus/(shortfall)
OPTIONAL Planned WSCP Actions
DWR NOTES : Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3.

NOTES: Volumes are in AF. Beginning in 2040, the City can utilize its Old River riparian rights (2,570 AFY).

Submittal Table 7-3 Retail: Single Dry Year Supply and Use Comparison Water Code Section 10635(a)

ATTACHMENT C
Item 8.2
Mountain House                                               Page 319 of 741 2030 2035 2040 2045 2050 (Opt)
Supply totals 9,813 9,813 12,383 12,383
Use totals 5,764 6,381 7,063 7,063
Surplus/(shortfall) 4,049 3,432 5,320 5,320 0
WSCP - supply augmentation benefit
WSCP - use reduction savings benefit
Revised Surplus/(shortfall)
Supply totals 9,813 9,813 12,383 12,383
Use totals 5,764 6,381 7,063 7,063
Surplus/(shortfall) 4,049 3,432 5,320 5,320 0
WSCP - supply augmentation benefit
WSCP - use reduction savings benefit
Revised Surplus/(shortfall)
Supply totals 9,813 9,813 12,383 12,383
Use totals 5,764 6,381 7,063 7,063
Surplus/(shortfall) 4,049 3,432 5,320 5,320 0
WSCP - supply augmentation benefit
WSCP - use reduction savings benefit
Revised Surplus/(shortfall)
Supply totals 1,647 1,647 4,217 4,217
Use totals 5,764 6,381 7,063 7,063
Surplus/(shortfall) (4,117) (4,734) (2,846) (2,846) 0
WSCP - supply augmentation benefit
WSCP - use reduction savings benefit
Revised Surplus/(shortfall)
Supply totals 9,813 9,813 12,383 12,383
Use totals 5,764 6,381 7,063 7,063
Surplus/(shortfall) 4,049 3,432 5,320 5,320 0
WSCP - supply augmentation benefit
WSCP - use reduction savings benefit
Revised Surplus/(shortfall)
Third year OPTIONAL Planned WSCP Actions
First year
Second year OPTIONAL Planned WSCP Actions
Fifth year OPTIONAL Planned WSCP Actions
DWR NOTES: Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3.

Fourth year OPTIONAL Planned WSCP Actions
NOTES: Volumes are in AF. Beginning in 2040, the City can utilize its Old River riparian rights (2,570 AFY).

OPTIONAL Planned WSCP Actions
Submittal Table 7-4 Retail: Multiple Dry Years Supply and Use Comparison Water Code Section 10635(a)

ATTACHMENT C
Item 8.2
Mountain House                                               Page 320 of 741 2026 Total
Total Water Use 5,314
Total Supplies 9,813
Surplus/Shortfall w/o WSCP Action 4,499
WSCP - supply augmentation benefit
WSCP - use reduction savings benefit
Revised Surplus/(shortfall)
2027 Total
Total Water Use 5,423
Total Supplies 9,813
Surplus/Shortfall w/o WSCP Action 4,390
WSCP - supply augmentation benefit
WSCP - use reduction savings benefit
Revised Surplus/(shortfall)
2028 Total
Total Water Use 5,534
Total Supplies 9,813
Surplus/Shortfall w/o WSCP Action 4,279
WSCP - supply augmentation benefit
WSCP - use reduction savings benefit
Revised Surplus/(shortfall)
2029 Total
Total Water Use 5,648
Total Supplies 1,647
Surplus/Shortfall w/o WSCP Action (4,001)
WSCP - supply augmentation benefit
WSCP - use reduction savings benefit
Revised Surplus/(shortfall)
2030 Total
Total Water Use 5,764
Total Supplies 9,813
Surplus/Shortfall w/o WSCP Action 4,049
WSCP - supply augmentation benefit
WSCP - use reduction savings benefit
Revised Surplus/(shortfall)
Submittal Table 7-5 Retail: Five-Year Drought Risk Assessment Water Code Section 10635(b)(3)
OPTIONAL Planned WSCP Actions (use reduction and supply augmentation) OPTIONAL Planned WSCP Actions (use reduction and supply augmentation) OPTIONAL Planned WSCP Actions (use reduction and supply augmentation) OPTIONAL Planned WSCP Actions (use reduction and supply augmentation) OPTIONAL Planned WSCP Actions (use reduction and supply augmentation) DWR NOTES: Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3.

NOTES: No additional notes.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 321 of 741 Standard
Shortage
Levels
Percent Shortage
Range
Suppliers
Shortage
Levels
Percent
Shortage Range
1 Up to 10%
2 Up to 20%
3 Up to 30%
4 Up to 40%
5 Up to 50%
6 >50%
Submittal Table 8-1: Cross-reference for Standard vs
Supplier Shortage Levels
Water Code Section 10632(a)(3)(B)
Check the box if the Supplier uses the Standard
six levels of water shortage.

Proceed to the next table.

NOTES: No Additional Notes.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 322 of 741 Yes
Volume or
Percentage
Drop down
Shortage Gap
Reduction Value
(May be a range)
1 Other Actions (describe) Percentage 0 No action in stage 1. 2 Expand Public Information Campaign Percentage 1-10%
3 Transfers Percentage 1-10%
Purchase additional water supplies from
other agencies
4 Transfers Percentage 1-10%
Purchase additional water supplies from
other agencies
5 Transfers Percentage 1-10%
Purchase additional water supplies from
other agencies
6 Transfers Percentage 1-10%
Purchase additional water supplies from
other agencies
Is the Supplier completing this table using the standard six levels? (yes/no) Shortage
Level
Supply Augmentation Methods and
Other Actions by Water Supplier
Drop down list
These are the only categories that will be
accepted by the WUEdata online submittal tool
How much is this going to reduce the
shortage gap?
Additional Explanation or Reference
(OPTIONAL)
Add additional rows as needed
DWR NOTES: Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3.

NOTES: Shortage Level 2, Expand Public Information Campaign is going to reduce the shortgae gap by promoting the effectiveness of the demand reduction actions to be discussed in the following section. Shortage Level 3-6, Transfers, is going to reduce the shortage gap up the full shortage amount hence the Shortage Gap Reduction Value as a range. For example: If the City is mandating shortage level 3 actions and are only reducing the amount of water usage by 27%, this supplemental augmentation method will assist in reaching the specified reduction value.

Submittal Table 8-2 Retail: Supply Augmentation and Other Actions Water Code Section 10632(a)(4)(A),(C) and (E)

ATTACHMENT C
Item 8.2
Mountain House                                               Page 323 of 741 Yes
Volume or Percentage
Drop down
Shortage Gap
Reduction Value
(May be a range)
1 Landscape - Limit landscape irrigation
to specific times Volume 22 gpcd
Exterior irrigation at public, private, and commercial
locations shall be subject to time-of-day restrictions.

Irrigation in non-public areas is prohibited between
the hours of 11:00 a.m. and 6:00 p.m. during the
period from May 1 through October 1. Irrigation in
public areas is prohibited between the hours of 6:00
a.m. and 7:00 p.m.

No
1 Other - Customers must repair leaks,
breaks, and malfunctions in a timely
manner
Volume
Supports other
demand reduction
actions
To allow the escape of water through leaks, breaks or
malfunction within the customer's plumbing or
distribution system for any period of time within
which such break or leak should reasonably have
been discovered and corrected. It shall be presumed
that a period of twenty-four (24) hours after the
customer discovers such break, leak or malfunction,
or receives notice from the City, is a reasonable time
within which to correct such condition or to make
arrangements for correction. If the leak, break or
malfunction is discovered on a Sunday or legal
holiday, then it is presumed that the twenty-four (24)
hour period would begin at 12:00 midnight at the
end of the Sunday or legal holiday.

No
1 Other - Require automatic shut-off
hoses Volume
Supports other
demand reduction
actions
The use of water for washing vehicles or boats, and
cleaning buildings or mobile home exteriors, except
when using a shut-off nozzle on the hose.

No
1 Other - Prohibit vehicle washing except
at facilities using recycled or
recirculating water
Volume
Supports other
demand reduction
actions
The operation of any non-self-service commercial car
washes unless the soap/water for such use is
reclaimed.

No
1 CII - Restaurants may only serve water
upon request
Volume
Supports other
demand reduction
actions
Provide water to patrons in restaurants except when
specifically requested by the patrons. No
1 Water Features - Restrict water use for
decorative water features, such as
fountains
Volume
Supports other
demand reduction
actions
Use of water in publicly displayed ornamental
fountains in public or commercial establishments,
except when specifically approved by the City.

No
1 Other - Prohibit use of potable water
for washing hard surfaces Volume
Supports other
demand reduction
actions
Use of water to wash driveways, sidewalks, patios,
parking lots, aprons and other similar exterior
surfaces, except for sanitation, public health and
safety, and fire protection purposes.

No
1 Other Volume
Supports other
demand reduction
actions
The indiscriminate running of water or washing with
water not otherwise prohibited above which is
wasteful and without reasonable purpose and which
is evidenced by the runoff of water from the property
or into drainage facilities for more than ten (10)
minutes.

No
1 Other Volume
Supports other
demand reduction
actions
Obtain water from a fire hydrant, except for
construction purposes and other purposes
specifically authorized by the City Manager.

No
1 Other - Prohibit use of potable water
for construction and dust control Volume
Supports other
demand reduction
actions
Use of water for dust control purposes except for
recycled, reclaimed or other non-potable water,
except for health or safety purposes.

No
2 Landscape - Limit landscape irrigation
to specific times Volume
Supports other
demand reduction
actions
Irrigation of all exterior landscaping including, but
not limited to, turf areas, open ground, crops, trees,
grass, lawn, ground cover, shrubbery, or decorative
plantings using an irrigation system, hose, or
outdoor potable water faucet shall be allowed only
between the hours of 9:00 p.m. and 6:00 a.m.

Yes
2 Landscape - Limit landscape irrigation
to specific days Volume 22 gpcd
Irrigation of all exterior landscaping including, but
not limited to, turf areas, open ground, crops, trees,
grass, lawn, ground cover, shrubbery, or decorative
plantings using an irrigation system, hose, or
outdoor potable water faucet shall follow a 4-day
watering schedule and be allowed on: (1) Sundays,
Mondays, Wednesdays, and Fridays for properties
with an odd-numbered street address; and (2)
Sundays, Tuesdays, Thursdays, and Saturdays for
properties with an even-numbered street address.

Yes
2 Landscape - Restrict or prohibit runoff
from landscape irrigation Volume
Supports other
demand reduction
actions
Irrigation of exterior landscaping, turf areas, open
ground, crops, trees, grass, lawn, ground cover,
shrubbery, or decorative plantings in such a manner
or extent that allow water to run off or escape from
the premises or to be wasted.

Yes
3 Other Volume
Supports other
demand reduction
actions
All new requests for potable water for construction
shall be rejected by the City unless it is determined
that the request, with restrictions, will not prevent
the City from meeting it water conservation
objectives.

Yes
3 Water Features - Restrict water use for
decorative water features, such as
fountains
Volume
Supports other
demand reduction
actions
Potable water to ornamental fountains shall be
turned off. Yes
3 Landscape - Limit landscape irrigation
to specific days Volume 22 gpcd
Irrigation of all exterior landscaping including, but
not limited to, turf areas, open ground, crops, trees,
grass, lawn, ground cover, shrubbery, or decorative
plantings using an irrigation system, hose, or
outdoor potable water faucet shall follow a 3-day
watering schedule and be allowed on: (1) Sundays,
Wednesdays, and Fridays for properties with an oddnumbered street address; and (2) Tuesdays, Thursdays, and Saturdays for properties with an evennumbered street address.

Yes
4 Water Features - Restrict water use for
decorative water features, such as
fountains
Volume
Supports other
demand reduction
actions
All potable water for aesthetic water uses shall be
turned off. Yes
4 Other - Prohibit use of potable water
for construction and dust control Volume
Supports other
demand reduction
actions
All existing potable water use for construction
purposes shall cease. All new requests for potable
water for construction shall be rejected by the City.

Yes
4 Landscape - Limit landscape irrigation
to specific days Volume 22 gpcd
Irrigation of all exterior landscaping including, but
not limited to, turf areas, open ground, crops, trees,
grass, lawn, ground cover, shrubbery, or decorative
plantings using an irrigation system, hose, or
outdoor potable water faucet shall follow a 2-day
watering schedule and be allowed on: (1)
Wednesdays and Sundays for properties with an oddnumbered street address; and (2) Tuesdays and Saturdays for properties with an even-numbered
street address.

Yes
5 Landscape - Limit landscape irrigation
to specific days Volume 22 gpcd
Irrigation of all exterior landscaping including, but
not limited to, turf areas, open ground, crops, trees,
grass, lawn, ground cover, shrubbery, or decorative
plantings using an irrigation system, hose, or
outdoor potable water faucet shall follow a 1-day
watering schedule and be allowed on: (1) Sundays for
properties with an odd-numbered street address;
and (2) Saturdays for properties with an evennumbered street address.

Yes
6 Landscape - Limit landscape irrigation
to specific days Volume 22 gpcd All landscape irrigation shall be prohibited. Yes Supports other
demand reduction
actions
Any use of potable water from any fire hydrant is
prohibited, except by regularly constituted fire
protection agencies for fire suppression purposes or
by the City, when alternate water sources or recycled
water sources are available. The decision as to the
availability of alternate water sources shall be that of the City. In the absence of alternate water sources or
reclaimed water sources, use of potable water from a
hydrant may be used provided a permit for such use
is approved by the City.

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

NOTES: Shortage Gap Reduction Value for each level is estimated as 10% of the 2020 target of 217 gallons per capita per day.

Add additional rows as needed
Submittal Table 8-3 Retail: Demand Reduction Actions
Water Code Section 10632(a)(4)(B) and (E)
Is the Supplier completing this table using the standard six levels? (yes/no) Shortage
Level
Demand Reduction Actions
Drop down list
These are the only categories that will be
accepted by the WUEdata online submittal
tool. Select those that apply.

How much is this going to reduce the shortage
gap?
Additional Explanation or Reference
(OPTIONAL)
Penalty, Charge, or
Other
Enforcement?
For Retail Suppliers Only
Drop Down List
2 Other Volume

ATTACHMENT C
Item 8.2
Mountain House                                               Page 324 of 741 City Name 60 Day Notice
Drop Down (yes/no)
Notice of Public
Hearing
Drop Down (yes/no)
County Name
Drop Down List
60 Day Notice
Drop Down (yes/no)
Notice of Public
Hearing
Drop Down (yes/no)
San Joaquin County Yes Yes
Submittal Table 10-1 Retail: Notification to Cities and Counties Water Code Section 10621(b) and 10642
Add additional rows as needed
Add additional rows as needed
NOTES: No additional notes.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 325 of 741 City of Mountain House
2025 Urban Water Management Plan
May 2026
B
Appendix B
DWR UWMP Checklist

ATTACHMENT C
Item 8.2
Mountain House                                               Page 326 of 741 Retail
(x = required)
Wholesale
(x = required) Order 2025 Guidebook Location Water Code Section Summary as Applies to UWMP Subject Relevant Submittal Table 2025 UWMP Location x x 1 Chapter 1 10615 A plan shall describe and evaluate sources of supply, reasonable and practical efficient uses, reclamation  and demand management activities. Introduction and overview n/a Section 1.1 Page 1-1 x x 1 Chapter 1 10630.5
Each plan shall include a simple description of the Supplier’s plan including water availability, future requirements, a strategy for meeting needs, and other pertinent information. Additionally, a Supplier may also choose to include a simple description at the beginning of each chapter.

Plan preparation n/a Section 1.6 Page 1-4
x x 2.1 Section 2.1 10620(b) Every person that becomes a Supplier shall adopt UWMP within one year after it has become a Supplier. Plan preparation n/a Section 2.1.1 Page 2-1 x n/a 2.5 Section 2.5 10644 Supplier shall report the Public Water Systems number, volume of delivered water, and number of  connections that are included in this UWMP. Plan preparation 2-1 Section 2.1.1 Page 2-1 x x 2.5 Section 2.5 10644 Supplier shall report if this UWMP is an individual UWMP and whether the Supplier belongs to a regional  UWMP or regional alliance. Plan preparation 2-2 Section 2.2 Page 2-2x x 2.5 Section 2.5 10644 Supplier shall report whether the data is in fiscal or calendar years and the units of measure used for  reporting water volumes. Plan preparation 2-3 Section 2.3 Page 2-2x x 2.4 Section 2.4 10642 Provide supporting documentation that the Supplier has encouraged active involvement of diverse social, cultural, and economic elements of the population within the service area prior to and during the preparation of the plan and contingency plan.

Plan preparation n/a Section 2.4 Page 2-3
x x 2.4 Section 2.4.2 10620(d)(3)
Coordinate the preparation of its plan with other appropriate agencies in the area, including other Suppliers that share a common source, water management agencies, and relevant public agencies, to the extent practicable.

Plan preparation n/a Section 2.4 Page 2-3
x n/a 2.4 Section 2.4.1 10631(h) Retail Suppliers will include documentation that they have provided their Wholesale Supplier(s)—if  any—with water use projections from that source. Plan preparation 2-4 R Section 2.4.1 Page 2-4 n/a x 2.4 Section 2.4.1 10631(h)
Wholesale Suppliers will provide their Suppliers with identification and quantification of the existing and planned sources of water available from the Wholesale Supplier to the Supplier during various water year types.

Plan preparation 2-4 W N/A
x x 3 Chapter 3.0 10631(a) Describe the Supplier service area. System description n/a Section 3.2 Page 3-1x x 3.3 Section 3.3 10631(a) Describe the climate of the Supplier’s service area. System description n/a Section 3.3 Page 3-4 x x 3.4 Section 3.4.1 10631(a) Provide the current and projected service area populations for 2030, 2035, 2040, 2045 and optionally  2050. System description 3-1 Section 3.4.1 Page 3-5 x x 3.4 Section 3.4.2 10631(a) Describe other social, economic, and demographic factors affecting the Supplier’s water management  planning. System description n/a Section 3.4.2 Page 3-5 x x 3.5 Section 3.5 10631(a)
Describe the land uses within the service area… include the current and projected land uses within the existing or anticipated service area affecting the Supplier’s water management planning. Describe the land uses within the service area.

System description and baselines n/a Section 3.5 Page 3-6 x Optional 4.2 Sections 4.2.3 and 4.2.4 10631(d)(1) Quantify past, current, and projected water use, identifying the uses among water use sectors. System water use 4-1 and 4-2 Section 4.2 Page 4-1x Optional 4.3 Section 4.3.1 10631(d)(3)(A) Report the distribution system water loss for each of the five years preceding the plan update. System water use 4-5 Section 4.3 Page 4-10 x n/a 4.3 Section 4.3.2 10631(d)(3)(C) Retail Suppliers shall provide data to show the distribution loss standards were met. System water use 4-6 Section 4.4 Page 4-11x n/a 4.2 Section 4.2.5.4 10631.1(a) Include projected water use needed for lower income housing projected in the service area of the  Supplier. System water use 4-3 Section 4.2.6 Page 4-8 x n/a 4.2 Section 4.2.5.3 10631(d)(4)(A) In projected water use, include estimates of water savings from adopted codes, plans, and other policies  or laws. System water use 4-3 Section 4.2.6 Page 4-8x n/a 4.2 Section 4.2.5.3 10631(d)(4)(B) Provide citations of codes, standards, ordinances, or plans used to make water use projections. System water use 4-3 Section 4.2.6 Page 4-8x n/a 4.2 Section 4.2.5.3 10631(d)(4)(B)(ii) To the extent that a Supplier reports the information described in subparagraph (A), an urban water Supplier shall… 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.

System water use 4-3 Section 4.2.6 Page 4-8
x x 4.2 Section 4.2.5.6 10635(b) Demands under climate change considerations must be included as part of the drought risk assessment. System water use n/a Section 4.2.7 Page 4-9 n/a x 5.1 Section 5.1 10608.36 Wholesale Suppliers shall include an assessment of present and proposed future measures, programs,  and policies to help their Retail Suppliers achieve targeted water use reductions. Baselines and targets n/a N/A x n/a 5.2 Section 5.2 10608.4
Retail Suppliers shall report on their compliance in meeting their water use targets. Reporting requirements will vary depending on whether the Supplier:- Was considered an urban retail water supplier in 2020,- Met its 2020 target in 2020, or- Was part of a merger or consolidation since 2020.Chapter 5 Subsections 5.2.1, 5.2.2, and 5.2.3 address each of these situations.

Baselines and targets 5-1 Section 5.1 Page 5-1
x x 6.1 Section 6.1 10631(b)(2) When multiple sources of water supply are identified, describe the management of each supply in  relationship to other identified supplies. System supplies n/a Section 6.1 Page 6-1 x x 6.1 Sections 6.1 and 6.2 10631(b)(1)
Provide a discussion of anticipated supply availability under a normal, single dry year, and a drought lasting five years, as well as more frequent and severe periods of drought, including changes in supply due to climate change.

System supplies n/a Section 6.1.11 Page 6-18
x x 6.2 Section 6.2.2 10631(b)(4)(C)
Indicate whether groundwater is an existing or planned source of water available to the Supplier. If groundwater is identified as an existing or planned source of water… (include) a detailed description and analysis of the location, amount and sufficiency of groundwater pumped by the Supplier for the past five years.

Water supplies and recycled water 6-1 Section 6.1.2 Page 6-2 x x 6.2 Section 6.2.2 10631(b)(4)(A)
Indicate whether a groundwater sustainability plan or groundwater management plan has been adopted by the Supplier or if there is any other specific authorization for groundwater management. Include a copy of the plan or authorization.

System supplies n/a Section 6.1.2 Page 6-2
x x 6.2 Section 6.2.2 10631(b)(4)(B) Describe the groundwater basin. System supplies n/a n/a x x 6.2 Section 6.2.2 10631(b)(4)(B) Indicate if the basin has been adjudicated and include a copy of the court order or decree and a  description of the amount of water the Supplier has the legal right to pump. System supplies n/a n/a x x 6.2 Section 6.2.2 10631(b)(4)(B) For unadjudicated basins… (include) information as to whether DWR has identified the basin as a high-  or medium-priority basin in the most current official departmental bulletin… Water supplies and recycled  water n/a n/a x x 6.2 Section 6.2.2 10631(b)(4)(B) For unadjudicated basins… describe efforts by the Supplier to coordinate with sustainability or  groundwater agencies to achieve sustainable groundwater conditions. Water supplies and recycled  water n/a n/a

ATTACHMENT
C
Item 8.2
Mountain House                                               Page 327 of 741 x x 6.2 Section 6.2.2. 10631(b)(4)(C)
If groundwater is identified as an existing or planned source of water… (include) a detailed description and analysis of the location, amount and sufficiency of groundwater pumped by the Supplier for the past five years.

System supplies n/a n/a
x x 6.2 Section 6.2.2 10631(b)(4)(D) Provide a detailed description and analysis of the amount and location of groundwater that is projected  to be pumped. System supplies 6-9 n/a x x 6.1 Section 6.1 10631(b) Identify and quantify the existing and planned sources of water available for 2025, 2030, 2035, 2040,  2045 and optionally 2050. System supplies 6-8 and 6-9 Section 6.1.10.2 Page 6-15 x x 6.2 Section 6.2.7 10631(c) Describe the opportunities for exchanges or transfers of water on a short-term or long-term basis. System supplies n/a Section 6.1.7 Page 6-13x n/a 6.2 Section 6.2.5 10633(a) Describe the wastewater collection and treatment systems in the Supplier’s service area with quantified  amount of collection and treatment and the disposal methods. System supplies (recycled water) 6-2 Section 6.1.5.2 Page 6-6 x x 6.2 Section 6.2.5 10633(b) Describe the quantity of treated wastewater that meets recycled water standards, is being discharged,  and is otherwise available for use in a recycled water project. System supplies (recycled water) 6-3 Section 6.1.5.2 Page 6-6x x 6.2 Section 6.2.5 10633(c) Describe the recycled water currently being used in the Supplier's service area. System supplies (recycled water) 6-4 Section 6.1.5.3 Page 6-9 x x 6.2 Section 6.2.5 10633(d) Describe and quantify the potential uses of recycled water and provide a determination of the technical  and economic feasibility of those uses. System supplies (recycled water) 6-4 Section 6.1.5.4 Page 6-9 x x 6.2 Section 6.2.5 10633(e) Describe the projected use of recycled water within the Supplier's service area at the end of 5, 10, 15,  and 20 years, and describe the actual use of recycled water in comparison to uses previously projected. System supplies (recycled water) 6-4 and 6-5 Section 6.1.5.4 Page 6-9 x x 6.2 Section 6.2.5 10633(f) Describe the actions that 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. System supplies (recycled water) 6-6 Section 6.1.5.5 Page 6-11 x x 6.2 Section 6.2.5 10633(g) Provide a plan for optimizing the use of recycled water in the Supplier's service area. System supplies (recycled water) n/a Section 6.1.5.5 Page 6-11 x x 6.2 Section 6.2.6 10631(g) Describe desalinated water project opportunities for long-term supply. System supplies 6-7 Section 6.1.6 Page 6-12 x x 6.2 Section 6.2.10 10631(f)
Describe the expected future water supply projects and programs that may be undertaken by the water Supplier to address water supply reliability in average, single-dry, and for a period of drought lasting five consecutive water years.

