retail and Wholesale Customers collectively. In the absence of a negotiated agreement, SFPUC has applied the Tier 1 split for a system-wide cutback up to 20%.
• Application of the Tier 2 Plan: The Tier 2 Drought Response Implementation Plan only applies during system-wide shortages of 20% or less. Because the "With Bay-Delta Plan" scenario results in wholesale cutbacks ranging from 31% to 48%, the Tier 2 Plan cannot be applied.
• BAWSCA Recommendation: In the absence of a negotiated approach for allocating RWS supply among the Wholesale Customers during shortages exceeding 20%, BAWSCA suggests that agencies apply these cutbacks equally across all agencies for their 2025 UWMPs.
• "Without Bay-Delta" Scenario: The SFPUC analyses do not anticipate any cutbacks during the required five-year drought sequence under the "Without Bay- Delta Plan" scenario.
Guidance for 2025 UWMP Reporting
For the 2020 UWMPs, most member agencies utilized the "With Bay-Delta Plan" scenario for their standard tables and included the "Without Bay-Delta Plan" scenario in supplemental tables or appendices. BAWSCA understands that the SFPUC intends to follow this same approach for its own 2025 UWMP.
Note on Future Modeling (HRL Program)
While the SFPUC previously indicated it would model the Tuolumne River Healthy Rivers and Landscapes Program (HRL), they have not provided that modeling at this time due to significant implementation uncertainties.
Enclosed: Attachment A – 2025 UWMP Supply Reliability Letter_2026-03-11 Attachment B – 2025 UWMP Wholesale Customer Dry Year Allocations
cc: Tom Smegal
Allison Schutte
Services of the San Francisco Public Utilities Commission
OUR MISSION: To provide our customers with high-quality, efficient, and reliable water, power and sewer services in a manner that values environmental and community interests and sustains the resources entrusted to our care.
525 Golden Gate Ave
San Francisco, CA 94102
(415) 554-3155
sfpuc.gov
March 11, 2026
Danielle McPherson
Senior Water Resources Specialist
Bay Area Water Supply and Conservation Agency
155 Bovet Road, Suite 650
San Mateo, CA 94402
Dear Ms. McPherson,
This letter contains the supply reliability of the San Francisco Public Utilities Commission (SFPUC) Regional Water System (RWS) that the SFPUC has prepared for the 2025 Urban Water Management Plan (UWMP), which the Wholesale Customers may also use in their respective 2025 UWMPs. The SFPUC has assessed the RWS’s supply reliability under the following planning scenarios:
1. Projected supply reliability for years 2030 through 2050, assuming total demand is equivalent to the sum of the projected retail and wholesale demands on the RWS, which includes Wholesale Customer purchase projections provided to the SFPUC by BAWSCA on March 4, 2026 (refer to Table 1 below).
2. Projected supply reliability for 2050, assuming total demand is equivalent to the sum of the projected retail demands on the RWS and the Wholesale Customers’ Supply Assurance of 184 MGD.
3. Under each of the above demand conditions, projected supply reliability for the following scenarios: (a) with implementation of the 2018 amendments to the Bay-Delta Water Quality Control Plan (Bay-Delta Plan Amendment) and (b) without implementation of the Bay-Delta Plan Amendment.
2025 UWMP Supply Reliability Memo
March 11, 2026
Table 1. Retail and Wholesale RWS Demand Assumptions Used for Supply Reliability Modeling (MGD)
20251 2030 2035 2040 2045 2050
Retail 61.1 62.7 61.2 61.9 64.0 66.7
Wholesale2 130.1 133.9 136.3 140.6 144.1 148.4
Total 191.2 196.6 197.5 202.5 208.1 215.1
1 2025 demands are from the FY 2024-25 Table J-1 water use calculations, prepared pursuant to the Water Supply Agreement between the SFPUC and the Wholesale Customers.
2 2030 through 2050 Wholesale Customer purchase projections were provided to the SFPUC by BAWSCA on March 4, 2026, and include demands for the cities of San Jose and Santa Clara.
The total amount of water the SFPUC can deliver to the Retail and Wholesale Customers from the RWS depends on several factors, including (1) the amount of water that is available to the SFPUC from natural runoff, (2) the amount of water in reservoir storage, and (3) the amount of water that the SFPUC releases from the RWS for purposes other than customer deliveries (e.g., instream flow releases below RWS reservoirs). For planning purposes, the SFPUC “average year” or “normal year” is based on historical hydrology under conditions that allow the RWS reservoirs to be filled over the course of the snowmelt season, allowing full deliveries to customers. For “dry-year” supply scenarios, the SFPUC plans its water deliveries using a water-supply planning methodology with reference to a simulated 8.5-year design drought.
In each demand scenario for 2030 through 2050, the SFPUC estimated RWS deliveries using the standard SFPUC procedure, which includes adding increased levels of rationing as needed in dry years to balance the demands on the RWS with available water supply. The five consecutive dry-year sequence shown in the tables below represent years 2 through 6 of the design drought.
The SFPUC chose this sequence because year 2 is the first year in which system-wide water use reductions could take effect, as the design drought sequence generally begins year 1 with full reservoirs. All simulations that the SFPUC has prepared for its 2025 UWMP have increased levels of rationing in the final years of the design drought sequence. The SFPUC has presented the results in the standardized format prescribed by DWR.
Assumptions about the status of the dry-year water supply projects included in the SFPUC’s Water System Improvement Program (WSIP) are provided below in Table 2 titled “WSIP Project Assumptions for RWS Supply Modeling.” The table reflects instream flow requirements at San Mateo and Alameda Creeks,
2025 UWMP Supply Reliability Memo
March 11, 2026
as described in the UWMP “common language” that the SFPUC provided to BAWSCA and the Wholesale Customers separately from this letter.
The SFPUC utilized the Water Shortage Allocation Plan (WSAP) that is incorporated in the Water Supply Agreement between the SFPUC and the Wholesale Customers to allocate the RWS supply available during dry years between the Retail Customers and the Wholesale Customers in the 2025 UWMP supply reliability analysis. The WSAP, also known as the Tier 1 Plan, defines the method for allocating between the Retail Customers collectively and Wholesale Customers collectively the available RWS supplies during system-wide shortages. The SFPUC and the Wholesale Customers most recently amended the WSAP in 2025. Also in 2025, the Wholesale Customers adopted an updated Tier 2 Plan, which allocates the collective Wholesale Customers’ share of available RWS supplies from the Tier 1 Plan among each of the 26 Wholesale Customers. The WSAP addresses shortages that require a system-wide reduction in water use of 20% or less, consistent with the SFPUC’s Level of Service Goal. For any shortage scenario requiring a system- wide reduction in water use above 20% in the supply reliability analysis, the SFPUC applied the Tier 1 Plan’s allocation of supplies between the Retail Customers and Wholesale Customers for a shortage requiring a system-wide reduction in water use of 16-20%.
Because of the uncertainty surrounding implementation of the Bay-Delta Plan Amendment, the RWS supply reliability assessment evaluates two future supply scenarios: (1) with implementation of the Bay-Delta Plan Amendment, and (2) without implementation of the Bay-Delta Plan Amendment. It is unknown when implementation may begin on the Bay-Delta Plan Amendment; for the purposes of the 2025 UWMP analysis, the SFPUC included it beginning in the 2030 modeling scenarios (see Tables 4a-4g and 6).
The SFPUC incorporated additional modeling assumptions in the 2025 UWMP analysis regarding the State Water Resources Control Board curtailments and assumptions regarding agreements with Turlock and Modesto Irrigation Districts pertaining to instream flow obligations.
1. During the last two drought periods, 2013-2016 and 2021-2023, the State Water Resources Control Board implemented curtailments through emergency regulations and curtailment orders that attempted to limit diversions from Central Valley watersheds including the Tuolumne River at certain times. Due to the uncertain legality of the State Water Resources Control Board’s curtailment actions as well as the
2025 UWMP Supply Reliability Memo
March 11, 2026
uncertainties regarding any potential future curtailment actions against San Francisco, the SFPUC’s RWS supply reliability analyses do not assume curtailments are in effect.
2. Through a 1966 agreement with the Modesto and Turlock Irrigation Districts (Districts), who are more senior downstream appropriative water rights holders on the Tuolumne River, San Francisco may become responsible for up to approximately 51.7% of any flow releases the Federal Energy Regulatory Commission (FERC) may require through issuance of a new license for the Districts’ Don Pedro Hydropower Project. The exact flow contribution for which San Francisco may become responsible is highly uncertain and may depend on multiple currently unknown factors, including an anticipated Endangered Species Act biological opinion from the National Marine Fisheries Service and a Clean Water Act section 401 water quality certification from the State Water Resources Control Board. San Francisco’s potential responsibility for FERC-ordered flows may further depend on San Francisco’s ability to enter into a new or extended agreement with the Districts to offset a portion of San Francisco’s flow contributions in exchange for payment. Due to the high levels of uncertainty surrounding the Districts’ FERC-relicensing process, as well as the unknown timing for license issuance, the SFPUC’s RWS water supply reliability analyses do not assume additional water supply losses from any potential new FERC-ordered flow releases.
3. The simulation of the Bay-Delta Plan Amendment scenario assumes that a 1996 agreement between San Francisco and the Districts (the Side Agreement), which allows San Francisco to pay the Districts in lieu of contributing a portion of current FERC-ordered flow releases, remains in effect, and that the San Francisco share of flows in excess of and not covered by the Side Agreement is approximately 51.7%. These assumptions were made for the purpose of completing the modeling for the UWMP update, and they do not represent a commitment by San Francisco or the Districts to any future agreement or of San Francisco accepting responsibility for any future FERC-ordered flow releases.
Based on current projected demands, supply modeling for the two future supply scenarios shows significantly different supply reliability projections for the RWS:
• With implementation of the Bay-Delta Plan Amendment: Under this scenario, using the demand assumptions shown in Table 1, RWS supplies are expected to range from full availability in an average year
2025 UWMP Supply Reliability Memo
March 11, 2026
(100%) to as low as 57% in multiple dry years when compared to water supplies in an average year. In other words, RWS supplies could be reduced by up to 43% in a multi-year drought. See Tables 4a-4g and 6. • W ithout implementation of the Bay-Delta Plan Amendment: Under this scenario, using demand assumptions shown in Table 1, there are no anticipated shortages of RWS supplies. See Tables 5a-5g and 7.
Tabl
e 8 below provides the Wholesale Customer purchase projections and Wholesale Customer allocation of RWS supply for the five-year drought risk assessment from 2026 to 2030. The supply projections for 2026 to 2030 are based on a linear growth from 2025 to 2030 levels of demand as calculated by BAWSCA. This table does not assume implementation of the Bay-Delta Plan Amendment because the start of implementation remains uncertain.
In the forthcoming 2025 UWMP, the SFPUC acknowledges that it has a Level of Service objective to meet an average annual water demand of 265 MGD from the SFPUC watersheds for Retail and Wholesale Customers during non- drought years, as well as a contractual obligation to supply 184 MGD to the Wholesale Customers, subject to reduction under certain conditions. The SFPUC will, accordingly, include the results of modeling based on a Wholesale Customer demand of 184 MGD to facilitate planning that supports meeting this Level of Service objective and its contractual obligations. The results of this modeling will be in an appendix to the 2025 UWMP prepared by the SFPUC.
The RWS supply projections shown in the tables below are more accurately characterized as supplies that will be used to meet projected Retail and Wholesale Customer demands.
It is our understanding that you will pass this information on to the Wholesale Customers. If you have any questions or need additional information, please do not hesitate to contact Jennifer Lee at [email protected] or (415) 551-4563.
Sincerely,
Steven R. Ritchie
Assistant General Manager, Water Enterprise
2025 UWMP Supply Reliability Memo
March 11, 2026
Table 2: WSIP Project Assumptions for RWS Supply Modeling Projects Base Year 2025 Base Year 2030 and
Beyond
Base Year 2040 and
Beyond
Lower Crystal Springs
Dam Improvements
Crystal Springs storage
not fully restored
Crystal Springs storage
not fully restored
Crystal Springs storage
not fully restored
Regional Groundwater
Storage and Recovery
(GSR) Project
GSR account partially
filled at spring 2020
level of 43,000 AF; GSR
recovery rate of
5.2 MGD
a
GSR account fully filled;
GSR recovery rate of
5.2 MGD
a
GSR account fully filled;
GSR recovery rate of
6.2 MGD
a
Alameda Creek
Recapture Project Project not built Project built and operating
Project built and
operating
Dry-Year Transfers Not in effect Not in effect Not in effect a. The GSR Project was intended to provide 7.2 MGD over 7.5 years, however current limitations on the number of wells available will result in deliveries less than 7.2 MGD over 7.5 years.
Table 3: Projected Total Regional Water System Supply Utilized and Portion of Regional Water System Supply Utilized by Wholesale Customers in Normal Years [For Table 6-9]:
RWS Supply 2030 2035 2040 2045 2050
RWS Supply Utilized (MGD) 196.6 197.5 202.5 208.1 215.1 RWS Supply Utilized by Wholesale
Customersa (MGD) 133.9 136.3 140.6 144.1 148.4
a. RWS supply utilized by Wholesale Customers from 2030 through 2050 is equivalent to Wholesale Customer purchase projections provided to the SFPUC by BAWSCA on March 4, 2026, and includes demands for the cities of San Jose and Santa Clara.
