2026-05-12; Municipal Water District; 10; Public hearing for approval of the 2025 Urban Water Management Plan and Water Shortage Contingency Plan — Carlsbad City Council, May 12, 2026 (part 1 of 4)

CA Review TL
Meeting Date: May 12, 2026
To: President and Board Members
From: Geoff Patnoe, Executive Manager
Staff Contacts: Keri Martinez, District Engineer
[email protected], 442-200-7376
Dave Padilla, Assistant General Manager
[email protected], 442-339-2356
Subject: Public hearing for approval of the 2025 Urban Water Management Plan and Water Shortage Contingency Plan
Districts: All
Reco
mmended Actions
1) Hold a public hearing; and
2) Adopt a resolution adopting t he 2025 Urban Water Management Plan and the Water Shortage Contingency Plan and authorizing submittal to the California Department of Water Resources; or
3) Adopt a resolution adopting the 2025 Urban Water Management Plan and the Water Shortage Contingency Plan and delegating authority to the Executive Manager to approve revisions to the plans and authorizing submittal to the California Department of Water Resources.

Executive Summa ry
The California Department of Water Resources requires all urban water suppliers in the state, including the Carlsbad Municipal Water District, to have an urban water management plan that also contains a water shortage contingency plan.

State law requires these plans to be updated at least once every five years on or before July 1, in years ending in six and one, incorporating updated and new information from the five years preceding each update. The CMWD Board adopted the 2020 Urban Water Management Plan on June 8, 2021. State law calls for the board to adopt the 2025 plan through a public hearing before July 1, 2026.

Urban water management plans must comply with the Urban Water Management Planning Act, codified in Sections 10610 through 10657 of the California Water Code. The 2025 Urban Water Management Plan and the water shortage contingency plan (Section 8 of the plan) meet the requirements of state law and include an analysis of long-term water demand and supply planning for the CMWD.

May 12, 2026
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Docusign Envelope ID: B59C0B04-D741-436B-B590-41CAEE92C366 Staff request that the CMWD Board adopt a resolution approving the 2025 Management Plan or, if revisions to the plan are required as a result of public hearing comments, that the board adopt a resolution approving the 2025 Management Plan and delegating authority to the Executive Manager to approve revisions to the plan as directed by the board.

Explanation & Analysis
Water demand
The water demand projections presented in the 2025 Management Plan are based on the CMWD’s monthly consumption records by customer type from 2014 through 2025, annual system water loss audit reports and the City of Carlsbad local housing units forecast. The primary water uses in the CMWD’s service area are residential, commercial, industrial, agricultural and irrigation. The table below summarizes the historical and current water use in acre-feet1 per year.

Historical and current water use
Water use type 2005 2010 2015 2020 2025
Single family residential 9,009 7,965 6,995 7,695 7,254 Multi-family residential 1,963 1,769 1,621 1,762 1,862
Commercial 3,695 2,886 2,775 2,098 2,636
Industrial/governmental - - 6 19 38
Institutional 162 122 105 102 122
Agricultural 716 374 181 162 145
Landscape - potable water 4,214 1,914 1,583 1,528 1,502 Water loss and unbilled 1,373 1,094 968 509 903
Landscape - recycled water 1,966 3,500 3,793 3,765 3,708 TOTAL 23,098 19,624 18,027 17,640 18,170
Based on this historical use, the following table summarizes the CMWD’s baseline demands, recycled water use, and overall drinking water demand projections, also in acre feet per year.

Summary of projected demands
Water use type 2025 2030 2035 2040 2045 2050
Single family residential 7,254 7,897 8,716 8,716 8,716 8,716 Multi-family residential 1,862 2,128 2,464 2,464 2,464 2,464 Commercial 2,636 2,913 3,066 3,226 3,395 3,573
Industrial/governmental 38 38 40 42 44 46
Institutional 122 145 152 160 169 177
Agricultural 145 163 163 163 163 163
Landscape - potable water 1,502 1,227 1,136 1,052 974 902 Water loss and unbilled 903 404 437 440 443 446
Landscape - recycled water 3,708 3,898 4,218 4,218 4,218 4,218 TOTAL 18,170 18,812 20,393 20,482 20,586 20,706
1 One acre-foot (A F) equals enough water to cover one acre one-foot deep. It is 43,560 cubic feet, or 325,851 gallons of water.

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Docusign Envelope ID: B59C0B04-D741-436B-B590-41CAEE92C366 The chart below shows these past and future water uses by use sector. Recycled water is included to provide an overall summary of the CMWD’s water supply. Population illustrates how water demand changes relative to population growth.

CMWD’s historical, current, and projected water use
Futu
re population and growth trends are essential to predict the CMWD’s future water demands and water use characteristics. The population projections for the CMWD service area are presented in the table below and reflect regional population estimates from the San Diego Association of Governments (SANDAG), the U.S. Census Bureau American Community Survey and local planning data coordinated with the City of Carlsbad’s Planning Division.