System supplies 6-7 Section 6.1.9 Page 6-13
x x 6.3 Section 6.3 and Appendix O 10631.2(a) The UWMP must include energy information, as stated in the code, that a Supplier can readily obtain. System suppliers, energy  intensity O-1A, O-1B, O-1C, and O-2 Section 6.2 Page 6-18 x 7.1 Section 7.1 10634 Provide information on the quality of existing sources of water available to the Supplier and the manner  in which water quality affects water management strategies and supply reliability. Water supply reliability  assessment n/a Section 7.1.3 Page 7-2 x x 7.2 Section 7.2 10635(a)
Service Reliability Assessment: Assess the water supply reliability during normal, dry, and a drought lasting five consecutive water years by comparing the total water supply sources available to the Supplier with the total projected water use over the next 20 years.

Water supply reliability assessment 7-2, 7-3, and 7-4 Section 7.2 Page 7-3 x x 7.2 Section 7.2.3 10620(f) Describe water management tools and options to maximize resources and minimize the need to import  water from other regions. Water supply reliability  assessment n/a Section 7.2.3 Page 7-7 x x 7.3 Section 7.3 10635(b) Provide a drought risk assessment as part of information considered in developing the demand  management measures and water supply projects. Water supply reliability  assessment n/a Section 7.3 Page 7-8x x 7.3 Section 7.3 10635(b)(1) Include 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 years.

Water supply reliability assessment n/a Section 7.3.1 Page 7-9 x x 7.3 Section 7.3 10635(b)(2) Include a determination of the reliability of each source of supply under a variety of water shortage  conditions. Water supply reliability  assessment n/a Section 7.3.2 Page 7-9 x x 7.3 Section 7.3 10635(b)(3) Include a comparison of the total water supply sources available to the Supplier with the total projected  water use for the drought period. Water supply reliability  assessment 7-5 Section 7.3.3 Page 7-9x x 7.3 Section 7.3 10635(b)(4) Include 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.

Water supply reliability assessment n/a Section 7.3.3 Page 7-9 x x 8 Chapter 8 10632(a) Provide a water shortage contingency plan (WSCP) with specified elements below. Water shortage contingency  planning n/a Appendix H x x 8 Chapter 8 10632(a)(1) Provide an analysis of water supply reliability (from Guidebook Chapter 7) in the WSCP. Water shortage contingency  planning n/a Appendix H Section 2 Page 3x x 8.2 Section 8.2 10632(a)(2)(A) Provide the written decision-making process and other methods that the Supplier will use each year to  determine its water reliability. Water shortage contingency  planning n/a Appendix H Section 3.1 Page 6x x 8.2 Section 8.2 10632(a)(2)(B) Provide data and methodology to evaluate the Supplier’s water reliability for the current year and one  dry year pursuant to factors in the code. Water shortage contingency  planning n/a Appendix H Section 3.2 Page 6x x 8.3 Section 8.3 10632(a)(3)(A) Define six standard water shortage levels of 10%, 20%, 30%, 40%, 50% shortage, and greater than 50% shortage. These levels shall be based on supply conditions, including percent reductions in supply, changes in groundwater levels, changes in surface elevation, or other conditions. The shortage levels shall also apply to a catastrophic interruption of supply.

Water shortage contingency planning n/a Appendix H Section 4 Page 8 x x 8.3 Section 8.3 10632(a)(3)(B) Suppliers with an existing WSCP that uses different water shortage levels must cross reference their  categories with the six standard categories. Water shortage contingency  planning 8-1 Appendix H Section 4 Page 8 x x 8.4 Section 8.4 10632(a)(4)(A) Suppliers with WSCPs that align with the defined shortage levels must specify locally appropriate supply  augmentation actions. Water shortage contingency  planning 8-2 Appendix H Section 5.1 Page 11x x 8.4 Section 8.4 10632(a)(4)(B) Specify locally appropriate demand reduction actions to adequately respond to shortages. Water shortage contingency  planning 8-3 Appendix H Section 5.2 Page 12x x 8.4 Section 8.4 10632(a)(4)(C) Specify locally appropriate operational changes. Water shortage contingency  planning 8-2 Appendix H Section 5.3 Page 20x x 8.4 Section 8.4 10632(a)(4)(D) Specify additional mandatory prohibitions against specific water use practices that are in addition to  State-mandated prohibitions are appropriate to local conditions. Water shortage contingency  planning Table 8-3 Appendix H Section 5.4 Page 21 x x 8.4 Section 8.4 10632(a)(4)(E) Estimate the extent to which the gap between supplies and demand will be reduced by implementation  of the action. Water shortage contingency  planning 8-2 and 8-3 Appendix H Section 5.2 Page 12x x 8.4 Section 8.4.6 10632.5 The UWMP shall include a seismic risk assessment and mitigation plan. Water shortage contingency plan n/a Appendix H Section 5.6 Page 21 x x 8.5 Section 8.5 10632(a)(5)(A) Suppliers must describe that they will inform customers, the public and others regarding any current or  predicted water shortages. Water shortage contingency  planning n/a Appendix H Section 6 Page 24 x x 8.5 Section 8.5 10632(a)(5)(B),  10632(a)(5)(C) Suppliers must describe that they will inform customers, the public and others regarding any shortage  response actions triggered or anticipated to be triggered and other relevant communications. Water shortage contingency  planning n/a Appendix H Section 6 Page 24 x n/a 8.6 Section 8.6 10632(a)(6) Retail Supplier must describe how it will ensure compliance with and enforce provisions of the WSCP. Water shortage contingency  planning n/a Appendix H Section 7 Page 26

ATTACHMENT
C
Item 8.2
Mountain House                                               Page 328 of 741 x x 8.7 Section 8.7 10632(a)(7)(A) Describe the legal authority that empowers the Supplier to enforce shortage response actions. Water shortage contingency  planning n/a Appendix H Section 8 Page 27 x x 8.7 Section 8.7 10632(a)(7)(B) Provide a statement that the Supplier will declare a water shortage emergency per Water Code  Chapter 3. Water Shortage Emergencies. Water shortage contingency  planning n/a Appendix H Section 8 Page 27x x 8.7 Section 8.7 10632(a)(7)(C) Provide a statement that the Supplier will coordinate with any city or county within which it provides  water for the possible proclamation of a local emergency. Water shortage contingency  planning n/a Appendix H Section 8 Page 27x x 8.8 Section 8.8 10632(a)(8)(A) Describe the potential revenue reductions and expense increases associated with activated shortage  response actions. Water shortage contingency  planning n/a Appendix H Section 9 Page 29x x 8.8 Section 8.8 10632(a)(8)(B) Provide a description of mitigation actions needed to address revenue reductions and expense increases  associated with activated shortage response actions. Water shortage contingency  planning n/a Appendix H Section 9 Page 29x n/a 8.8 Section 8.8 10632(a)(8)(C) Retail Suppliers must describe the cost of compliance with Water Code Chapter 3.3, Excessive Residential Water Use During Drought. Water shortage contingency  planning n/a Appendix H Section 9 Page 29x n/a 8.9 Section 8.9 10632(a)(9) Retail Suppliers must describe the monitoring and reporting requirements and procedures that ensure  appropriate data are collected, tracked, and analyzed for purposes of monitoring customer compliance. Water shortage contingency  planning n/a Appendix H Section 10 Page 31 x x 8.10 Section 8.10 10632(a)(10) Describe reevaluation and improvement procedures for monitoring and evaluation the WSCP to ensure  risk tolerance is adequate and appropriate water shortage mitigation strategies are implemented. Water shortage contingency  planning n/a Appendix H Section 11 Page 32 x n/a 8.11 Section 8.11 10632(b) Analyze and define water features that are artificially supplied with water, including ponds, lakes,  waterfalls, and fountains, separately from swimming pools and spas. Water shortage contingency  planning n/a Appendix H Section 12 Page 33 x x 8.12 Section 8.12 10632(c) Make available the WSCP to customers and any city or county where it provides water within 30 days  after adoption of the plan. Water shortage contingency  planning n/a Appendix H Section 13 Page 34x n/a 9.1 Sections 9.1 10631(e)(1) Retail Suppliers shall provide a description of the nature and extent of each demand management measure implemented over the past five years. The description will address specific measures listed in code.

Demand management measures n/a Section 9.2.1 Page 9-1
n/a x 9.2 Sections 9.2 10631(e)(2) Wholesale Suppliers shall describe specific demand management measures listed in code, their  distribution system asset management program, and Supplier assistance program. Demand management measures n/a N/A x n/a 10 Chapter 10 10608.26(a) Retail Suppliers shall conduct a public hearing to discuss adoption, implementation, and economic  impact of water use targets (recommended to discuss compliance). Plan adoption, submittal, and  implementation n/a Section 10.4 Page 10-3 x x 10.2 Section 10.2.1 10621(b)
Notify, at least 60 days prior to the public hearing, any city or county within which the Supplier provides water that the Supplier will be reviewing the UWMP and considering amendments or changes to the plan.

Plan adoption, submittal, and implementation 10-1 Section 10.3 Page 10-1 x x 10.4 Section 10.4 10621(f) Each urban water Supplier shall update and submit its 2025 plan  to DWR by July 1, 202 6. Plan adoption, submittal, and  implementation n/a Section 10.5.1 Page 10-4 x x 10.2 Sections 10.2.2, 10.3, and 10.5 10642 Provide supporting documentation that the Supplier made the UWMP and WSCP available for public  inspection, published notice of the public hearing, and held a public hearing about the UWMP and WSCP. Plan adoption, submittal, and  implementation n/a Section 10 Page 10-1 x x 10.2 Section 10.2.2 10642 The Supplier is to provide the time and place of the hearing to any city or county within which the  Supplier provides water. Plan adoption, submittal, and  implementation 10-1 Section 10.3 Page 10-1 x x 10.3 Section 10.3.2 10642 Provide supporting documentation that the UWMP and WSCP has been adopted as prepared or modified. Plan adoption, submittal, and  implementation n/a Section 10.4.2 Page 10-3x x 10.4 Section 10.4 10644(a) Provide supporting documentation that the Supplier has submitted their UWMP to the California State  Library. Plan adoption, submittal, and  implementation n/a Section 10.5.3 Page 10-4x x 10.4 Section 10.4 10644(a)(1) Provide supporting documentation that the Supplier has submitted their UWMP to any city or county  within which the Supplier provides water no later than 30 days after adoption. Plan adoption, submittal, and  implementation n/a Section 10.5.4 Page 10-4x x 10.4 Sections 10.4.1 and 10.4.2 10644(a)(2) The UWMP, or amendments to the UWMP, submitted to DWR shall be submitted electronically. Plan adoption, submittal, and  implementation n/a Section 10.9.1 Page 10-5x x 10.7 Section 10.7.2 10644(b) If revised, submit a copy of the WSCP to DWR within 30 days of adoption. Plan adoption, submittal, and  implementation n/a Section 10.9.1 Page 10-5x x 10.5 Section 10.5 10645(a) Provide supporting documentation that, not later than 30 days after filing a copy of its UWMP with DWR,  the Supplier has or will make the plan available for public review during normal business hours. Plan adoption, submittal, and  implementation n/a Section 10.6 Page 10-4 x x 10.5 Section 10.5 10645(b) Provide supporting documentation that, not later than 30 days after filing a copy of its WSCP with DWR,  the Supplier has or will make the plan available for public review during normal business hours. Plan adoption, submittal, and  implementation n/a Section 10.6 Page 10-4 x x 10.6 Section 10.6 10621(c) If Supplier is regulated by the Public Utilities Commission, include its plan and contingency plan as part  of its general rate case filings. Plan adoption, submittal, and  implementation n/a Section 10.7 Page 10-4

ATTACHMENT
C
Item 8.2
Mountain House                                               Page 329 of 741 City of Mountain House
2025 Urban Water Management Plan
May 2026
C
Appendix C
Agency and Public Notices

ATTACHMENT C
Item 8.2
Mountain House                                               Page 330 of 741 April 13, 2026
SUBJECT: Notice of Preparation for the 2025 City of Mountain House Urban Water Management Plan (UWMP) and Water Shortage Contingency Plan (WSCP)
To Whom It May Concern,
The Urban Water Management Planning Act, California Water Code (CWC) § 10610 et seq., requires every urban water supplier 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 to prepare and adopt an Urban Water Management Plan (UWMP) and update that plan every five years. The UWMP is a planning document to support long-term resource planning and ensure adequate water supplies are available to meet existing and future water demands.

Pursuant to the requirements of the CWC, Division 6, Part 2.6 Urban Water Management Planning, Section 10621 (b), every urban water supplier required to prepare an UWMP 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.

Per CWC Section 10642, prior to adopting such plan(s), the urban water supplier shall make the UWMP and Water Shortage Contingency Plan (WSCP) available for public inspection within the jurisdiction of the water supplier. In addition, 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.

This letter is intended to notify your agency that the City of Mountain House (City) is currently in the process of preparing the 2025 UWMP and WSCP. The City’s public hearing for the 2025 UWMP and WSCP is scheduled for June 24, 2026. Comments can be submitted prior or during the public hearing.

For further information on the public hearing or the UWMP and WSCP update, refer to the City’s website, https://www.mountainhouseca.gov/, or please contact us at (209) 831-2300.

Sincerely,
Karen Morgan
Utility Manager

ATTACHMENT C
Item 8.2
Mountain House                                               Page 331 of 741 City of Mountain House
2025 Urban Water Management Plan
May 2026
D
Appendix D
Water Loss Audits
(2020-2023)

ATTACHMENT C
Item 8.2
Mountain House                                               Page 332 of 741

ATTACHMENT C
Item 8.2
Mountain House                                               Page 333 of 741 Water Audit Report for:

Reporting Year:

All volumes to be entered as: MILLION GALLONS (US) PER YEAR Master Meter and Supply Error Adjustments
WATER SUPPLIED Pcnt: Value:

Volume from own sources: 6 1,559.119 MG/Yr 9 0.00% MG/Yr Water imported: n/a 0.000 MG/Yr 9 0.00% MG/Yr
Water exported: n/a 0.000 MG/Yr MG/Yr
Enter negative % or value for under-registration
WATER SUPPLIED: 1,559.119 MG/Yr Enter positive % or value for over-registration .

AUTHORIZED CONSUMPTION
Billed metered: 8 1,409.360 MG/Yr
Billed unmetered: 2 15.402 MG/Yr
Unbilled metered: n/a 0.000 MG/Yr Pcnt: Value:

Unbilled unmetered: 5 3.898 MG/Yr 1.25% 24061 MG/Yr
AUTHORIZED CONSUMPTION: 1,428.660 MG/Yr
WATER LOSSES (Water Supplied - Authorized Consumption) 130.459 MG/Yr Apparent Losses Pcnt: Value:

Unauthorized consumption: 1 3.898 MG/Yr 0.25% MG/Yr
Customer metering inaccuracies: 2 14.236 MG/Yr 1.00% MG/Yr Systematic data handling errors: 5 3.523 MG/Yr 0.25% MG/Yr Apparent Losses: 21.657 MG/Yr
Real Losses (Current Annual Real Losses or CARL)
Real Losses = Water Losses - Apparent Losses: 108.802 MG/Yr WATER LOSSES: 130.459 MG/Yr

NON-REVENUE WATER
NON-REVENUE WATER: 134.357 MG/Yr
= Water Losses + Unbilled Metered + Unbilled Unmetered

SYSTEM DATA
Length of mains: 10 101.8 miles
Number of active AND inactive service connections: 10 7,272 Service connection density: 71 conn./mile main
Yes
Average length of customer service line: ft
Average operating pressure: 10 65.0 psi

COST DATA
Total annual cost of operating water system: 10 $2,994,904 $/Year Customer retail unit cost (applied to Apparent Losses): 10 $0.90 Variable production cost (applied to Real Losses): 10 $919.82 $/Million gallons WATER AUDIT DATA VALIDITY SCORE:

PRIORITY AREAS FOR ATTENTION:
1: Volume from own sources
2: Billed unmetered
3: Customer metering inaccuracies
AWWA Free Water Audit Software:

Reporting Worksheet

3.898
2021 7/2021 - 6/2022
Mountain House (CA3910027)
<----------- Enter grading in column 'E' and 'J' ----------> 148.116
Based on the information provided, audit accuracy can be improved by addressing the following components:
$/100 cubic feet (ccf)
Default option selected for unauthorized consumption - a grading of 5 is applied but not displayed

3.523
*** YOUR SCORE IS: 66 out of 100 ***
A weighted scale for the components of consumption and water loss is included in the calculation of the Water Audit Data Validity Score Default option selected for Systematic data handling errors - a grading of 5 is applied but not displayed Average length of customer service line has been set to zero and a data grading score of 10 has been applied Are customer meters typically located at the curbstop or property line? ?
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Please enter data in the white cells below. Where available, metered values should be used; if metered values are unavailable please estimate a value. Indicate your confidence in the accuracy of the input data by grading each component (n/a or 1-10) using the drop-down list to the left of the input cell. Hover the mouse over the cell to obtain a description of the grades ?
?
?
?
?
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(length of service line, beyond the property
boundary, that is the responsibility of the utility)
Use buttons to select
percentage of water supplied
OR
value
Click here: ?
for help using option
buttons below
?
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?
?
+
+ Click to add a comment
WAS v5.0
+
+
+
+
+
+
American Water Works Association.
?
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?
+
+
+
+
+
+
+
+
+
+
+
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+
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To select the correct data grading for each input, determine the highest grade where the utility meets or exceeds all criteria for that grade and all grades below it.

Use Customer Retail Unit Cost to value real losses
AWWA Free Water Audit Software v5.0 Reporting Worksheet 2

ATTACHMENT C
Item 8.2
Mountain House                                               Page 334 of 741 Water Audit Report for:

Audit Year:

All volumes to be entered as: MILLION GALLONS (US) PER YEAR WATER SUPPLIED choose entry option:

VOS Volume from Own Sources: n g 7 1,388.680 MG/Yr n g percent MG/Yr under-registration VOSEA WI Water Imported: n g 0.000 MG/Yr n g 0.00% percent MG/Yr select….. WIEA WE Water Exported: n g 0.000 MG/Yr n g percent MG/Yr select….. WEEA 1,388.680 MG/Yr
.

AUTHORIZED CONSUMPTION
BMAC Billed Metered: n g 8 1,215.736 MG/Yr
BUAC Billed Unmetered: n g 2 12.000 MG/Yr
UMAC Unbilled Metered: n g n/a 0.000 MG/Yr choose entry option:

UUAC Unbilled Unmetered: n g 3 3.069 MG/Yr 0.25% default MG/Yr 24061 Default option selected for Unbilled Unmetered, with automatic data grading of 3 1,230.805 MG/Yr
WATER LOSSES 157.875 MG/Yr
Apparent Losses
Default option selected for Systematic Data Handling Errors, with automatic data grading of 3 choose entry option:

SDHE Systematic Data Handling Errors: n g 3 3.069 MG/Yr 0.25% default MG/Yr CMI Customer Metering Inaccuracies: n g 2 12.280 MG/Yr 1.00% percent MG/Yr under-registration UC Unauthorized Consumption: n g 3 3.069 MG/Yr 0.25% default MG/Yr Default option selected for Unauthorized Consumption, with automatic data grading of 3

18.419 MG/Yr
Real Losses
139.456 MG/Yr
157.875 MG/Yr

NON-REVENUE WATER
160.944 MG/Yr

SYSTEM DATA
Lm Length of mains: n g 6 102.7 miles (including fire hydrant lead lengths) Nc Number of service connections: n g 6 7,398 (active and inactive) Service connection density: 72 conn./mile main
Yes
Lp Average length of (private) customer service line: n g 10 ft (average distance between property line and meter) AOP Average Operating Pressure: n g 10 65.0 psi

COST DATA
CRUC Customer Retail Unit Charge: n g 9 $0.90
VPC Variable Production Cost: n g 9 $695.78 $/Million gallons $/yr (optional input) WATER AUDIT DATA VALIDITY TIER:
go to
dashboard
PRIORITY AREAS FOR ATTENTION TO IMPROVE DATA VALIDITY: KEY PERFORMANCE INDICATOR TARGETS:

Based on the information provided, audit reliability can be most improved by addressing the following components: OPTIONAL: If targets exist for the operational performance indicators, they can be input below:
1: Volume from Own Sources (VOS) Unit Total Losses: 21.4 gal/conn/day 2: Billed Unmetered (BUAC) Unit Apparent Losses: 2.5 gal/conn/day 3: Customer Metering Inaccuracies (CMI) Unit Real LossesA : 19.0 gal/conn/day
Unit Real LossesB: 1,367 gal/mile/day
If entered above by user, targets will display on KPI gauges (see Dashboard) Are customer meters typically located at the curbstop/property line? AWWA Free Water Audit Software:

Worksheet
Mountain House
Jul 01 2022 - Jun 30 2023
Water Supplied Error Adjustments
2022 Fiscal
Real Losses:

WATER LOSSES:

Average length of customer service line has been set to zero and a data grading of 10 has been applied A weighted scale for the components of supply, consumption and water loss is included in the calculation of the Water Audit Data Validity Score *** The Water Audit Data Validity Score is in Tier III (51-70). See Dashboard tab for additional outputs. *** $/100 cubic feet (ccf)
$2,182,052
Total Annual Operating Cost
go to start page
NON-REVENUE WATER:

If entering an
Error Adjustment,
select under- or overregistration
WATER SUPPLIED:

AUTHORIZED CONSUMPTION:

Apparent Losses:

Click 'g' to determine data validity grade
Click 'n' to add notes
FWAS v6.0
American Water Works Association.

Copyright © 2020, All Rights Reserved.

To access definitions, click the input name
To edit water system info:

AWWA Free Water Audit Software v6.0 Worksheet 2

ATTACHMENT C
Item 8.2
Mountain House                                               Page 335 of 741 Water Audit Report for:

Audit Year:

All volumes to be entered as: MILLION GALLONS (US) PER YEAR WATER SUPPLIED choose entry option:

VOS Volume from Own Sources: n g 7 1,521.955 MG/Yr n g 10 0.00% percent MG/Yr over-registration VOSEA WI Water Imported: n g n/a 0.000 MG/Yr n g n/a 0.00% percent MG/Yr select….. WIEA WE Water Exported: n g n/a 0.000 MG/Yr n g n/a percent MG/Yr select….. WEEA 1,521.955 MG/Yr
.

AUTHORIZED CONSUMPTION
BMAC Billed Metered: n g 5 1,241.399 MG/Yr
BUAC Billed Unmetered: n g 10 12.000 MG/Yr
UMAC Unbilled Metered: n g n/a 0.000 MG/Yr choose entry option:

UUAC Unbilled Unmetered: n g 3 3.133 MG/Yr 0.25% default MG/Yr 24061 Default option selected for Unbilled Unmetered, with automatic data grading of 3 1,256.533 MG/Yr
WATER LOSSES 265.422 MG/Yr
Apparent Losses
Default option selected for Systematic Data Handling Errors, with automatic data grading of 3 choose entry option:

SDHE Systematic Data Handling Errors: n g 3 3.133 MG/Yr 0.25% default MG/Yr CMI Customer Metering Inaccuracies: n g 3 12.539 MG/Yr 1.00% percent MG/Yr under-registration UC Unauthorized Consumption: n g 3 3.133 MG/Yr 0.25% default MG/Yr Default option selected for Unauthorized Consumption, with automatic data grading of 3

18.806 MG/Yr
Real Losses
246.616 MG/Yr
265.422 MG/Yr

NON-REVENUE WATER
268.556 MG/Yr

SYSTEM DATA
Lm Length of mains: n g 8 102.7 miles (including fire hydrant lead lengths) Nc Number of service connections: n g 10 7,334 (active and inactive) Service connection density: 71 conn./mile main
Yes
Lp Average length of (private) customer service line: n g 10 ft (average distance between property line and meter) AOP Average Operating Pressure: n g 10 65.0 psi

COST DATA
CRUC Customer Retail Unit Charge: n g 9 $0.90
VPC Variable Production Cost: n g 9 $274.88 $/Million gallons $/yr (optional input) WATER AUDIT DATA VALIDITY TIER:
go to
dashboard
PRIORITY AREAS FOR ATTENTION TO IMPROVE DATA VALIDITY: KEY PERFORMANCE INDICATOR TARGETS:

Based on the information provided, audit reliability can be most improved by addressing the following components: OPTIONAL: If targets exist for the operational performance indicators, they can be input below:
1: Volume from Own Sources (VOS) Unit Total Losses: 21.4 gal/conn/day 2: Billed Metered (BMAC) Unit Apparent Losses: 2.5 gal/conn/day 3: Customer Metering Inaccuracies (CMI) Unit Real LossesA : 19.0 gal/conn/day
Unit Real LossesB: 1,367 gal/mile/day
If entered above by user, targets will display on KPI gauges (see Dashboard) Are customer meters typically located at the curbstop/property line? AWWA Free Water Audit Software:

Worksheet
Mountain House
Jul 01 2023 - Jun 30 2024
Water Supplied Error Adjustments
2023 Fiscal
Real Losses:

WATER LOSSES:

Average length of customer service line has been set to zero and a data grading of 10 has been applied A weighted scale for the components of supply, consumption and water loss is included in the calculation of the Water Audit Data Validity Score *** The Water Audit Data Validity Score is in Tier III (51-70). See Dashboard tab for additional outputs. *** $/100 cubic feet (ccf)
$3,416,205
Total Annual Operating Cost
go to start page
NON-REVENUE WATER:

If entering an
Error Adjustment,
select under- or
over-registration
WATER SUPPLIED:

AUTHORIZED CONSUMPTION:

Apparent Losses:

Click 'g' to determine data validity grade
Click 'n' to add notes
FWAS v6.0
American Water Works Association.