2025 UWMP Supply Reliability Memo
March 11, 2026
Basis of Water Supply Data: With Implementation of the Bay-Delta Plan Amendment
Table 4a: Basis of Water Supply Data [For Table 7-1], Base Year 2030, With Bay-Delta Plan Amendment
Year Type Base
Year
RWS
Volume
Available
(MGD)
% of
Average
Supply
Wholesale
Volume
Available
(MGD)
Notes on Calculation of
Wholesale Allocation of
RWS
Average year 2030 196.6 100% 133.9
Single dry year 2030 147.5 75% 92.2
At shortages 20% or greater,
wholesale allocation is
assumed to be 62.5% and
retail allocation is 37.5%.
Consecutive 1st dry year 2030 147.5 75% 92.2 Same as above.
Consecutive 2nd dry year 2030 123.9 63% 77.4 Same as above.
Consecutive 3rd dry year 2030 123.9 63% 77.4 Same as above.
Consecutive 4th dry year 2030 123.9 63% 77.4 Same as above.
Consecutive 5th dry year 2030 123.9 63% 77.4 Same as above.
Table 4b: Basis of Water Supply Data [For Table 7-1], Base Year 2035, With Bay-Delta Plan Amendment
Year Type Base
Year
RWS
Volume
Available
(MGD)
% of
Average
Supply
Wholesale
Volume
Available
(MGD)
Notes on Calculation of
Wholesale Allocation of
RWS
Average year 2035 197.5 100% 136.3
Single dry year 2035 146.2 74% 91.3
At shortages 20% or
greater, wholesale
allocation is assumed to be
62.5% and retail allocation
is 37.5%.
Consecutive 1st dry year 2035 146.2 74% 91.3 Same as above.
Consecutive 2nd dry year 2035 124.4 63% 77.8 Same as above.
Consecutive 3rd dry year 2035 124.4 63% 77.8 Same as above.
Consecutive 4th dry year 2035 124.4 63% 77.8 Same as above.
Consecutive 5th dry year 2035 124.4 63% 77.8 Same as above.
2025 UWMP Supply Reliability Memo
March 11, 2026
Table 4c: Basis of Water Supply Data [For Table 7-1], Base Year 2040, With Bay-Delta Plan Amendment
Year Type Base
Year
RWS
Volume
Available
(MGD)
% of
Average
Supply
Wholesale
Volume
Available
(MGD)
Notes on Calculation of
Wholesale Allocation of
RWS
Average year 2040 202.5 100% 140.6
Single dry year 2040 145.8 72% 91.1
At shortages 20% or
greater, wholesale
allocation is assumed to be
62.5% and retail allocation
is 37.5%.
Consecutive 1st dry year 2040 145.8 72% 91.1 Same as above.
Consecutive 2nd dry year 2040 123.5 61% 77.2 Same as above.
Consecutive 3rd dry year 2040 123.5 61% 77.2 Same as above.
Consecutive 4th dry year 2040 123.5 61% 77.2 Same as above.
Consecutive 5th dry year 2040 123.5 61% 77.2 Same as above.
Table 4d: Basis of Water Supply Data [For Table 7-1], Base Year 2045, With Bay-Delta Plan Amendment
Year Type Base
Year
RWS
Volume
Available
(MGD)
% of
Average
Supply
Wholesale
Volume
Available
(MGD)
Notes on Calculation of
Wholesale Allocation of
RWS
Average year 2045 208.1 100% 144.1
Single dry year 2045 145.7 70% 91.0
At shortages 20% or
greater, wholesale
allocation is assumed to be
62.5% and retail allocation
is 37.5%.
Consecutive 1st dry year 2045 145.7 70% 91.0 Same as above.
Consecutive 2nd dry year 2045 122.8 59% 76.7 Same as above.
Consecutive 3rd dry year 2045 122.8 59% 76.7 Same as above.
Consecutive 4th dry year 2045 122.8 59% 76.7 Same as above.
Consecutive 5th dry year 2045 122.8 59% 76.7 Same as above.
2025 UWMP Supply Reliability Memo
March 11, 2026
Table 4e: Basis of Water Supply Data [For Table 7-1], Base Year 2050, With Bay-Delta Plan Amendment
Year Type Base
Year
RWS
Volume
Available
(MGD)
% of
Average
Supply
Wholesale
Volume
Available
(MGD)
Notes on Calculation of
Wholesale Allocation of
RWS
Average year 2050 215.1 100% 148.4
Single dry year 2050 146.2 68% 91.4
At shortages 20% or
greater, wholesale
allocation is assumed to be
62.5% and retail allocation
is 37.5%.
Consecutive 1st dry year 2050 146.2 68% 91.4 Same as above.
Consecutive 2nd dry year 2050 122.6 57% 76.6 Same as above.
Consecutive 3rd dry year 2050 122.6 57% 76.6 Same as above.
Consecutive 4th dry year 2050 122.6 57% 76.6 Same as above.
Consecutive 5th dry year 2050 122.6 57% 76.6 Same as above.
Table 4f: Basis of Water Supply Data [For Table 7-1], Base Year 2050, With Bay-Delta Plan Amendment and Wholesale Demands at 184 MGD Supply Assurance Year Type Base
Year
RWS
Volume
Available
(MGD)
% of
Average
Supply
Wholesale
Volume
Available
(MGD)
Notes on Calculation of
Wholesale Allocation of
RWS
Average year 2050 250.7 100% 184.0
Single dry year 2050 145.4 58% 90.9
At shortages 20% or
greater, wholesale
allocation is assumed to be
62.5% and retail allocation
is 37.5%.
Consecutive 1st dry year 2050 145.4 58% 90.9 Same as above.
Consecutive 2nd dry year 2050 120.3 48% 75.2 Same as above.
Consecutive 3rd dry year 2050 120.3 48% 75.2 Same as above.
Consecutive 4th dry year 2050 120.3 48% 75.2 Same as above.
Consecutive 5th dry year 2050 120.3 48% 75.2 Same as above.
2025 UWMP Supply Reliability Memo
March 11, 2026
Table 4g: Projected RWS Supply Availability [Alternative to Table 7-1], Years 2030-2050, With Bay-Delta Plan Amendment
Year Type 2030 2035 2040 2045 2050
2050 (with 184
MGD Supply
Assurance)
Average year 100% 100% 100% 100% 100% 100%
Single dry year 75% 74% 72% 70% 68% 58%
Consecutive 1st dry year 75% 74% 72% 70% 68% 58%
Consecutive 2nd dry year 63% 63% 61% 59% 57% 48%
Consecutive 3rd dry year 63% 63% 61% 59% 57% 48%
Consecutive 4th dry year 63% 63% 61% 59% 57% 48%
Consecutive 5th dry year 63% 63% 61% 59% 57% 48%
2025 UWMP Supply Reliability Memo
March 11, 2026
Basis of Water Supply Data: Without Implementation of the Bay-Delta Plan Amendment
Table 5a: Basis of Water Supply Data [For Table 7-1], Base Year 2030, Without Bay-Delta Plan Amendment
Year Type Base
Year
RWS
Volume
Available
(MGD)
% of
Average
Supply
Wholesale
Volume
Available
(MGD)
Notes on Calculation of
Wholesale Allocation of
RWS
Average year 2030 196.6 100% 133.9
Single dry year 2030 196.6 100% 133.9
Consecutive 1st dry year 2030 196.6 100% 133.9
Consecutive 2nd dry year 2030 196.6 100% 133.9
Consecutive 3rd dry year 2030 196.6 100% 133.9
Consecutive 4th dry year 2030 196.6 100% 133.9
Consecutive 5th dry year 2030 196.6 100% 133.9
Table 5b: Basis of Water Supply Data [For Table 7-1], Base Year 2035, Without Bay-Delta Plan Amendment
Year Type Base
Year
RWS
Volume
Available
(MGD)
% of
Average
Supply
Wholesale
Volume
Available
(MGD)
Notes on Calculation of
Wholesale Allocation of
RWS
Average year 2035 197.5 100% 136.3
Single dry year 2035 197.5 100% 136.3
Consecutive 1st dry year 2035 197.5 100% 136.3
Consecutive 2nd dry year 2035 197.5 100% 136.3
Consecutive 3rd dry year 2035 197.5 100% 136.3
Consecutive 4th dry year 2035 197.5 100% 136.3
Consecutive 5th dry year 2035 197.5 100% 136.3
2025 UWMP Supply Reliability Memo
March 11, 2026
Table 5c: Basis of Water Supply Data [For Table 7-1], Base Year 2040, Without Bay-Delta Plan Amendment
Year Type Base
Year
RWS
Volume
Available
(MGD)
% of
Average
Supply
Wholesale
Volume
Available
(MGD)
Notes on Calculation of
Wholesale Allocation of
RWS
Average year 2040 202.5 100% 140.6
Single dry year 2040 202.5 100% 140.6
Consecutive 1st dry year 2040 202.5 100% 140.6
Consecutive 2nd dry year 2040 202.5 100% 140.6
Consecutive 3rd dry year 2040 202.5 100% 140.6
Consecutive 4th dry year 2040 202.5 100% 140.6
Consecutive 5th dry year 2040 202.5 100% 140.6
Table 5d: Basis of Water Supply Data [For Table 7-1], Base Year 2045, Without Bay-Delta Plan Amendment
Year Type Base
Year
RWS
Volume
Available
(MGD)
% of
Average
Supply
Wholesale
Volume
Available
(MGD)
Notes on Calculation of
Wholesale Allocation of
RWS
Average year 2045 208.1 100% 144.1
Single dry year 2045 208.1 100% 144.1
Consecutive 1st dry year 2045 208.1 100% 144.1
Consecutive 2nd dry year 2045 208.1 100% 144.1
Consecutive 3rd dry year 2045 208.1 100% 144.1
Consecutive 4th dry year 2045 208.1 100% 144.1
Consecutive 5th dry year 2045 208.1 100% 144.1
Table 5e: Basis of Water Supply Data [For Table 7-1], Base Year 2050, Without Bay-Delta Plan Amendment
Year Type Base
Year
RWS
Volume
Available
(MGD)
% of
Average
Supply
Wholesale
Volume
Available
(MGD)
Notes on Calculation of
Wholesale Allocation of
RWS
Average year 2050 215.1 100% 148.4
Single dry year 2050 215.1 100% 148.4
Consecutive 1st dry year 2050 215.1 100% 148.4
Consecutive 2nd dry year 2050 215.1 100% 148.4
Consecutive 3rd dry year 2050 215.1 100% 148.4
Consecutive 4th dry year 2050 215.1 100% 148.4
Consecutive 5th dry year 2050 215.1 100% 148.4
2025 UWMP Supply Reliability Memo
March 11, 2026
Table 5f: Basis of Water Supply Data [For Table 7-1], Base Year 2050, Without Bay-Delta Plan Amendment and Wholesale Demands at 184 MGD Supply Assurance Year Type Base
Year
RWS
Volume
Available
(MGD)
% of
Average
Supply
Wholesale
Volume
Available
(MGD)
Notes on Calculation of
Wholesale Allocation of
RWS
Average year 2050 250.7 100% 184.0
Single dry year 2050 225.6 90% 158.9
At 10% shortage, wholesale
allocation is 64% (144.4 MGD)
and retail allocation is 36%
(81.2 MGD). Retail allocations
above 66.7 MGD are re-
allocated to Wholesale
Customers, per the Water
Supply Agreement. Therefore,
14.5 MGD is added to
wholesale allocation, bringing
it to 158.9 MGD.
Consecutive 1st dry year 2050 225.6 90% 158.9 Same as above.
Consecutive 2nd dry year 2050 225.6 90% 158.9 Same as above.
Consecutive 3rd dry year 2050 225.6 90% 158.9 Same as above.
Consecutive 4th dry year 2050 225.6 90% 158.9 Same as above.
Consecutive 5th dry year 2050 225.6 90% 158.9 Same as above.