The city’s local planning data was used because it reflects sooner and more rapidly changing local development conditions. It’s expected that the population and housing inventory in Carlsbad is and will continue to increase at a faster rate than previously anticipated, eventually stabilizing in 2035.

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Docusign Envelope ID: B59C0B04-D741-436B-B590-41CAEE92C366 This trend is driven by recent state regulations (e.g., Senate Bills 166 and 3302) that require local jurisdictions to plan to increase their housing availability in an attempt to increase available, affordable housing to moderate the high cost of living in California. The city anticipates that it will be fully developed, or built out, by 2035, and, after 2035, that the number of housing units will remain relatively constant through the 2050 planning horizon.

CMWD population projections comparison
Population data 2025 2030 2035 2040 2045 2050
SANDAG 101,040 104,719 105,640 105,124 104,083 103,033
American Community
Survey 91,472 93,533 95,682 97,859 100,085 102,363
Local planning data2 96,371 106,031 119,616 119,616 119,616 119,616 2 Local planning data were used for population projections While population is expected to increase, the CMWD expects ongoing water conservation and increased recycled water use will reduce drinking water demands on a gallon-per-person-per- day estimate. The Department of Water Resources and the State Water Resources Control Board recently implemented reporting requirements known as “Making Conservation a California Way of Life,” in keeping with Assembly Bill 1668 and Senate Bill 606. The CMWD has and will continue to make strides to reduce water demands by promoting water conservation programs.

Water supply
The 2025 Urban water Management Plan demonstrates that the CMWD has ample water supply to meet demand through the defined planning timeframe of 2050.

The CMWD purchases potable water from the San Diego County Water Authority, which sells water to the CMWD and 21 other retail water agencies. As a regional wholesaler in Southern California, the Water Authority is uniquely prepared for multiple years of drought due to three decades of investments in supply reliability because it receives its water supplies from the Colorado River, Sacramento-San Joaquin Delta and the Carlsbad desalination plant, and purchases water from the Metropolitan Water District of Southern California.

The CWMD participates in the Water Authority’s efforts to reduce reliance on water from the Sacramento-San Joaquin Delta. Additionally, the CMWD has a reliable local supply of potable water from the Carlsbad Desalination Plant and a recycled water supply from the Carlsbad Water Recycling Facility.
2 California Senate Bill 166 strengthens the state’s Housing Accountability Act by requiring cities and counties to have sufficient sites zoned and available to meet their housing obligations at all times. Senate Bill 330 restricts local governments’ ability to reduce housing capacity, streamlines parts of the approval process and restricts the number of public hearings to prevent delays in housing development

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Docusign Envelope ID: B59C0B04-D741-436B-B590-41CAEE92C366 The table below summarizes the current and projected water supplies for the CMWD service area.

Summary of current and projected supplies (in acre feet per year) Source 2025 2030 2035 2040 2045 2050
Water Authority purchases 11,962 12,414 13,675 13,764 13,868 13,988 Seawater desalination 2,500 2,500 2,500 2,500 2,500 2,500 Recycled water 3,708 3,898 4,218 4,218 4,218 4,218
Total water supplies 18,170 18,812 20,393 20,482 20,586 20,706 Note: Recycled water supplies include purchases from the Vallecitos Water District and supplies from the Carlsbad Water Recycling Facility. The desalination water supply contract with the county Water Authority for 2,500 acre feet per year is expected to be renewed in 2046.

Reliability
The city’s arid climate, limited local supplies, and growing population make water shortage planning an important component of supply management, especially in light of the region’s history with severe drought and the potential for increased frequency, intensity and duration of droughts due to climate change.

A key requirement in the Management Plan is a future supply reliability analysis that demonstrates the supply-demand balance in normal, single-dry and multiple-dry year rainfall conditions. Consistent with the county Water Authority’s 2025 Management Plan, the CMWD estimates that water demand will increase as weather gets hotter and drier during the single- dry year and multiple-dry year scenarios. Recycled water supplies and the CMWD’s local desalinated water supplies are estimated to remain steady in all hydrologic scenarios because they are both drought-proof supplies.

Changes in demand have a direct impact on how much water the CMWD purchases from the Water Authority. The Water Authority. and the CMWD have coordinated on the district’s Urban Water Management Plan and, based on the results of a reliability analysis, forecast that water supply will be adequate to meet demand during a drought. In the highly unlikely event that the Water Authority cannot fully meet the CMWD’s water demands, the CMWD would receive advance notice and implement the appropriate water‑saving measures outlined in its Water Shortage Contingency Plan to reliably serve customers through both short‑ and long‑term drought conditions.