Copyright © 2020, All Rights Reserved.

To access definitions, click the input name
To edit water system info:

AWWA Free Water Audit Software v6.0 Worksheet 2

ATTACHMENT C
Item 8.2
Mountain House                                               Page 336 of 741 City of Mountain House
2025 Urban Water Management Plan
May 2026
E
Appendix E
Byron Bethany Irrigation District Water Services Agreement

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2025 Urban Water Management Plan
May 2026
F
Appendix F
Energy Use Tables

ATTACHMENT C
Item 8.2
Mountain House                                               Page 424 of 741 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
5,207 - 5,207
2,807,365 - 2,807,365
1,655 - 1,655
Quantity of Self-Generated Renewable Energy
0 kWh
Data Quality (Estimate, Metered Data, Combination of Estimates and Metered Data)Metered DataData Quality Narrative:

Narrative:(1) An estimate of the amount of energy used to extract or divert water supplies. 10631.2 (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. (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 though 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. 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:

Optional Submittal Table O-1B: Recommended Energy Reporting - SINGLE DELIVERY PRODUCT - TOTAL UTILITY APPROACH Only for Water Delivery Products Under the Urban Water Supplier's Operational Control
Sum of All Water Management
Processes Non-Consequential Hydropower
Volume of Water Entering Process
Energy Consumed (kWh)
Energy Intensity (kWh/vol. converted to MG)
DWR NOTES: Total Utility:The volume of water entered in the “Total Utility” column should equal the volume of water entering the distribution system (excluding recycled water); in most cases, this is the total volume calculated in UWMP Table 4-1: 2025 Actual Total Uses for Potable and Non-Potable Water. Note if recycled water is included in your Submittal Table 4-1, you must exclude it from your volume in this table. All power usage data has been provided by the Modesto Irrigation (MID) for water Treatment Plants and the two Pump Staions on Central Parkway and Great Valley Parkway.Energy is consumed during well pumping and treatment.NOTES: No additional notes.

ATTACHMENT
C
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Mountain House                                               Page 425 of 741 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 Collection / Conveyance Treatment Discharge / Distribution Total 1,843 1,916 0 3,759
1,484,456 0 0 1,484,456
2,472 0 0 1,212
0 0 0 0
0 0 0 0
0 0 0 0
Quantity of Self-Generated Renewable Energy related to recycled water and wastewater operations
0 kWh
Data Quality (drop down)
Metered Data
Data Quality Narrative:Narrative:NOTES: Watewater Energy Consumed was not split between collection and treatment and as such the total used throughout all systems is 1,484,456 kWh. Effort is being made to be able to differentiate and separate the two types of energy use categories.

Wastewater Energy Intensity (kWh/volume converted to MG) Volume of Wastewater Entering Process (volume units selected above) Wastewater Energy Consumed (kWh)
Volume of Recycled Water Entering Process (volume units selected above) Recycled Water Energy Consumed (kWh)
Recycled Water Energy Intensity (kWh/volume converted to MG) Optional Submittal Table O-2: Recommended Energy Reporting - WASTEWATER AND RECYCLED WATER Only for Water Delivery Products Under the Urban Water
Supplier's Operational Control
Water Management Process
Data from city electricity use reports.Energy is consumed at force mains, the lift station, and the WWTP.

ATTACHMENT
C
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Mountain House                                               Page 426 of 741 City of Mountain House
2025 Urban Water Management Plan
May 2026
G
Appendix G
2024 Consumer Confidence Report

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Mountain House                                               Page 427 of 741 1 City of Mountain House
Consumer Confidence Report 2024
Welcome to the 2024 Consumer Confidence Report!
The annual Consumer Confidence Report is a service provided by the City of Mountain House, a leader in providing safe, high-quality drinking water and water quality monitoring. We test the drinking water quality for many constituents as required by state and federal regulations. This report shows the results of our monitoring for the period of January 1 to December 31, 2024, and may include earlier monitoring data.

Water System Name: City of Mountain House (City)
Report Date: June 8, 2025
Type of Water Source(s) in Use: Surface Water – California Aqueduct Name/General Location of Source(s): Banks Pumping Station – Clifton Court Forebay, 94514 Drinking Water Source Assessment Information: California State Water Project Watershed Sanitary Survey 2021 update
Credit: Harvard Medical School, May 2023

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Mountain House                                               Page 428 of 741 2 Unit Definition
ND Not detectable at testing limit.
ppm parts per million or milligrams per liter (mg/L)
ppb parts per billion or micrograms per liter (µg/L)
ppt parts per trillion or nanograms per liter (ng/L)
ppq parts per quadrillion or picogram per liter (pg/L)
pCi/L picocuries per liter (a measure of radiation)
Importance of this Report Statement in Seven Non-English Languages
Language in Hindi: इस रिपोर्टमेंआपके पीनेके जल सेसम्बंधित महत्वपूर्टजानकािी हैl धहंदी मेंसहायता के धलए, City of Mountain House को 251 E. Main St. Mountain House, CA अथवा 209-831-2300 पि संपकट किेंl
Language in Hmong: Tsab ntawv no muaj cov ntsiab lus tseem ceeb txog koj cov dej haus. Thov hu rau City of Mountain House, 251 E. Main St. Mountain House, CA ntawm 209-831-2300 rau kev pab hauv lus Askiv.

Language in Mandarin: 这份报告含有关于您的饮用水的重要讯息。请用以下地址和电话联系City of Mountain House, 251 E. Main St. Mountain House, CA 以获得中文的帮助: 209-831-2300.

Language in Punjabi: ਐੱਸ ਰਿਪੋਟ ਰਿਚ ਤੁਿਾੜੇਪੀਣੇਦੇਿਾਿੇਮਹੱਤਿਪੂਿਨ ਸੂਚਨਾ ਹੈl ਪੰਜਾਬੀ ਰਿਚ ਮਦਦ ਲਈ, City of Mountain House ਨੂੰ 251 E. Main St. Mountain House, CA ਜਾਾਂ 209-831-2300 ਤੇਸੰਪਿਕ ਕਿੋ| Language in Spanish: Este informe contiene información muy importante sobre su agua para beber.

Favor de comunicarse City of Mountain House, a 251 E. Main St. Mountain House, CA – 209-831-2300 para asistirlo en español.

Language in Tagalog: Ang pag-uulat na ito ay naglalaman ng mahalagang impormasyon tungkol sa inyong inuming tubig. Mangyaring makipag-ugnayan sa City of Mountain House, 251 E. Main St.

Mountain House, CA o tumawag sa 209-831-2300 para matulungan sa wikang Tagalog.

Language in Vietnamese: Báo cáo này chứa thông tin quan trọng về nước uống của bạn. Xin vui lòng liên hệ City of Mountain House, 251 E. Main St. Mountain House, CA tại 209-831-2300 để được hỗ trợ giúp bằng tiếng Việt.

Units used for Water Quality Measurements

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Mountain House                                               Page 429 of 741 3 Drinking water, including bottled water, may reasonably be expected to contain at least small amounts of some contaminants.

The presence of contaminants does not necessarily indicate that water poses a health risk. More information about contaminants and potential health effects can be obtained by calling the United States Environmental Protection Agency’s (U.S. EPA) Safe Drinking Water Information Hotline (1-800-426-4791).

Some people may be more vulnerable to contaminants in drinking water than the general population. Immuno-compromised persons such as persons with cancer undergoing chemotherapy, persons who have undergone organ transplants, people with HIV/AIDS or other immune system disorders, some elderly, and infants can be particularly at risk from infections. These people should seek advice about drinking water from their health care providers. The U.S. EPA/ Centers for Disease Control (CDC) guidelines on appropriate means to lessen the risk of infection by
Cryptosporidium and other microbial contaminants are available from the Safe Drinking Water Hotline.

The sources of drinking water (both tap water and bottled water) include rivers, lakes, streams, ponds, reservoirs, springs, and wells. As water travels over the surface of the land or through the ground, it dissolves naturally occurring minerals and, in some cases, radioactive material, and can pick up substances resulting from the presence of animals or from human activity.

Contaminants in present in source water include:
• Microbial contaminants, such as viruses and bacteria that may come from sewage treatment plants, septic systems, agricultural livestock operations, and wildlife.
• Inorganic contaminants, such as salts and metals, which can be naturally occurring or result from urban stormwater runoff, industrial or domestic wastewater discharges, oil and gas production, mining, or farming.
• Pesticides and herbicides, which may come from a variety of sources such as agriculture, urban stormwater runoff, and residential uses.
• Organic chemical contaminants, including synthetic and volatile organic chemicals that are byproducts of industrial processes and petroleum production, and can also come from gas stations, urban stormwater runoff, and septic systems.
• Radioactive contaminants, which can be naturally occurring or be the result of oil and gas production and mining activities.

In order to ensure that tap water is safe to drink, the U.S. EPA and the and the State Water Quality Control Board (State Board) prescribe regulations that limit the amount of certain contaminants in water provided by public water systems. The U.S. Food and Drug Administration regulations and California law also establish limits for contaminants in bottled water that must provide the same protection for public health.

Public participation opportunities to discuss drinking water issues are held during regularly scheduled Board Meetings at the City of Mountain House, 251 E. Main St., Mountain House, CA 95391.

Meetings are held the 2nd & 4th Wednesday each month at 7p.m.

For more information, contact:

Steve Johnson (209) 362-9359
Karen Morgan (209) 831-5648
About This Report For Your Information
Terms That May Be Used in This Report
Level 1 Assessment
A Level 1 assessment is a study of the water system to identify potential problems and determine (if possible) why total coliform bacteria have been found in our water system.

Level 2 Assessment
A Level 2 assessment is a very detailed study of the water system to identify potential problems and determine (if possible) why an E. coli MCL violation has occurred and/or why total coliform bacteria have been found in our water system on multiple occasions.

Maximum Contaminant Level (MCL)
The highest level of a contaminant that is allowed in drinking water. Primary MCLs are set as close to the PHGs (or MCLGs) as is economically and technologically feasible. Secondary MCLs are set to protect the odor, taste, and appearance of drinking water.

Maximum Contaminant Level Goal (MCLG)
The level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs are set by the U.S. EPA.

Maximum Residual Disinfectant Level (MRDL)
The highest level of a disinfectant allowed in drinking water.

There is convincing evidence that addition of a disinfectant is necessary for control of microbial contaminants.

Maximum Residual Disinfectant Level Goal (MRDLG)
The level of a drinking water disinfectant below which there is no known or expected risk to health. MRDLGs do not reflect the benefits of the use of disinfectants to control microbial contaminants.

Primary Drinking Water Standards (PDWS)
MCLs and MRDLs for contaminants that affect health along with their monitoring and reporting requirements, and water
treatment requirements.

Public Health Goal (PHG)
The level of a contaminant in drinking water below which there is no known or expected risk to health. PHGs are set by the California Environmental Protection Agency.

Regulatory Action Level (AL)
The concentration of a contaminant which, if exceeded, triggers treatment or other requirements that a water system must follow.

Secondary Drinking Water Standards (SDWS)
MCLs for contaminants that affect taste, odor, or appearance of the drinking water. Contaminants with SDWSs do not affect the health at the MCL levels.

Treatment Technique (TT)
A required process intended to reduce the level of a
contaminant in drinking water.

Variances and Exemptions
Permissions from the State Board to exceed an MCL or not comply with a treatment technique under certain conditions.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 430 of 741 4 Tables 1, 2, 3, 4, 5, and 6 list all the drinking water contaminants that were detected during the most recent sampling for the constituent. The presence of these contaminants in the water does not necessarily indicate that the water poses a health risk. The State Board allows us to monitor for certain contaminants less than once per year because the concentrations of these contaminants do not change frequently. Some of the data, though representative of the water quality, are more than one year old. Any violation of an AL, MCL, MRDL, or TT, will be asterisked. Additional information regarding the violation is provided at the end of this report.

Table 1. Sampling Results Showing the Detection of Coliform Bacteria Microbiological
Contaminants
Highest No.
of
Detections
No. of
Months in
Violation
MCL MCLG Typical Source
of Bacteria
Health
Effects
E. coli 0 0 (a) 0 Human and
animal fecal
waste
(b)
(a) Routine and repeat samples are total coliform-positive and either is E. coli-positive, or system fails to take repeat samples following E. coli-positive routine sample or system fails to analyze total coliform-positive repeat sample for E. coli.
(b) E. coli are bacteria whose presence indicates that the water may be contaminated with human or animal waste. Human pathogens in these wastes can cause short-term effects, such as diarrhea, cramps, nausea, headaches, or other symptoms. They may pose a greater health risk for infants, young children, some of the elderly, and people with severely compromised immune systems.

Table 2. Sampling Results Showing the Detection of Lead and Copper Lead
and
Copper
Sample
Date
No. of
Samples
Collected
90th
Percentile
Level
Detected
No. Sites
Exceeding
AL
AL PHG Typical Source of
Contaminant
Lead
(ppb)
8-29-24
9-5-24
9-6-24
9-9-24
9-10-24
9-11-24
9-12-24
9-13-24
9-15-24
9-16-24
9-17-24
9-18-24
9-19-24
64 0.0 0 15 0.2 Internal corrosion of
household water
plumbing systems;
discharges from
industrial
manufacturers; erosion
of natural deposits
Copper
(ppm)
64 0.2 0 1.3 0.3 Internal corrosion of
household plumbing
systems; erosion of
natural deposits;
leaching from wood
preservatives
About Your Water Quality
Drinking Water Contaminants Detected

ATTACHMENT C
Item 8.2
Mountain House                                               Page 431 of 741 5 If present, elevated levels of lead can cause serious health problems, especially for pregnant women and young children. Lead in drinking water is primarily from materials and components associated with service lines and home plumbing. The City of Mountain House is responsible for providing high quality drinking water but cannot control the variety of materials used in plumbing components. When your water has been sitting for several hours, you can minimize the potential for lead exposure by flushing your tap for 30 seconds to 2 minutes before using water for drinking or cooking.

If you do so, you may wish to collect the flushed water and reuse it for another beneficial purpose, such as watering plants. If you are concerned about lead in your water, you may wish to have your water tested. Information on lead in drinking water, testing methods, and steps you can take to minimize exposure is available from the Safe Drinking Water Information Hotline (1-800-426-4791) or at https://www.epa.gov/lead.

Table 3. Sampling Results for Sodium and Hardness
Chemical or
Constituent
(and reporting
units)
Sample Date Level
Detected
Range of
Detections MCL PHG (MCLG)
Typical Source
of Contaminant
Sodium (ppm) 4-30-24 30 N/A None None Salt present in the water and is
generally naturally
occurring
Hardness (ppm) 4-30-24 65.4 N/A None None Sum of polyvalent cations present in
the water,
generally
magnesium and
calcium, and are
usually naturally
occurring
Lead

ATTACHMENT C
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Mountain House                                               Page 432 of 741 6 Table 4. Detection of Contaminants with a Primary Drinking Water Standard Chemical or
Constituent
(and reporting
units)
Sample
Date
Level
Detected
Range of
Detections
MCL
[MRDL]
PHG
(MCLG)
[MRDLG]
Typical Source
of Contaminant
Health
Effects
Haloacetic Acid
(Sum of 5
Haloacetic Acids)
(µg/L)
3-13-24 21
22 22
26 21-26
60 N/A
Byproduct of
drinking water
disinfection
(a)
6-5-24 23
25 26
26 23-26
9-4-24 7
13 13
16 7-16
12-4-24 18
19 21
23 18-23
Total
Trihalomethane
(TTHM)
(µg/L)
3-13-24 33
35 35
42 33-42
80 N/A
Byproduct of
drinking water
disinfection
(b)
6-30-24 23
26 27
28 23-28
9-4-24 26
26 27
27 26-27
12-4-24 38
42 44
46 38-46
Nitrate as N
(mg/L)
4/30/24 ND ND 10
(as N)
10 (as N)
Runoff and
leaching from
fertilizer use,
leaching from
septic tanks and
sewage; erosion
of natural
deposits
(c)
Nitrate+Nitrite as
N (mg/L)
4-30-24 ND ND 10
(as N)
10 (as N)
Runoff and
leaching from
fertilizer use,
leaching from
septic tanks and
sewage; erosion
of natural
deposits
(c)

ATTACHMENT C
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Mountain House                                               Page 433 of 741 7 Table 4. Detection of Contaminants with a Primary Drinking Water Standard (continued) Chemical or
Constituent
(and
reporting
units)
Sample
Date
Level
Detected
Range of
Detections
MCL
[MRDL]
PHG
(MCLG)
[MRDLG]
Typical
Source of
Contaminant
Health
Effects
Total Organic
Carbon (TOC)
(mg/L)
1-3-24
2-7-24
3-13-24
4-3-24
5-8-24
6-12-24
7-10-24
8-14-24
9-4-24
10-9-24
11-6-24
12-4-24

1.90 2.00

1.80 2.10

1.60 1.53

1.37 1.46

1.28 1.50

1.47 1.50

1.28 - 2.10 N/A N/A Various natural
and humanmade sources
N/A
Chloramines
(mg/L)
Jan-24
Feb-24
Mar-24
Apr-24
May-24
Jun-24
Jul-24
Aug-24
Sept-24
Oct-24
Nov-24
Dec-24

2.80 2.30

2.40 2.60

2.50 2.50

2.30 2.40

2.50 3.00

2.50 2.40

2.30 - 3.00 [MRDL =

4.0 (as Cl2)]
[MRDLG =
4 (as Cl2)]
Drinking water
disinfection
added for
treatment
(d)
(a) Some people who drink water containing haloacetic acids in excess of the MCL over many years may have an increased risk of getting cancer.
(b) Some people who drink water containing trihalomethanes in excess of the MCL over many years may experience liver, kidney, or central nervous system problems, and may have an increased risk of getting cancer.
(c) Infants below the age of six months who drink water containing nitrate in excess of the MCL may quickly become seriously ill and, if untreated, may die because high nitrate levels can interfere with the capacity of the infant’s blood to carry oxygen. Symptoms include shortness of breath and blueness of the skin. High nitrate levels may also affect the oxygen-carrying ability of the blood of pregnant women. (d) Some people who use water containing chloramines well in excess of the MRDL could experience irritating effects to their eyes and nose. Some people who drink water containing chloramines well in excess of the MRDL could experience stomach discomfort or anemia.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 434 of 741 8 Nitrate in drinking water at levels above 10 mg/L is a health risk for infants of less than six months of age. Such nitrate levels in drinking water can interfere with the capacity of the infant’s blood to carry oxygen, resulting in a serious illness; symptoms include shortness of breath and blueness of the skin. Nitrate levels above 10 mg/L may also affect the ability of the blood to carry oxygen in other individuals, such as pregnant women and those with certain specific enzyme deficiencies. If you are caring for an infant, or you are pregnant, you should ask advice from your health care provider.

Table 5. Detection of Contaminants with a Secondary Drinking Water Standard Chemical or
Constituent
(and reporting
units)
Sample
Date
Level
Detected
Range of
Detections SMCL1 PHG [MCLG]
Typical
Source of
Contaminant
Total Dissolved
Solids (TDS)
(mg/L)
4-30-24 170 N/A 500 N/A Runoff/leaching
from natural
deposits
Chloride (mg/L) 4-30-24 37 N/A 250 N/A Runoff/leaching
from natural
deposits;
seawater
influence
Sulfate (mg/L) 4-30-24 33.1 N/A 250 N/A Runoff/leaching from natural
deposits;
industrial
wastes
1 secondary maximum contaminant levels (SMCL) based on criteria found at eCFR :: 40 CFR Part 143 Subpart A -- National Secondary Drinking Water Regulations
Table 6. Detection of Unregulated Contaminants
Chemical or
Constituent (and
reporting units)
Sample
Date
Level
Detected
Range of
Detections
Notification
Level (µg/L)
Health
Effects
11-chloroeicosafluoro3-oxaundecane-1-
sulfonic acid (11ClPF3OUdS)
3-26-24
5-21-24
8-20-24
11-21-24
ND N/A 0.005 N/A
1H, 1H, 2H, 2Hperfluorodecane
sulfonic acid (8:2FTS)
3-26-24
5-21-24
8-20-24
11-21-24
ND N/A 0.005 N/A
Nitrates

ATTACHMENT C
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Mountain House                                               Page 435 of 741 9 Table 6. Detection of Unregulated Contaminants (continued) Chemical or
Constituent (and
reporting units)
Sample
Date
Level
Detected
Range of
Detections
Notification
Level (µg/L)
Health
Effects
1H, 1H, 2H, 2Hperflurohexane sulfonic
acid (4:2FTS)
3-26-24
5-21-24
8-20-24
11-21-24
ND N/A 0.003 N/A
1H, 1H, 2H, 2Hperfluorooctane
sulfonic acid (6:2FTS)
3-26-24
5-21-24
8-20-24
11-21-24
ND N/A 0.005 N/A
4, 8-dioxa-3Hperflurononanoic acid
(ADONA)
3-26-24
5-21-24
8-20-24
11-21-24
ND N/A 0.003 N/A
9-chlorohexadecafluro3-oxanonane-1-sulfonic
acid (9Cl-PF3ONS)
3-26-24
5-21-24
8-20-24
11-21-24
ND N/A 0.002 N/A
Hexafluoropropylene
oxide dimer acid
(HFPO-DA)(GenX)
3-26-24
5-21-24
8-20-24
11-21-24
ND N/A 0.005 N/A
Nonafluoro-3,6-
dioxaheptanoic acid
(NFDHA)
3-26-24
5-21-24
8-20-24
11-21-24
ND N/A 0.02 N/A
Perfluro (2-
ethoxyethane) sulfonic
acid (PFEESA)
3-26-24
5-21-24
8-20-24
11-21-24
ND N/A 0.003 N/A
Perfluoro-3-
methooxypropanoic
acid (PFMPA)
3-26-24
5-21-24
8-20-24
11-21-24
ND N/A 0.004 N/A
Perfluro-4-
methoxybutanoic acid
(PFMBA)
3-26-24
5-21-24
8-20-24
11-21-24
ND N/A 0.003 N/A
Perflurobutanesulfonic
acid (PFBS)
3-26-24
5-21-24
8-20-24
11-21-24
ND N/A 0.003 N/A
Perflurorobutanoic acid
(PFBA)
3-26-24
5-21-24
8-20-24
11-21-24
ND N/A 0.005 N/A

ATTACHMENT C
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Mountain House                                               Page 436 of 741 10 Table 6. Detection of Unregulated Contaminants (continued) Chemical or
Constituent (and
reporting units)
Sample
Date
Level
Detected
Range of
Detections
Notification
Level (µg/L)
Health
Effects
Perfluorodecanoic acid
(PFDA)
3-26-24
5-21-24
8-20-24
11-21-24
ND N/A 0.005 N/A
Perfluorodeconoic acid
(PFDoA)
3-26-24
5-21-24
8-20-24
11-21-24
ND N/A 0.003 N/A
Perfluoroheptanesulfonic
acid (PFHpS)
3-26-24
5-21-24
8-20-24
11-21-24
ND N/A 0.003 N/A
Perfluoroheptanoic acid
(PFHpA)
3-26-24
5-21-24
8-20-24
11-21-24
ND N/A 0.003 N/A
Perfluorohexanesulfonic
acid (PFHxS)
3-26-24
5-21-24
8-20-24
11-21-24
ND N/A 0.003 N/A
Perfluorohexanoic acid
(PFHxA)
3-26-24
5-21-24
8-20-24
11-21-24
ND N/A 0.003 N/A
Perfluorononanoic acid
(PFNA)
3-26-24
5-21-24
8-20-24
11-21-24
ND N/A 0.004 N/A
Perfluorooctanesulfonic
acid (PFOS)
3-26-24
5-21-24
8-20-24
11-21-24
ND N/A 0.004 N/A
Perfluorooctanoic acid
(PFOA)
3-26-24
5-21-24
8-20-24
11-21-24
ND N/A 0.004 N/A
Perfluoropentanesulfonic
acid (PFPeS)
3-26-24
5-21-24
8-20-24
11-21-24
ND N/A 0.004 N/A

ATTACHMENT C
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Mountain House                                               Page 437 of 741 11 Table 6. Detection of Unregulated Contaminants (continued) Chemical or
Constituent (and
reporting units)
Sample
Date
Level
Detected
Range of
Detections
Notification
Level (µg/L)
Health
Effects
Perfluoropentanoic acid
(PFPeA)
3-26-24
5-21-24
8-20-24
11-21-24
ND N/A 0.003 N/A
Perfluoroundecanoic acid
(PFUnA)
3-26-24
5-21-24
8-20-24
11-21-24
ND N/A 0.002 N/A
N-ethyl
perfluorooctanesulfon
amidoacetic acid
(NEtFOSAA)
2-27-24
5-21-24
8-20-24
11-21-24
ND N/A 0.005 N/A
N-methyl
perfluorooctanesulfonami
doacetic acid
(NMeFOSAA)
2-27-24
5-21-24
8-20-24
11-21-24
ND N/A 0.006 N/A
Perfluorotetradecoanoic
acid (PFTA)
2-27-24
5-21-24
8-20-24
11-21-24
ND N/A 0.008 N/A
Perfluorotridecanoic acid
(PFTrDA)
2-27-24
5-21-24
8-20-24
11-21-24
ND N/A 0.007 N/A
lithium 2-27-24
5-21-24
8-20-24
11-21-24
ND N/A 9 N/A
Table 7. Violation(s) of a MCL, MRDL, AL, TT or Monitoring and Reporting Requirement(s)
Violation Explanation Duration
Actions Taken
to Correct
Violation
Health Effects
Language

N/A N/A N/A N/A N/A
Summary Information for Violations of a MCL, MRDL,
AL, TT, or Monitoring and Reporting Requirements

ATTACHMENT C
Item 8.2
Mountain House                                               Page 438 of 741 12 This water system relies on surface water as a source of water, not groundwater. Thus, Tables 8 and 9, as well as any summary information for fecal indicator-positive groundwater source samples, uncorrected significant deficiencies, or groundwater violations, or groundwater treatment technologies are not applicable in this report.