Table 5g: Projected RWS Supply [Alternative to Table 7-1], Years 2030-2050, Without Bay- Delta Plan Amendment
Year Type 2030 2035 2040 2045 2050
2050 (with 184
MGD Supply
Assurance)
Average year 100% 100% 100% 100% 100% 100%
Single dry year 100% 100% 100% 100% 100% 90%
Consecutive 1st dry year 100% 100% 100% 100% 100% 90%
Consecutive 2nd dry year 100% 100% 100% 100% 100% 90%
Consecutive 3rd dry year 100% 100% 100% 100% 100% 90%
Consecutive 4th dry year 100% 100% 100% 100% 100% 90%
Consecutive 5th dry year 100% 100% 100% 100% 100% 90%
2025 UWMP Supply Reliability Memo
March 11, 2026
Supply Projections for Consecutive Five Dry Year Sequences
Table 6: Projected Multiple Dry Years RWS Wholesale Allocation [For Table 7-4], With Bay-Delta Plan Amendment
2030 2035 2040 2045 2050 2050 (with 184 MGD
Supply Assurance)
First year 92.2 91.3 91.1 91.0 91.4 90.9
Second year 77.4 77.8 77.2 76.7 76.6 75.2
Third year 77.4 77.8 77.2 76.7 76.6 75.2
Fourth year 77.4 77.8 77.2 76.7 76.6 75.2
Fifth year 77.4 77.8 77.2 76.7 76.6 75.2
Table 7: Projected Multiple Dry Years RWS Wholesale Allocation [For Table 7-4], Without Bay-Delta Plan Amendment
2030 2035 2040 2045 2050 2050 (with 184 MGD
Supply Assurance)
First year 133.9 136.3 140.6 144.1 148.4 158.9
Second year 133.9 136.3 140.6 144.1 148.4 158.9
Third year 133.9 136.3 140.6 144.1 148.4 158.9
Fourth year 133.9 136.3 140.6 144.1 148.4 158.9
Fifth year 133.9 136.3 140.6 144.1 148.4 158.9
Table 8: Projected RWS Supply for 5-Year Drought Risk Assessment [For Table 7-5] Year 2026 2027 2028 2029 2030
Wholesale Purchase
Projectionsa (MGD) 130.9 131.6 132.4 133.2 133.9
RWS Supply Utilized by
Wholesale Customersb (MGD) 130.9 131.6 132.4 133.2 133.9 a. Wholesale Purchase Projections for 2026-2030 assume a linear growth between 2025 actual demands and 2030 projections, as calculated by BAWSCA.
b. This table does not assume implementation of the Bay-Delta Plan Amendment because the start of implementation remains uncertain.
Attachment B: 2025 UWMP Wholesale Customer Dry Year Allocations Basis for SFPUC's Water Supply Reliability Modeling
Actual (2025) and Projected (2030-2050) RWS Purchases
Agency ISG 20251
2030 2035 2040 2045 2050
Alameda CWD 13.76 10.08 11.25 11.56 12.00 12.45 13.76
Brisbane / GVMID 0.98 0.68 0.94 0.95 0.97 0.97 0.97
Burlingame 5.23 3.23 3.92 3.99 4.15 4.30 4.44
Coastside CWD 2.18 1.01 1.17 1.16 1.16 1.16 1.16
CWS Total 35.68 29.50 27.04 26.89 26.93 26.80 26.89
Daly City 4.29 3.55 4.29 4.29 4.29 4.29 4.29
East Palo Alto 3.46 1.72 1.19 1.19 1.19 1.18 1.19
Estero MID 5.90 3.78 3.90 3.92 3.93 3.91 3.90
Hayward 22.09 13.66 14.74 15.66 16.82 18.14 19.71
Hillsborough 4.09 2.32 2.09 2.08 2.09 2.11 2.12
Menlo Park 4.46 2.72 2.58 2.64 2.71 2.76 2.83
Mid-Peninsula WD 3.89 2.34 2.82 2.97 3.18 3.39 3.43
Millbrae 3.15 1.81 1.91 1.99 2.09 2.18 2.29
Milpitas 9.23 4.68 5.30 5.35 5.41 5.46 5.52
Mountain View 12.46 7.69 7.87 8.12 8.59 9.04 9.55
North Coast CWD 3.84 2.58 2.23 2.29 2.37 2.36 2.36
Palo Alto 16.58 9.31 8.30 8.20 8.15 8.15 8.18
Purissima Hills WD 1.63 1.51 1.36 1.35 1.36 1.36 1.37
Redwood City 10.93 7.43 6.84 6.54 6.73 6.91 7.09
San Bruno 3.25 1.03 1.85 2.27 2.68 2.68 2.68
San Jose 3.99 4.50 4.50 4.50 4.50 4.50
Santa Clara 2.91 4.50 4.50 4.50 4.50 4.50
Stanford 3.03 1.59 1.77 1.96 2.02 2.07 2.13
Sunnyvale 12.58 10.28 10.72 11.15 11.92 12.58 12.58
Westborough WD 1.32 0.70 0.82 0.80 0.84 0.88 0.91
Total 184.00 130.1 133.9 136.3 140.6 144.1 148.3
1 Source: FY 2024-25 J-Table
1 of 14
Attachment B: 2025 UWMP Wholesale Customer Dry Year Allocations Basis for SFPUC's Water Supply Reliability Modeling
Actual (2025) and Projected (2026-2030) RWS Purchases
Agency 2025 2026 2027 2028 2029 2030
Alameda CWD 10.08 10.32 10.55 10.78 11.02 11.25
Brisbane / GVMID 0.68 0.73 0.78 0.83 0.89 0.94
Burlingame 3.23 3.36 3.50 3.64 3.78 3.92
Coastside CWD 1.01 1.05 1.08 1.11 1.14 1.17
CWS Total 29.50 29.00 28.51 28.02 27.53 27.04
Daly City 3.55 3.70 3.85 4.00 4.14 4.29
East Palo Alto 1.72 1.62 1.51 1.40 1.30 1.19
Estero MID 3.78 3.80 3.83 3.85 3.88 3.90
Hayward 13.66 13.87 14.09 14.31 14.53 14.74
Hillsborough 2.32 2.27 2.23 2.18 2.14 2.09
Menlo Park 2.72 2.69 2.67 2.64 2.61 2.58
Mid-Peninsula WD 2.34 2.44 2.53 2.63 2.73 2.82
Millbrae 1.81 1.83 1.85 1.87 1.89 1.91
Milpitas 4.68 4.80 4.93 5.05 5.18 5.30
Mountain View 7.69 7.73 7.76 7.80 7.83 7.87
North Coast CWD 2.58 2.51 2.44 2.37 2.30 2.23
Palo Alto 9.31 9.11 8.91 8.71 8.50 8.30
Purissima Hills WD 1.51 1.48 1.45 1.42 1.39 1.36
Redwood City 7.43 7.32 7.20 7.08 6.96 6.84
San Bruno 1.03 1.20 1.36 1.52 1.69 1.85
San Jose 3.99 4.09 4.20 4.30 4.40 4.50
Santa Clara 2.91 3.23 3.54 3.86 4.18 4.50
Stanford 1.59 1.62 1.66 1.70 1.73 1.77
Sunnyvale 10.28 10.37 10.46 10.55 10.63 10.72
Westborough WD 0.70 0.72 0.75 0.77 0.80 0.82
Total 130.1 130.9 131.6 132.4 133.2 133.9
2 of 14
Attachment B: 2025 UWMP Wholesale Customer Dry Year Allocations For UWMP Tables 7-1 through Table 7-4
2025
With BDP
Basis of Water Supply Data
2026 2027 2028 2029 2030
130.12 130.88 131.64 132.40 133.16
130.12 130.88 131.64 132.40 133.16
0% 0% 0% 0% 0%
Projected Supply by Year Type
Agency
2025 RWS
Purchases 2026 2027 2028 2029 2030
Alameda CWD 10.08 10.08 11.25 11.56 12.00 12.45
Brisbane / GVMID 0.68 0.68 0.68 0.68 0.68 0.68
Burlingame 3.23 3.23 3.23 3.23 3.23 3.23
Coastside CWD 1.01 1.01 1.01 1.01 1.01 1.01
CWS Total 29.50 29.50 29.50 29.50 29.50 29.50
Daly City 3.55 3.55 3.55 3.55 3.55 3.55
East Palo Alto 1.72 1.72 1.72 1.72 1.72 1.72
Estero MID 3.78 3.78 3.78 3.78 3.78 3.78
Hayward 13.66 13.66 13.66 13.66 13.66 13.66
Hillsborough 2.32 2.32 2.32 2.32 2.32 2.32
Menlo Park 2.72 2.72 2.72 2.72 2.72 2.72
Mid-Peninsula WD 2.34 2.34 2.34 2.34 2.34 2.34
Millbrae 1.81 1.81 1.81 1.81 1.81 1.81
Milpitas 4.68 4.68 4.68 4.68 4.68 4.68
Mountain View 7.69 7.69 7.69 7.69 7.69 7.69
North Coast CWD 2.58 2.58 2.58 2.58 2.58 2.58
Palo Alto 9.31 9.31 9.31 9.31 9.31 9.31
Purissima Hills WD 1.51 1.51 1.51 1.51 1.51 1.51
Redwood City 7.43 7.43 7.43 7.43 7.43 7.43
San Bruno 1.03 1.03 1.03 1.03 1.03 1.03
San Jose 3.99 3.99 3.99 3.99 3.99 3.99
Santa Clara 2.91 2.91 2.91 2.91 2.91 2.91
Stanford 1.59 1.59 1.59 1.59 1.59 1.59
Sunnyvale 10.28 10.28 10.28 10.28 10.28 10.28
Westborough WD 0.70 0.70 0.70 0.70 0.70 0.70
Total 130.12 130.12 131.28 131.59 132.03 132.48
Percent Cutback
Wholesale RWS Demand
Wholesale RWS Supply
Base Year
Scenario
Consecutive Dry Year
3 of 14
Attachment B: 2025 UWMP Wholesale Customer Dry Year Allocations For UWMP Tables 7-1 through Table 7-4
2030
With BDP
Basis of Water Supply Data
1st/Single 2nd 3rd 4th 5th
133.9 133.9 133.9 133.9 133.9
92.2 77.4 77.4 77.4 77.4
31% 42% 42% 42% 42%
Projected Supply by Year Type
Agency
2030 Proj.
RWS
1st/Single
Dry Year
2nd Dry
Year
3rd Dry
Year
4th Dry
Year
5th Dry
Year
Alameda CWD 11.25 7.75 6.50 6.50 6.50 6.50
Brisbane / GVMID 0.94 0.65 0.54 0.54 0.54 0.54
Burlingame 3.92 2.70 2.27 2.27 2.27 2.27
Coastside CWD 1.17 0.81 0.68 0.68 0.68 0.68
CWS Total 27.04 18.61 15.63 15.63 15.63 15.63
Daly City 4.29 2.95 2.48 2.48 2.48 2.48
East Palo Alto 1.19 0.82 0.69 0.69 0.69 0.69
Estero MID 3.90 2.69 2.25 2.25 2.25 2.25
Hayward 14.74 10.15 8.52 8.52 8.52 8.52
Hillsborough 2.09 1.44 1.21 1.21 1.21 1.21
Menlo Park 2.58 1.78 1.49 1.49 1.49 1.49
Mid-Peninsula WD 2.82 1.94 1.63 1.63 1.63 1.63
Millbrae 1.91 1.31 1.10 1.10 1.10 1.10
Milpitas 5.30 3.65 3.06 3.06 3.06 3.06
Mountain View 7.87 5.42 4.55 4.55 4.55 4.55
North Coast CWD 2.23 1.54 1.29 1.29 1.29 1.29
Palo Alto 8.30 5.72 4.80 4.80 4.80 4.80
Purissima Hills WD 1.36 0.94 0.79 0.79 0.79 0.79
Redwood City 6.84 4.71 3.95 3.95 3.95 3.95
San Bruno 1.85 1.27 1.07 1.07 1.07 1.07
San Jose 4.50 3.10 2.60 2.60 2.60 2.60
Santa Clara 4.50 3.10 2.60 2.60 2.60 2.60
Stanford 1.77 1.22 1.02 1.02 1.02 1.02
Sunnyvale 10.72 7.38 6.20 6.20 6.20 6.20
Westborough WD 0.82 0.57 0.48 0.48 0.48 0.48
Total 133.92 92.2 77.4 77.4 77.4 77.4
Percent Cutback
Wholesale RWS Demand
Wholesale RWS Supply
Base Year
Scenario
Consecutive Dry Year
4 of 14
Attachment B: 2025 UWMP Wholesale Customer Dry Year Allocations For UWMP Tables 7-1 through Table 7-4