Fiscal Analysis
Adopting the Urban Water Management Plan has no financial impact, although the projects and policies that may develop from its findings may have financial impact. These impacts will be disclosed and brought before the CMWD Board for consideration as the projects or policies are implemented.

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Docusign Envelope ID: B59C0B04-D741-436B-B590-41CAEE92C366 Options
Option 1: Staff request that the CMWD Board adopt a resolution adopting the 2025 Urban Water Management Plan and Water Shortage Contingency Plan attached as Attachment A to Exhibit 1.

Option 2: If revisions to the plans are required as a result of public hearing comments, staff recommend the CMWD Board adopt a resolution adopting the 2025 Management Plan in Exhibit 2 and delegating authority to the Executive Manger to approve revisions to the plans limited to those the Board directs the Executive Manager or designee to make in response to public input at the public hearing or otherwise.

Next Steps
With its adoption, the Executive Manager or designee will submit the final plans to the Department of Water Resources by the July 1, 2026, deadline.

If the CMWD Board requests revisions to incorporate public comments and selects Option 2, staff will revise the plan(s) as directed and submit to the Executive Manager for approval of the final versions prior to submitting to the DWR by the deadline.

The final adopted plans will be made available on the CMWD website and retained on file at the CMWD office.

Environmental Evaluation
The proposed action is not a “project” as defined by California Environmental Quality Act, or CEQA, Section 21065 and CEQA Guidelines Section 15378(a) and does not require environmental review under CEQA Guidelines Section 15282(v) because it involves the preparation and adoption of the Urban Water Management Plan and Water Shortage Contingency Plan pursuant to the provisions of Section 10652 of the Water Code.

Exhibits

1. CMWD Board resolution, Option 1

2. CMWD Board resolution, Option 2
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Docusign Envelope ID: B59C0B04-D741-436B-B590-41CAEE92C366 Exhibit 1
RESOLUTION NO. 1804 .

A RESOL

UTION OF THE BOARD OF DIRECTORS OF THE CARLSBAD
MUNICIPAL WATER DISTRICT , ADOPTING THE 2025 URBAN WATER

MANAGEMENT PLAN AND THE WATER SHORTAGE CONTINGENCY PLAN

AND AUTHORIZ ING SUBMITTAL TO THE CALIFORNIA DEPARTMENT OF

WATER RESOURCES
WHERE
AS, the 20 25 Urban Water Management Plan has been prepared by the Carlsbad Municipal Water District, or CMWD, in conformance with the Urban Water Management Planning Act contained in California Water Code Section 10610 et. seq.; and WHEREAS, Water Code Section 10632 requires the CMWD to prepare and adopt a Water Shortage Contingency Plan as part of its Urban Water Management Plan; and WHEREAS, the CMWD’s Water Shortage Contingency Plan is a portion of the 2025 Urban Water Management Plan and functions as a stand-alone document that can be amended as needed without amending the Urban Water Management Plan; and
WHEREAS, on March 9, 2026, in conformance with the California Water Code Section 10621, the CMWD mailed a 60 -day public hearing notification letter to all city and county agencies to which the CMWD provides water supplies; and
WHEREAS, Section 10642 of the California Water Code requires that prior to adopting an Urban Water Management Plan and/or a Water Shortage Contingency Plan, an urban water supplier shall make the plan s available for public inspection and hold a public hearing to receive public comment regarding the plan(s); and
WHEREAS, on March 11, 2026, the CMWD made copies of the Urban Water Management Plan, including the Water Shortage Contingency Plan, available for review on the City of Carlsbad's website at carlsbadca.gov; and
WHEREAS, a notice of public hearing was published via a newspaper ad on April 28, 2026, and May 5, 2026; and
WHEREAS, a public hearing was held on May 12, 2026, to receive public comment regarding the 2025 Urban Water Management Plan, including the Water Shortage Contingency Plan.

NOW, THEREFORE, BE IT RESOLVED by the Carlsbad Municipal Water District Board of Directors of the City of Carlsbad, California, as follows:

1. That the above recitations are true and correct.

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Docusign Envelope ID: B59C0B04-D741-436B-B590-41CAEE92C366

2. That the CMWD Board has determined that the proposed action is not a “project” as defined by California Environmental Quality Act, or CEQA , Section 21065 and CEQA Guidelines Section 15378(a) and does not require environmental review under CEQA Guidelines Section 15282(v) because it involves the preparation and adoption of the Urban Water Management Plan and Water Shortage Contingency Plan pursuant to the provision of Section 10652 of the Water Code.

3. That the Board adopts the 2025 Urban Water Management Plan and the Water Shortage Contingency Plan, attached hereto as Attachment A , and authorizes the Executive Manager or designee to submit them to the California Department of Water Resources.

PASSED, APPROVED AND ADOPTED at a Special Meeting of the Board of Directors of the Carlsbad Municipal Water District of the City of Carlsbad on the 12th day of May, 2026, b y the following vote, to wit:

AYES: Blackburn, Bhat-Patel, Acosta, Burkholder, Shin.