Table 10. Sampling Results Showing Treatment of Surface Water Sources Treatment Technique (a) (Type of
approved filtration technology
used)
Conventional Filtration Technology
Turbidity Performance
Standards (b) (that must be met
through the water treatment
process)
Turbidity of the filtered water must:
1 – Be less than or equal to .30 NTU in 95% of
measurements in a month.
2 – Not exceed 1.0 NTU for more than eight
consecutive hours.
3 – Not exceed 1.0 NTU at any time.

Lowest monthly percentage of
samples that met Turbidity
Performance Standard No. 1
100
Highest single turbidity
measurement during the year

0.21 Number of violations of any
surface water treatment
requirements
0 (a) A required process intended to reduce the level of a contaminant in drinking water. (b) Turbidity (measured in NTU) is a measurement of the cloudiness of water and is a good indicator of water quality and filtration performance. Turbidity results which meet performance standards are considered to be in compliance with filtration requirements.

Table 11. Violation of Surface Water TT
Violation Explanation Duration
Actions Taken
to Correct
Violation
Health Effects
Language

N/A N/A N/A N/A N/A
For Water Systems Providing Surface Water as a Source of Drinking Water
Summary Information for Violation(s) of a Surface Water TT For Water Systems Providing Groundwater as a Source of
Drinking Water

ATTACHMENT C
Item 8.2
Mountain House                                               Page 439 of 741 13 If a water system is required to comply with a Level 1 or Level 2 assessment requirement that is not due to an E. coli MCL violation, include the following information below [22 CCR section 64481(n)(1)].

Coliforms are bacteria that are naturally present in the environment and are used as an indicator that other, potentially harmful, waterborne pathogens may be present or that a potential pathway exists through which contamination may enter the drinking water distribution system. When this occurs, we are required to conduct assessment(s) to identify problems and to correct any problems that were found during these assessments.

The water system shall include the following statements, as appropriate:

If the water system failed to complete all the required assessments or correct all identified sanitary defects, the water system is in violation of the treatment technique requirement and shall include the following statements, as appropriate: N/A Level 1 or Level 2 Assessment Requirement not due to an E. coli MCL violation
During the past year, we were required to conduct 0 Level 1 assessment(s). Zero (0) Level 1 assessment(s) were completed. In addition, we were required to conduct 0 corrective actions. We completed 0 of these actions.

During the past year 0 Level 2 assessments were required to be completed for our water system. Zero (0) Level 2 assessments were completed. In addition, we were required to take 0 corrective actions. We completed 0 of these actions.

E. coli are bacteria whose presence indicates that the water may be contaminated with human or animal waste. Human pathogens in these wastes can cause short-term effects, such as diarrhea, cramps, nausea, headaches, or other symptoms. They may pose a greater health risk for infants, young children, the elderly, and people with severely compromised immune systems. We DID NOT find E. coli bacteria, which would have indicated the need to look for potential problems in water treatment or distribution. When this occurs, we are required to conduct assessment(s) identifying problems and to correct any problems that were found during these assessments.

We were NOT required to complete a Level 2 assessment. In addition, we were NOT required to take corrective actions.

Summary Information for Revised Total Coliform Rule Level 1 and Level 2 Assessment Requirements
Level 2 Assessment Requirement due to an E. coli MCL Violation Summary Information for Operating Under a Variance or Exemption N/A

ATTACHMENT C
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Mountain House                                               Page 440 of 741 City of Mountain House
2025 Urban Water Management Plan
May 2026
H
Appendix H
Water Shortage Contingency Plan

ATTACHMENT C
Item 8.2
Mountain House                                               Page 441 of 741 City of Mountain House
Water Shortage Contingency Plan
DRAFT
JUNE 2026
Prepared for:

CITY OF MOUNTAIN HOUSE
251 East Main Street
Mountain House, CA 95391
Prepared by:

BLACK WATER CONSULTING ENGINEERS, INC.
602 Lyell Drive
Modesto, CA 95356
(209) 322-1820

ATTACHMENT C
Item 8.2
Mountain House                                               Page 442 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
i

TABLE OF CONTENTS
1 Introduction .......................................................................................................................................... 1 2 Water Supply Reliability Analysis .......................................................................................................... 3

2.1 Seismic Risk Assessment and Mitigation Plan .............................................................................. 4 3 Annual Water Supply and Demand Assessment Procedures ............................................................... 5

3.1 Decision-Making Process .............................................................................................................. 6

3.2 Data and Methodologies............................................................................................................... 6

3.2.1 Current Year Unconstrained Customer Demand .................................................................. 6

3.2.2 Current Year Available Supply ............................................................................................... 7

3.2.3 Infrastructure Considerations ............................................................................................... 7

3.2.4 Evaluation Criteria ................................................................................................................. 7

3.2.5 Water Supply ......................................................................................................................... 7 4 Six Standard Water Shortage Levels ..................................................................................................... 8 5 Shortage Response Actions ................................................................................................................ 10

5.1 Supply Augmentation Actions ..................................................................................................... 11

5.2 Demand Reduction Actions ........................................................................................................ 12

5.3 Operational Changes ................................................................................................................... 23

5.4 Additional Mandatory Prohibitions ............................................................................................ 23

5.5 Emergency Response Plan .......................................................................................................... 23

5.6 Seismic Risk Assessment and Mitigation Plan ............................................................................ 23

5.7 Shortage Response Action Effectiveness .................................................................................... 24 6 Communication Protocols .................................................................................................................. 26

6.1 Communication for Foreseeable Events ..................................................................................... 26

6.2 Communication for Unforeseeable Events ................................................................................. 27 7 Compliance and Enforcement ............................................................................................................ 28

7.1 Procedures .................................................................................................................................. 28

7.2 Appeal Process ............................................................................................................................ 29 8 Legal Authorities ................................................................................................................................. 31 9 Financial Consequences of WSCP ....................................................................................................... 33 10 Monitoring and Reporting .................................................................................................................. 35 11 WSCP Refinement Procedures ............................................................................................................ 36 12 Special Water Feature Distinction ...................................................................................................... 37 13 Plan Adoption, Submittal and Availability .......................................................................................... 38 14 References .......................................................................................................................................... 39

LIST OF TABLES
Table 3-1 – AWSDA Key Responsibilities ...................................................................................................... 6 Table 4-1 – Water Shortage Contingency Plan Levels (DWR Table 8-1) ....................................................... 9 Table 5-1 – Supply Augmentation and Other Actions (DWR Table 8-2) ..................................................... 12 Table 5-2 – Demand Reduction Actions (DWR Table 8-3) .......................................................................... 13

ATTACHMENT C
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Mountain House                                               Page 443 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
ii

LIST OF FIGURES
Figure 3-1 Example AWSDA and AWSAR Timeline ....................................................................................... 6

APPENDICES
Appendix A – San Joaquin County Local Hazard Mitigation Plan Appendix B – Notices to Public and Public Outreach Efforts Appendix C – City Resolution Adopting WSCP

ATTACHMENT C
Item 8.2
Mountain House                                               Page 444 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
iii

LIST OF ACRONYMS AND ABBREVIATIONS
AMI Advanced Metering Infrastructure
AMR Automated Meter Reading
AWIA America’s Water Infrastructure Act
AWSDA Annual Water Supply and Demand Assessment
AWSAR Annual Water Shortage Assessment Report
City City of Mountain House
MMC City of Mountain House Municipal Code
CWC California Water Code
DWR Department of Water Resources
ERP Emergency Response Plan
FEMA Federal Emergency Management Agency
gpcd Gallons per Capita per Day
LHMP Local Hazard Mitigation Plan
MG Million Gallons
PIO Public Information Officer
RRA Risk and Resilience Assessment
TCC Technical Command Center
UWMP Urban Water Management Plan
WSCP Water Shortage Contingency Plan

ATTACHMENT C
Item 8.2
Mountain House                                               Page 445 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
1 1 Introduction
Water agencies across California face increasing challenges in reliably meeting customer demands due to a combination of population growth, climate change, prolonged droughts, regulatory constraints, and the potential for catastrophic natural or human-caused events. A water shortage occurs when the available water supply is insufficient to meet normally expected customer water use at a given point in time. Recent history, including the severe statewide drought from 2012 through 2016, demonstrated the vulnerability of many water systems and underscored the importance of proactive planning and preparedness.

In response to these challenges, the California State Legislature enacted Assembly Bill 1668 and Senate Bill 606, collectively known as the 2018 Water Conservation Legislation. Among other requirements, this legislation mandates that Urban Water Management Plans (UWMPs) include a Water Shortage Contingency Plan (WSCP) pursuant to California Water Code (CWC) Section 10632. The WSCP establishes a comprehensive, actionable framework for evaluating water supply reliability and implementing response actions during varying levels of water shortage. While the WSCP is submitted as part of the 2025 UWMP, it is structured as a stand-alone document that may be updated or amended independently, as needed, without requiring amendment of the UWMP itself.

Water shortage contingency planning is a strategic and forward-looking process intended to prepare for and respond to both foreseeable and unforeseeable water supply disruptions. Even where the probability of shortage appears low, a WSCP serves as an essential component of drought and emergency management policy by improving preparedness and reducing the severity of impacts should shortages occur. Drought, regulatory actions, infrastructure failures, seismic events, wildfires, floods, and other natural or man-made disasters may occur with little warning, making advanced planning critical.

The WSCP functions as the Supplier’s operational manual for managing water shortages. It enables near real-time assessment of water supply availability and provides structured, pre-planned response actions aligned with defined levels of shortage. During drought or emergency conditions, the WSCP serves as a roadmap for decision-makers, staff, and the public, allowing for predictable, transparent, and accountable implementation of water shortage response measures. Importantly, Water Code Section 10632.3 directs the State Water Resources Control Board, during a drought emergency, to defer to locally adopted WSCPs to the extent practicable, reinforcing the role of the WSCP in supporting local decision-making.

The WSCP is developed based on a thorough understanding of the Supplier’s water supply reliability, including existing and projected demands, hydrologic variability, regulatory constraints, infrastructure vulnerabilities, and the availability of alternative or supplemental supplies. By anticipating both shortterm and long-term risks to supply, the WSCP identifies feasible and locally appropriate actions to manage shortages, minimize service disruptions, and protect public health and safety. In addition, the analysis and response framework documented in the WSCP may support justification for future projects, policies, and programs intended to reduce vulnerability to water shortages.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 446 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
2 Pursuant to CWC Section 10632, the WSCP is required to include the following elements:
• Key attributes of the water supply reliability analysis conducted pursuant to CWC Section 10632(a)(1), which evaluates the Supplier’s ability to meet demands under varying hydrologic and operational conditions.
• Six standard water shortage levels corresponding to progressive shortages of up to 10, 20, 30, 40, and 50 percent, and shortages greater than 50 percent. [CWC Section 10632(a)(3)(A)] • Locally appropriate shortage response actions for each shortage level, including supply augmentation, demand reduction, operational changes, and mandatory water-use prohibitions, along with estimates of the extent to which each action addresses the supply-demand gap. [CWC Section 10632(a)(4)]
• Procedures for conducting an Annual Water Supply and Demand Assessment (AWSDA), including the data and methods used to evaluate supply reliability. Urban water suppliers are required to submit an Annual Water Shortage Assessment Report (AWSAR) to the California Department of Water Resources (DWR) by July 1 of each year, beginning in the year following adoption of the 2020 UWMP. [CWC Sections 10632(a)(2) and 10632.1]
• Communication protocols and procedures to inform customers, the public, and government entities of current or anticipated water shortages and associated response actions. [CWC Section 10632(a)(5)]
• Monitoring and reporting procedures to ensure appropriate data collection, track customer compliance, evaluate the effectiveness of response actions, and meet applicable state reporting requirements. [CWC Section 10632(a)(9)]
• A re-evaluation and improvement process to periodically assess the performance and functionality of the WSCP and to make adjustments based on observed conditions, monitoring results, and evolving risks. [CWC Section 10632(a)(10)]

ATTACHMENT C
Item 8.2
Mountain House                                               Page 447 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
3 2 Water Supply Reliability Analysis
Legal Requirements:

Water Code Section 10632(a)(1)
The analysis of water supply reliability conducted pursuant to Section 10635.

Water Code Section 10632.5(a)
In addition to the requirements of paragraph (3) of subdivision (a) 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.

In accordance with CWC Section 10632(a)(1), this section presents findings from the City of Mountain House (City) water system reliability analysis and identifies the key factors that may contribute to future water shortage conditions. This evaluation incorporates projected water use trends from Chapter 4 of the UWMP, the inventory of current and planned water supply sources outlined in Chapter 6, and the water supply reliability and drought risk assessments presented in Chapter 7. The reliability assessment spans the years 2030 through 2050, while the drought risk assessment covers the five-year period from 2026 to 2030. Together, these elements provide a comprehensive understanding of the City’s water resource capacity and its preparedness to respond to potential shortage scenarios.

When water supply shortfalls are anticipated or observed, the City may declare a water shortage level in accordance with this WSCP, as described in Section 4. In response to identified reliability challenges, the City and the Byron Bethany Irrigation District continue to evaluate additional supply, operational, and water management strategies, as documented in Chapter 7 of the City’s 2025 UWMP.

In addition to hydrologic variability, water supply reliability may be affected by factors beyond the City’s direct control, including statewide water supply conditions, actions taken by upstream or neighboring agencies, regulatory changes, and emergency events. A water shortage condition occurs when the available potable water supply is insufficient to meet ordinary water demands necessary to protect public health and safety. While some water shortages may be foreseeable through planning and monitoring, unforeseen or sudden emergency events, such as power outages, infrastructure failures, or seismic events, may also disrupt water supplies.

The City’s water supply reliability may be influenced by the following factors:
• Local surface water availability from the Old River,
• Vulnerability of Sacramento–San Joaquin Delta conveyance facilities to seismic events, • Changing environmental and regulatory requirements, and • Climate change and associated hydrologic variability.

The City’s 2025 UWMP evaluated the long-term (20-year) and near-term (5-year) supply reliability of the City’s water system, including consideration for a normal year, single dry year, and a 5-year dry period and concluded that the City can reliably meet its projected water demands.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 448 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
4 2.1 Seismic Risk Assessment and Mitigation Plan
Refer to Section 5.6 of this WSCP for the details related to the City’s seismic risk assessment and mitigation plan to assess the vulnerability of each of the various facilities of water system.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 449 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
5 3 Annual Water Supply and Demand Assessment Procedures Legal Requirements:

Water Code 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 Water Code Section 10632(a)(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.
(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.

Water Code 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.

CWC Section 10632.1 requires the City to conduct an AWSDA on or before July 1 of each year and to submit an AWSAR to the California DWR by July 1 annually. The purpose of the AWSDA and AWSAR is to evaluate near-term water supply reliability for the upcoming year and to ensure that appropriate water shortage response actions are identified and implemented in a timely manner, if warranted.

This section of the WSCP describes the procedures used by the City to prepare the AWSDA and AWSAR.

These procedures are intended to establish a clear, consistent process for the annual evaluation of water supply and demand conditions, including the timing, data sources, analytical steps, and decision-making framework used to determine water supply reliability and potential shortage conditions.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 450 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
6 3.1 Decision-Making Process
The City is responsible for preparation, obtaining formal approval, and submitting the AWSAR to the DWR.

Key responsibilities for preparation of the AWSDA and AWSAR are listed in Table 3-1. Early in the process, the key team members will be selected and assigned responsibilities to ensure accurate and timely completion of the documents. Each AWSAR should include a summary of the key members involved and their roles and responsibilities.

Table 3-1 – AWSDA Key Responsibilities
# Activity
1 Convene AWSDA and AWSAR team
2 Information collection and review (see Section 3.2, Key Data Inputs and Methodologies) 3 Prepare draft AWSAR
4 Finalize AWSAR
5 Submit AWSAR to DWR
An example timeline for the decision-making process is provided in Figure 3-1. Actual dates for each activity may vary, however the AWSAR is required to be formally approved and submitted to DWR by July 1 each year.

Figure 3-1 Example AWSDA and AWSAR Timeline

3.2 Data and Methodologies
In preparing the AWSDA, the City will apply the methodologies and evaluation criteria described in this section to assess water supply reliability for the current year and one subsequent dry year. The key data inputs and analytical methods used in this assessment are described below.

3.2.1 Current Year Unconstrained Customer Demand
Unconstrained customer demand for the current year will be developed in this section. The methodology for the calculations should be described in detail. References for the sources and assumptions used should be provided. Unconstrained customer demands for subsequent years may be calculated and included.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 451 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
7 Various methods could be used to calculate unconstrained customer demand. The method should be consistent with previous City documents, including the 2025 UWMP. If an alternative method is used, reasons for the change in approach shall be provided. The most common methods will either involve the use of population projections and a per capita water demand or water demand factors for various types of land uses and estimates for developed areas, by land use type.

3.2.2 Current Year Available Supply
This section of the assessment will summarize the projected available water supply for the current year based on the information provided in previous sections of the Annual Assessment. The evaluation criteria will be applied to determine if the available water supply is sufficient to meet unconstrained customer demands.

3.2.3 Infrastructure Considerations
This section should include an evaluation of how the City's infrastructure capabilities and constraints may affect its ability to deliver supplies to meet customer demand in the coming year. Anticipated capital projects that may influence capabilities, such as repairs that may constrain capabilities (e.g., planned treatment plant upgrades) or new projects that may add capacity (e.g., a new groundwater well or system intertie), should be described.

3.2.4 Evaluation Criteria
The Annual Assessment will define the specific criteria the City will use each year to evaluate whether available water supplies are sufficient to meet projected demand and to determine whether a water shortage condition exists.

3.2.5 Water Supply
The Annual Assessment will quantify each source of water supply and describe the methods and assumptions used to estimate available supplies.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 452 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
8 4 Six Standard Water Shortage Levels
Legal Requirements:

Water Code Section 10632(a)(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.

To provide a consistent regional and statewide framework for communicating the severity of water supply shortage conditions, the 2018 Water Conservation Legislation requires urban water suppliers to define six standard water shortage levels corresponding to progressive ranges of water supply shortages. CWC Section 10632(a)(3) requires these shortage levels to be based on the supplier’s water supply conditions and may consider factors such as percentage reductions in available water supply, changes in groundwater levels, changes in surface water elevations, land subsidence, or other hydrologic or local conditions indicative of the water supply available for use.

In accordance with these requirements, the City adopted the six standard water shortage levels established by the California DWR for inclusion in WSCPs in 2025. These standard shortage levels correspond to progressive water supply shortages of up to 10 percent, 20 percent, 30 percent, 40 percent, 50 percent, and greater than 50 percent from normal reliability conditions. The standard water shortage levels used by the City are consistent with those presented in Table 4-1 (DWR Table 8-1). The water shortage levels and corresponding response actions adopted by the City apply to both foreseeable water supply shortages, such as drought or regulatory curtailments, and unforeseeable supply interruptions, including infrastructure failures or other emergency conditions.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 453 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
9 Table 4-1 – Water Shortage Contingency Plan Levels (DWR Table 8-1) Submittal Table 8-1: Cross-reference for Standard vs
Supplier Shortage Levels
Water Code Section 10632(a)(3)(B)

Check the box if the Supplier uses the
Standard six levels of water shortage.

Proceed to the next table.

Standard
Shortage
Levels
Percent
Shortage
Range
Suppliers
Shortage
Levels
Percent
Shortage
Range
1 Up to 10%
2 Up to 20%
3 Up to 30%
4 Up to 40%
5 Up to 50%
6 >50%
NOTES: No additional notes.

Each water shortage level provides the basis for implementing graduated water shortage response actions, as described in subsequent sections of this WSCP.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 454 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
10 5 Shortage Response Actions
Legal Requirements:

Water Code Section 10632 (a)(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.
(D) Additional, mandatory prohibitions against specific water use practices that are in addition to statemandated 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.

Water Code 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 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.

CWC Section 10632(a)(4) requires shortage response actions that align with the shortage levels defined in Table 4-1 (DWR Table 8-1) and include locally appropriate supply augmentation actions, demand reduction actions, operational changes, and additional mandatory prohibitions against specific water use practices. An estimate of the extent to which the gap between supplies and demand will be reduced by implementation of the actions must be provided.

The City intends to implement a balanced and flexible approach to water shortage response, integrating demand reduction, supply augmentation, and operational adjustments to address the identified water supply shortfall and the associated shortage level. Response actions will be selected and implemented to reduce the gap between available water supplies and projected demands and to achieve the water use reduction objectives associated with the declared water shortage level.

The City relies on system-wide water metering to monitor water production and customer water use and to evaluate the effectiveness of shortage response actions. The water system is fully metered, allowing the City to compare current water use to historical use and to established demand reduction targets. A significant portion of the system is equipped with cloud-based advanced metering infrastructure (AMI), enabling near real-time monitoring of water use. Remaining meters are read on a regular basis to support

ATTACHMENT C
Item 8.2
Mountain House                                               Page 455 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
11 ongoing assessment of water demand and response effectiveness. The City will continue to expand AMI deployment as equipment availability and system conditions allow.

Water production and customer water use may be evaluated by customer sector or individual account and compared to prior periods to assess trends and compliance with demand reduction goals. This ongoing monitoring allows the City to adjust shortage response actions, as needed, to balance water demands with available supplies. For example, the City may increase public outreach efforts or enhance enforcement of water use restrictions if demand reduction targets are not being met. Conversely, outreach frequency or enforcement intensity may be reduced if demand reductions exceed established targets.

The shortage response actions described in subsequent sections are intended to provide the City with a range of tools to respond effectively to water shortage conditions. Response actions are initiated at the shortage levels identified and may continue or intensify at higher shortage levels. Because the City may continuously monitor conditions and adjust response actions over time, the extent to which individual actions reduce the gap between water supply and demand may be difficult to quantify precisely and is therefore provided as an estimate. Certain response actions, such as public outreach, education, and enforcement, support the effectiveness of other measures and may not have a directly quantifiable water savings when implemented independently.

5.1 Supply Augmentation Actions
The City maintains approximately 12 million gallons (MG) of potable water storage within its service area to support normal system operations and to mitigate the effects of short-term water supply interruptions lasting several days. This storage capacity provides operational flexibility during localized or temporary supply disruptions.

During a declared water shortage emergency, the City may pursue temporary supply augmentation measures, including the purchase of supplemental water supplies from regional water suppliers, to reduce the gap between available water supply and projected demands. Similar measures were implemented during the 2012–2016 drought and may be considered again, subject to availability, contractual arrangements, and operational feasibility.

Additional supply augmentation and other actions that the City may implement during water shortage emergencies are summarized in Table 5-1 (DWR Table 8-2). These actions are intended to complement demand reduction and operational measures and may be implemented individually or in combination, depending on the severity and duration of the water shortage condition.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 456 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
12 Table 5-1 – Supply Augmentation and Other Actions (DWR Table 8-2) Submittal Table 8-2 Retail: Supply Augmentation and Other Actions Water Code Section 10632(a)(4)(A),(C) and (E)
Yes Is the Supplier completing this table using the standard six levels? (yes/no) Shortage
Level
Supply Augmentation
Methods and Other
Actions by Water Supplier
Drop down list
These are the only categories
that will be accepted by the
WUEdata online submittal tool
How much is this going to
reduce the shortage gap? Additional Explanation or
Reference
(OPTIONAL) Volume or
Percentage
Drop down
Shortage Gap
Reduction
Value
(May be a range)
Add additional rows as needed
1 Other Actions (describe) Percentage 0 No action in Level 1. 2 Expand Public
Information Campaign Percentage 1-10%
3 Transfers Percentage 1-10% Purchase additional water
supplies from other agencies
4 Transfers Percentage 1-10% Purchase additional water
supplies from other agencies
5 Transfers Percentage 1-10% Purchase additional water
supplies from other agencies
6 Transfers Percentage 1-10% Purchase additional water
supplies from other agencies
DWR NOTES: Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3.