2035
With BDP
Basis of Water Supply Data
1st/Single 2nd 3rd 4th 5th
136.32 136.32 136.32 136.32 136.32
91.3 77.8 77.8 77.8 77.8
33% 43% 43% 43% 43%
Projected Supply by Year Type
Agency
2035 Proj.
RWS
1st/Single
Dry Year
2nd Dry
Year
3rd Dry
Year
4th Dry
Year
5th Dry
Year
Alameda CWD 11.56 7.74 6.60 6.60 6.60 6.60
Brisbane / GVMID 0.95 0.64 0.54 0.54 0.54 0.54
Burlingame 3.99 2.67 2.28 2.28 2.28 2.28
Coastside CWD 1.16 0.78 0.66 0.66 0.66 0.66
CWS Total 26.89 18.01 15.35 15.35 15.35 15.35
Daly City 4.29 2.87 2.45 2.45 2.45 2.45
East Palo Alto 1.19 0.80 0.68 0.68 0.68 0.68
Estero MID 3.92 2.63 2.24 2.24 2.24 2.24
Hayward 15.66 10.49 8.93 8.93 8.93 8.93
Hillsborough 2.08 1.39 1.19 1.19 1.19 1.19
Menlo Park 2.64 1.77 1.51 1.51 1.51 1.51
Mid-Peninsula WD 2.97 1.99 1.69 1.69 1.69 1.69
Millbrae 1.99 1.33 1.14 1.14 1.14 1.14
Milpitas 5.35 3.58 3.05 3.05 3.05 3.05
Mountain View 8.12 5.44 4.63 4.63 4.63 4.63
North Coast CWD 2.29 1.53 1.31 1.31 1.31 1.31
Palo Alto 8.20 5.49 4.68 4.68 4.68 4.68
Purissima Hills WD 1.35 0.90 0.77 0.77 0.77 0.77
Redwood City 6.54 4.38 3.73 3.73 3.73 3.73
San Bruno 2.27 1.52 1.30 1.30 1.30 1.30
San Jose 4.50 3.01 2.57 2.57 2.57 2.57
Santa Clara 4.50 3.01 2.57 2.57 2.57 2.57
Stanford 1.96 1.31 1.12 1.12 1.12 1.12
Sunnyvale 11.15 7.47 6.36 6.36 6.36 6.36
Westborough WD 0.80 0.54 0.46 0.46 0.46 0.46
Total 136.32 91.3 77.8 77.8 77.8 77.8
Percent Cutback
Base Year
Scenario
Consecutive Dry Year
Wholesale RWS Demand
Wholesale RWS Supply
5 of 14
Attachment B: 2025 UWMP Wholesale Customer Dry Year Allocations For UWMP Tables 7-1 through Table 7-4
2040
With BDP
Basis of Water Supply Data
1st/Single 2nd 3rd 4th 5th
140.57 140.57 140.57 140.57 140.57
91.1 77.2 77.2 77.2 77.2
35% 45% 45% 45% 45%
Projected Supply by Year Type
Agency
2040 Proj.
RWS
1st/Single
Dry Year
2nd Dry
Year
3rd Dry
Year
4th Dry
Year
5th Dry
Year
Alameda CWD 12.00 7.78 6.59 6.59 6.59 6.59
Brisbane / GVMID 0.97 0.63 0.53 0.53 0.53 0.53
Burlingame 4.15 2.69 2.28 2.28 2.28 2.28
Coastside CWD 1.16 0.75 0.64 0.64 0.64 0.64
CWS Total 26.93 17.45 14.79 14.79 14.79 14.79
Daly City 4.29 2.78 2.36 2.36 2.36 2.36
East Palo Alto 1.19 0.77 0.65 0.65 0.65 0.65
Estero MID 3.93 2.54 2.16 2.16 2.16 2.16
Hayward 16.82 10.90 9.24 9.24 9.24 9.24
Hillsborough 2.09 1.35 1.15 1.15 1.15 1.15
Menlo Park 2.71 1.75 1.49 1.49 1.49 1.49
Mid-Peninsula WD 3.18 2.06 1.75 1.75 1.75 1.75
Millbrae 2.09 1.35 1.15 1.15 1.15 1.15
Milpitas 5.41 3.51 2.97 2.97 2.97 2.97
Mountain View 8.59 5.57 4.72 4.72 4.72 4.72
North Coast CWD 2.37 1.53 1.30 1.30 1.30 1.30
Palo Alto 8.15 5.28 4.48 4.48 4.48 4.48
Purissima Hills WD 1.36 0.88 0.75 0.75 0.75 0.75
Redwood City 6.73 4.36 3.69 3.69 3.69 3.69
San Bruno 2.68 1.74 1.47 1.47 1.47 1.47
San Jose 4.50 2.92 2.47 2.47 2.47 2.47
Santa Clara 4.50 2.92 2.47 2.47 2.47 2.47
Stanford 2.02 1.31 1.11 1.11 1.11 1.11
Sunnyvale 11.92 7.73 6.55 6.55 6.55 6.55
Westborough WD 0.84 0.55 0.46 0.46 0.46 0.46
Total 140.57 91.1 77.2 77.2 77.2 77.2
Base Year
Scenario
Consecutive Dry Year
Wholesale RWS Demand
Wholesale RWS Supply
Percent Cutback
6 of 14
Attachment B: 2025 UWMP Wholesale Customer Dry Year Allocations For UWMP Tables 7-1 through Table 7-4
2045
With BDP
Basis of Water Supply Data
1st/Single 2nd 3rd 4th 5th
144.11 144.11 144.11 144.11 144.11
91 76.7 76.7 76.7 76.7
37% 47% 47% 47% 47%
Projected Supply by Year Type
Agency
2045 Proj.
RWS
1st/Single
Dry Year
2nd Dry
Year
3rd Dry
Year
4th Dry
Year
5th Dry
Year
Alameda CWD 12.45 7.86 6.63 6.63 6.63 6.63
Brisbane / GVMID 0.97 0.61 0.52 0.52 0.52 0.52
Burlingame 4.30 2.72 2.29 2.29 2.29 2.29
Coastside CWD 1.16 0.73 0.62 0.62 0.62 0.62
CWS Total 26.80 16.92 14.26 14.26 14.26 14.26
Daly City 4.29 2.71 2.28 2.28 2.28 2.28
East Palo Alto 1.18 0.75 0.63 0.63 0.63 0.63
Estero MID 3.91 2.47 2.08 2.08 2.08 2.08
Hayward 18.14 11.45 9.65 9.65 9.65 9.65
Hillsborough 2.11 1.33 1.12 1.12 1.12 1.12
Menlo Park 2.76 1.75 1.47 1.47 1.47 1.47
Mid-Peninsula WD 3.39 2.14 1.80 1.80 1.80 1.80
Millbrae 2.18 1.38 1.16 1.16 1.16 1.16
Milpitas 5.46 3.45 2.91 2.91 2.91 2.91
Mountain View 9.04 5.71 4.81 4.81 4.81 4.81
North Coast CWD 2.36 1.49 1.26 1.26 1.26 1.26
Palo Alto 8.15 5.14 4.34 4.34 4.34 4.34
Purissima Hills WD 1.36 0.86 0.72 0.72 0.72 0.72
Redwood City 6.91 4.36 3.68 3.68 3.68 3.68
San Bruno 2.68 1.69 1.43 1.43 1.43 1.43
San Jose 4.50 2.84 2.40 2.40 2.40 2.40
Santa Clara 4.50 2.84 2.40 2.40 2.40 2.40
Stanford 2.07 1.31 1.10 1.10 1.10 1.10
Sunnyvale 12.58 7.94 6.70 6.70 6.70 6.70
Westborough WD 0.88 0.55 0.47 0.47 0.47 0.47
Total 144.11 91.0 76.7 76.7 76.7 76.7
Percent Cutback
Base Year
Scenario
Consecutive Dry Year
Wholesale RWS Demand
Wholesale RWS Supply
7 of 14
Attachment B: 2025 UWMP Wholesale Customer Dry Year Allocations For UWMP Tables 7-1 through Table 7-4
2050
With BDP
Basis of Water Supply Data
1st/Single 2nd 3rd 4th 5th
148.35 148.35 148.35 148.35 148.35
91.4 76.6 76.6 76.6 76.6
38% 48% 48% 48% 48%
Projected Supply by Year Type
Agency
2050 Proj.
RWS
1st/Single
Dry Year
2nd Dry
Year
3rd Dry
Year
4th Dry
Year
5th Dry
Year
Alameda CWD 13.76 8.48 7.11 7.11 7.11 7.11
Brisbane / GVMID 0.97 0.60 0.50 0.50 0.50 0.50
Burlingame 4.44 2.74 2.29 2.29 2.29 2.29
Coastside CWD 1.16 0.71 0.60 0.60 0.60 0.60
CWS Total 26.89 16.57 13.89 13.89 13.89 13.89
Daly City 4.29 2.64 2.22 2.22 2.22 2.22
East Palo Alto 1.19 0.73 0.61 0.61 0.61 0.61
Estero MID 3.90 2.40 2.01 2.01 2.01 2.01
Hayward 19.71 12.14 10.17 10.17 10.17 10.17
Hillsborough 2.12 1.31 1.09 1.09 1.09 1.09
Menlo Park 2.83 1.75 1.46 1.46 1.46 1.46
Mid-Peninsula WD 3.43 2.11 1.77 1.77 1.77 1.77
Millbrae 2.29 1.41 1.18 1.18 1.18 1.18
Milpitas 5.52 3.40 2.85 2.85 2.85 2.85
Mountain View 9.55 5.88 4.93 4.93 4.93 4.93
North Coast CWD 2.36 1.46 1.22 1.22 1.22 1.22
Palo Alto 8.18 5.04 4.22 4.22 4.22 4.22
Purissima Hills WD 1.37 0.84 0.71 0.71 0.71 0.71
Redwood City 7.09 4.37 3.66 3.66 3.66 3.66
San Bruno 2.68 1.65 1.38 1.38 1.38 1.38
San Jose 4.50 2.77 2.32 2.32 2.32 2.32
Santa Clara 4.50 2.77 2.32 2.32 2.32 2.32
Stanford 2.13 1.31 1.10 1.10 1.10 1.10
Sunnyvale 12.58 7.75 6.50 6.50 6.50 6.50
Westborough WD 0.91 0.56 0.47 0.47 0.47 0.47
Total 148.35 91.4 76.6 76.6 76.6 76.6
Percent Cutback
Base Year
Scenario
Consecutive Dry Year
Wholesale RWS Demand
Wholesale RWS Supply
8 of 14
Attachment B: 2025 UWMP Wholesale Customer Dry Year Allocations For UWMP Tables 7-1 through Table 7-4
2026
Without BDP
Basis of Water Supply Data
2026 2027 2028 2029 2030
130.1 130.9 131.6 132.4 133.2
130.1 130.9 131.6 132.4 133.2
0% 0% 0% 0% 0%
Projected Supply by Year Type
Agency
2025 RWS
Purchases 2026 2027 2028 2029 2030
Alameda CWD 10.08 10.08 11.25 11.56 12.00 12.45
Brisbane / GVMID 0.68 0.68 0.68 0.68 0.68 0.68
Burlingame 3.23 3.23 3.23 3.23 3.23 3.23
Coastside CWD 1.01 1.01 1.01 1.01 1.01 1.01
CWS Total 29.50 29.50 29.50 29.50 29.50 29.50
Daly City 3.55 3.55 3.55 3.55 3.55 3.55
East Palo Alto 1.72 1.72 1.72 1.72 1.72 1.72
Estero MID 3.78 3.78 3.78 3.78 3.78 3.78
Hayward 13.66 13.66 13.66 13.66 13.66 13.66
Hillsborough 2.32 2.32 2.32 2.32 2.32 2.32
Menlo Park 2.72 2.72 2.72 2.72 2.72 2.72
Mid-Peninsula WD 2.34 2.34 2.34 2.34 2.34 2.34
Millbrae 1.81 1.81 1.81 1.81 1.81 1.81
Milpitas 4.68 4.68 4.68 4.68 4.68 4.68
Mountain View 7.69 7.69 7.69 7.69 7.69 7.69
North Coast CWD 2.58 2.58 2.58 2.58 2.58 2.58
Palo Alto 9.31 9.31 9.31 9.31 9.31 9.31
Purissima Hills WD 1.51 1.51 1.51 1.51 1.51 1.51
Redwood City 7.43 7.43 7.43 7.43 7.43 7.43
San Bruno 1.03 1.03 1.03 1.03 1.03 1.03
San Jose 3.99 3.99 3.99 3.99 3.99 3.99
Santa Clara 2.91 2.91 2.91 2.91 2.91 2.91
Stanford 1.59 1.59 1.59 1.59 1.59 1.59
Sunnyvale 10.28 10.28 10.28 10.28 10.28 10.28
Westborough WD 0.70 0.70 0.70 0.70 0.70 0.70
Total 130.12 130.12 131.28 131.59 132.03 132.48
Wholesale RWS Supply
Percent Cutback
Consecutive Dry Year
Wholesale RWS Demand
Base Year
Scenario
9 of 14
Attachment B: 2025 UWMP Wholesale Customer Dry Year Allocations For UWMP Tables 7-1 through Table 7-4