NAYS: None.

ABSTAIN None.

ABSENT: None.
__________________
________________
KEITH BLACKBURN, President
___________________________
_______
SHERRY FREISINGER, Secretary
(SEAL)
May 12, 2026
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Docusign Envelope ID: B59C0B04-D741-436B-B590-41CAEE92C366

Carlsbad Municipal Water District
2025 Urban Water Management Plan Update
Attachment A
May 12, 2026
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Docusign Envelope ID: B59C0B04-D741-436B-B590-41CAEE92C366 2025 Urban Water Management Plan
Prepared by:

Carlsbad Municipal Water District
5950 El Camino Real
Carlsbad, CA 92008
www.carlsbadca.gov
Wi
th assistance from:

Woodard & Curran
9665 Chesapeake Drive
Suite 320
San Diego, CA 92123
May 2026
May 12, 2026
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Docusign Envelope ID: B59C0B04-D741-436B-B590-41CAEE92C366 Carlsbad Municipal Water District
2025 Urban Water Management Plan May 2026
Table of Contents i

TABLE OF CONTENTS
SECTION PAGE NO.

EXECUTIVE SUMMARY .................................................................................................ES-1

1. INTRODUCTION AND OVERVIEW ....................................................................... 1-1

1.1 B
ackground and Purpose ............................................................................................ 1-1

1.2 Cal
ifornia Urban Water Management Planning Act .......................................... 1-1

1.3 R
elation to Other Planning Efforts ........................................................................... 1-2

1.4 L
ay Description ............................................................................................................... 1-4

1.5 O
rganization of the Urban Water Management Plan ...................................... 1-4

2. PL
AN PREPARATION ............................................................................................ 2-1

2.1 P
lan Preparation and Implementation ................................................................... 2-1

2.2 Co
ordination and Outreach ....................................................................................... 2-2

2.3 P
ublic Participation ....................................................................................................... 2-4

2.4 P
lan Organization .......................................................................................................... 2-5

3. SYS
TEM DESCRIPTION .......................................................................................... 3-1

3.1 D
escription of Service Area ........................................................................................ 3-1

3.1. 1 Agency Organizational Structure ................................................................... 3-2

3.1. 2 Service Area Climate ........................................................................................... 3-4

3.1. 3 Land Uses Within the Service Area ................................................................ 3-5

3.1. 4 Population and Demographics ....................................................................... 3-6

3.3 D
escription of Water System ................................................................................... 3-11

3.4 W
ater System Background ....................................................................................... 3-12

3.5 Cl
imate Change ............................................................................................................ 3-16

3.5. 1 Climate Action Plan and Energy ................................................................... 3-16

3.5. 2 Climate Change Vulnerability Analysis....................................................... 3-17

4. WAT
ER USE ............................................................................................................ 4-1

4.1 P
ast and Current Water Use ....................................................................................... 4-1

4.1. 1 Single-Family Residential and Multi-Family Residential ........................ 4-2

4.1. 2 Agricultural ............................................................................................................. 4-2

4.1. 3 Commercial/ Industrial/ Institutional/ Government ................................ 4-4

4.1. 4 Tourism and Temporary Residents................................................................ 4-4

4.1. 5 Landscape ............................................................................................................... 4-5

4.1. 6 Additional Water Uses ....................................................................................... 4-6

4.1. 7 Sales to Other Agencies .................................................................................... 4-6 May 12, 2026
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Table of Contents ii

4.1.8 Distribution System Losses .............................................................................. 4-7

4.2 P
rojected Water Use ................................................................................................... 4-10

4.2. 1 Climate Change Effects on Water Use ....................................................... 4-12

4.2. 2 Future Conservation Savings ......................................................................... 4-12

4.2. 3 Water Use for Lower Income Households ................................................ 4-14

4.2. 4 Projected Total Water Use and Demand Provided to Wholesaler ... 4-15

5. SB X7-7
TARGETS AND REPORTING ................................................................... 5-1

5.1 O
verview ........................................................................................................................... 5-1

5.2 W
ater Use and Compliance ........................................................................................ 5-2

6. WAT
ER SUPPLY ..................................................................................................... 6-1

6.1 W
ater Supply Characterization ................................................................................. 6-1

6.2 P
urchased or Imported Water ................................................................................... 6-3

6.2. 1 Metropolitan Water District of Southern California (MWD) ................ 6-3

6.2. 2 San Diego County Water Authority (SDCWA) ........................................... 6-3

6.3 D
esalinated Water ......................................................................................................... 6-4

6.4 W
astewater and Recycled Water ............................................................................. 6-5

6.4. 1 Recycled Water Coordination ......................................................................... 6-6

6.4. 2 Wastewater Treatment and Collection Facilities ...................................... 6-6