NOTES: Shortage Level 2, Expand Public Information Campaign is going to reduce the shortage gap by promoting the effectiveness of the demand reduction actions to be discussed in the following section.

Shortage Level 3-6, Transfers, will reduce the shortage gap up to the full shortage amount hence the Shortage Gap Reduction Value as a range. For example: If the City is mandating Shortage Level 3 actions and are only reducing the amount of water usage by 27%, this supplemental augmentation method will assist in reaching the specified reduction value.

5.2 Demand Reduction Actions
During water shortage conditions, the City will reduce customer water demand through implementation of the demand reduction actions identified in Table 5-2 (DWR Table 8-3). The City of Mountain House Municipal Code (MMC), Title 5, Division 3, will need to be updated to incorporate the demand reduction actions identified in Table 5-2 (DWR Table 8-3). Demand reduction actions are organized by water shortage level, and each action includes an estimate of the extent to which its implementation is expected to reduce the gap between available water supply and projected demand.

For each demand reduction action, Table 5-2 (DWR Table 8-3) also identifies whether compliance measures, such as penalties, charges, or other enforcement mechanisms, may be applied. Demand

ATTACHMENT C
Item 8.2
Mountain House                                               Page 457 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
13 reduction actions are initiated at the water shortage levels identified and may continue to be implemented or intensified at higher shortage levels, as appropriate.

Table 5-2 – Demand Reduction Actions (DWR Table 8-3)
Submittal Table 8-3 Retail: Demand Reduction Actions
Water Code Section 10632(a)(4)(B) and (E)
Yes Is the Supplier completing this table using the standard six levels? (yes/no) Shortage
Level
Demand
Reduction
Actions
Drop down list
These are the
only categories
that will be
accepted by the
WUEdata online
submittal tool.

Select those that
apply.

How much is this going to
reduce the shortage gap?
Additional Explanation
or Reference
(OPTIONAL)
Penalty,
Charge, or
Other
Enforcement?
For Retail
Suppliers Only
Drop Down List
Volume or
Percentage
Drop down
Shortage
Gap
Reduction
Value
(May be a
range)
Add additional rows as needed
1 Landscape -
Limit landscape
irrigation to
specific times
Volume 22 gpcd
Exterior irrigation at
public, private, and
commercial locations
shall be subject to timeof-day restrictions.

Irrigation in non-public
areas is prohibited
between the hours of
11:00 a.m. and 6:00 p.m.
during the period from
May 1 through October

1. Irrigation in public
areas is prohibited
between the hours of
6:00 a.m. and 7:00 p.m.

No
1 Other -
Customers must
repair leaks,
breaks, and
malfunctions in
a timely
manner
Volume
Supports
other
demand
reduction
actions
To allow the escape of
water through leaks,
breaks or malfunction
within the customer's
plumbing or distribution
system for any period of
time within which such
break or leak should
reasonably have been
discovered and
No

ATTACHMENT C
Item 8.2
Mountain House                                               Page 458 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
14 Submittal Table 8-3 Retail: Demand Reduction Actions Water Code Section 10632(a)(4)(B) and (E)
Yes Is the Supplier completing this table using the standard six levels? (yes/no) Shortage
Level
Demand
Reduction
Actions
Drop down list
These are the
only categories
that will be
accepted by the
WUEdata online
submittal tool.

Select those that
apply.

How much is this going to
reduce the shortage gap?
Additional Explanation
or Reference
(OPTIONAL)
Penalty,
Charge, or
Other
Enforcement?
For Retail
Suppliers Only
Drop Down List
Volume or
Percentage
Drop down
Shortage
Gap
Reduction
Value
(May be a
range)
corrected. It shall be
presumed that a period
of twenty-four (24)
hours after the customer
discovers such break,
leak or malfunction, or
receives notice from the
City, is a reasonable time
within which to correct
such condition or to
make arrangements for
correction. If the leak,
break or malfunction is
discovered on a Sunday
or legal holiday, then it is
presumed that the
twenty-four (24) hour
period would begin at
12:00 midnight at the
end of the Sunday or
legal holiday.
1 Other - Require
automatic shutoff hoses Volume
Supports
other
demand
reduction
actions
The use of water for
washing vehicles or
boats, and cleaning
buildings or mobile
home exteriors, except
when using a shut-off
nozzle on the hose.

No

ATTACHMENT C
Item 8.2
Mountain House                                               Page 459 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
15 Submittal Table 8-3 Retail: Demand Reduction Actions Water Code Section 10632(a)(4)(B) and (E)
Yes Is the Supplier completing this table using the standard six levels? (yes/no) Shortage
Level
Demand
Reduction
Actions
Drop down list
These are the
only categories
that will be
accepted by the
WUEdata online
submittal tool.

Select those that
apply.

How much is this going to
reduce the shortage gap?
Additional Explanation
or Reference
(OPTIONAL)
Penalty,
Charge, or
Other
Enforcement?
For Retail
Suppliers Only
Drop Down List
Volume or
Percentage
Drop down
Shortage
Gap
Reduction
Value
(May be a
range)
1 Other - Prohibit
vehicle washing
except at
facilities using
recycled or
recirculating
water
Volume
Supports
other
demand
reduction
actions
The operation of any
non-self-service
commercial car washes
unless the soap/water
for such use is reclaimed.

No
1 CII -
Restaurants
may only serve
water upon
request
Volume
Supports
other
demand
reduction
actions
Provide water to patrons
in restaurants except
when specifically
requested by the
patrons.

No
1 Water Features
- Restrict water
use for
decorative
water features,
such as
fountains
Volume
Supports
other
demand
reduction
actions
Use of water in publicly
displayed ornamental
fountains in public or
commercial
establishments, except
when specifically
approved by the City.

No
1 Other - Prohibit
use of potable
water for
washing hard
surfaces
Volume
Supports
other
demand
reduction
actions
Use of water to wash
driveways, sidewalks,
patios, parking lots,
aprons and other similar
exterior surfaces, except
for sanitation, public
health and safety, and
fire protection purposes.

No

ATTACHMENT C
Item 8.2
Mountain House                                               Page 460 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
16 Submittal Table 8-3 Retail: Demand Reduction Actions Water Code Section 10632(a)(4)(B) and (E)
Yes Is the Supplier completing this table using the standard six levels? (yes/no) Shortage
Level
Demand
Reduction
Actions
Drop down list
These are the
only categories
that will be
accepted by the
WUEdata online
submittal tool.

Select those that
apply.

How much is this going to
reduce the shortage gap?
Additional Explanation
or Reference
(OPTIONAL)
Penalty,
Charge, or
Other
Enforcement?
For Retail
Suppliers Only
Drop Down List
Volume or
Percentage
Drop down
Shortage
Gap
Reduction
Value
(May be a
range)
1 Other Volume
Supports
other
demand
reduction
actions
The indiscriminate
running of water or
washing with water not
otherwise prohibited
above which is wasteful
and without reasonable
purpose and which is
evidenced by the runoff
of water from the
property or into
drainage facilities for
more than ten (10)
minutes.

No
1 Other Volume
Supports
other
demand
reduction
actions
Obtain water from a fire
hydrant, except for
construction purposes
and other purposes
specifically authorized by
the City Manager.

No
1 Other - Prohibit
use of potable
water for
construction
and dust
control
Volume
Supports
other
demand
reduction
actions
Use of water for dust
control purposes except
for recycled, reclaimed
or other non-potable
water, except for health
or safety purposes.

No

ATTACHMENT C
Item 8.2
Mountain House                                               Page 461 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
17 Submittal Table 8-3 Retail: Demand Reduction Actions Water Code Section 10632(a)(4)(B) and (E)
Yes Is the Supplier completing this table using the standard six levels? (yes/no) Shortage
Level
Demand
Reduction
Actions
Drop down list
These are the
only categories
that will be
accepted by the
WUEdata online
submittal tool.

Select those that
apply.

How much is this going to
reduce the shortage gap?
Additional Explanation
or Reference
(OPTIONAL)
Penalty,
Charge, or
Other
Enforcement?
For Retail
Suppliers Only
Drop Down List
Volume or
Percentage
Drop down
Shortage
Gap
Reduction
Value
(May be a
range)
2 Other Volume
Supports
other
demand
reduction
actions

Any use of potable water
from any fire hydrant is
prohibited, except by
regularly constituted fire
protection agencies for
fire suppression
purposes or by the City,
when alternate water
sources or recycled
water sources are
available. The decision as
to the availability of
alternate water sources
shall be that of the City.

In the absence of
alternate water sources
or reclaimed water
sources, use of potable
water from a hydrant
may be used provided a
permit for such use is
approved by the City.

Yes
2 Landscape -
Limit landscape
irrigation to
specific times
Volume
Supports
other
demand
reduction
actions
Irrigation of all exterior
landscaping including,
but not limited to, turf
areas, open ground,
crops, trees, grass, lawn,
ground cover, shrubbery,
or decorative plantings
using an irrigation
Yes

ATTACHMENT C
Item 8.2
Mountain House                                               Page 462 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
18 Submittal Table 8-3 Retail: Demand Reduction Actions Water Code Section 10632(a)(4)(B) and (E)
Yes Is the Supplier completing this table using the standard six levels? (yes/no) Shortage
Level
Demand
Reduction
Actions
Drop down list
These are the
only categories
that will be
accepted by the
WUEdata online
submittal tool.

Select those that
apply.

How much is this going to
reduce the shortage gap?
Additional Explanation
or Reference
(OPTIONAL)
Penalty,
Charge, or
Other
Enforcement?
For Retail
Suppliers Only
Drop Down List
Volume or
Percentage
Drop down
Shortage
Gap
Reduction
Value
(May be a
range)
system, hose, or outdoor
potable water faucet
shall be allowed only
between the hours of
9:00 p.m. and 6:00 a.m.
2 Landscape -
Limit landscape
irrigation to
specific days
Volume 22 gpcd
Irrigation of all exterior
landscaping including,
but not limited to, turf
areas, open ground,
crops, trees, grass, lawn,
ground cover, shrubbery,
or decorative plantings
using an irrigation
system, hose, or outdoor
potable water faucet
shall follow a 4-day
watering schedule and
be allowed on: (1)
Sundays, Mondays,
Wednesdays, and
Fridays for properties
with an odd-numbered
street address; and (2)
Sundays, Tuesdays,
Thursdays, and
Saturdays for properties
with an even-numbered
street address.

Yes

ATTACHMENT C
Item 8.2
Mountain House                                               Page 463 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
19 Submittal Table 8-3 Retail: Demand Reduction Actions Water Code Section 10632(a)(4)(B) and (E)
Yes Is the Supplier completing this table using the standard six levels? (yes/no) Shortage
Level
Demand
Reduction
Actions
Drop down list
These are the
only categories
that will be
accepted by the
WUEdata online
submittal tool.

Select those that
apply.

How much is this going to
reduce the shortage gap?
Additional Explanation
or Reference
(OPTIONAL)
Penalty,
Charge, or
Other
Enforcement?
For Retail
Suppliers Only
Drop Down List
Volume or
Percentage
Drop down
Shortage
Gap
Reduction
Value
(May be a
range)
2 Landscape -
Restrict or
prohibit runoff
from landscape
irrigation
Volume
Supports
other
demand
reduction
actions
Irrigation of exterior
landscaping, turf areas,
open ground, crops,
trees, grass, lawn,
ground cover, shrubbery,
or decorative plantings
in such a manner or
extent that allow water
to run off or escape from
the premises or to be
wasted.

Yes
3 Other Volume
Supports
other
demand
reduction
actions
All new requests for
potable water for
construction shall be
rejected by the City
unless it is determined
that the request, with
restrictions, will not
prevent the City from
meeting its water
conservation objectives.

Yes
3 Water Features
- Restrict water
use for
decorative
water features,
such as
fountains
Volume
Supports
other
demand
reduction
actions
Potable water to
ornamental fountains
shall be turned off.

Yes

ATTACHMENT C
Item 8.2
Mountain House                                               Page 464 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
20 Submittal Table 8-3 Retail: Demand Reduction Actions Water Code Section 10632(a)(4)(B) and (E)
Yes Is the Supplier completing this table using the standard six levels? (yes/no) Shortage
Level
Demand
Reduction
Actions
Drop down list
These are the
only categories
that will be
accepted by the
WUEdata online
submittal tool.

Select those that
apply.

How much is this going to
reduce the shortage gap?
Additional Explanation
or Reference
(OPTIONAL)
Penalty,
Charge, or
Other
Enforcement?
For Retail
Suppliers Only
Drop Down List
Volume or
Percentage
Drop down
Shortage
Gap
Reduction
Value
(May be a
range)
3 Landscape -
Limit landscape
irrigation to
specific days
Volume 22 gpcd
Irrigation of all exterior
landscaping including,
but not limited to, turf
areas, open ground,
crops, trees, grass, lawn,
ground cover, shrubbery,
or decorative plantings
using an irrigation
system, hose, or outdoor
potable water faucet
shall follow a 3-day
watering schedule and
be allowed on: (1)
Sundays, Wednesdays,
and Fridays for
properties with an oddnumbered street
address; and (2)
Tuesdays, Thursdays,
and Saturdays for
properties with an evennumbered street
address.

Yes
4 Water Features
- Restrict water
use for
decorative
water features,
such as
fountains
Volume
Supports
other
demand
reduction
actions
All potable water for
aesthetic water uses
shall be turned off.

Yes

ATTACHMENT C
Item 8.2
Mountain House                                               Page 465 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
21 Submittal Table 8-3 Retail: Demand Reduction Actions Water Code Section 10632(a)(4)(B) and (E)
Yes Is the Supplier completing this table using the standard six levels? (yes/no) Shortage
Level
Demand
Reduction
Actions
Drop down list
These are the
only categories
that will be
accepted by the
WUEdata online
submittal tool.

Select those that
apply.

How much is this going to
reduce the shortage gap?
Additional Explanation
or Reference
(OPTIONAL)
Penalty,
Charge, or
Other
Enforcement?
For Retail
Suppliers Only
Drop Down List
Volume or
Percentage
Drop down
Shortage
Gap
Reduction
Value
(May be a
range)
4 Other - Prohibit
use of potable
water for
construction
and dust
control
Volume
Supports
other
demand
reduction
actions
All existing potable
water use for
construction purposes
shall cease. All new
requests for potable
water for construction
shall be rejected by the
City.

Yes
4 Landscape -
Limit landscape
irrigation to
specific days
Volume 22 gpcd
Irrigation of all exterior
landscaping including,
but not limited to, turf
areas, open ground,
crops, trees, grass, lawn,
ground cover, shrubbery,
or decorative plantings
using an irrigation
system, hose, or outdoor
potable water faucet
shall follow a 2-day
watering schedule and
be allowed on: (1)
Wednesdays and
Sundays for properties
with an odd-numbered
street address; and (2)
Tuesdays and Saturdays
for properties with an
even-numbered street
address.

Yes

ATTACHMENT C
Item 8.2
Mountain House                                               Page 466 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
22 Submittal Table 8-3 Retail: Demand Reduction Actions Water Code Section 10632(a)(4)(B) and (E)
Yes Is the Supplier completing this table using the standard six levels? (yes/no) Shortage
Level
Demand
Reduction
Actions
Drop down list
These are the
only categories
that will be
accepted by the
WUEdata online
submittal tool.

Select those that
apply.

How much is this going to
reduce the shortage gap?
Additional Explanation
or Reference
(OPTIONAL)
Penalty,
Charge, or
Other
Enforcement?
For Retail
Suppliers Only
Drop Down List
Volume or
Percentage
Drop down
Shortage
Gap
Reduction
Value
(May be a
range)
5 Landscape -
Limit landscape
irrigation to
specific days
Volume 22 gpcd
Irrigation of all exterior
landscaping including,
but not limited to, turf
areas, open ground,
crops, trees, grass, lawn,
ground cover, shrubbery,
or decorative plantings
using an irrigation
system, hose, or outdoor
potable water faucet
shall follow a 1-day
watering schedule and
be allowed on: (1)
Sundays for properties
with an odd-numbered
street address; and (2)
Saturdays for properties
with an even-numbered
street address.

Yes
6 Landscape -
Limit landscape
irrigation to
specific days
Volume 22 gpcd All landscape irrigation
shall be prohibited. Yes
DWR NOTES: Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Submittal Table 2-3.

NOTES: Shortage Gap Reduction Value for each level is estimated as 10% of the 2020 target of 217 gallons per capita per day.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 467 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
23 5.3 Operational Changes
During a water shortage at any declared level, the City may implement operational measures to support effective implementation of this WSCP. Operational changes may include, but are not limited to:
• Hiring temporary staff
• Reassigning existing personnel
• Increasing staff overtime to support water shortage response activities.

Operational measures may support a range of functions, including conducting water waste patrols, implementing communication and public outreach protocols, responding to customer service inquiries, scheduling and conducting site assessments and consultations, processing incentive or rebate applications, and carrying out compliance monitoring and enforcement activities.

In addition, the City may implement operational adjustments intended to reduce non-essential water use, such as limiting routine water main flushing activities where operationally feasible and restricting potable water use for fire department training drills, consistent with public health and safety requirements.

Operational changes will be evaluated at each water shortage level to determine the appropriateness, timing, and duration of implementation, based on prevailing water supply conditions, operational needs, and system reliability considerations.

5.4 Additional Mandatory Prohibitions
The City does not have any additional mandatory prohibitions related to water usage at this time.

5.5 Emergency Response Plan
The water shortage levels described in Section 4 apply to both foreseeable and unforeseeable water supply shortage conditions, including catastrophic water supply emergencies.

The City maintains an Emergency Response Plan (ERP) to address catastrophic and unanticipated water supply disruptions. The ERP outlines response procedures for a range of unforeseen incidents, including but not limited to water supply contamination, seismic events, major infrastructure failures, and other emergencies that may disrupt water system operations.

The ERP identifies actions to be implemented in advance of, during, and following emergency events to support continuity of service, protect public health and safety, and facilitate system recovery. For security and operational reasons, the ERP is maintained as a confidential document and is not included as an appendix to this WSCP.

5.6 Seismic Risk Assessment and Mitigation Plan
Legal Requirements:

Water Code Section 10632.5
(a) In addition to the requirements of paragraph (3) of subdivision (a) 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.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 468 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
24 (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.

In compliance with California Water Code Section 10632.5(a), this WSCP includes a seismic risk assessment and mitigation plan that evaluates the vulnerability of the City’s water system facilities to seismic hazards. The assessment considers key system components such as water supply facilities, storage tanks, transmission and distribution pipelines, and control systems. Based on the relatively recent construction of much of the City’s infrastructure and the findings of the City’s 2021 Risk and Resilience Assessment (RRA), overall seismic vulnerability is considered low to moderate. Prepared in accordance with the America’s Water Infrastructure Act (AWIA), the RRA systematically evaluated the City’s assets, threats, and risks to reduce overall system risk. The City will continue to reduce seismic risk through applicable design standards, emergency response planning, and future system improvements.

The Mountain House community was included in the San Joaquin County’s 2023 Local Hazard Mitigation Plan (LHMP), adopted on April 18, 2023. The LHMP was submitted to the Federal Emergency Management Agency (FEMA) and found to be in conformance with Title 44 Code of Federal Regulations Part 201.6 Local Mitigation Plans. Refer to Appendix A for the LHMP.

5.7 Shortage Response Action Effectiveness
The effectiveness of the City’s shortage response actions will be evaluated through ongoing monitoring of water supply conditions, customer water use, and compliance with adopted water use restrictions.

Because water shortage conditions may result from a variety of foreseeable and unforeseeable circumstances, the effectiveness of individual response actions may vary depending on the severity, duration, timing, and cause of the shortage.

The City will use water production and customer water use data collected through its metered water system to compare actual water use against projected demands and the demand reduction targets associated with each declared water shortage level.

Certain shortage response actions are expected to result in measurable reductions in water demand.

Other actions, including public outreach, education, and communication efforts, support the overall effectiveness of the City’s water shortage response but may not be independently quantifiable. These supporting actions are nonetheless essential to promoting public awareness, encouraging voluntary conservation, and reinforcing mandatory requirements.

The City will evaluate the effectiveness of shortage response actions using multiple indicators, including, but not limited to:
• Progress toward achieving the demand reduction targets associated with the declared water shortage level;

ATTACHMENT C
Item 8.2
Mountain House                                               Page 469 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
25 • Trends in total system water use and water use by customer sector; • The number and nature of reported or observed water waste violations; • Customer compliance rates and enforcement outcomes; and • Input and feedback from City staff and the public.

If monitoring indicates that implemented shortage response actions are not sufficient to address the identified supply shortfall, the City may intensify existing actions, implement additional measures identified in this WSCP, or advance to a higher water shortage level, as appropriate. Conversely, if water supply conditions improve or demand reductions exceed targets, the City may modify or relax response actions while continuing to ensure water supply reliability.

The results of this evaluation will inform the City’s AWSDA, ongoing operational decision-making, and future refinements to the WSCP, consistent with the adaptive management approach described in Section

11. ATTACHMENT C
Item 8.2
Mountain House                                               Page 470 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
26 6 Communication Protocols
Legal Requirements:

Water Code Section 10632 (a)(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
In the event of a water shortage, the City will provide timely and effective communication to customers, the general public, interested parties, and relevant local, regional, and state agencies. Clear and consistent communication is essential to ensure appropriate response actions, public awareness, and regulatory coordination during both foreseeable and unforeseeable water shortage conditions.

This section describes the City’s communication protocols for anticipated water shortages identified through planning and assessment activities, as well as for unanticipated emergency events.

6.1 Communication for Foreseeable Events
Water shortage conditions may be foreseeable when identified through the AWSDA, as described in Section 3. When the potential for a water shortage is identified, the City Council may determine and declare a water shortage emergency in accordance with the City’s MMC. The City will need to update the MMC, Title 5, Division 3, to fully align with and implement the water shortage levels, demand reduction actions, and enforcement measures identified in this WSCP.

The City will hold a duly noticed public meeting to present the current or projected water shortage conditions identified through the AWSDA. At the public meeting, the City Council will determine whether a water shortage emergency exists, the severity of the shortage, and the applicable water shortage level.

The City Council will also consider the shortage response actions triggered or anticipated to be triggered by the declared shortage level and may take action to adopt a resolution declaring a water shortage emergency, establishing the applicable shortage level, and authorizing implementation of response actions.

For foreseeable water shortage events, the City may implement one or more of the following communication actions at any water shortage level, as appropriate:

1. Coordinate internally and with regional water service providers and San Joaquin County regarding the potential proclamation of a local emergency.

2. Issue public notice of City Council meetings at which AWSDA findings and recommendations related to water shortage conditions and response actions will be presented.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 471 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
27 3. Communicate water shortage conditions, response actions, and customer responsibilities through a combination of bill inserts, newsletters, the City website, social media, press releases, and blog posts.

4. Communicate with relevant local, regional, and state agencies and officials, primarily through email correspondence.

6.2 Communication for Unforeseeable Events
Water shortages may also result from unforeseeable events such as earthquakes, fires, infrastructure failures, civil unrest, or other catastrophic incidents. In these circumstances, communication protocols and procedures outlined in the City’s ERP will guide notification and public information activities.

Depending on the nature and severity of the event, the City may implement communication actions at any water shortage level.

Communications during unforeseeable events will generally follow the established chain of command. As described in the ERP, events that cause significant disruption to water supply may result in activation of the Technical Command Center (TCC), led by the TCC Commander. Notification and communication decisions will be made under the direction of the TCC Commander, who is responsible for reviewing and approving information prior to its release to the public or media.

Internal and external communications will be managed by the Communications/Media Coordinator, a role typically assigned to the Public Information Officer. Depending on the circumstances, the City may designate an alternate spokesperson to communicate with the media. The ERP also identifies key local, regional, and state contacts to be notified during emergency conditions.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 472 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
28 7 Compliance and Enforcement
Legal Requirements:

Water Code Section 10632 (a)(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.

This section describes the procedures the City will use to ensure compliance with, and enforcement of, the provisions of this WSCP. The City’s procedures include protocols for identifying violations, implementing enforcement actions of increasing severity for repeated or egregious noncompliance, and providing processes for appeal and exemption, as applicable.

7.1 Procedures
If a water shortage is anticipated, the City will implement the applicable WSCP actions and corresponding demand reduction measures identified for each shortage level. These actions may include increased public outreach, restrictions on outdoor water use, modified irrigation schedules, enforcement measures, and other conservation requirements as necessary to achieve the targeted reduction in water demand.

The City’s water system is metered system-wide, including at key facilities and at each customer connection. Water use data may be quantified and evaluated to determine the extent of customer compliance with applicable water use restrictions. The City may also identify potential noncompliance through public reports of water waste, the City’s online reporting tools, staff inspections, automated alerts from AMI, and automated or manual review of customer water use data.