2030
Without BDP
Basis of Water Supply Data
1st/Single 2nd 3rd 4th 5th
133.9 133.9 133.9 133.9 133.9
133.9 133.9 133.9 133.9 133.9
0% 0% 0% 0% 0%
Projected Supply by Year Type
Agency
2030 Proj.
RWS
1st/Single
Dry Year
2nd Dry
Year
3rd Dry
Year
4th Dry
Year
5th Dry
Year
Alameda CWD 11.25 11.25 11.25 11.25 11.25 11.25
Brisbane / GVMID 0.94 0.94 0.94 0.94 0.94 0.94
Burlingame 3.92 3.92 3.92 3.92 3.92 3.92
Coastside CWD 1.17 1.17 1.17 1.17 1.17 1.17
CWS Total 27.04 27.04 27.04 27.04 27.04 27.04
Daly City 4.29 4.29 4.29 4.29 4.29 4.29
East Palo Alto 1.19 1.19 1.19 1.19 1.19 1.19
Estero MID 3.90 3.90 3.90 3.90 3.90 3.90
Hayward 14.74 14.74 14.74 14.74 14.74 14.74
Hillsborough 2.09 2.09 2.09 2.09 2.09 2.09
Menlo Park 2.58 2.58 2.58 2.58 2.58 2.58
Mid-Peninsula WD 2.82 2.82 2.82 2.82 2.82 2.82
Millbrae 1.91 1.91 1.91 1.91 1.91 1.91
Milpitas 5.30 5.30 5.30 5.30 5.30 5.30
Mountain View 7.87 7.87 7.87 7.87 7.87 7.87
North Coast CWD 2.23 2.23 2.23 2.23 2.23 2.23
Palo Alto 8.30 8.30 8.30 8.30 8.30 8.30
Purissima Hills WD 1.36 1.36 1.36 1.36 1.36 1.36
Redwood City 6.84 6.84 6.84 6.84 6.84 6.84
San Bruno 1.85 1.85 1.85 1.85 1.85 1.85
San Jose 4.50 4.50 4.50 4.50 4.50 4.50
Santa Clara 4.50 4.50 4.50 4.50 4.50 4.50
Stanford 1.77 1.77 1.77 1.77 1.77 1.77
Sunnyvale 10.72 10.72 10.72 10.72 10.72 10.72
Westborough WD 0.82 0.82 0.82 0.82 0.82 0.82
Total 133.92 133.92 133.92 133.92 133.92 133.92
Wholesale RWS Supply
Percent Cutback
Consecutive Dry Year
Wholesale RWS Demand
Base Year
Scenario
10 of 14
Attachment B: 2025 UWMP Wholesale Customer Dry Year Allocations For UWMP Tables 7-1 through Table 7-4
2035
Without BDP
Basis of Water Supply Data
1st/Single 2nd 3rd 4th 5th
136.3 136.3 136.3 136.3 136.3
136.3 136.3 136.3 136.3 136.3
0% 0% 0% 0% 0%
Projected Supply by Year Type
Agency
2035 Proj.
RWS
1st/Single
Dry Year
2nd Dry
Year
3rd Dry
Year
4th Dry
Year
5th Dry
Year
Alameda CWD 11.56 11.56 11.56 11.56 11.56 11.56
Brisbane / GVMID 0.95 0.95 0.95 0.95 0.95 0.95
Burlingame 3.99 3.99 3.99 3.99 3.99 3.99
Coastside CWD 1.16 1.16 1.16 1.16 1.16 1.16
CWS Total 26.89 26.89 26.89 26.89 26.89 26.89
Daly City 4.29 4.29 4.29 4.29 4.29 4.29
East Palo Alto 1.19 1.19 1.19 1.19 1.19 1.19
Estero MID 3.92 3.92 3.92 3.92 3.92 3.92
Hayward 15.66 15.66 15.66 15.66 15.66 15.66
Hillsborough 2.08 2.08 2.08 2.08 2.08 2.08
Menlo Park 2.64 2.64 2.64 2.64 2.64 2.64
Mid-Peninsula WD 2.97 2.97 2.97 2.97 2.97 2.97
Millbrae 1.99 1.99 1.99 1.99 1.99 1.99
Milpitas 5.35 5.35 5.35 5.35 5.35 5.35
Mountain View 8.12 8.12 8.12 8.12 8.12 8.12
North Coast CWD 2.29 2.29 2.29 2.29 2.29 2.29
Palo Alto 8.20 8.20 8.20 8.20 8.20 8.20
Purissima Hills WD 1.35 1.35 1.35 1.35 1.35 1.35
Redwood City 6.54 6.54 6.54 6.54 6.54 6.54
San Bruno 2.27 2.27 2.27 2.27 2.27 2.27
San Jose 4.50 4.50 4.50 4.50 4.50 4.50
Santa Clara 4.50 4.50 4.50 4.50 4.50 4.50
Stanford 1.96 1.96 1.96 1.96 1.96 1.96
Sunnyvale 11.15 11.15 11.15 11.15 11.15 11.15
Westborough WD 0.80 0.80 0.80 0.80 0.80 0.80
Total 136.32 136.32 136.32 136.32 136.32 136.32
Wholesale RWS Supply
Percent Cutback
Consecutive Dry Year
Wholesale RWS Demand
Base Year
Scenario
11 of 14
Attachment B: 2025 UWMP Wholesale Customer Dry Year Allocations For UWMP Tables 7-1 through Table 7-4
2040
Without BDP
Basis of Water Supply Data
1st/Single 2nd 3rd 4th 5th
140.6 140.6 140.6 140.6 140.6
140.6 140.6 140.6 140.6 140.6
0% 0% 0% 0% 0%
Projected Supply by Year Type
Agency
2040 Proj.
RWS
1st/Single
Dry Year
2nd Dry
Year
3rd Dry
Year
4th Dry
Year
5th Dry
Year
Alameda CWD 12.00 12.00 12.00 12.00 12.00 12.00
Brisbane / GVMID 0.97 0.97 0.97 0.97 0.97 0.97
Burlingame 4.15 4.15 4.15 4.15 4.15 4.15
Coastside CWD 1.16 1.16 1.16 1.16 1.16 1.16
CWS Total 26.93 26.93 26.93 26.93 26.93 26.93
Daly City 4.29 4.29 4.29 4.29 4.29 4.29
East Palo Alto 1.19 1.19 1.19 1.19 1.19 1.19
Estero MID 3.93 3.93 3.93 3.93 3.93 3.93
Hayward 16.82 16.82 16.82 16.82 16.82 16.82
Hillsborough 2.09 2.09 2.09 2.09 2.09 2.09
Menlo Park 2.71 2.71 2.71 2.71 2.71 2.71
Mid-Peninsula WD 3.18 3.18 3.18 3.18 3.18 3.18
Millbrae 2.09 2.09 2.09 2.09 2.09 2.09
Milpitas 5.41 5.41 5.41 5.41 5.41 5.41
Mountain View 8.59 8.59 8.59 8.59 8.59 8.59
North Coast CWD 2.37 2.37 2.37 2.37 2.37 2.37
Palo Alto 8.15 8.15 8.15 8.15 8.15 8.15
Purissima Hills WD 1.36 1.36 1.36 1.36 1.36 1.36
Redwood City 6.73 6.73 6.73 6.73 6.73 6.73
San Bruno 2.68 2.68 2.68 2.68 2.68 2.68
San Jose 4.50 4.50 4.50 4.50 4.50 4.50
Santa Clara 4.50 4.50 4.50 4.50 4.50 4.50
Stanford 2.02 2.02 2.02 2.02 2.02 2.02
Sunnyvale 11.92 11.92 11.92 11.92 11.92 11.92
Westborough WD 0.84 0.84 0.84 0.84 0.84 0.84
Total 140.57 140.57 140.57 140.57 140.57 140.57
Wholesale RWS Supply
Percent Cutback
Consecutive Dry Year
Wholesale RWS Demand
Base Year
Scenario
12 of 14
Attachment B: 2025 UWMP Wholesale Customer Dry Year Allocations For UWMP Tables 7-1 through Table 7-4
2045
Without BDP
Basis of Water Supply Data
1st/Single 2nd 3rd 4th 5th
144.1 144.1 144.1 144.1 144.1
144.1 144.1 144.1 144.1 144.1
0% 0% 0% 0% 0%
Projected Supply by Year Type
Agency
2045 Proj.
RWS
1st/Single
Dry Year
2nd Dry
Year
3rd Dry
Year
4th Dry
Year
5th Dry
Year
Alameda CWD 12.45 12.45 12.45 12.45 12.45 12.45
Brisbane / GVMID 0.97 0.97 0.97 0.97 0.97 0.97
Burlingame 4.30 4.30 4.30 4.30 4.30 4.30
Coastside CWD 1.16 1.16 1.16 1.16 1.16 1.16
CWS Total 26.80 26.80 26.80 26.80 26.80 26.80
Daly City 4.29 4.29 4.29 4.29 4.29 4.29
East Palo Alto 1.18 1.18 1.18 1.18 1.18 1.18
Estero MID 3.91 3.91 3.91 3.91 3.91 3.91
Hayward 18.14 18.14 18.14 18.14 18.14 18.14
Hillsborough 2.11 2.11 2.11 2.11 2.11 2.11
Menlo Park 2.76 2.76 2.76 2.76 2.76 2.76
Mid-Peninsula WD 3.39 3.39 3.39 3.39 3.39 3.39
Millbrae 2.18 2.18 2.18 2.18 2.18 2.18
Milpitas 5.46 5.46 5.46 5.46 5.46 5.46
Mountain View 9.04 9.04 9.04 9.04 9.04 9.04
North Coast CWD 2.36 2.36 2.36 2.36 2.36 2.36
Palo Alto 8.15 8.15 8.15 8.15 8.15 8.15
Purissima Hills WD 1.36 1.36 1.36 1.36 1.36 1.36
Redwood City 6.91 6.91 6.91 6.91 6.91 6.91
San Bruno 2.68 2.68 2.68 2.68 2.68 2.68
San Jose 4.50 4.50 4.50 4.50 4.50 4.50
Santa Clara 4.50 4.50 4.50 4.50 4.50 4.50
Stanford 2.07 2.07 2.07 2.07 2.07 2.07
Sunnyvale 12.58 12.58 12.58 12.58 12.58 12.58
Westborough WD 0.88 0.88 0.88 0.88 0.88 0.88
Total 144.11 144.11 144.11 144.11 144.11 144.11
Wholesale RWS Supply
Percent Cutback
Consecutive Dry Year
Wholesale RWS Demand
Base Year
Scenario
13 of 14
Attachment B: 2025 UWMP Wholesale Customer Dry Year Allocations For UWMP Tables 7-2 through Table 7-4
2050
Without BDP
Basis of Water Supply Data
1st/Single 2nd 3rd 4th 5th
148.3 148.3 148.3 148.3 148.3
148.3 148.3 148.3 148.3 148.3
0% 0% 0% 0% 0%
Projected Supply by Year Type
Agency
2050 Proj.
RWS
1st/Single
Dry Year
2nd Dry
Year
3rd Dry
Year
4th Dry
Year
5th Dry
Year
Alameda CWD 13.76 13.76 13.76 13.76 13.76 13.76
Brisbane / GVMID 0.97 0.97 0.97 0.97 0.97 0.97
Burlingame 4.44 4.44 4.44 4.44 4.44 4.44
Coastside CWD 1.16 1.16 1.16 1.16 1.16 1.16
CWS Total 26.89 26.89 26.89 26.89 26.89 26.89
Daly City 4.29 4.29 4.29 4.29 4.29 4.29
East Palo Alto 1.19 1.19 1.19 1.19 1.19 1.19
Estero MID 3.90 3.90 3.90 3.90 3.90 3.90
Hayward 19.71 19.71 19.71 19.71 19.71 19.71
Hillsborough 2.12 2.12 2.12 2.12 2.12 2.12
Menlo Park 2.83 2.83 2.83 2.83 2.83 2.83
Mid-Peninsula WD 3.43 3.43 3.43 3.43 3.43 3.43
Millbrae 2.29 2.29 2.29 2.29 2.29 2.29
Milpitas 5.52 5.52 5.52 5.52 5.52 5.52
Mountain View 9.55 9.55 9.55 9.55 9.55 9.55
North Coast CWD 2.36 2.36 2.36 2.36 2.36 2.36
Palo Alto 8.18 8.18 8.18 8.18 8.18 8.18
Purissima Hills WD 1.37 1.37 1.37 1.37 1.37 1.37
Redwood City 7.09 7.09 7.09 7.09 7.09 7.09
San Bruno 2.68 2.68 2.68 2.68 2.68 2.68
San Jose 4.50 4.50 4.50 4.50 4.50 4.50
Santa Clara 4.50 4.50 4.50 4.50 4.50 4.50
Stanford 2.13 2.13 2.13 2.13 2.13 2.13
Sunnyvale 12.58 12.58 12.58 12.58 12.58 12.58
Westborough WD 0.91 0.91 0.91 0.91 0.91 0.91
Total 148.35 148.35 148.35 148.35 148.35 148.35
Percent Cutback
Wholesale RWS Supply
Wholesale RWS Demand
Consecutive Dry Year
Scenario
Base Year
14 of 14
Valley Water - Water Supply Reliability Tables
Water Supply
2030
2035
2040
2045
2050
Surface water
56,000
76,000
77,000
76,000
76,000
Imported water
177,000
163,000
163,000
164,000
164,000
SFPUC Supply
50,000
51,000
52,000
53,000
54,000
Natural Groundwater Recharge
61,000
61,000
60,000
60,000
60,000
Recycled water (potable)
0 24,000
24,000
24,000
24,000
Recycled water (non-potable)
20,000
22,000
24,000
26,000
28,000
Supply Total
365,000
397,000
400,000
403,000
406,000
Demand Total
330,000
330,000
330,000
330,000
330,000
Difference (Surplus)
35,000
67,000
70,000
73,000
76,000
Water Supply
2030
2035
2040
2045
2050
Surface water
11,000
10,000
10,000
10,000
10,000
Imported water
42,000
37,000
37,000
37,000
37,000
SFPUC Supply
30,000
31,000
32,000
33,000
32,000
Natural Groundwater Recharge
47,000
48,000
47,000
47,000
47,000
Recycled water (potable)
0 24,000
24,000
24,000
24,000
Recycled water (non-potable)
20,000
22,000
24,000
26,000
28,000
Supply from Storage
181,000
250,000
246,000
245,000
246,000
Supply Total
331,000
422,000
420,000
422,000
424,000
Demand Total
330,000
330,000
330,000
330,000
330,000
Difference
1,000
92,000
90,000
92,000
94,000
Multiple Dry Years Supplies and Demands (Acre-feet rounded to nearest 1,000) 2030
2035
2040
2045
2050
Supply
232,000
242,000
243,000
225,000
223,000
Supply from Storage
175,000
245,000
239,000
242,000
242,000
Demand Totals
330,000
330,000
330,000
330,000
330,000
Surplus/(Shortfall)
77,000
157,000
152,000
137,000
135,000
WSCP Actions
Revised Difference
Supply
322,000
287,000
287,000
267,000
268,000
Supply from Storage
136,000
212,000
196,000
188,000
186,000
Demand Totals
330,000
330,000
330,000
330,000
330,000
Surplus/(Shortfall)
128,000
169,000
153,000
125,000
124,000
WSCP Actions
Revised Difference
Supply
262,000
231,000
232,000
203,000
204,000
Supply from Storage
121,000
186,000
174,000
160,000
159,000
Demand Totals
330,000
330,000
330,000
330,000
330,000
Surplus/(Shortfall)
53,000
87,000
76,000
33,000
33,000
WSCP Actions
Revised Difference
Supply
266,000
241,000
240,000
241,000
241,000
Supply from Storage
35,000
121,000
106,000
63,000
63,000
Demand Totals
330,000
330,000
330,000
330,000
330,000
Surplus/(Shortfall)
(29,000)
32,000
16,000
(26,000)
(26,000)
WSCP Actions
29,000
26,000
26,000
Revised Difference
0 0
0 Supply
277,000
304,000
309,000
282,000
282,000
Supply from Storage
32,000
54,000
30,000
30,000
30,000
Demand Totals
330,000
330,000
330,000
330,000
330,000
Surplus/(Shortfall)
(21,000)
28,000
9,000
(18,000)
(18,000)
WSCP Actions
21,000
18,000
18,000
Revised Difference
0 0
0 Fifth Year
Average Year Supplies and Demands (Acre-feet rounded to nearlest 1,000) Single Dry Year Supplies and Demands (Acre-feet rounded to nearest 1,000) First Year
Second Year
Third Year
Fourth Year
General
Values are rounded to the nearest 1,000 AF.