6.4. 3 Recycled Water Master Plan .......................................................................... 6-11

6.4. 4 Recycled Water Use .......................................................................................... 6-11

6.4. 5 Potential and Projected Recycled Water Use .......................................... 6-14

6.4. 6 Methods to Encourage Recycled Water Use ........................................... 6-14

6.5 L
ocal Groundwater and Local Surface Water .................................................... 6-15

6.6 S
upply from Storage ................................................................................................... 6-18

6.7 Stormwater ..................................................................................................................... 6-19

6.8 E
xchanges and Transfers ........................................................................................... 6-19

6.9 P
rojected Water Projects ........................................................................................... 6-19

6.9. 1 Summary of Existing and Planned Sources of Water ........................... 6-23

6.10 S
pecial Considerations ............................................................................................... 6-25

6.10. 1 Climate Change Impacts ................................................................................. 6-25

6.10. 2 Regulatory Conditions ..................................................................................... 6-25

6.10. 3 Other Locally Applicable Criteria .................................................................. 6-26

6.11 Ene
rgy Intensity ............................................................................................................ 6-27

7. WAT
ER SUPPLY RELIABILITY AND DROUGHT RISK ASSESSMENT ................. 7-1

7.1 C
onstraints on Water Resources .............................................................................. 7-1

7.1. 1 SDCWA Supply Constraints and Reliability Actions ................................ 7-2

7.1. 2 CMWD Local Supply Constraints and Reliability Actions ...................... 7-3 May 12, 2026
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7.2 Water Service Reliability Assessment ..................................................................... 7-5

7.2. 1 Year Type Characterization .............................................................................. 7-5

7.2. 1.1 Water Service Reliability – Normal Year .......................................... 7-6

7.2. 1.2 Water Service Reliability – Single Dry Year .................................... 7-8

7.2. 1.3 Water Service Reliability – Five Consecutive Dry Years ............. 7-9

7.2. 2 Management Tools and Options ................................................................. 7-11

7.3 D
rought Risk Assessment ......................................................................................... 7-12

7.3. 1 Data and Methodology ................................................................................... 7-12

7.3. 2 Determination of Reliability ........................................................................... 7-13

8. WAT
ER SHORTAGE CONTINGENCY PLAN ......................................................... 8-1

8.1 W
ater Supply Reliability Analysis ............................................................................. 8-1

8.1. 1 Legal Authorities .................................................................................................. 8-2

8.1. 2 Plan Adoption, Submittal and Availability .................................................. 8-2

8.2 A
nnual Water Supply and Demand Assessment Procedures ........................ 8-2

8.2. 1 Decision-Making Process .................................................................................. 8-3

8.2. 2 Water Supply Projection: Data Inputs and Methodology ..................... 8-4

8.2. 3 Planned Water Use for Current Year and Subsequent Dry Year: Data Inputs and Methodology .................................................................................. 8-4

8.2. 4 Infrastructure Considerations: Data Inputs and Methodology ........... 8-5

8.2. 5 Evaluation Criteria: Data Inputs and Methodology ................................. 8-5

8.3 S
ix Standard Water Shortage Stages and Shortage Response Actions ..... 8-6

8.4 Catas
trophic Supply Interruption ........................................................................... 8-12

8.4. 1 Seismic Risk Assessment and Mitigation Plan ........................................ 8-12

8.4. 2 CMWD Emergency Storage of Water Policy ............................................ 8-13

8.5 C
ommunication Protocols ........................................................................................ 8-14

8.5. 1 Coordination ........................................................................................................ 8-14

8.5. 2 Communication Objectives ............................................................................ 8-15

8.5. 3 Communication Protocol for Current Predicted Shortage ................. 8-15

8.5. 4 Communication Protocol for Triggered or Anticipated to be Triggered Shortage Response Action ............................................................................. 8-17

8.5. 5 Catastrophic Communications ...................................................................... 8-17

8.6 C
ompliance and Enforcement ................................................................................. 8-17

8.7 W
SCP Revenue and Expenditure Impacts ........................................................... 8-18

8.8 W
SCP Monitoring and Reporting .......................................................................... 8-20

8.9 W
SCP Refinement Procedures ................................................................................ 8-22

8.10 S
pecial Water Feature Distinction .......................................................................... 8-22

8.11 D
etermination of Reliability ..................................................................................... 8-23 May 12, 2026
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9. DEMAND MANAGEMENT MEASURES ................................................................ 9-1

9. 1 Current Demand Management Measures ............................................................ 9-1

9. 1.1 Water Waste Prevention Ordinances............................................................ 9-1

9. 1.2 Metering .................................................................................................................. 9-2

9. 1.3 Conservation Pricing ........................................................................................... 9-2

9. 1.4 Public Education and Outreach ...................................................................... 9-3