Violations of the City’s water shortage emergency requirements shall be enforced in accordance with the City’s MMC, Title 5, Division 3, Chapter 2, including applicable provisions related to written warnings, flow restrictors, penalties, termination of service, and appeal procedures. § 5-3-203 VIOLATION OR FAILURE TO CORRECT VIOLATION OF WATER CONSERVATION REQUIREMENTS [1]
a) Whenever the City becomes aware of a customer violating, causing or permitting a violation of the provisions of the MMC, a written notice stating the nature of the violation shall be delivered to the customer at the premises by personal services or by first class mail and by posting in a conspicuous location at the premises. A copy of the notice shall be mailed to the customer who is regularly billed for use of water at the premises. All such notices also may be given to any other person known to the City who is responsible for the violation or the correction thereof, including a property owner of record where the owner rents the premises. The notice shall describe the nature of the violation and order that the violation be corrected, cured or abated immediately or within such specified period as the City believes is reasonable under the circumstances. The warning shall include a statement that upon a subsequent violation a flow restrictor may be installed on the water line to the premises.
b) Upon occurrence of a second violation or failure to immediately correct, cure or abate a violation, a second notice shall be served, as provided above. The notice shall: (1) order the immediate correction, cure or abatement of the violation, (2) state that a flow restrictor will be installed on the water line to the premises for at least forty-eight (48) hours' time period, and (3) impose a fine or a surcharge of fifty dollars ($50.00) to cover the cost of installing and removing the

ATTACHMENT C
Item 8.2
Mountain House                                               Page 473 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
29 restrictor. The fine shall be paid prior to removal of the restrictor. In the event that there is a third or subsequent violation for which notice is served as provided above, the City shall have the option to install a flow restrictor in the water line to the premises. The flow restrictor may not be removed by the City until fourteen (14) calendar days have elapsed from the date of installation and the fine, which is provided for in this section, has been paid. c) In the event that the flow restrictor installed by the City is bypassed or removed by other persons than the City, then the City may install a new flow restrictor on the water line to the premises. In addition, the City has the option to disconnect the service to the premises. Resident and owner of the premises will be jointly and severally responsible for the payment of fifty dollars ($50.00) per flow restrictor, which is installed by the City. Notice shall be given as set out under Subsection (a) of this section that an additional flow restrictor has been installed on the water line and that water to the premises will be disconnected. The decision for disconnection of water service may be appealed, within three (3) calendar days of service of the notice to the City Manager, or his designee. The appeal must contain information as to appellant's address for the purpose of service of the decision of the City Manager. Service of the decision shall be considered complete upon leaving a copy of the decision at the address supplied by appellant and mailing the same to the address.
(Ord. 2024-23, § 1(Exh. A), 2024)

7.2 Appeal Process
The City’s MMC, Title 5, Division 3, Chapter 3, establishes the appeal process available to the City customers subject to enforcement actions.
§ 5-3-308 APPEALS [1]
a) Procedure. Any customer may appeal for reconsideration of the City Manager's classification of use, allocation or determination of a request for an increase in allocation on the basis of hardship or incorrect calculation. Appeals for reconsideration shall be processed as set forth below.
1) Any customer appealing for reconsideration of the classification or allocation shall do so in writing to the City Manager by either using forms provided by the City or by letter setting forth in detail the reasons for the appeal. 2) The appeal for reconsideration shall be reviewed by the General Manager and a site visit scheduled if required.
3) If an appeal for reconsideration is sustained, a condition of approval may include a requirement for the installation of water efficient plumbing fixtures and/or irrigation systems.
4) The City Manager shall review all appeals for reconsideration and make decisions on the appeal.
5) If an applicant disagrees with the City Manager's decision, the decision may be appealed in the same procedural manner as specified in Subsection (a) of this section to the City Council. If an appeal to the City Council is requested, the customer shall be notified of a hearing date by mail. Such hearing shall be scheduled within thirty (30) days of filing the appeal. A decision shall be forwarded to the applicant within fifteen (15) days after completion of the hearing.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 474 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
30 b) Each appeal to the City Council shall be accompanied by the payment of an appeal fee in an amount set by resolution of the City Council from time to time to defray the costs of the appeal to the City.
(Ord. 2024-23, § 1(Exh. A), 2024)

ATTACHMENT C
Item 8.2
Mountain House                                               Page 475 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
31 8 Legal Authorities
Legal Requirements:

Water Code Section 10632 (a)(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. [see below] (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.

Water Code Section Division 1, Section 350
Declaration of water shortage emergency condition. The governing body of a distributor of a public water supply, whether publicly or privately owned and including a mutual water company, shall declare a water shortage emergency condition to prevail within the area served by such distributor whenever it finds and determines that the ordinary demands and requirements of water consumers cannot be satisfied without depleting the water supply of the distributor to the extent that there would be insufficient water for human consumption, sanitation, and fire protection.

The City’s MMC Title 5, Division 3, will need to be updated to provide the legal authority for the City to declare water shortage emergencies and implement water conservation and demand reduction measures consistent with the City’s WSCP.

Upon determination that a water shortage emergency exists, the City Council may, by resolution, declare a water shortage emergency and authorize implementation of the WSCP. A water shortage emergency declaration shall be based on findings made by the Council and shall remain in effect until the Council determines, by subsequent resolution, that the emergency condition has abated, changed in degree, or no longer exists.

When a water shortage emergency is identified, the City may coordinate interdepartmentally, with regional water service providers, and with San Joaquin County regarding the potential proclamation of a local emergency, in accordance with the California Emergency Services Act (California Government Code, Article 2, Section 8558).

In a duly noticed public meeting, the City Council will determine whether a water shortage emergency condition exists and, if so, the severity of the emergency and the water use regulations and restrictions necessary to respond to the shortage. Water shortage emergency declarations will be made in accordance with CWC Division 1, Chapter 3.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 476 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
32 CWC Division 1, Section 350 provides that:
“…The governing body of a distributor of a public water supply…shall declare a water shortage emergency condition to prevail within the area served by such distributor whenever it finds and determines that the ordinary demands and requirements of water consumers cannot be satisfied without depleting the water supply of the distributor to the extent that there would be insufficient water for human consumption, sanitation, and fire protection.”
Declaration of a water shortage emergency under this authority triggers implementation of the communication protocols described in Section 6 and the compliance and enforcement procedures described in Section 7 of this WSCP.

ATTACHMENT C
Item 8.2
Mountain House                                               Page 477 of 741 City of Mountain House
Water Shortage Contingency Plan
June 2026
33 9 Financial Consequences of WSCP
Legal Requirements:

Water Code Section 10632(a)(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).
(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. Due to the City billing customers in part based on the volume of water consumed, implementation of water shortage response actions may result in reduced water sales and associated revenue impacts. These revenue impacts may occur as customers reduce water use in response to water shortage conditions and associated demand reduction measures.

The City’s water rate structure is designed to minimize the financial impacts of reduced water use during water shortage conditions. A significant portion of water utility revenues is derived from fixed charges, including operation and maintenance components, which typically represent more than sixty percent of the average monthly water bill, exclusive of debt service charges. This structure helps stabilize revenues during periods of reduced water consumption.

The City periodically conducts water rate studies that evaluate system costs, customer growth, infrastructure needs, and the financial effects of conservation and demand management measures. These studies may include recommendations for rate stabilization mechanisms and drought contingency reserves to help mitigate the financial impacts associated with reduced water sales during water shortage conditions. Rate adjustments are implemented in accordance with applicable legal requirements, including Proposition 218, and through duly noticed public processes.

The current pricing structure is comprised of two components. The volumetric charge is based on hundred cubic feet of water use and has rates for two categories: residential and non-residential accounts. The second component of the pricing structure is the monthly service charge. This charge accounts for the cost of the meter, operation and maintenance, and other facility costs and is based on the meter size.

While implementation of the WSCP may result in short-term revenue reductions, the City will continue to manage its financial resources to ensure continued operation, maintenance, and reliability of the water system. Financial planning, reserve policies, and rate structures will be evaluated and adjusted as necessary to support long-term fiscal sustainability while responding effectively to water shortage conditions.

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34 If needed, the City may implement additional strategies to address decreased revenue from water sales.

These strategies may include use of financial reserves, deferring capital improvement projects, reducing current and future operation and maintenance expenses, and conducting a rate study.

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35 10 Monitoring and Reporting
Legal Requirements:

Water Code Section 10632(a)(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.

The City’s water system is fully metered, from water supply sources through individual customer connections. Metering data are used as primary tools for monitoring water use, assessing compliance with water shortage response actions, and supporting reporting requirements associated with this WSCP.

A substantial portion of the water system is equipped with AMI, with the remaining connections served by automated meter reading (AMR) technology. The City will continue to expand AMI deployment as feasible. AMI capabilities allow the City to monitor customer water use at a high temporal resolution, enabling timely assessment of demand reduction performance, identification of potential noncompliance, and targeted customer outreach during water shortage conditions.

Water use data will be evaluated regularly to determine whether demand reduction goals associated with declared water shortage levels are being achieved. If reduction targets are not met during implementation of the WSCP at any water shortage level, the City will notify the Council and recommend additional or more aggressive response actions, as appropriate.

Monitoring results may also be used to evaluate the effectiveness of WSCP measures and to identify opportunities for improvement. If revisions to the WSCP are determined to be necessary to better achieve demand reduction objectives or address changing conditions, the City will update the WSCP in accordance with the procedures described in Section 11 and make the revised plan available as described in Section

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36 11 WSCP Refinement Procedures
Legal Requirements:

Water Code Section 10632 (a)(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.

This WSCP is intended to function as an adaptive management document and may be refined as necessary to ensure that the City’s shortage response actions and mitigation strategies remain effective and achieve the intended outcomes. Based on monitoring activities described in Section 10, as well as compliance and enforcement results described in Section 7, the City may adjust response actions and revise this WSCP to address changing conditions, implementation challenges, or observed performance.

When revisions to the WSCP are proposed, the updated plan will undergo the adoption process described in Section 13, including consideration by the City Council and distribution to San Joaquin County, City customers, and the general public, as applicable.

Feedback from the City staff and the public is an important component of the WSCP refinement process.

The City will seek input from staff who regularly interact with customers and implement water shortage response actions to assess the practicality and effectiveness of existing measures and to identify potential improvements or new actions.

Customer water use data may be evaluated by customer sector or by individual account to assess the effectiveness of demand reduction measures and compliance trends. The City will track water use violations and may evaluate their frequency and characteristics to identify restrictions that may be difficult for customers to comply with, as well as demand reduction actions that are particularly effective.

The City will also seek input from customers and the general public through its website and during regularly scheduled City Council meetings to inform future refinements to the WSCP.

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37 12 Special Water Feature Distinction
Legal Requirements:

Water Code Section 10632 (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.

The City distinguishes special water features, such as decorative fountains and ponds, differently from pools and spas. Special water features are regulated separately. Regulations under the City’s MMC, Title 5, Division 3, Chapter 2, prohibit the use of potable water in publicly displayed ornamental fountains in public or commercial establishments unless specifically allowed by the City.

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38 13 Plan Adoption, Submittal and Availability
Legal Requirements:

Water Code Section 10632(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.

Water Code Section 10642
…Prior to adopting either [UWMP and WSCP], the urban water supplier shall make both the plan [UWMP] and water shortage contingency plan available for public inspection and shall hold a public hearing or hearings thereon…After the hearing or hearings, the plan [UWMP] or water shortage contingency plan shall be adopted as prepared or as modified after the hearing or hearings.

Water Code Section 10640
(b) …The supplier shall likewise periodically review the water shortage contingency plan as required by paragraph (10) of subdivision (a) of Section 10632 and any amendments or changes required as a result of that review shall be adopted pursuant to this article [Article 3 Sections 10640 -10645] Water Code Section 10644(a)(2)(b)
If an urban water supplier revises its water shortage contingency plan the supplier shall submit to the department a copy of it water shortage contingency plan prepared pursuant to subdivision (a) of Section 10632 [required elements of a WSCP] no later than 30 days after adoption, in accordance with protocols for submission and using electronic reporting tools developed by the department.

This WSCP is adopted concurrently with the City’s 2025 UWMP, by separate resolution. Prior to adoption, a duly noticed public hearing was conducted. A hard copy and electronic copy of this WSCP will be submitted to DWR within 30 days of adoption. Refer to Appendix B for public notices and outreach efforts.

No later than 30 days after adoption, copies of this WSCP will be available at the City’s offices. A copy will also be provided to San Joaquin County. An electronic copy of this WSCP will also be available for public review and download on the City’s website. A copy of the City resolution is included in Appendix C.

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39 14 References
[1] City of Mountain House Municipal Code, Title 5 – Health and Sanitation, Division 3 – Utilities, City of Mountain House, updated April 2, 2026.
https://library.municode.com/ca/city_of_mountain_house/codes/code_of_ordinances?nodeId= 15208

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A
Appendix A
San Joaquin County Local Hazard Mitigation Plan

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FEMA Region 9
1111 Broadway, Suite 1200
Oakland, CA 94607
www.fema.gov
April 18, 2023
Tiffany Heyer
Director of Emergency Operations
San Joaquin County – Office of Emergency Services
2101 E. Earhart Road, Suite 300
Stockton, CA 95206
Dear Tiffany Heyer:

The San Joaquin County Local Hazard Mitigation Plan 2023 was officially adopted by San Joaquin County on April 11, 2023 and submitted for review and approval to the Federal Emergency Management Agency (FEMA). The review is complete, and FEMA finds the plan to be in conformance with the Code of Federal Regulations, Title 44, Part 201, Section 6 (44 C.F.R. 201.6).

This plan approval ensures San Joaquin County’s continued eligibility for funding under FEMA’s Hazard Mitigation Assistance programs, including the Hazard Mitigation Grant Program (HMGP), the Building Resilient Infrastructure and Communities program (BRIC), and the Flood Mitigation Assistance (FMA) program. All requests for funding are evaluated individually according to eligibility and other program requirements. Approved hazard mitigation plans may also be eligible for points under the National Flood Insurance Program’s Community Rating System (CRS).

FEMA’s approval is for a period of five years, effective starting the date of this letter. Prior to April 18, 2028, San Joaquin County must review, revise, and submit their plan to FEMA for approval to maintain eligibility for grant funding. The enclosed plan review tool provides additional recommendations to incorporate into future plan updates.

If you have any questions regarding the planning or review processes, please contact the FEMA Region 9 Hazard Mitigation Planning Team at [email protected].

Sincerely,
for Kathryn Lipiecki
Director, Mitigation Division
FEMA Region 9

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BEFORE THE BOARD OF SUPERVISORS OF THE COUNTY OF SAN JOAQUIN

STATE OF CALIFORNIA

R E S O L U T I O N
R-23-54

ADOPTION AND APPROVAL OF THE SAN JOAQUIN COUNTY LOCAL HAZARD

MITIGATION PLAN
- - - - - - - - - - - - -
WHEREAS, San Joaquin County recognizes the threat that natural hazards pose to people and property within San Joaquin County; and,
WHEREAS, San Joaquin County has prepared a local multi-hazard mitigation plan, hereby known as San Joaquin County Local Hazard Mitigation Plan, in accordance with the Disaster Mitigation Act of 2000; and,
WHEREAS, the 2023 San Joaquin County Local Hazard Mitigation Plan identifies mitigation goals and actions to reduce or eliminate long-term risk to people and property in San Joaquin County from the impacts of future hazards and disasters; and, WHEREAS adoption by the San Joaquin County Board of Supervisors demonstrates their commitment to the hazard mitigation and achieving the goals outlined in the 2023 San Joaquin County Local Hazard Mitigation Plan.

NOW, THEREFORE, BE IT RESOLVED THIS BOARD OF SUPERVIOSRS DOES HEREBY adopt the 2023 San Joaquin County Local Hazard Mitigation Plan.

PASSED AND ADOPTED April 11, 2023 , by the following vote of the Board of Supervisors, to wit:

AYES: Canepa, Patti, Ding, Rickman
NOES: None
ABSENT: Villapudua
ABSTAIN: None

ROBERT RICKMAN
ATTEST: RACHÉL DeBORD Chairman, Board of Supervisors
Clerk of the Board of Supervisors County of San Joaquin County of San Joaquin State of California
State of California
By ___________________
Deputy Clerk

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CONTENTS
Introduction..........................................................................................................................4 2023 Local Hazard Mitigation Plan............................................................................... 4 Purpose ....................................................................................................................... 4 Plan Structure.............................................................................................................. 5 Community Profile................................................................................................................6 Floodplain Management Planning................................................................................ 7 The Planning Process..........................................................................................................8 Overview of the LHMP Process ................................................................................... 8

3.1.1 Opportunities for Stakeholders.............................................................................. 8

3.1.2 Plan Development Participants ............................................................................. 8

3.1.3 Contractors and Outside Assistance ....................................................................... 9

3.1.4 Planning Team Committee...................................................................................... 9 Public Involvement....................................................................................................... 9 Plan Preparation .........................................................................................................10

3.3.1 Draft Plan Review ................................................................................................10 Use of Existing Plans in the LHMP Process................................................................11

3.4.1 Review and Incorporation of existing plans, studies, reports, and technical information.........................................................................................................................11 Continued Public Involvement.....................................................................................11 Monitoring, evaluating, and updating the plan.............................................................11

3.6.1 Monitor and Evaluation ........................................................................................11 Hazard Identification ..........................................................................................................13 Hazard Identification ...................................................................................................13

4.1.1 Hazard Categories...............................................................................................13

4.1.2 Table of Previous Incidents..................................................................................16

4.1.3 Hazard Public Perception Survey Results............................................................20

4.1.4 Limitations ...........................................................................................................22 Risk Assessment ........................................................................................................22 Hazard Profile.............................................................................................................23

4.3.1 Flooding...............................................................................................................24

4.3.2 Dam Related Incidents.........................................................................................29

4.3.3 Drought................................................................................................................32

4.3.4 Wildfire.................................................................................................................35 Omission of Hazards...................................................................................................38 Severe or Repetitive Loss Properties..........................................................................38 Mitigation Strategy .............................................................................................................40 Existing Authorities, Policies, Programs and Resources .............................................40 National Flood Insurance Plan ....................................................................................41 Mitigation Goals ..........................................................................................................41 Mitigation Actions........................................................................................................41

5.4.1 Action #1- Howard Road......................................................................................41

5.4.2 Action #2- Kennefick Road...................................................................................42

5.4.3 Action #3- North Frontage Road ..........................................................................42

5.4.4 Action #4- Larch Road .........................................................................................42 Hazards Addressed: Flooding............................................................................................42

5.4.5 Action #5- Purdy Culvert Replacement ................................................................43

5.4.6 Action #8 - Corral Hollow Creek...........................................................................43

5.4.7 Action #7- San Joaquin County Climate Change Plan .........................................43

5.4.8 Action #12- Vegetation Management Coordination ..............................................43

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5.4.9 Action #13- Drought Awareness Campaign .........................................................44

5.4.10 Action #14- Dam Partnerships .............................................................................44 Action Plan for Prioritizing Mitigation Actions ..............................................................44 Integration of Local Hazard Mitigation Plan.................................................................47 Review, Evaluation and Maintenance ................................................................................48 Changes in Development............................................................................................48 Progress in Mitigation Efforts ......................................................................................48 Changes in Priorities...................................................................................................48 Plan Adoption ....................................................................................................................49 References ........................................................................................................................49 Appendices........................................................................................................................50 Planning Team............................................................................................................50 Table 1 Plan Revision Updates .................................................................................................12 Table 2- Previous Occurrences in San Joaquin County ............................................................16 Table 3- Hazard Perception Public Survey................................................................................21 Table 4- Hazard Profile Reference Table ..................................................................................24 Table 6- STAPLEE Process for Project Review ........................................................................45 Table 7- Implementation Strategy .............................................................................................46 Table 8- Mitigation Project Status .............................................................................................48 Figure 1- Impact-Probability Matrix- ..........................................................................................23 Figure 2- Cal OES My Hazards Map-........................................................................................27 Figure 3-National Inventory of Dams by Hazard Potential-........................................................30 Figure 5- U.S. Drought Monitor Time Series- ............................................................................34 Figure 6- Fire Hazard Severity Zones-. .....................................................................................36 Figure 7- Repetitive Loss Map- .................................................................................................39

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INTRODUCTION
As defined in Title 44 Code of Federal Regulations (CFR) Subpart M, Section 206.401, hazard mitigation is “any action taken to reduce or eliminate the long-term risk to human life and property from natural hazards.” As such, hazard mitigation is any work to minimize the impacts of any hazard event before it occurs. Hazard mitigation aims to reduce losses from future disasters. It is a process that identifies and profiles hazards, analyzes the people and facilities at risk, and develops mitigation actions to reduce or eliminate hazard risk. Implementing the mitigation actions—which include short- and long-term strategies that may involve planning, policy changes, programs, projects, and other activities—is the result of this process.

Over the past two decades, the Disaster Mitigation Act of 2000, known as (DMA 2000,) federal law, has driven local hazard mitigation planning. On October 30, 2000, Congress passed the DMA 2000 (Public Law 106-390), amending the Robert T. Stafford Disaster Relief and Emergency Assistance Act of 1988 (Title 42 of the United States Code Section 5121 et seq.) and repealing the act’s previous mitigation planning section (409) and replacing it with a new mitigation planning section (322). This new section emphasized the need for state, tribal, and local entities to coordinate mitigation planning and implementation efforts closely. This new section also provided the legal basis for the Federal Emergency Management Agency’s (FEMA) mitigation plan requirements for the Hazard Mitigation Assistance grant programs. 2023 LOCAL HAZARD MITIGATION PLAN
The goal of the planning process is to assess hazards and develop prioritized action plans to reduce risks in San Joaquin County. The updated information represents progress since 2018 and presents planned hazard mitigation work for the next five years. The plan's intended scope meets the Federal Disaster Mitigation Act requirement of 2000 (Public Law 106-390). The 2023 LHMP is organized according to the FEMA Local Hazard Mitigation Plan Handbook and was revised to reflect the system upgrades, improvements, and mitigations the County has completed since 2018. The 2023 LHMP will be submitted to the California Governor's Office of Emergency Services (Cal OES) for review by January 2023 before FEMA approval. The County team will promptly address comments and incorporate requested edits to keep within the Cal OES review schedule. Once the Cal OES review of the 2023 LHMP is complete, the County team will send the plan to FEMA for an assessment and approval period. In response to any FEMA comments, the County team will assign tasks to staff members to incorporate requested edits for the resubmittal of the final plan for FEMA approval.

PURPOSE
The Local Hazard Mitigation Plan intends to provide strategies for the County and other local jurisdictions to identify and implement mitigation actions for reducing damages from various natural and technological disasters. This Local Hazard Mitigation Plan should develop an ongoing process for mitigating damage before and after a disaster. Revisions of the General Plan(s) will include new suggestions and planning guidance for hazard mitigation goals, objectives, actions, and implementation strategies.

The 2023 LHMP outlines a process for assessing and analyzing those hazards to which San Joaquin County is most vulnerable. The process can improve the County’s resilience by performing a hazard risk assessment, using available tools to complete a capabilities assessment, and then identifying mitigation actions for these hazards.

The 2023 LHMP analyzes the risk posed to people and property by natural hazards and considers mitigation actions that the County could implement before such events. The goal is to reduce the

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risk to life and safety and the risk of property damage and service disruption caused by these natural hazards.

Mitigation projects and programs identified in the 2023 LHMP may be given priority for funding and technical assistance by the State and Federal government. The projects most likely to receive financing mitigate more than one hazard and address risks of concern to more than one agency.

This 2023 LHMP establishes prioritized mitigation goals and adopts a five-year implementation timeline, which the County will seek to implement, subject to funding and resource limitations.

PLAN STRUCTURE
This primary document's goals, actions, and strategies are only for the County's unincorporated areas. Jurisdictions can develop a local hazard mitigation plan for their authority or participate in the County's program. The 2023 LHMP is organized to follow FEMA's Local Mitigation Plan Review Tool, which demonstrates how hazard mitigation plans meet the DMA 2000 regulations.

As such, the specific planning elements of this review tool are discussed in their appropriate plan sections.
 Section 2: Community Profile- Provides basic information on a broad range of factors and better understands the community's context. This information permits specific areas, issues, and linkages to be identified and analyzed.
 Section 3: Planning Process - Provides an overview of the 2017-2018 planning process.

It identifies planning team members and describes their involvement with the planning process. This section details stakeholder outreach, public involvement, and continued public involvement. It provides an overview of the existing plans and reports, details how the Planning Process incorporates those documents into the 2023 LHMP, and provides a plan update method and schedule.
 Section 4: Hazard Identification and Risk Assessment - Identifies hazards affecting the Operational Area and profiles each risk with a list of past occurrences, threat analysis, and map or geographic description of the risk area.
 Section 5: Mitigation Strategy - Documents County mitigation goals, mitigation strategies by hazard type, and a list of projects that would mitigate sites of past or potential future damages.
 Section 6: Plan Update, Evaluation, and Maintenance - Procedures to maintain this ongoing plan. This element ensures that the County monitors the mitigation projects for modification, adds new projects, and completes mitigation actions.  Section 7: Plan Adoption - Documentation of plan adoption, including the County and other jurisdictions, level of participation, risk assessment, and mitigation actions.  Section 8: Appendices

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COMMUNITY PROFILE
San Joaquin County is located in the heart of the central San Joaquin Valley and has a population of approximately 685,300. The County has land use regulatory authority over all unincorporated land within the County, including all areas except land within the city limits of Escalon, Lathrop, Lodi, Manteca, Ripon, Stockton, Tracy, or land owned/managed by either the State or Federal governments (e.g., State Parks, National Parks, Bureau of Land Management areas, and tribal lands) and regions, not under County jurisdiction (e.g., public schools, prisons).