Imported Water
Based on CalSim 3 model runs for Delivery Capability Report 2025.
SFPUC Supplies
SFPUC deliveries are based on modeled supply reliability results and estimates provided by BAWSCA; values reflect scenarios that assume implementation of the Bay-Delta Plan Amendment.
Recycled Water
Non-potable recycled water supplies are based on projections provided by retailers and reflect anticipated future recycled water use. Potable recycled water supplies assumes implementation of the Pure Water Silicon Valley.
Demand
All model demands are based on the WSMP countywide demand of 330 TAF.
Supply Portfolio
Assumes Valley Water's Water Supply Master Plan 2050 low-cost portfolio:
Semitropic storage (350 TAF) through 2035; groundwater banking (250 TAF) starting 2040; Sisk Reservoir expansion in 2035; DCP in 2045; Pure Water Silicon Valley in 2035.
Operations
Under normal year conditions, sustainable storage is maintained and no withdrawals from long-term storage are assumed; demands are met by incoming supplies. During droughts, stored water accumulated during normal and wet years is used to bridge gaps between reduced incoming supplies and demand.
Hydrology
Model period is 1922–2021; single dry year is 1977; multi-year drought is 1988–1992; this remains the most severe extended drought in the record.
Infrastructure
Anderson Reservoir is dewatered in 2030 and operational by 2035. Seismic upgrades to Calero, Guadalupe, Almaden, and Anderson are complete in the 2035 model runs and later.
Supply Definition
Reasonably available supply is water in storage above thresholds for emergency needs, subsidence protection, and operational withdrawal limits for each storage facility.
Shortage Response
In the 5-year drought, WSCP actions are required in years 4 and 5 for some future scenarios; these shortages are addressed through demand reduction and supply augmentation.
Notes
Water Shortage Contingency Plan
Appendix G
PREPARED BY
City of Santa Clara
Water Shortage Contingency Plan
PREPARED FOR
City of Santa Clara
DRAFT PLAN | MAY 2026
DRAFT REPORT | MAY 2026
EARYEAR2020
City of Santa Clara
Water Shortage Contingency Plan
Prepared for
City of Santa Clara
Project No. 1078-60-23-01
Prepared by: Elizabeth Drayer, PE, RCE #46872 Date
QA/QC Review: Rhodora Biagtan, PE, RCE #59371 Date
n-c-1078-60-23-01-wp-2025uwmp-appendices
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2025 Water Shortage Contingency Plan
May 2026
Table of Contents
1.0 Introduction ............................................................................................................. 1
2.0 Water Supply Reliability Analysis .......................................................................... 1
3.0 Annual Water Supply and Demand Assessment Procedures ............................. 1
3.1 Decision-Making Process .................................................................................... 2
3.1.1 AWSDA Finding: Sufficient Water Supply to Meet Expected Demands ...... 3
3.1.2 AWSDA Finding: Available Water Supply Will Not Meet Demands ............. 3
3.2 Key Data Inputs ................................................................................................... 4
3.3 Assessment Methodology .................................................................................... 5
4.0 Standard Water Shortage Levels ........................................................................... 6
5.0 Shortage Response Actions .................................................................................. 7
5.1 Demand Reduction Actions ................................................................................. 8
5.2 Additional Mandatory Restrictions ...................................................................... 10
5.2.1 Water Features and Swimming Pools ....................................................... 10
5.3 Supply Augmentation and Other Actions ........................................................... 10
5.4 Locally Appropriate Operational Changes ......................................................... 11
5.5 Emergency Response Plan................................................................................ 11
6.0 Communication Protocols .................................................................................... 12
6.1 Communication for Foreseeable Events ............................................................ 12
6.2 Communication for Unforeseeable Events ......................................................... 13
7.0 Compliance and Enforcement .............................................................................. 13
7.1 Compliance and Enforcement Procedures ........................................................ 13
8.0 Legal Authorities ................................................................................................... 14
9.0 Financial Consequences of WSCP ...................................................................... 14
10.0 Monitoring and Reporting................................................................................... 15
11.0 WSCP Refinement Procedures .......................................................................... 15
12.0 Plan Adoption, Submittal, and availability ........................................................ 16
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2025 Water Shortage Contingency Plan
May 2026
Table of Contents
LIST OF TABLES
Table 1. Schedule of Annual Water Supply and Demand Assessment (AWSDA) Activities ...................................................................................... 2 Table 2. Schedule of Decision-Making Activities if AWSDA Indicates Supply May Not Meet Demands .............................................................................. 4 Table 3. Water Shortage Contingency Plan Levels (DWR Table 8-1) ........................ 7 Table 4. Demand Reduction Actions (DWR Table 8-3 Retail) ................................... 9 Table 5. Supply Augmentation and Other Actions (DWR Table 8-2 Retail) ............. 11
LIST OF ACRONYMS AND ABBREVIATIONS
AB Assembly Bill 1
AMI Advanced Metering Infrastructure 6
AMR Automated Meter Reading 15
AWSDA Annual Water Supply and Demand Assessment 2
City City of Santa Clara 1
County Santa Clara County
CWC California Water Code
Director Director of Water & Sewer Utilities 2
DWR Department of Water Resources 2
ERP Emergency Response Plan 11
HCF Hundred Cubic Feet
Legislature California State Legislature 1
MG Million Gallons 10
SB Senate Bill 1
SCMC City of Santa Clara Municipal Code
SFPUC San Francisco Public Utilities Commission
UWMP Urban Water Management Plan
WSCP Water Shortage Contingency Plan 1
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2025 Water Shortage Contingency Plan
May 2026
Water Shortage Contingency Plan
1.0 INTRODUCTION
This plan presents the City of Santa Clara ’s (City) Water Shortage Contingency Plan (WSCP). The WSCP describes the City’s strategic plan in preparation for and response to water shortages, with a goal to proactively prevent catastrophic service disruptions. It includes water shortage conditions and associated actions that will be implemented in the event of a water supply shortage. As part of the WSCP, the City’s legal authorities, communication protocols, compliance, and enforcement, and monitoring and reporting are included.
A water shortage may occur due to several reasons, such as climate change, drought, and catastrophic events. Drought, regulatory action constraints, and natural and manmade disasters may occur at any time. A water shortage means that the available water supply is insufficient to meet the normally expected customer water use.
In 2018, the California State Legislature (Legislature) enacted two policy bills, (Senate Bill (SB) 606 (Hertzberg) and Assembly Bill (AB) 1668 (Friedman)) (2018 Water Conservation Legislation), to establish a new foundation for drought planning to adapt to climate change and the resulting longer and more intense droughts in California. The 2018 Water Conservation Legislation set new requirements for water shortage contingency planning.
The City’s WSCP is consistent with the 2018 Water Conservation Legislation requirements. The City intends for this WSCP to be an adaptive management plan so that it may assess response action effectiveness and adapt to emergencies and catastrophic events. Refinement procedures and adoption requirements are provided in this plan to allow the City to modify this WSCP outside of the U rban Water Management Plan (UWMP) process.
2.0 WATER SUPPLY RELIABILITY ANALYSIS
The City’s water supply planning analysis and reliability are discussed in the City’s most recent UWMP. A summary of the City’s existing and projected water use is provided in Chapter 4 of the UWMP. Its existing and planned water supplies by source are described in Chapter 6. And its water supply reliability assessment and the drought risk assessment are provided in Chapter 7. The City’s seismic risk assessment and mitigation plan are discussed in Chapter 8.
The City conducts an annual water supply and demand assessment to plan for potential water shortages, as described below in Section 3.0. The analysis associated with this WSCP was developed in the context of the City’s water supply sources and reliability.
3.0 ANNUAL WATER SUPPLY AND DEMAND ASSESSMENT
PROCEDURES
Starting July 1, 2022, California Water Code (CWC) Section 10632.1 require d water suppliers to conduct an Annual Water Supply and Demand Assessment (AWSDA) and submit an Annual Water Shortage Assessment Report to the Department of Water
Water Shortage Contingency Plan
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2025 Water Shortage Contingency Plan
May 2026
Resources (DWR). The assessment is conducted for the current year’s upcoming dry season and the next year, assuming that the next year will be a dry year. This WSCP provides the procedures for the City to conduct its AWSDA. The findings from that assessment will provide information for City’s Annual Water Shortage Assessment Report.
The procedures provided in this section are intended to assist the City in planning for potential, foreseeable shortage in water supplies. These procedures provide the steps the City needs to take that may lead to declaring a water shortage emergency and associated water shortage level (see Section 4.0) and implementation of water shortage response actions (see Section 5.0).
3.1 Decision-Making Process
The City uses the decision -making process described in this section to consistently determine its water supply reliability on an annual basis. The City may adjust and improve this process as needed.
The City’s Water & Sewer Utilities Department is responsible for preparing the City’s AWSDA and Annual Water Shortage Assessment Report and for submitting the Annual Water Shortage Assessment Report to DWR by July 1 of each year. The Water & Sewer Utilities Department will gather key data inputs described in Section 3.2 and conduct the assessment in accordance with Section 3.3. Each year, the City performs the assessment based on the San Francisco Public Utilities Commission ( SFPUC) and Valley Water’s anticipated water deliveries. After completing the AWSDA, City staff presents the Annual Water Shortage Assessment Report to the Water & Sewer Utilities Director for review.
In general, the City will follow the schedule of activities shown in Table 1 for conducting the AWSDA and decision making. These activities are described in further detail in the following subsections. Due to variations in climate and hydrologic conditions, the start and end dates shown in the table are approximate and may be adjusted as needed. The intent of the schedule is to allow shortage response actions to effectively address anticipated water shortage conditions in a timely manner while complying with the State’s reporting requirements.
Table 1. Schedule of Annual Water Supply and Demand Assessment (AWSDA) Activities
Schedule Activities Responsible Party
February Obtain monthly water use data by customer type from Finance Department for previous year.
Water & Sewer
Utility
February
Determine monthly water production data (surface water, potable groundwater, non-potable irrigation groundwater, recycled water) for previous year.
Water & Sewer
Utility
February Obtain population estimates for previous year from DOF (https://www.dof.ca.gov/Forecasting/Demographics/Estimates/) Water & Sewer
Utility
March
Complete analysis for previous year (supply and demand
comparison, hydrologic and regulatory conditions,
infrastructure constraints, etc.).
Water & Sewer
Utility
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2025 Water Shortage Contingency Plan
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Table 1. Schedule of Annual Water Supply and Demand Assessment (AWSDA) Activities
Schedule Activities Responsible Party
March
Calculate projected unconstrained demand for current year and identify/describe projection methods (projected
population growth, etc.).
Water & Sewer
Utility
April
Identify projected hydrologic conditions for current year and obtain any anticipated surface water supply constraints from wholesalers for current year.
Water & Sewer
Utility
April
Determine current conditions of groundwater supply and
groundwater table to anticipate any groundwater supply
constraints for current year.
Water & Sewer
Utility
April
Complete analysis for current year based on a “dry year.” Determine the anticipated monthly water supply reliability for the current year using calculation spreadsheet.
Water & Sewer
Utility
April
Determine if/when water supply shortages will occur and what WSCP stage the shortage will fall into. Determine what (if any) WSCP actions will need to be implemented to mitigate supply shortage.