9. 1.5 Programs to Assess and Manage Distribution System Real Loss ...... 9-8

9. 1.6 Water Conservation Program Coordination and Staffing Support ... 9-8

9. 2 DMM Activity ................................................................................................................... 9-8

9. 3 Future DMM Implementation ................................................................................... 9-9

10. P
LAN ADOPTION, SUBMITTAL, AND IMPLEMENTATION ............................. 10-1

10. 1 Plan Review and Notification Process .................................................................. 10-1

10. 2 Plan Adoption and Submittal Process .................................................................. 10-2

10. 3 Plan Implementation .................................................................................................. 10-2

10. 4 WSCP Adoption, Submittal and Availability ....................................................... 10-2

11. R
EFERENCES ......................................................................................................... 11-1 May 12, 2026
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Table of Contents v
TABLES
Table ES-1: Organizational Overview of the 2025 UWMP
Tab
le ES-2: Summary of Current and Projected Supplies (AFY) Tab
le ES-3: SBx7-7 Baselines and Targets for CMWD
Tab
le ES-4: Summary of Projected Demands
Tab
le 2-1: Public Water System
Tab
le 2-2: Plan Identification
Tab
le 2-3: Supplier Identification
Tab
le 2-4: Water Supplier Information Exchange
Tab
le 2-5: Coordination with Agencies
Tab
le 3-1: Land Use Classification Within the City of Carlsbad Tab
le 3-2: CMWD’s Service Area Population – Current and Projected Tab
le 3-3: CMWD Growth Population Comparison
Tab
le 3-4: Wastewater and Water GHG Reduction Measures
Tab
le 3-5: Potential Impacts of Climate Change in Carlsbad Tab
le 3-6: Prioritized Climate Change Vulnerability Issues for Carlsbad Tab
le 3-7: Existing Programs, Plans, and Policies
Tab
le 4-1: Historical and Current Water Use (AFY) (2005-2025) Tab
le 4-2: 2025Actual Total Uses for Potable and Non-Potable Water (AFY) Tab
le 4-3: Reported Water Loss (2020 – 2025)
Tab
le 4-4: Retail Water Loss Audit Reporting
Tab
le 4-5: Progress Toward 2028 Water Loss Standard
Tab
le 4-6: Growth Rate Calculations for Each Customer Class Tab
le 4-7: Inclusion in Water Use Projections
Tab
le 4-8: Total Uses of Potable and Non-Potable Water - Projected (2030 – 2050) Tab
le 4-9: Total Projected Water Demands on Wholesaler (AF) Tab
le 5-1: SB x7-7 2020 Target Progress
Tab
le 6-1: Summary of Historical, Existing, and Planned Water Supplies (AFY) Tab
le 6-2: Source Water DesalInation
Tab
le 6-3: Wastewater Collected Within CMWD Water Service Area in 2025 Tab
le 6-4: Wastewater Treatment and Discharge within CMWD Water Service Area in 2025
Tab
le 6-5: Current and Projected Recycled Water Direct Beneficial Uses within Service Area 2025-2050
Tab
le 6-6: 2020 Recycled Water Use Projection Compared to 2025 Actual (AFY) Tab
le 6-7: Groundwater Basins in the Vicinity of CMWD
Tab
le 6-8: Expected Future Water Supply Projects or Programs Tab
le 6-9: Water Supplies – Actual
Tab
le 6-10: Water Supplies – Projected
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Table of Contents vi
Table 7-1: Constraints on Water Supplies
Tab
le 7-2: Basis of Water Year Data (Water Service Reliability Assessment) Tab
le 7-3: Supply and Demand Assumptions, as Percent of Normal Tab
le 7-4: Normal Water Year Supply and Use Comparison
Tab
le 7-5: Single Dry Year Supply and Demand Comparison
Tab
le 7-6: Multiple Dry Years Supply and Demand Comparison Tab
le 7-7: Five-Year Drought Risk Assessment Tables
Tab
le 8-1: Supply Source Availability Evaluation Methodology Tab
le 8-2: Water Shortage Contingency Plan Levels
Tab
le 8-3: Supply Augmentation and Other Actions
Tab
le 8-4: Demand Reduction Actions
Tab
le 8-5: CMWD Penalties for Use Restriction Violations
Tab
le 8-6: Impacts to Revenues and Methods to Address Impact Tab
le 8-7: Impacts to Expenditures and Methods to Address Impacts Tab
le 8-8: Methods for Measuring Water Use Reductions
Tab
le 9-1: Drought Response Levels
Tab
le 9-2: 2026 Residential Customer Billing Rates for Potable Water Tab
le 9-3: 2026 Commercial Customer Billing Rates for Potable Water Tab
le 9-4: Residential Water Conservation Rebate
Tab
le 9-5: Commercial Water Conservation Rebates
Tab
le 10-1: Notification to Cities and Counties