The County’s jurisdiction covers approximately 90 percent of all land, the vast majority of which is designated General Agriculture (A/G). However, there are more intensive residential and urban uses in the County’s surrounding cities and within unincorporated communities.

Significant population and employment growth are expected to occur within the County over the time frame of the General Plan (i.e., 2035) and will impact many aspects of the County, including agriculture, unincorporated communities, and employment opportunities. Shifting from historically inefficient development patterns in the Central Valley will require developers to increase the efficient use of existing infrastructure, reduce pollution and other modes of active transportation, and preserve agricultural and open space lands.

As the agricultural center of California, San Joaquin County’s farmland and agricultural heritage is preserved. Farms continue to produce a diverse array of high-quality agricultural produce and products. Both traditional and innovative farming practices flourish throughout the County.

Residents understand, appreciate, and are proud of the role agriculture plays in the history and economy of the County.

The County’s economy is diverse and robust in its global role as a source of food and agricultural commodities, a destination for tourists (The Delta, Agro-tourism, Wineries), and a supply of hightech and “green” manufactured products. Expanded educational opportunities and a highly interconnected shipping system provide a broad range of jobs across diverse industries, including those related to small, local businesses and new start-ups. Excellent schools and leadership programs prepare youth as the next generation of the County’s workforce.

San Joaquin County is linked to regional, state, and international destinations through an extensive network of roads, railways, waterways, and airports. Residents and businesses throughout the County are connected to the world through high-speed communications infrastructure. Communities are internally connected through an efficient and safe system of roadways, bridges, transit, bikeways, pedestrian trails, and sidewalks. County residents and farm equipment move together safely on well-managed and maintained roads.

Natural assets, such as air quality, the Delta, river corridors, and soils, are preserved, and residents know their importance. Aggregate resources supply the long-term development needs of the region and state. Energy efficiency and the use of alternative modes of transportation conserve energy resources, and new, sustainable energy resources are fully developed, providing clean and inexpensive energy.

The County values and protects its natural and cultural resources with expanded opportunities for residents and visitors to enjoy the County’s heritage and natural setting. Recreation opportunities, such as the Delta, waterways, and regional parks, are available and accessible to all County residents and visitors.

Agriculture, residents, and natural habitats are challenged to receive a continuous, cost-effective, and adequate clean water supply. The groundwater basin is challenged to sustain a state of equilibrium due to inconsistent precipitation throughout the region.

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The Delta is a “Place” of statewide significance and maintains its historical role in the County.

Delta channels convey water, which supports a thriving agriculture industry, diverse wildlife populations, world-class recreational opportunities, navigable boating routes, and the transportation of commercial goods. Fortified and well-maintained Delta levees provide safety and security to residents, patrons, infrastructure, and crops.

Communities and cities maintain their unique geographic identities, separated by agriculture and open space lands. Growth and development occur predominantly within and adjacent to existing communities and cities. A new expansion is carefully planned, including establishing community services and facilities in keeping with the existing community character.

Every community is desirable because of its range of housing choices, local job opportunities, access to services and shopping, great schools and parks, and sufficient infrastructure. Residents and businesses celebrate the rural heritage and small-town feel of their communities and the ethnic diversity of residents.

Finally, San Joaquin County is celebrated for the health and well-being of its residents. Residents and businesses proactively minimize their impacts on climate change and air quality. The County maintains plans and safeguards against potential hazards, such as flooding and wildland fires.

FLOODPLAIN MANAGEMENT PLANNING
The Community Rating System (CRS) is a voluntary incentive program that recognizes and encourages community floodplain management activities that exceed the minimum National Flood Insurance Program (NFIP) requirements. An additional indicator of floodplain management capability is the active participation of local jurisdictions in the CRS, adding extra local measures to protect from flooding. All 18 creditable CRS mitigation activities are assigned a range of point values. Communities can apply for an improved CRS class after accumulating points and reaching identified thresholds. Class ratings, ranging from 10 to 1, are tied to flood insurance premium reductions. As class ratings improve (decrease), the percent reduction in flood insurance premiums for NFIP policyholders in that community increases. Under CRS, discounted flood insurance premium rates reflect the reduction in flood risk. They result when community actions meet the three goals of CRS:
 Reducing flood damage to insurable property
 Strengthening and supporting the insurance aspects of the NFIP  Encouraging a comprehensive approach to floodplain management In 1993, San Joaquin County joined CRS and currently possesses a class 7 rating, entitling flood insurance policyholders to receive up to a 15% premium discount annually. The floodplain management planning activities for Unincorporated San Joaquin County are addressed throughout the 2023 LHMP.

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THE PLANNING PROCESS
The 2023 LHMP seeks to identify where San Joaquin County can take reasonable actions to minimize the adverse effects and dangers posed by disaster events before they occur. Despite the County’s efforts to reduce the potential for damage and harm while increasing readiness to respond to such circumstances, the potential for significant injury and damage arising from natural disasters remains.

OVERVIEW OF THE LHMP PROCESS

3.1.1 Opportunities for Stakeholders
The Office of Emergency Services works closely with the communities in its Operational Area, including the Special Districts in the County. The OES Staff sent a link to the existing 2018 LHMP plan, announced the beginning of the LHMP planning process, and requested a review and comments. OES sent an email to the identified Planning Teams members with a copy of the LHMP and asked them to review and provide updates on the current status of identified projects, or other pertinent information, to be reflected in the update.

Stakeholders were invited in writing (email) and during the OES Stakeholder meetings to participate in this LHMP project. Primary outreach efforts focused on County Departments, Special Districts, and neighboring communities. A list of planning team members is on the following page. The Senior Emergency Planner for OES was the project manager for this update.

All planning team members attended meetings (See Appendix A for agendas, sign-in sheets, and meeting dates) and provided input on the following:
 Types of hazards, their impacts, vulnerabilities, and previous occurrences  Reviewed a variety of plans, technical reports, and studies.  Developed mitigation goals
 Reviewed development trends
 Attended public meetings
The County Office of Emergency Services also held various planning meetings within the working group. The planning meetings accomplished several critical requirements, including defining general priorities, compiling and prioritizing hazard mitigation strategies, and determining the appropriate departments for implementing mitigation strategies.

3.1.2 Plan Development Participants
The Core Team comprises County departments, with the Office of Emergency Services as the Lead Agency, which has historically received disaster reimbursement and mitigation funds for measures impacted by a disaster and municipality stakeholders. The Core LHMP Planning Team was comprised of:
 San Joaquin County Department of Public Works:

Deputy Director Maintenance Superintendent
Channel Maintenance Superintendent
Management Analyst II
 San Joaquin County General Services/Parks & Recreation:

Park Administrator
 San Joaquin County Sheriff’s Office:

Lieutenant (Operations)
 San Joaquin County Office of Emergency Services:

Emergency Planning Team

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 California Office of Emergency Services:

Local Hazard Mitigation Planning Unit and Emergency Services Coordinator  City of Escalon:

Planning Team
 City of Lodi:

Planning Team
 City of Tracy:

Planning Team
 City of Stockton:

Planning Team
The Extended Planning Team was comprised of:
 Stockton Metropolitan Airport:

Airport Operations Supervisor
 San Joaquin County Community Development:
(GIS) Geographic Info Systems Program Management
 San Joaquin County Environmental Health:

Assistant Director
 San Joaquin County Public Health Services:

Public Health Emergency Preparation Coordinator
 San Joaquin County Agricultural Commissioner:

Deputy Agricultural Commissioner
 American Red Cross:

NGO – Coordinator
 County of San Joaquin Reclamation Districts:

Board Trustees / RD Engineers
 KSN Engineering:

Civil Engineering and Emergency Planning

3.1.3 Contractors and Outside Assistance
There were no additional contractors or assistance during this revision process.

3.1.4 Planning Team Committee
OES held a kick-off planning team meeting on October 18, 2022 and kept the planning team informed email. The kick-off meeting was conducted virtual via MS Teams. The sign-in sheets, team list, agendas, and other documentation from the planning sessions will be in Appendix A.

PUBLIC INVOLVEMENT
A draft copy of the 2023 LHMP was made available to the public. The review period gave the community two opportunities to comment on the draft 2023 LHMP.  The draft 2023 LHMP was published on the OES County website (https://www.sjgov.org/department/oes/local-hazard-mitigation-planning) for three weeks, starting on October 17, 2022. OES made changes based on public review comments and incorporated into the 2023 LHMP. The comments from the public can be found in Appendix B. The comments were used by the Planning Team in helping to determine the hazard priority and was instrumental in determining our High-Priority Hazards. We received many public comments on flooding and drought which is aligned with the goals outlined in the plan. We received many comments that do not meet the intent of this current LHMP, they will be addressed in the development and update of other County plans.

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 In addition to the three-week public review comment period, OES also provided an opportunity for public comments on the draft 2023 LHMP at a virtual and in person public town hall meeting on November 10, 2023. OES advertised the meeting and agenda items on the SJGov website, social media, and through email updates to staff and stakeholders.

No Public comments were received at these meetings to be incorporated into the 2023 LHMP.

PLAN PREPARATION
Revision to this LHMP followed the process of past revisions, but was expanded to include additional elements based on updated Federal review guide procedures and requirements. The San Joaquin County Hazard Mitigation Planning Committee’s process for this current revision followed these steps from October through December 2022:
 Contact standing LHMP (County department) committee members and request a review of the current Local Hazard Mitigation Plan for revision comments  Review the LHMP Review Guide for format and content requirements  Meet with staff to discuss and assign tasks
 Send participation requests to planning team members.  Update and revise LHMP
 Post ongoing drafts of the revised plan for review and comments  Implement an official “public comment” schedule to obtain additional feedback on hazard assessment, mitigation projects, and mitigation resources available  Submit for State and Federal approval
 Submit to the County Board of Supervisors for approval and adoption upon approval from Cal OES and FEMA
Ahead of a virtual kickoff meeting on October 18, 2022, OES staff reviewed and updated relevant information from the 2017 LHMP. All planning team members were identified and sent a copy of the basic revised plan and invited to participate in the kickoff meeting. During the kickoff meeting, it was discussed that much of the review process would be conducted virtually. All members listed in Appendix A attended the virtual meeting.

Team members were given until October 28, 2022 to provide feedback and input on the draft LHMP. On October 24, 2022, OES published a survey to collect the Team and public’s input on the threat and probability of hazards within the County. This survey identified hazards perceived to cause risk to the community based solely on probability of occurring and NOT the severity of the hazard. The survey participants voted on a scale of least likely to highly likely for a hazard to pose a threat to the community. The Core Planning team utilized this data to complete a risk assessment and verify the priority hazards for the County.

The Core Team conducted outreach to partners to submit projects related to the priority hazards.

Project submissions were due to OES by November 4, 2022. By November 7, 2022, OES emailed the Planning Team to rank the new and existing projects utilizing the STAPLEE Method. The Core Planning Team also hosted two town halls on November 10, 2022, one virtual and one in person, with minimal attendance.

3.3.1 Draft Plan Review
As Sections of the plan were reviewed and updated, OES posted the project on the OES website for review and comment.

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USE OF EXISTING PLANS IN THE LHMP PROCESS

3.4.1 Review and Incorporation of existing plans, studies, reports, and technical information.

San Joaquin County OES maintains over 25 plans covering emergency operations, support, hazards, and functions for the Operational Area. Plans are reviewed on a triennial basis and can be reviewed explicitly after a significant incident or training.  Specific plans and programs are reviewed for inclusion in this update for planning consistency among documents. Relevant information from reviewed projects, studies, reports, and technical information incorporated into the mitigation plan includes:
 State Hazard Mitigation Plan – OES has examined the State Hazard Mitigation Plan for recent updates on statewide hazard events and data for consistency.  San Joaquin County’s 2017 Local Hazard Mitigation Plan - Reviewed so OES could update the Plan.
 General Plan December 2016 - Demographics and land use were cross-referenced for inclusion into this Plan as part of the overall community profile. Additionally, area vulnerabilities identified in Specific Plan Areas were included as part of the vulnerability and risk assessment for wildfire, landslide, and flood. OES enclosed The General and Specific Plans in the County’s capability assessment inventory  Emergency Operations Plan – Reviewing the 2022 EOP gathering information about the assessed natural hazards.
 THIRA – The THIRA was reviewed for Hazard Identification and Risk Assessments and updated in November 2016. OES incorporated Hazard maps from the THIRA into the LHMP.
 Emergency Preparedness Plans – Contains agriculture, Medical Health, and public health information.
 Flood and Dam Failure Plan – OES reviewed the Plan for consistency for use as a reference in the “flood” section of the LHMP.
 Dam and Reclamation District Emergency Action Plans – Were reviewed for content and Inundation Data to ensure consistency with Cal OES dam inundation data.

CONTINUED PUBLIC INVOLVEMENT
OES will utilize strategies which include public outreach and awareness campaigns to improve public understanding of and response to hazard.

A completed copy of the plan will be available on the San Joaquin County Office of Emergency Services website in an accessible format. The approved plan will be open for public review and comment. The project manager will publish annual questionnaires and/or surveys on Social Media to garner public feedback on the approved plan. The project manager will monitor the LHMP website and County’s social media accounts for input on any changes, updates requested, and to address comments regarding the 2023 LHMP, including mitigation action implementation and the 2028 LHMP kickoff.

MONITORING, EVALUATING, AND UPDATING THE PLAN
This section describes OES’s method to monitor, evaluate, and update the LHMP.

3.6.1 Monitor and Evaluation
This plan will be monitored and evaluated by a subset of the planning team, specifically the OES LHMP project manager. If updated, OES will conduct plan revisions per FEMA's "Local Hazard Mitigation Planning (LHMP) Handbook (March 2013). The plan will be submitted to the Board of

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Supervisors for approval and publically shared. OES will update every five years. The update process will begin at least one year before the five-year expiration date. By following this process, OES can:
 Make sure that the mitigation strategy is implemented under the plan.  Establish the basis for an ongoing mitigation program locally.  Ensure that long-term monitoring of hazards is a routine activity.  Integrate the principles of mitigation into the decisions of community officials. This is important because it provides a clear understanding of daily responsibilities and department roles.
 Maintain involvement and accountability for the program's progress.

The project manager will complete the Annual Review Tracker every January and after any major disaster to ensure that the 2023 LHMP is relevant and effective in achieving the plan’s goals, focuses on increasing public awareness, and assists with curtailing the number of structures in hazardous locations. FEMA-funded mitigation projects will continue to be tracked and reviewed using FEMA Mitigation Progress Report forms; OES will include progress summaries in the Annual Review Tracker (Table A) at the beginning of each year.

Pending grant / funding approval (early 2023) the County will begin the process of writing a comprehensive Multi-Jurisdictional Hazard Mitigation Plan.

Table 1 Plan Revision Updates
Year Disasters Mitigation
Actions
New Studies/
Reports
Public
Outreach
Changes
made to LHMP
2023
2024
2025
2026
2027

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HAZARD IDENTIFICATION

HAZARD IDENTIFICATION
Hazard identification describes the nature of the hazard, disaster history, location, extent/severity, and probability of future events. According to the Comprehensive Preparedness Guide, 201:

Threat and Hazard Identification and Risk Assessment Guide, 2d ed. (CPG 201), dam failure, drought, earthquake, flood, landslide, tsunami, and wildfire are classified as natural hazards. CPG 201 does not classify climate change, outbreak/epidemic/pandemic, or public safety power shutoff. Therefore, the dangers profiled for this LHMP are discussed in alphabetical order and not by CPG 201 classification. The order does not signify the level of risk.

4.1.1 Hazard Categories
Using the following terminology organizes known hazards into local, state, and federal “commonly recognized” categories, especially weather-related threats. Commonly recognized types allow more accessible research into past events and smoother discussions with other jurisdictions and agencies.

Air Pollution: Caused by releasing gases, chemicals, foul odors, or physical materials suspended in the atmosphere. These materials can cause adverse health effects due to the toxicity of the chemical itself or by particulates causing physical distress on the respiratory system.

Chemical air pollution includes
 air releases from a hazardous materials spill,
 industrial emissions, or
 Air inversions are trapping vehicle emissions.

Physical material air pollution includes smoke from fires and dust storms. Foul odors can be created by excess or uncontrolled sewage or garbage.

Animal Pests: In San Joaquin County, birds and small mammals damage or consume agricultural products. Insects in all stages can damage crops by consumption or using crops for larvae production. Small mammals such as ground squirrels and birds can cause damage to fruit and nut-producing crops. Animal pests also include burrowing mammals such as gophers, moles, or beavers that can weaken levee structures by their activity.

Animal Diseases: Diseases carried by or that have infected other organisms. Diseases can move from one species to another (zoonotic) or be unique only to one species (vector).

Civil Disturbance: A general term used to describe some form of disturbance caused by a group.

It is usually a protest against political organizations or policies, economic concerns, or even the results of a sports contest. Examples range from passive resistance and sit-ins to riots, acts of sabotage, and all-out civil chaos.

Dam Failure: An event where the dam or part of the dam itself fails, or water otherwise overtops the barrier without the dam failing. Considered “installations containing dangerous forces” under International Humanitarian Law, dam failure has a massive impact on people and the environment.

Dense Fog: During rainy seasons, additional moisture creates a fog that diminishes visibility and creates a hazard, especially for transportation. San Joaquin County is subject to periods of localized thick fog in the winter called Tule Fog. This dense fog creates a visibility hazard on roads, freeways, airports, and rail lines throughout the county.

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Drought: A period of deficiency of the needed water supply. In California, the deficit caused by a lack of precipitation can significantly impact agriculture, cause damage to soils (salt intrusion), and lead to public water use limitations.

Earthquake: A movement in the earth's crust that Seismologists can quantifiably measure by seismic waves. They are most commonly found on plate boundaries. Still, they can also be associated with volcanic activity and occur anywhere on the earth. Earthquakes range from small and profound sub-surface events to large-scale near-surface events that have catastrophic effects on artificial structures and natural topography.

Energy Shortages: Loss in the ability of the power grid or energy infrastructure to meet the current needs of a type of consumption. Impairment can include a drop in oil reserves leading to gasoline shortages, the disruption of an electrical power grid (transmission systems), or overloading the power grid due to excessive demand. Events and resources far beyond the boundaries of San Joaquin County can influence energy shortages.

Excessive Rain: A period of precipitation that can overcome the natural ability of the environment or fabricated structures to control the runoff. The deluge may lead to local or widespread flooding.

Excessive rain in areas outside the County, such as the Sierra Nevada Mountains and foothills, can still affect the County by having runoff through the river systems of the Central Valley and into the Delta.

Expansive Soils: Clay soils (present in San Joaquin County expand with the addition of water and contract when it dries out. The change in volume when in contact with buildings, roadways, underground utilities, or levees can cause severe damage.

Extreme Temperature - Cold: A period where winter temperature drops below the point where most of the population or agriculture can adequately deal with it. Extreme cold temperatures in San Joaquin County can adversely affect sensitive populations such as the elderly or homeless and seriously affect crops such as fruit trees.

Extreme Temperature - Heat: A span where the temperature rises quickly to a higher-thanaverage temperature and then drops (spike). A prolonged period of hot days beyond expectation.

For temperatures to be considered extreme, they must adversely impact human health or agriculture.

Flood: Occurs when water reaches and tops some height above a given benchmark point, posing a threat to life or property caused by rising or spilling water. The sources of the floodwaters can be diverse. In San Joaquin County, flooding can occur from excessive rain overloading the river and levee system, a dam failure, or a levee failure. Floods can be slow, such as rising. water in a river, or rapid such as a catastrophic flood caused by dam or levee failure. Flooding can create significant physical, economic, agricultural, and social harm to affected areas.

General Fire Threats: These are County fires that may spread beyond an initial dwelling or involve chemicals that pose a more significant threat than the fire itself. Examples include fires in intense wind environments moving through residential areas and fires at chemical storage and use facilities such as Port of Stockton.

Ground Contamination: The discharge of chemicals into the soil. Sources of ground contamination are underground storage tanks (often fuels), the application of pesticides, leachate from landfills, and the dumping of chemicals and other waste directly onto the soil. Contaminated soils damage water supplies, make land areas untenable for habitation or other human use and require expensive long-term remediation.

Hazardous Material Emergencies: Events where the release of dangerous material, substance, or waste threatens people, property, or the environment. A hazardous material emergency will

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require the response of specially trained personnel with the correct equipment to contain, control, and clean up the material involved.

High Winds: Wind that causes physical damage to structures, trees, or agriculture within the county. High winds can also pose a flying debris hazard to the public and interfere with transportation systems.

Landslide: The downslope movement of rock and soil over a surface that can no longer maintain stability (incompetence). Influenced by gravity, landslides can be exacerbated by water flow, earthquakes, erosion, and manufactured disruptions such as excavation and construction.

Land Subsidence: A lowering of the land surface in response to subsurface weathering, the collapse or slow settlement of underground mines, or the removal of subsurface fluids such as oil or water from an aquifer.

Levee Break: Like a dam, a break is where the levee can no longer control the water. Generally, when levees do break, they are under stress due to the significant retention of water between the levee banks. Water saturation (boils), overtopping and erosion, land subsidence, earthquake, burrowing animals, or general lack of maintenance cause levee breaks.

Noise Pollution: Unwanted and unpleasant human, animal, or machine-created sound that interferes with the activity or balance of human or animal life. Sources of noise pollution include transportation systems, motor vehicles, car alarms, emergency service sirens, office equipment, barking dogs, power tools, audio entertainment systems, loudspeakers, and noisy people.

Plant Pathogens: Diseases carried by organisms (vectors) or caused by environmental conditions. Organisms that cause plant diseases include fungi, viruses, protozoa, bacteria, and parasitic plants.

Plant Pests: Insect that destroys plant or crop through consumption or use of the plant as a receiver for larvae. San Joaquin County monitors plant pests closely. Abatement programs are in place by the County Agricultural Commissioner’s office.

Public Health Emergency: An emergency declared by the county or the state public health officer of a health threat to the general populace of the county. Public Health Emergency could be a pandemic such as COVID-19, H1N1 flu, West Nile Virus epidemic, or excessive temperatures.

Soil Erosion: The gradual surface soil loss or movement due to energy or friction created by gravity, water, or wind. Soil erosion can intensify when forceful and persistent winds act upon loose soil. Essentially, this can cause dust storms posing a significant adverse health effect, an environmental hazard, and an agricultural disaster.

Terrorism: Defined by the U. S. Department of Defense as “the unlawful use of, or threatened use of violence to inculcate fear, intended to coerce or intimidate governments or societies as to the pursuit of goals that are generally political, religious or ideological.” Tornadoes and Severe Thunderstorms: An associated period of severe weather that can cause catastrophic damage. Although relevant, they are uncommon in San Joaquin County.

Train Derailment: An accident on a railway in which a train leaves the rails resulting in damage, injury, and death. Broken or misaligned rails, excessive speed, faults in the train and its wheels, and collisions can cause derailment with obstructions on the track. Derailment can also be a secondary effect in the aftermath of a collision between two or more trains. The most significant derailment hazard is when a freight train with cars of LNG or LPG is involved. Derailed LNG and LPG cars involved in a fire with the right circumstances create a catastrophic explosion and fire called a BLEVE (Boiling Liquid Expanding Vapor Explosion).

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Water Pollution: A material that harms a water body. The most common type of water pollution is a discharge of oil. However, almost any liquid or solid may be a water pollutant. Water pollution can adversely affect the biomass of an impacted area, damage water supply sources, injure those who come into contact, and create significant economic harm.

Weapons of Mass Destruction (WMD): Weapons designed to kill or injure large numbers of people and damage the physical infrastructure. Weapons of Mass Destruction may also cause environmental harm that would adversely affect people. WMDs also include nuclear, biological, radiological, and chemical (NBC) weapons.

Wildland Fires: Uncontrolled fires in rural areas and sparsely populated regions with limited vehicle access. A wildland fire is different from general fire threats by their sometimes-extensive size, the speed at which they can travel, and the ability to change direction and jump gaps. San Joaquin County is increasingly becoming a Wildland Urban Interface (WUI) zone. The WUI is the zone of transition between unoccupied land and human development. It is the line, area, or location where structures and other human development meet or intermingle with undeveloped wildland or vegetative fuels.

Winter Storms: Periods of intense weather can include low temperatures, heavy rain, snow or sleet, high winds, and icing conditions. The general climate in San Joaquin County is not known for severe weather conditions, but the potential is there for winter storms to occur.

4.1.2 Table of Previous Incidents
One method to identify hazards is to look at the events that have triggered federal and/or state disaster declarations that included San Joaquin County. Federal and state disaster declarations may be granted when the severity and magnitude of an event surpasses the ability of the local government to respond and recover. Disaster assistance is supplemental and sequential. When the local government’s capacity has been surpassed, a state disaster declaration may be issued, allowing for the provision of state assistance. Should the disaster be so severe that both the local and state governments’ capacities are exceeded, a federal emergency or disaster declaration may be issued allowing for the provision of federal assistance. In other words, a presidential disaster declaration puts federal recovery programs in place to help disaster victims, business, and public agencies. The federal government may issue a disaster declaration through FEMA, the U.S. Department of Agriculture (USDA), or the Small Business Administration (SBA). FEMA also issues emergency declarations, which are more limited in scope and without the long-term federal recovery programs of major disaster declarations (Farm Service Agency 2018). The quantity and types of damage are the determining factors.