Water & Sewer
Utility
May Prepare AWSDA presenting the findings and WSCP actions (if any) to be implemented.
Water & Sewer
Utility
May / June Present AWSDA findings to City Council, as needed. Water & Sewer Utility
by July Implement the WSCP actions as approved by City Council (if a water shortage is projected).
Water & Sewer
Utility
July Submit final AWSDA to DWR by July 1. Water & Sewer Utility
Note: Months are approximate and may be adjusted based on climate and hydrologic conditions. July 1 due date is a firm date.
3.1.1 AWSDA Finding: Sufficient Water Supply to Meet Expected Demands If the AWSDA finds that available water supply will be sufficient to meet expected demands for the current year and one subsequent dry year, no further action is required.
City staff will submit the Annual Water Shortage Assessment Report to DWR by July 1 of each year.
3.1.2 AWSDA Finding: Available Water Supply Will Not Meet Demands Should the AWSDA find that available supply will not meet expected demands, the City will coordinate interdepartmentally, with the region’s other water service providers , and with Santa Clara County (County) for the possible proclamation of a n emergency. The Water & Sewer Utilities Director or their designee will present the finalized assessment to City Council, along with recommendations on water shortage condition determination and actions. Recommended actions may include declaration of a water shortage emergency, declaration of a water shortage condition, and water shortage actions.
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2025 Water Shortage Contingency Plan
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Based on the findings of the AWSDA, if a water shortage condition exists, the City Council will adopt a resolution declaring a water shortage emergency and an associated water shortage condition and authorizing water shortage actions. The Water & Sewer Utilities will then prepare the City’s Annual Water Shortage Assessment Report, incorporating the City Council determinations and approved actions. The schedule of decision -making activities is provided in Table 2. The start and end dates and the activities s hown in this table are approximate and may be adjusted as needed.
Table 2. Schedule of Decision-Making Activities if AWSDA Indicates Supply May Not Meet Demands
Schedule Activities Responsible Party
May
Based on finalized determinations of Annual Assessment
regarding water shortage condition and recommended actions, prepare recommendations on water shortage condition
determination and actions.
Water & Sewer
Utility and City
Manager
May Prepare ordinances or resolutions approving determinations and actions.
Water & Sewer
Utility and City
Attorney
May
Coordinate interdepartmentally, with the region’s water service providers, and with the County for the possible proclamation of a local emergency.
Water & Sewer
Utility
May
Based on determinations of the AWSDA, prepare the Annual Water Shortage Assessment Report with recommendations
on water shortage condition. Submit to Water & Sewer Utilities Director.
Water & Sewer
Utility
May
Present finalized determinations and recommendations to City Council, along with ordinances or resolutions approving determinations and actions.
Water & Sewer
Utility and City
Attorney
May / June
Receive presentation of finalized determinations and
recommendations. Make determination of degree of
emergency and act on resolutions that declare a water
shortage emergency condition. Authorize water shortage
response actions for implementation.
City Council
May / June Revise AWSDA to include City Council determinations and approved actions.
Water & Sewer
Utility
June
If a water shortage emergency condition is declared,
implement the WSCP and the water shortage response
actions as approved by City Council.
Water & Sewer
Utility and City
Attorney
July 1 Finalize AWSDA and Annual Water Shortage Assessment Report and submit to DWR (see Table 1).
Water & Sewer
Utility
3.2 Key Data Inputs
The AWSDA is required to evaluate supply and demands for the current year and one subsequent dry year. The following key data inputs will be used to evaluate the City’s water supply reliability.
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Planned water supplies are used as input to the AWSDA for the current year and the following one dry year. The subsequent dry year may be similar to a single dry year as defined in Chapter 7 of the City’s most recently adopted UWMP. In planning for water supplies, the following factors are considered:
• Hydrological conditions
• Regulatory conditions
• Contractual constraints
• Surface water and groundwater quality conditions
• Groundwater well production limitations
• Infrastructure capacity constraints or changes
• Capital improvement projects implementation
• Development Planning
Planned water supply sources and quantities will be described and be reasonably consistent with the supply projections in Chapter 6 ( Normal-Year Water Supply Characterization) of the City’s most recent UWMP. Should the supply sources and projections deviate significantly from the UWMP, the City will provide an explanation addressing the difference.
Planned unconstrained water demands are used as input to the AWSDA for the current year and the following one dry year. Unconstrained water demands are customer demands where no water conservation measures are in effect. In planning for water demands, the following factors are considered:
• Weather conditions
• Water year type
• Population changes (e.g., due to development projects) • Anticipated new demands (e.g., changes to land use)
• Pending policy changes that may impact demands
• Infrastructure operations
Planned water demands types and quantities will be described and be reasonably consistent with the demand projections in Chapter 4 (Water Use Characterization) of the City’s most recent UWMP. Should the demand projections deviate significantly from the UWMP, the City will provide an explanation addressing the difference.
3.3 Assessment Methodology
In preparing the AWSDA, the City will use the following assessment methodology and evaluation criteria to evaluate the City’s water supply reliability for the current year and following one dry year.
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The City will use the AWSDA Reporting Tables workbook provided by DWR as a resource in the WUEdata Portal1 to plan for current year and future year demands. Planned supply and demand inputs described in Section 3.2 will be entered in the spreadsheet in annual increments, or closer time intervals as necessary during water shortage conditions.
Supply and demand will be compared to determine the reliability of the City’s water supply in the current year and the following one dry year. The City’s water supply for the current year and the following dry year will be determined reliable if water supp lies are equivalent to or exceed projected unconstrained water demands. If water supply cannot meet anticipated water demands in the current year or the following dry year, the extent of the water shortage condition will be determined, and the City will pr epare response actions in accordance with this WSCP. If a water shortage is anticipated, t he AWSDA findings will be presented to the City Council, along with recommended actions for City Council consideration.
4.0 STANDARD WATER SHORTAGE LEVELS
To provide a consistent regional and statewide approach to conveying the relative severity of water supply shortage conditions, the 2018 Water Conservation Legislation mandates that water suppliers plan for six standard water shortage levels that correspond to progressive ranges of up to 10, 20, 30, 40, 50 percent, and greater than 50 percent shortages from the normal reliability condition. Each shortage condition should correspond to additional actions water suppliers would implement to meet the severity of the impending shortages. A water shortage is the gap between available supply and projected demands.
Table 3 presents the City’s water shortage level s, which align with the state’s standard levels of water shortage. The City’s water shortage levels apply to both foreseeable and unforeseeable water supply shortage conditions.
1 California Department of Water Resources. “Resources for Urban Water Suppliers.” https://wuedata.water.ca.gov/manage_resources.asp?reportType=urban, last accessed September 22, 2025.
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Table 3. Water Shortage Contingency Plan Levels (DWR Table 8-1)
As described in Section 3.0, the City will conduct an AWSDA to determine its water supply condition for the current year and a subsequent dry year. Preparing the AWSDA helps the City ascertain the need to declare a water shortage emergency and water shortage condition for foreseeable events. In certain cases, the City may need to declare a water shortage emergency due to unforeseen water supply interruptions.
When the City anticipates or identifies that water supplies may not be adequate to meet the normal water supply needs of its customers, the City Council may determine that a water shortage exists and consider a resolution to declare a water shortage emergency and associated level. The shortage level provides direction on shortage response actions, as further described below.
5.0 SHORTAGE RESPONSE ACTIONS
CWC Section 10632(a)(4) requires shortage response actions that align with the defined shortage levels. The City’s shortage response actions consist of a combination of demand reduction, supply augmentation, and operational changes. The City’s suite of response action s depends on the event that precipitates a water shortage level, the Standard
Shortage
Levels
Percent
Shortage Range
Suppliers
Shortage
Levels
Percent
Shortage
Range
1 Up to 10% 1 Up to 10%
2 Up to 20% 2 Up to 20%
3 Up to 30% 3 Up to 30%
4 Up to 40% 4 Up to 40%
5 Up to 50% 5 Up to 50%
6 >50% 6 >50%
Check the box if the Supplier uses the
Standard six levels of water shortage.
Proceed to the next table.
NOTES:
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time of the year the event occurs, the water supply sources available, and the condition of its water system infrastructure.
In general, t he City plans to use a balanced approach, combining demand reduction, supply augmentation, and operational changes to respond to the event and the resulting water shortage level. The City will adapt its implementation of response actions to close the gap b etween water supplies and water demand and meet the water use goals associated with the declared water shortage level.
Meters within the City’s water system allow the City to compare current water demands with demand reduction goals and adjust its shortage response actions accordingly. The City water system is fully equipped with meters which can be read periodically to track the extent of the effectiveness of the City’s response actions.
Water production and water use can be compared to previous periods. This continuous monitoring allows the City to assess water system demands and compare it with its water demand reduction goals. The City may then adjust its shortage response actions as needed to balance demands with available water supplies. For example, the City may intensify its public outreach or more vigorously enforce compliance with water use prohibitions if needed water demand reduction goals are not met for any specific shortage level. Conversely, the City may reduce public outreach frequency or decrease compliance actions if demand reduction goals are exceeded.
The shortage response actions discussed in the following sections may be considered as tools that allow the City to respond to water shortage conditions. Shortage response actions are initiated at the shortage levels shown and continue to be implemented at higher shortage levels. Because the City may continuously monito r and adjust its response actions to reasonably equate demands with available supply, the extent to which the gap between water supplies and water demand will be reduced by implementation of each action is difficult to quantify and is provided as an estimate.
Certain response actions, such as public outreach and enforcement, support the effectiveness of other response actions and do not have a quantifiable effect on their own.
5.1 Demand Reduction Actions
During water shortage conditions, the City plans to reduce demand by implementing the actions shown in Table 4. Demand reduction actions are organized by the triggering water shortage level, and each action includes an estimate of how much its implementation will reduce the shortage gap. For each demand reduction action, Table 4 also indicates if the City uses compliance actions such as penalties, charges, or other enforcement. Demand reduction actions are initiated at the shortage levels shown and will con tinue to be implemented at higher shortage levels.
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Table 4. Demand Reduction Actions (DWR Table 8-3 Retail)
Yes
Volume or
Percentage
Drop down
Shortage Gap Reduction Value
(May be a range) (AF)
1 Expand Public Information
Campaign Percentage
Studies have shown that a
targeted public information
campaign during a drought
can reduce water use by 7 -
8%
-- Yes
1 Increase Water Waste Patrols Percentage 0-1 -- Yes
1 Other Percentage
Boosts the effectiveness of
other methods - not readily
quantifiable
Enforcement of permanent water use restriction
Ordinance (Muni Code 13.15.080) Yes
2 Increase Water Waste Patrols Percentage 0-1 -- Yes
2 Other Percentage
Boosts the effectiveness of
other methods - not readily
quantifiable
Enforcement of permanent water use restriction
Ordinance (Muni Code 13.15.080) Yes
2 Reduce System Water Loss Percentage 0-10 -- Yes
2 Decrease Line Flushing Percentage 0-1 -- Yes
2 Water Features - Restrict water use
for decorative water features, such
as fountains
Percentage 0-1 -- Yes
2 Other Percentage 0-1 Decorative water features must use recirculating water Yes 2 Other - Prohibit use of potable
water for construction and dust
control
Percentage 0-1 -- Yes
2 Other water feature or swimming
pool restriction Percentage 0-1 -- Yes
2 Other Percentage 0-1 New irrigation connections restricted to recycled water Yes 2 Other Percentage 0-1 Irrigation of golf courses restricted to recycled water Yes 2 Landscape - Limit landscape
irrigation to specific days Percentage 5-10 Outdoor watering days may be restricted based on water supply conditions Yes
3 Other Percentage 0-1 Potable water use for decorative water features prohibited Yes
3 Other Percentage 0-1 Irrigation of golf courses except greens and tees restricted, shall use recycled water if available Yes
3 Implement or Modify Drought Rate
Structure or Surcharge Percentage 5-30 -- Yes
3 Increase Frequency of Meter
Reading Percentage 0-5 -- Yes
4 Other Percentage
Boosts the effectiveness of
other methods - not readily
quantifiable
The City shall apportion the City's available supply of water among customers in the most reasonable manner
possible and the rules and regulations for water service may be amended to deal with the water shortage
emergency condition (Muni Code 13.15.140)
Yes
5 Other Percentage
Boosts the effectiveness of
other methods - not readily
quantifiable
The City shall apportion the City's available supply of water among customers in the most reasonable manner
possible and the rules and regulations for water service may be amended to deal with the water shortage
emergency condition (Muni Code 13.15.140)
Yes
6 Other Percentage 0-1 New pool construction and filling prohibited Yes 6 Other Percentage 0-1 New irrigation connections prohibited, recycled water allowed without restriction Yes
Is the Supplier completing this table using the standard six levels? (yes/no) How much is this going to reduce the shortage gap?
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.
Additional Explanation or Reference
(OPTIONAL)
Penalty, Charge,
or Other
Enforcement?
For Retail Suppliers
Only
Drop Down List
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5.2 Additional Mandatory Restrictions
In addition to the demand reduction actions listed in Table 4, the City has other water use restrictions and prohibitions that are enforced at all times listed under Section 1.C of the City’s Potable and Recycled Water System Rules and Regulations. 2 The State also mandates certain prohibitions, and the City will enforce all such requirements.