FIGURES
Figure ES-1: CMWD’s Historical, Current, and Projected Water Use Figure 3-1: Carlsbad Municipal Water District Service Area Figure 3-2: Comparison of 2025 Climate to Historic Average for Carlsbad, California Figure 3-3: Disadvantaged Communities
Figure 3-4: Major Water Infrastructure
Figure 4-1: Historical, Current, and Projected Water Use (AFY) Figure 6-1: CMWD Water Service Systems
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APPENDICES
Appendix A: Notification
Appendix B: UWMP Adoption Resolution (to be Included in Final) Appendix C: UWMP Checklist
Appendix D: UWMP Required Tables
Appendix E: City of Carlsbad Climate Change Vulnerability Assessment Appendix F: AWWA Water Audit FY2025
Appendix G: DWR Appendix O Energy Intensity Tables
Appendix H: CMWD Water Code Title 3 - Environment
Appendix I: 2023 City of Carlsbad Hazard Mitigation Plan Appendix J: Reporting on Reduced Delta Reliance

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ACRONYMS AND ABREVIATIONS
AB Assembly Bill
ACS American Community Survey
AF Acre-feet
AFY Acre-feet per year
AHLF Agua Hedionda Lagoon Foundation
AMI Advanced Metering Infrastructure
AWWA American Water Works Association
BMP Best management practices
CASGEM California Groundwater Elevation Monitoring
CFS Cubic feet per second
CII Commercial/Industrial/Institutional
CIP Capital Improvement Program
CMWD Carpinteria Municipal Water District
CWC California Water Code
DACs Disadvantaged Communities
DMM Demand management measure
DRA Drought Risk Assessment
DWR Department of Water Resources
EI Energy Intensity
ESP Emergency Storage Plan
EWA Encina Wastewater Authority
EWPCF Encina Water Pollution Control Facility
FTE Full-time employee
GHG Greenhouse gases
GPCD Gallons per capita per day
GPSCD Gallons per service connection per day
HOA Homeowners’ Association
LWWD Leucadia Wastewater District
MG Million gallons
Mg/L Milligrams per liter
Mgd Million gallons per day
MHI Median household income
MWD Metropolitan Water District
MWELO Model Water Efficient Landscape Ordinance
NEPA National Environmental Policy Act
NOAA National Oceanic and Atmospheric Administration
NSDWRC North San Diego Water Reuse Coalition
ntu Nephelometric Turbidity Unit
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OMWD Olivenhain Municipal Water District
QWEL Quality Water Efficient Landscaper
SCADA Supervisory Control and Data Acquisition
SDCWA San Diego County Water Authority
SDG&E San Diego Gas & Electric
SEJPA San Elijo Joint Powers Authority
SEWRF San Elijo Water Reclamation Facility
SFID Santa Fe Irrigation District
SWP State Water Project
SWRCB State Water Resources Control Board
TAP Tri-Agency Pipeline
TDS Total dissolved solids
UWMP Urban Water Management Plan
VWD Vallecitos Water District
WELO Water Efficient Landscape Ordinance
WRF Water Recycling Facility
WSCP Water Shortage Contingency Plan
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EXECUTIVE SUMMARY
Preparation of an Urban Water Management Plan (UWMP) is required by California Department of Water Resources (DWR) for all urban water suppliers within the State of California. Urban water suppliers are defined as organizations that provide water to more than 3,000 customers or that supply more than 3,000 acre -feet (AF) of water annually.

UWMPs must comply with the California Water Code (CWC) and the Urban Water Management Planning Act (Act).

The report is the 2025 Urban Water Management Plan (2025 UWMP) for Carlsbad Municipal Water District (CMWD), which will be adopted by CMWD’s Board of Directors and submitted to DWR by July 1, 2026. The 2025 UWMP meets the requirements of state law and includes an analysis of long-term water supply and demand planning for CMWD.

Table ES-1 includes a summary of each section of the 2025 UWMP.