Table 2- Previous Occurrences in San Joaquin County
Previous Occurrences – Earth Movement
Date: Location: Comments:
1881 Linden This quake possibly located on the Tracy-Stockton Fault had an estimated Modified Mercalli intensity of VII.
1906 Countywide The San Francisco earthquake of 1906, which caused historic destruction in the City, also caused strong
seismic shaking in San Joaquin County.
1940 Linden Two small quakes occurred with a Richter Magnitude of

4. It is not known if these earthquakes were connected to the Tracy-Stockton fault.
1979 Countywide - Seismic shaking with unverified impacts in the Delta 1980 Countywide - Seismic shaking with unverified impacts in the Delta. 1983 Countywide - Seismic shaking with unverified impacts in the Delta. 1983 Countywide - Seismic shaking with unverified impacts in the Delta.

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1984 Countywide -Seismic shaking with unverified impacts in the Delta. 1989 City of Tracy
Countywide
-Localized damages occurred within the City.
-Rolling seismic waves were felt throughout the County. 2006 Corral Hollow Rd -Heavy rains caused a landslide along Corral Hollow Road at a Lawrence Livermore Labs site.
2019 RD 2064 along Stanislaus
River
A large tree fell into the river causing the water to divert into the SJC side of the bank which led to erosion of a portion of the levee.

Previous Occurrences – Energy Shortage
1973-74 Countywide Middle East Oil Embargo
1978-83 Countywide Gasoline/Energy Shortage & Recession 1991 Countywide Iraq’s invasion of Kuwait resulting in U.S. military Action
2000 Countywide Statewide energy shortage causes rolling blackouts 2019 Out of County San Joaquin County communication systems are threatened during PSPS event in Calaveras Co.
2020 Countywide Public Safety Power Shut Offs during wildfire season 2022 Countywide Excessive heat event stressed the power grid and caused sporadic instances of power loss.

Previous Occurrences – Fire
2002 Contiguous counties to
Calaveras County
USDA Secretarial – winds, drought & fire
2002 Eligible contiguous County
business owners
SBA – physical and economic injury disaster
loans – Santana Row Fire – Santa Clara County
2020 Multiple locations
throughout Santa Clara
County, Alameda County,
Contra Costa County, San
Joaquin County, Merced
and Stanislaus County
SCU Complex Fire- 396,624 acres burned along the
Coastal Range from Merced County into San Joaquin
County.

Previous Occurrences – Floods
1980 Reclamation Districts: 2
Union West
38 Staten
524 Middle Roberts
544 Upper Roberts
548 Terminous
684 Lower Roberts
756 Bouldin
2023 Venice
2027 Mandeville
2028 Bacon
2029 Empire
2030 McDonald
2033 Brack
2037 Rindge
2039 Upper Jones
2040 Victoria
2041 Medford
2042 Bishop
2044 King
2072 Woodward
FEMA Declaration 3078, Public Assistance $604,400,
Individual Assistance $1,454,800 TOTAL: $2,059,200

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1980 Reclamation Districts:
2038 Lower Jones
2039 Upper Jones
FEMA Declaration 633, Public Assistance $2,730,329
Individual Assistance $8,077400 TOTAL: $10,807,729
1982 Countywide damages,
include: Reclamation
Districts:
2 Union West
38 Staten
348 New Hope
548 Terminous
684 Upper Roberts
756 Bouldin
2023 Venice
2027 Mandeville
2029 Empire
2030 McDonald
2033 Brack
2037 Rindge
2038 Lower Jones
2040 Victoria
2041 Medford
2044 King
2113 Fay
FEMA Declaration 651, Public Assistance $427,000
Individual Assistance $200,000 TOTAL: $627,000
1982 2030 McDonald FEMA Declaration 669, Public Assistance $4,642,500 Individual Assistance $5,245,789 TOTAL: $9,888,289
1982 Reclamation Districts: 2
Union West
38 Staten
348 New Hope
524 Middle Roberts
544 Upper Roberts
548 Terminous
684 Lower Roberts
756 Bouldin
773 Fabian
1007 Pico & Nagle 2023
Venice
2027 Mandeville
2028 Bacon
2029 Empire
2030 McDonald
2033 Brack
2037 Rindge
2038 Lower Jones
2039 Upper Jones
2040 Victoria
2041 Medford
2042 Bishop
2044 King
2058 Pescadero
2072 Woodward
2086 Canal Ranch
2089 Stark
FEMA Declaration 677, Public Assistance $ 23,455,600
Individual Assistance $ 3,224,510 TOTAL: $ 26,680,110

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2113 Fay
1986 Countywide, including:

Reclamation District: 348
New Hope
FEMA Declaration 758, Public Assistance $ 8,239,000
Individual Assistance $ 11,500,000 TOTAL: $19,739,000
1994 2027 Mandeville TOTAL: $750,000
1996 Countywide including:

Reclamation Districts:
2058 Pescadero
2062 Stewart
2064 River Junction
2075 McMullin
2095 Paradise
2096 Wetherbee Lake
2107 Mossdale
FEMA Declaration 1155, Public Assistance $ 14,725,364
Individual Assistance $ 84,937,350 TOTAL: $99,662714
1998 Countywide FEMA Declaration 1203, Public Assistance $ 1,437,000 Individual Assistance $ 1,666,000 TOTAL: $ 3,103,000
2004 Reclamation Districts:2038
Lower Jones
2039 Upper Jones
FEMA Declaration 1529, Public Assistance $ 42,488,326
Individual Assistance $44,977,071 TOTAL: $ 87,465,397
1995 Countywide State Proclamation
1997 Countywide State Proclamation
2006 Countywide State Proclamation
2017 Countywide (January & February Storms) Local Proclamation $1,683.659.19
2017 Countywide FEMA Declaration 4308 , $ unknown as of 9/2017 Previous Occurrences – Hazardous Materials
1998 Tracy Tracy Tire Fire
1989 Manteca Freight train derailment
2006 Stockton Freight train derailment
Annually Countywide Hazardous Materials - County agencies typically respond to more than 200 spills/incidents per year
Previous Occurrences – Train Derailment
1989 Mariposa Road Amtrak derailment 53 injured
Previous Occurrences – Public Health Emergencies
2009 San Joaquin County 11 Hospitalizations, 0 Deaths 7 2004 Countywide West Nile Virus – 3 human cases reported 2005 Countywide West Nile Virus – 36 human cases reported 2006 Countywide West Nile Virus – 8 human cases reported 2020-Current Countywide 2019 Novel Coronavirus (COVID-19) Pandemic 2022-Current Countywide 2022 Monkeypox Outbreak
Previous Occurrences – Drought
1977 Countywide Drought
1990 Countywide Drought
2002 Countywide Drought - USDA – Ag
2004 Countywide Drought with associated agricultural losses 2008 Countywide, Central
Valley Drought
Drought
2014 Statewide Drought (2014-2017)
2021 Statewide Drought (2020-current)

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Previous Occurrences – Weather : Extreme Temperature
2003 Countywide Extreme heat with agricultural and economic losses 2006 Countywide Extreme heat. At least 23 human deaths attributed to heat conditions, crop damages, loss of agricultural
productivity, and livestock fatality. Agricultural losses in production expected to continue into 2007.

Agricultural Losses up to $21,052,101
2013 Countywide Freeze Event
2016 Countywide Cold temperatures
2022 Countywide Extreme Heat event impacted a majority of the State.

Previous Occurrences – Weather : Severe Thunderstorms
1982 Countywide Excessive Rain – USDA Cost- $48,097,424 1990 Countywide Excessive Rain – Local Disaster – Cherries Cost - $35,000,000
1993 Countywide Excessive Rain – FEMA Cost - $10,250,000 1995 Countywide Storm - FEMA – Crop damage Cost - $6,020,000 1995 Countywide Storm - FEMA-1046-DR-CA
1995 Countywide Excessive Rain – Local Disaster - Cherry crop Damage Cost - $11,050,000
2002 Contiguous counties to
Calaveras County
Winds, drought & fire out of County – USDA
Secretarial - ag losses
2005 Countywide Hail and excessive rain
2006 Countywide Heavy winds & excessive rain
2021 Countywide October Atmospheric River created flooding issues as local pumps and storm drains were unable to keep
pace with the deposition of precipitation in the
County.
2022 Countywide Tornado touchdown 8 miles ESE of Isleton Previous Occurrences – Civil Disturbance
2020 Sporadic George Floyd Protests in various cities around the County.

Previous Occurrences – Terrorism
1989 Stockton Cleveland Elementary School Shooting,

4.1.3 Hazard Public Perception Survey Results
A survey was conducted with the core planning team, extended stakeholder team, and public.

This survey identified hazards perceived to cause risk to the community based solely on probability of occurring and NOT the severity of the hazard. The survey participants voted on a scale of least likely to highly likely for a hazard to pose a threat to the community. The ranking for the survey was based on the following:
 Highly Likely: Near 100% probability in next year
 Likely: Between 50 and 100% probability in next year, or at least one chance in 10 years  Neutral: Equal chances of occurring or not occurring
 Unlikely: Between 1 and 49% probability in next year or at least one chance in next 100 years
 Highly Unlikely: Less than 1% probability in next 100 years.

Survey results listed below are displayed based on the total number of votes received in each category. The votes indicate the perception of likelihood of each hazard occurring within the County.

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Table 3- Hazard Perception Public Survey
Hazard Descriptions Highly Likely Likely Neutral Unlikely Highly Unlikely Drought 97 39 20 4 7
Energy Shortage 72 58 27 4 6
Air Pollution 55 54 37 17 5
Public Health Emergency 65 37 35 16 14
Extreme Temperature - Heat 53 48 34 21 11
Water Pollution 48 49 30 29 11
General Fire Threats 41 47 41 28 10
Civil Disturbance 44 42 51 17 14
Levee Break 42 44 42 20 19
Terrorism 44 40 43 29 11
Wildland Fires 43 41 47 21 15
Dense Fog 36 47 37 33 15
Flood 29 51 43 24 20
Ground Contamination 31 47 49 26 14
Earthquake 27 45 50 32 13
Weapons of Mass Destruction (WMD) 42 30 31 34 30
Dam Failure 29 35 43 31 29
Hazardous Material Emergencies 25 39 51 37 14
Animal Pests 19 38 55 38 18
High Winds 18 37 58 34 20
Noise Pollution 19 33 43 48 24
Plant Pests 10 38 60 37 22
Excessive Rain 15 31 49 38 34
Animal Diseases 14 27 54 40 30
Extreme Temperature - Cold 11 25 41 50 39
Expansive Soils 15 20 56 41 35
Plant Pathogens 11 23 53 42 38
Winter Storms 11 22 39 53 42
Soil Erosion 8 20 58 47 34
Tornados and Severe Thunderstorms 6 22 39 52 48
Land Subsidence 9 14 32 50 62
Train Derailment 11 12 33 57 54
Landslide 5 15 28 57 61

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4.1.4 Limitations
Loss estimates, exposure assessments, and hazard-specific vulnerability evaluations rely on the best available data and methodologies. Uncertainties are inherent in any loss estimation methodology and arise in part from incomplete scientific knowledge concerning natural hazards and their effects on the built environment. Uncertainties also result from the following:
 Approximations and simplifications necessary to conduct a study  Incomplete or outdated inventory, demographic or economic parameter data  The unique nature, geographic extent, and severity of each hazard  Mitigation measures already employed
 The amount of advance notice residents have to prepare for a specific hazard event  The uncertain spatial accuracy of the dam inundation area data.  Lack of a standardized model for assessing sea level rise impacts. Multiple models provide multiple results. Not all models were run in the development of the sea level rise analysis.

These factors can affect loss estimates by a factor of two or more. Therefore, potential exposure and loss estimates are approximate and should be used only to understand relative risk. Over the long term, the planning partners will collect additional data to assist in estimating potential losses associated with other hazards.

RISK ASSESSMENT
Risk to natural hazards is a combination of hazard, vulnerability and capability. This section of the LHMP looks at both hazards and vulnerability. The risk assessment process identifies and profiles relevant hazards and assesses the exposure to lives, property and infrastructure to these hazards. The goal of the risk assessment is to estimate the potential losses in San Joaquin County from a hazard event.

This process also allows communities in the County to better understand their potential risk to natural hazards and provides a framework for developing and prioritizing mitigation actions to reduce the risks from future hazard events. The risk assessment process identifies and profiles relevant hazards and assesses the exposure of lives, property, and infrastructure to these hazards. The process allows for a better understanding of a jurisdiction’s potential risk to hazards and provides a framework for developing and prioritizing mitigation actions to reduce risk from future hazard events.

The Core Planning Team utilized the results of the public survey to assess and prioritize the highest priority hazards based on historical data and impact-probability matrices.

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Figure 1- Impact-Probability Matrix- Designed by the Core Planning Team to differentiate between the risk and impact of an incident and the likelihood of it occurring
The risk assessments in this plan describe the risks associated with each hazard of concern identified. Vulnerability of exposed structures and infrastructure was evaluated by interpreting the probability of occurrence of each event and assessing structures, facilities, and systems that are exposed to each hazard. Data used to support this assessment included the following:
• County GIS data
• Statewide and nationwide GIS datasets to support mitigation planning • California SHMP 2018
• San Joaquin County LHMP 2017
• Neighboring Jurisdictional HMPs
• FEMA and Dam Flood Inundation Mapping
• Written descriptions of inventory and risks provided by the jurisdictions • Online data sources
• Data and information from existing plans and studies
• Input from the team members
The planning team established the hazards listed below as being High-Priority for the jurisdiction.

These hazards were further profiled in the below subsection.

1. Flooding

2. Dam Related Incidents

3. Drought

4. Wildfire

HAZARD PROFILE
Overall hazard significance was based on a combination of information the Core Planning Team deemed to be relevant to the profile of the hazards. Each hazard profile was evaluated utilizing the following subcategories:
 Hazard/Problem Definition – This section gives a description of the hazard and associated issues followed by details on the hazard specific to the County Planning Area.  Geographic Area – This section gives a spatial description of the potential location or areas of the County where the hazard expected to impact.
 Extent (Magnitude/Severity) – This section gives a description of the potential strength or magnitude of the hazard as it pertains to the County. It describes how much damage could occur as a result of a hazard event.

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 Previous Occurrences – This section contains information on historical incidents, including impacts where known. Historical incident worksheets were used to capture information from participating jurisdictions on past occurrences.
 Probability of Future Occurrence – The frequency of past events is used in this section to gauge the likelihood of future occurrences. The likelihood of future occurrences is categorized into one of the following classifications:
 Vulnerabilities are summarized for all natural hazards. The vulnerability assessment addresses who or what is vulnerable to natural hazards or climate stressors, where someone or a critical facility is susceptible to damage, and when and why these assets may be vulnerable.

Table 4- Hazard Profile Reference Table
Geographic
Area
Probability of Future
Occurrence
Magnitude/Severity Significance/
Vulnerability
Extensive:
50-100% of
planning
area
Highly Likely: Near 100%
chance of occurrence in next
year or happens every year.

Catastrophic—More than 50 % of
property severely damaged; shutdown
of facilities for more than 30 days;
and/or multiple deaths
High:
widespread
potential
impact
Significant:
10-50% of
planning
area
Likely: Between 10 and 100%
chance of occurrence in next
year or has a recurrence
interval of 10 years or less.

Critical—25-50 % of property severely
damaged; shutdown of facilities for at
least two weeks; and/or injuries and/or
illnesses result in permanent disability
Medium:
moderate
potential
impact
Limited:

Less than
10% of
planning
area
Occasional: Between 1 and
10% chance of occurrence in
the next year or has a
recurrence interval of 11 to
100 years
Limited—10-25 % of property severely
damaged; shutdown of facilities for
more than a week; and/or
injuries/illnesses treatable do not result
in permanent disability
Low: minimal
potential
impact
Unlikely: Less than 1%
chance of occurrence in next
100 years or has a
recurrence interval of greater
than every 100 years.

Negligible—Less than 10 % of
property severely damaged, shutdown
of facilities and services for less than
24 hours; and/or injuries/illnesses
treatable with first aid

4.3.1 Flooding
Hazard Problem/Description: A flood is the temporary inundation of water or mud on normally dry land. Heavy or prolonged rain or dam collapse can cause inundation, as can flash floods.

Urban flooding occurs in developed areas where the amount of water generated from rainfall and runoff exceeds the storm water systems’ capacity. As land is converted from agricultural to urban uses, it often loses its ability to absorb rainfall. Rain flows over impervious surfaces such as concrete and asphalt and into nearby storm sewers and streams. This runoff can result in the rapid rise of floodwaters. During urban floods, streets can become inundated, and storm drains often back up because of the volume of water and become blocked by vegetative debris like yard waste, which can cause additional flooding. Development in or near the floodplain puts lives and property at risk. Flood damage can include structure inundation, erosion of stream banks, road embankments, foundations footings for bridges, impact damage from debris, and blockage of infrastructure, cropland destruction, and sewage releases from damaged tanks, and economic loss to agriculture.

Floods are among the most frequent and costly natural disasters in terms of human hardship and economic loss. Certain health hazards are common to flood events. Standing water and wet materials in structures can become breeding grounds for microorganisms such as bacteria, mold, and viruses. This can cause disease, trigger allergic reactions, and damage materials long after the flood. When floodwaters contain sewage or decaying animal carcasses, infectious disease

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becomes a concern. Direct impacts, such as drowning, can be limited with adequate warning and public education about what to do during floods. Where flooding occurs in populated areas, warning and evacuation will be of critical importance to reduce life and safety impacts.

Floodplains are defined as the areas immediately adjacent to a channel from a river, stream, or other waterway. Floodplains are illustrated on inundation maps, which show areas of potential flooding and water depths. In its common usage and based on FEMA guidelines, the floodplain most often refers to the area that is inundated by the 100-year flood, or the flood that has a one percent chance occurrence in any given year of being equaled or exceeded. The 1%-annualchance flood is the national minimum standard to which communities regulate their floodplains through the FEMA National Flood Insurance Program (NFIP). The 500-year flood is the flood that has a 0.2 percent chance of being equaled or exceeded in any given year. A 0.2%-annual-chance flood event would be slightly deeper and cover a greater area than a 1%-annual chance flood event. The potential for flooding can change and increase through various land use changes and changes to land surface, which may result in a change to the floodplain. A change in environment can create localized flooding problems inside and outside of natural floodplains by altering or confining natural drainage channels. These changes are most often created by human activity.

A levee is a raised area that runs along the banks of a river or canal. Levees reinforce the banks and help prevent flooding. By confining the flow, levees can also increase the speed of the water.

Levees can be natural or manmade. A natural levee is formed when sediment settles on the riverbank, raising the level of the land around the river. To construct a manmade levee, workers pile dirt or concrete along the riverbanks, creating an embankment. This embankment is flat at the top, and slopes at an angle down to the water. For added strength, sandbags are sometimes placed over dirt embankments. Levees provide strong flood protection, but they are not failsafe.

Levees are designed to protect against a specific flood level and could be overtopped during severe flood events.

Levees reduce, not eliminate, the risk to individuals and structure behind them. A levee system failure or overtopping can create severe flooding and high-water velocities. It is important to remember that no levee provides protection from events for which it was not designed, and proper operation and maintenance are necessary to reduce the probability of failure.

Geographic Area: Extensive All of San Joaquin County is subject to flooding of some level.

Areas of particular vulnerability to floods are around the Delta and waterways.

The County is located within the San Joaquin River watershed. The San Joaquin River is one of the longest rivers in Central California after the Sacramento River. The 366-mile long river starts in the Sierra Nevada and flows through the agricultural region of the Northern San Joaquin Valley, where it meets up with the Sacramento River at the Sacramento-San Joaquin Delta, a 1,000- sqaure mile system of channels and islands that drains more than 40 percent of the State’s lands.

It eventually flows through to Suisun Bay, San Francisco Bay, and the Pacific Ocean.

An important source of irrigation water as well as a wildlife corridor, the San Joaquin is among the most heavily dammed and diverted of California's rivers. Over the length of the San Joaquin River is fed by many other rivers and streams, and most notably the Stanislaus and Tuolumne rivers. Surface water from the San Joaquin River is also stored and diverted within the watershed.

Most of the surface water in the upper San Joaquin River is stored and diverted at Millerton Lakes Friant Dam near Fresno. In the central portion of the watershed, many agricultural and municipal users received water from irrigation districts, such as the Modesto, Merced, Oakdale, South San Joaquin, and Turlock Irrigation Districts.

Central Valley Flood Protection Plan (CVFPP): The physical risks associated with potential flooding and the regulatory requirements for floodplain management are important considerations

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when decisions are being made regarding future land use throughout the County. Those same risks guide the local and community-level emergency response needs. Economic growth and prosperity in the County are dependent upon federal, state, and local agency involvement on regional and local flood management systems. Flood protection regulations within California have been increased over the past few years through legislation. This legislation included the requirement for the California DWR and Central Valley Flood Protection Board (CVFPB) to prepare and adopt the CVFPP by 2012 and update every 5 years. The legislation also established certain flood protection requirements for local land use decision-making based on the CVFPP.

The law sets a higher standard for flood protection for the entire San Joaquin Valley. The standard was set for an urban level flood protection necessary to withstand a 1 in 200 chance of a flood event occurring in any given year (200-year flood) for areas developed or planned to have a population of at least 10,000. It also requires impacted counties to collaborate with cities to develop flood emergency response plans.

Magnitude/ Severity: Critical Flooding in San Joaquin impacts many areas, such as people, roads, buildings residential /commercial, parks/recreation areas, agriculture, and critical facilities.

Fiscal ramifications from flooding can happen due to road closures that affect businesses, Countyowned park closures, and airport closures. County staff working during a flood event can cause a financial burden on San Joaquin’s economy.

While there are some benefits associated with flooding, such as the replenishment of sediments and nutrients to agricultural lands, it is considered a hazard to development in floodplains. Floods can cause many cascading effects. Fire can break out as a result of dysfunctional electrical equipment. Hazardous materials can also get into floodways, causing health concerns and polluted water supplies. In many instances during a flood, the drinking water supply will be contaminated.

Flooding can have a major economic impact on the economy. Effects on the agriculture economy can be devastating, and a large amount of area at risk to flooding in the County is agricultural.

Flooding can damage crops and livestock. In addition to the obvious impacts on crops and animals, flooding can have deleterious effects on soil and the ability to reinvigorate the agricultural activities impacted once the flood waters recede. Damage to water resources such as underground irrigation systems, water storage reservoirs, springs and other natural water bodies could have a serious effect upon agriculture operations.

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Figure 2- Cal OES My Hazards Map- San Joaquin County as of October 2022 1 Previous Occurrences: Acampo Road and State Route 99, known as “Cooper’s Corner,” historically floods (approximately every ten years) during heavy rainfall. When this area floods, there is repeated damage to local elementary schools, residences, and businesses. There have been road closures and evacuations due to the flooding in this area.

The undercrossing at State Route 99 continues to flood due to vandalism and a poorly functioning backflow valve on the levee side of the Mokelumne River. Equipment failure has resulted in frequent flooding of the frontage road beneath the underpass. Frequent flooding causes damage to the roadway, and the inundation impacts the farms, businesses, and residences in this area.

Culverts located at Kennefick Road just north of Liberty Road have washed away during heavy rains. Damaged conduits destroyed over 100 feet of Kennefick Road, temporarily eliminating access to properties north of Liberty Road, which is the only access point for that area.

Howard Road Bridge, located over the San Joaquin River, suffered a slip-out failure on an uppermost portion of the northeast side of the eastern approach to the bridge. This failure is approximately 100 feet long by 40 feet wide, which has compromised the integrity of the roadway/bridge. Failure of the roadway in this area would limit access to critical portions of French

1 https://myhazards.caloes.ca.gov/

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Camp and Lathrop communities. The collapse will affect local businesses and residents traveling on this road/bridge.

Due to poor drainage and mix-use properties on the south side of West Larch Road, sheet runoff occurred going north into the County’s southern conveyance ditch located at the south side of West Larch Road. The runoff was over capacity for the current ditch, which was reduced due to encroachments and undersized driveway culvert crossings. Overflow from these issues resulted in the inundation of West Larch Road and properties (businesses/residences) in the drainage areas.

Continuous rains have caused the outer banks of the lake in the park to erode, affecting the park benches, picnic areas, and recreational equipment rental. Chrisman Road residential area continues to flood during heavy rainstorms, which causes homes to retain water in residential buildings due to flooding. The Purdy Culvert system located at the end of Partridge Road (a private road, non-county maintained) in Acampo, in a mixed residential and agricultural use area, needs to be replaced or upgraded due to flooding causing the site to overflow.

Probability of Future Events: The County is Highly-Likely to face a flood incident in the future.

Localized flooding such as a roadway or neighborhood is more probable than widespread flooding.

Due to the history of past flooding events and the natural drainage pattern of the County, flooding in San Joaquin County is likely to continue to occur. The potential for failure of one of the many levees throughout the County could create more risk for flooding. The 100-year flood is the flood that has a one percent chance in any given year of being equaled or exceeded. Based on past events, flooding events less severe than a 100-year flood and those outside of the 100-year floodplain occur frequently during periods of heavy rains.