5.2.1 Water Features and Swimming Pools
Water shortage response would focus on providing sufficient supply to meet health and safety needs for residential customers. Tempering the uses for water features and swimming pools will be based on the severity of the water shortage condition. The relative total water use from these sources would be a consideration for how water features would be restricted during specific water shortage conditions. Water features are a relatively small discretionary use and may be impacted at any time during a triggered water shortage condition.
The City distinguishes special water features, such as decorative fountains and ponds, differently from pools and spas. Special water features are regulated separately. The City’s Potable and Recycled Water System Rules and Regulations Section 1.C requires recirculating water systems to be used for all water features. For decorative water features, recycled water shall be used where available. Covers are required on all new swimming pools and spas.
5.3 Supply Augmentation and Other Actions
The City has approximately 28.8 million gallons (MG) of potable water storage within the City’s service area to manage daily operations and mitigate the effects of a short -term (days) water supply interruption. As part of the City’s operations, the City repair s and replaces water distribution system infrastructure to reduce water system losses. Sources available to the City include an extensive local underground aquifer and imported water supplies delivered by two wholesale water agencies, SFPUC and Valley Water.
In a water shortage emergency, the City may increase groundwater supply or supplies from SFPUC and Valley Water. Supply augmentation and other actions that the City may implement during water supply emergencies are summarized in Table 5.
2 Potable and Recycled Water System Rules and Regulations City of Santa Clara, November 2024, https://www.santaclaraca.gov/our-city/departments-g-z/water-sewer-utilities, last accessed April 15, 2026.
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Table 5. Supply Augmentation and Other Actions (DWR Table 8-2 Retail)
5.4 Locally Appropriate Operational Changes
During a water shortage of any level, the City may elect to implement operational measures to support implementation of the WSCP. This may include hiring temporary workers, reassigning staff, and/or increasing overtime to provide staffing for a range of efforts, such as conducting Water Waste Patrols, implementing the communication protocols, responding to customer service requests, scheduling, and conducting site assessments and consultations, processing incentive and rebate applications, and increasing compliance and enforcement efforts. The City may also elect to increase monitoring of potable water usage , lower water system pressure and limit water main flushing. Operational changes will be considered at each level of water shortage to determine whether and when to implement such measures.
5.5 Emergency Response Plan
The City’s water shortage levels outlined in Section 4.0 apply to both foreseeable and unforeseeable water supply shortage conditions, including catastrophic water shortage conditions.
Yes
Volume or
Percentage
Drop down
Shortage Gap
Reduction Value
(May be a range)
(AF)
1 Other Actions (describe) Percentage 10
Increase groundwater use if needed,
combined with demand reduction
actions
2 Other Actions (describe) Percentage 20
Increase groundwater use, SFPUC, and/or
Valley Water to supplement supply that
is deficient, combined with demand
reduction actions
3 Other Actions (describe) Percentage 30
Increase groundwater use, SFPUC, and/or
Valley Water to supplement supply that
is deficient, combined with demand
reduction actions
4 Other Actions (describe) Percentage 40
Increase groundwater use, SFPUC, and/or
Valley Water to supplement supply that
is deficient, combined with demand
reduction actions
5 Other Actions (describe) Percentage 50
Increase groundwater use, SFPUC, and/or
Valley Water to supplement supply that
is deficient, combined with demand
reduction actions
6 Other Actions (describe) Percentage >50
Increase groundwater use, SFPUC, and/or
Valley Water to supplement supply that
is deficient, combined with demand
Is the Supplier completing this table using the standard six levels? (yes/no) How much is this going to reduce the
shortage gap?
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
Additional Explanation or Reference
(OPTIONAL)
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The City’s Emergency Response Plan (ERP) addresses catastrophic water shortage conditions. The ERP outlines response procedures associated with unforeseeable incidents such as a regional power outage , earthquake, infrastructure failure, and other events. More specifically, it addresses responses for water system losses including current water emergency interconnections, water demands under earthquake emergency conditions and non-earthquake emergencies. The ERP also identifies seven categories of response and the criteria that triggers that specific response to occur.
The communication procedures are also outlined in the ERP. In response to a drought, the ERP outlines the procedures the City is recommended to follow which includes: initial actions, continuous assessment and response procedures and after action monitoring and reporting. Steps for deactivation and demobilization of activated triggers and response actions are also identified to facilitate recovery procedures and return to normal operation. In addition, the effectiveness of the ERP is evaluated by the Depart ment staff on a periodic basis. This is to ensure that procedures and practices developed in the ERP are adequate and implemented properly . To protect the security of the City’s water system, the ERP is retained by the City as a confidential document.
6.0 COMMUNICATION PROTOCOLS
In the event of a water shortage, the City must inform its customers, the general public and interested parties, and local, regional, and state entities. Communication protocols for foreseeable and unforeseeable events are provided in this section. In any event, timely and effective communication must occur for a ppropriate response to the event.
City staff are provided with City email accounts and cell phones to communicate internally and externally.
6.1 Communication for Foreseeable Events
Water shortage may be foreseeable when the City conducts its AWSDA as described in Section 3.0. When the City determines the potential of a water shortage event, the City Council may determine and declare a water shortage emergency. The City will hold a duly noticed public meeting to present the current or predicted shortage. At the public meeting, the City Council will determine if a water shortage emergency condition exists and the degree of the emergency. The City Council will cons ider the shortage response actions triggered or anticipated to be triggered by the shortage level. As necessary, the City Council will act on the water shortage emergency declaration, associated water shortage level, and shortage response actions.
The City will follow the communication protocols and procedures below and may trigger any of them at any water shortage level:
1. If a water shortage emergency is anticipated, the City will coordinate interdepartmentally, with the region’s water service providers, and with the County for the possible proclamation of a local emergency.
2. The City will issue a public notice for a City Council meeting during which the AWSDA findings and recommendations for a water shortage emergency and shortage response actions are presented.
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3. The City will communicate actions to customers, the general public, and interested parties through a combination of bill stuffers and newsletters, website, press releases, and social media posts.
4. The City will communicate actions to relevant local, regional, and state officials and entities primarily through email correspondence.
6.2 Communication for Unforeseeable Events
A water shortage may also occur during unforeseeable events such as earthquakes, fires, infrastructure failures, civil unrest, and other catastrophic events. The City’s ERP provides specific communication protocols and procedures to convey actions during these events.
The City may trigger these communication protocols, depending on the event. In general, communications and notifications will proceed along the identified chain of command. All City staff are provided their communication responsibilities. The ERP also provides a list of relevant contacts to notify at the local, regional, and state level.
7.0 COMPLIANCE AND ENFORCEMENT
This section describes how the City will ensure compliance with and enforcement of provisions of this WSCP. The City’s procedures include protocols for treatment of violations and actions associated with more egregious levels of violation. The procedures include appeal and exemption processes.
7.1 Compliance and Enforcement Procedures
When a water shortage is anticipated, the City Council will adopt a resolution declaring a water shortage emergency condition and the regulations and restrictions that should be enforced in response to the declared water shortage level.
The City is metered system -wide, at production facilities and at each customer connection. Thus, water use can be quantified and compared to determine users’ extent of compliance to water reduction requirements. The City may also become aware of non-compliance through water waste reporting by the general public, the City’s dedicated water waste hotline, City staff inspections, and/or manual review of customer use data.
Upon receiving a water waste complaint, City staff will investigate the offending site’s water use history and make site visits to determine the cause of the waste. City staff will then reach out to the site to educate them on the City’s water waste policies and help them get into compliance. In addition, City staff uses this opportunity to further educate businesses and residents on current water conservation programs and what opportunities there may be to increase their water efficiency. While outreach an d education typically brings most water wasters into compliance, the City does retain the ability to levy fines of up to $1,000 and the installation of a flow restrictor to frequent offenders, per the City of Santa Clara Municipal Code ( SCMC) 13.15.220.
The Director of Water & Sewer Utilities or their designee is responsible for enforcement and penalties. Water users or property owners can appeal the notice of violation or the
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administrative fee by submitting a written request for appeal to the Director of Water & Sewer Utilities, per the City’s Potable and Recycled Water System Rules and Regulations.
8.0 LEGAL AUTHORITIES
SCMC Chapter 13.15 supports the City’s ongoing water use restrictions, including provisions for enforcement. The SCMC does not contain provisions for additional restrictions on water use during water shortages. Should a water shortage occur, the City would need to adopt an emergency ordinance to restrict water use as needed. The emergency ordinance would support the City’s water shortage contingency actions, including regulations and restrictions to be enacted in event of a water shortage.
At the time of a water shortage emergency, the City Council will, by resolution, declare a state of water shortage emergency and authorize implementation of the WSCP. A water shortage emergency declaration will be in effect upon proper findings made by the City Council and remain in effect until the City Council finds and declares by resolution that the water shortage emergency condition has abated, has changed in degree, or no longer exists.
When a water shortage is determined, the City will coordinate interdepartmentally, with the region’s water service providers, and with the County for the possible proclamation of a local emergency in accordance with under California Government Code, California Emergency Services Act (Article 2, Section 8558).
In a duly noticed meeting, the City Council will determine whether a water shortage emergency condition exists and, if so, the degree of the emergency and what regulations and restrictions should be enforced in response to the shortage. The City shall declare a water shortage emergency in accordance with CWC Chapter 3 of Division 1.
California Water Code Division 1, Section 350:
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.
The water shortage emergency declaration triggers communication protocols described in Section 6.0 and compliance and enforcement actions described in Section 7.0.
9.0 FINANCIAL CONSEQUENCES OF WSCP
Because the City bills its customers in part per unit volume of water consumed, the City may experience a reduction in revenue upon implementation of water shortage levels.
The City policy is to maintain adequate water fund reserves in the event water shortage and subsequent demand reduction measures impact the City’s revenue.
To mitigate the financial impacts of reduced water sales during a drought, the City Council has the authority to impose a drought surcharge on water rates. This surcharge could be
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a flat fee per hundred cubic feet (HCF) that is intended to provide the City’s water utility with dependable revenues when water use reduction plans are in effect. The City has traditionally used a “postage stamp” rate for all water sales. With reduction in sales, the fixed costs will remain, imposing a loss on the utility (expenses in excess of revenues).
An advantage to the drought surcharge is that it is designed and set to allow sufficient revenue to meet all costs for the utility while also achieving conservation. The water utility also has reserves that it has used in the past as a rate stabilization fund. These reserves are being used to help reduce the rate impact from ever -increasing wholesale costs and the lower water sales due to the recent drought and slow recovery of water use.
Additionally, the Utility is currently developing a long range financial and rate stabilization plan. The water utility’s reserves are intended to be at the level that is sufficient to cover short-term loss of revenues due to a drought or other short-term catastrophic loss of sales.
Reserves are adequately funded as part of the rate setting process.
10.0 MONITORING AND REPORTING
The City water system is fully metered, from its water supply sources to individual customer meters. These meters may be used as monitoring tools for compliance and reporting purposes. The City’s water system is fully set up for automated meter reading (AMR); the City plans to upgrade the entire system to AMI as soon as reasonably possible. AMI would allow the City to monitor customer water usage in real time as necessary for assessing compliance with demand reduction actions and helping customers achieve reduction goals.
If reduction goals are not met through implementation of the WSCP (during any water shortage level), the Director of Water & Sewer Utilities ( Director) will notify the City Council, and more stringent action will be taken. Additionally, if it is determined that this WSCP requires refinements to achieve reduction targets, the City will revise the WSCP according to the procedures discussed in Section 11.0 and then adopt it and make it available as discussed in Section 12.0.
11.0 WSCP REFINEMENT PROCEDURES
This WSCP is an adaptive management plan. It is subject to refinements as needed to ensure that the City’s shortage response actions and mitigation strategies are effective and produce the desired results. Based on monitoring described in Section 10.0 and the need for compliance and enforcement actions described in Section 7.0, the City may adjust its response actions and may modify its WSCP. When a revised WSCP is proposed, the revised WSCP will undergo the process described in Section 12.0 for adoption by the City Council and distribution to the County, its customers, and the general public.
Feedback from City staff and the public is important in refining or incorporating new actions. The City seeks input from staff who interface with customers to gauge the effectiveness of its response actions and for response action ideas. The City seeks input from its customers and the general public through its website and through regularly scheduled City Council meetings.
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Customer water meter data may be evaluated for each customer sector or each individual customer. The City tracks water use violations and may evaluate their frequency to determine restrictions that customers may not be able to meet. This evaluation may also show water demand reduction actions that customers may effectively implement.
12.0 PLAN ADOPTION, SUBMITTAL, AND AVAILABILITY
The WSCP may be adopted concurrently with the City’s UWMP, by separate resolution , and may be revised and adopted at any time by the City. Prior to adoption, a duly noticed public hearing is conducted. A hard copy and electronic copy of the WSCP will be submitted to DWR within 30 days of adoption.
No later than 30 days after submittal to DWR, copies of the WSCP will be available at the City’s offices. A copy will also be provided to the County. An electronic copy of this WSCP will also be available for public review and download on the City’s website.
UWMP and WSCP Adoption Resolutions
Not included with this submittal.
Appendix H