TABLE ES-1: ORGANIZATIONAL OVERVIEW OF THE 2025 UWMP
Section Section Name Information Contained within Section Section 1 Introduction and
Overview
• General legal requirements for the 2025 UWMPs
• Relation of UWMP to local planning efforts
Section 2 Plan Preparation • Plan preparation
• Agency coordination and outreach
• Document overview
Section 3 System Description • History of CMWD
• General description of CMWD’s service area, including hydrologic and climate characteristics
• Current and projected population
• Description of CMWD’s water system
• Overview of potential impacts of climate change
Section 4 Water Use • Overview of past water use
• Description of water use by sector
• Summary of existing water use in 2025
• System water losses
• Water use projections through 2050
• Information about lower income households
Section 5 SB X7-7 Targets and
Reporting
• Reporting on 2020 target compliance
Section 6 Water Supply • Existing and projected supplies, including purchased and imported water, desalinated water, and recycled water
• Description of potential future water projects
• Climate change impacts on supplies
• Energy intensity of water operations
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Section Section Name Information Contained within Section Section 7 Water Supply
Reliability and
Drought Risk
Assessment
• Constraints on each of CMWD’s supplies
• Projections for water supply and water demands under
normal, single dry, and multiple dry year conditions
• Drought risk assessment
Section 8 Water Shortage
Contingency Plan
• Annual supply and demand reliability assessment procedures • Overview of CMWD’s water shortage stages
• Prohibitions enacted during water shortages
• Methods for reducing water use
• Catastrophic supply interruption plan
• Shortage communication protocol
• Financial impacts of water shortage
• Water shortage contingency plan monitoring, reporting, and refinement procedures
Section 9 Demand
Management
Measures
• Summary of CMWD’s demand management measures (DMM)
implemented over past five years
• Summary of future DMM implementation
Section 10 Plan, Adoption,
Submittal, and
Implementation
• Summary of UWMP review and notification process
• Overview of the UWMP adoption process
• Implementation of the 2025 Urban Water Management Plan CMWD Service Area and Water Supplies
CMWD’s service area is in northern San Diego County and comprises about 32 square miles. CMWD serves approximately 82% of the City of Carlsbad. Olivenhain Municipal Water District (OMWD) and Vallecitos Water District (VWD) serve the remaining southeastern portion. CMWD currently serves approximately 96,000 residents, and its population is projected to grow to over 119,000 by 2035, after which it is expected to remain stable. CMWD experiences a Mediterranean climate, characterized by mild temperatures throughout the year. CMWD averages 11 inches of precipitation each year and temperatures are, on average, 64 degrees in January and 75 degrees in August.

CMWD purchases potable water from the San Diego County Water Authority (SDCWA), which includes desalinated seawater. SDCWA sells water to CMWD and 21 other retail water agencies. SDCWA receives its water supplies from the Colorado River, Sacramento- San Joaquin Delta, and the Carlsbad desalination plant. It also purchases water from the Metropolitan Water District of Southern California.

CMWD also purchases, produces and sells recycled water. Recycled water is used for irrigation, and this reduces the amount of drinking water that is used. Recycled water is produced by CMWD at the Carlsbad Water Reclamation Facility (WRF). CMWD purchases additional recycled water from VWD’s Meadowlark WRF. CMWD completed its Phase III Recycled Water Project and expanded the capacity of the Carlsbad WRF to 7.0 mgd. As of May 12, 2026
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December 2025, this distribution system supplies more than 1,015 recycled water customers.

Moving forward, CMWD plans to increase local supply reliability by continuing to work with neighboring agencies on a North County One Water Project, which would convert ocean-discharged effluent into treated drinking water. Additionally, CMWD plans to add more recycled water customers where the system expansion supports . CMWD entered into an agreement in April 2016 to buy an exact amount (2,500 AFY) of desalinated seawater from the SDCWA. This water is considered local supply and can be counted on for CMWD customers at all times that the plant is producing water. CMWD may continue to explore groundwater as a local supply source; however, CMWD must re -establish its groundwater rights to do so.

TABLE ES-2: SUMMARY OF CURRENT AND PROJECTED SUPPLIES (AFY) Source 2025 2030 2035 2040 2045 2050
SDCWA Purchases 11,962 12,415 13,674 13,763 13,868 13,987 Seawater Desalination 2,500 2,500 2,500 2,500 2,500 2,500 Recycled Water 3,708 3,898 4,218 4,218 4,218 4,218
Total Water Supplies 18,170 18,813 20,392 20,481 20,586 20,705 Notes: Recycled water supplies include purchases from VWD and supplies from the Carlsbad WRF. It is assumed CMWD’s contract for 2,500 acre-feet per year of desalinated supply will be renewed when the current contract expires in 2046.

CMWD Current and Projected Water Demands
CMWD’s past water demands have varied from year to year, mainly because of the annual variations in weather and the economy, although CMWD’s service area is host to a substantial tourist and temporary population throughout the year as well. In addition, all urban water suppliers throughout California were mandated by the Water Conservation Act of 2009 (also known as SB X7-7) to reduce per capita potable water demands 20% by 2020. Although not required for the 2025 UWMP, CMWD estimated its 2025 gallons per capita per day (GPCD) water use to be 134, showing that CMWD remains in compliance with its target. Table ES-3 shows the baselines and targets for CMWD for compliance with SB X7-7.

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TABLE ES-3: SBX7-7 BASELINES AND TARGETS FOR CMWD
Baseline
Period
Start
Years
End
Years
Average
GPCD
2015
Target
2020
Target
2020
Actual
2025
Estimate
10-15 year 1999 2008 259 233 207 134 134
CMWD expects that ongoing conservation and increased recycled water use will reduce drinking water demands, further lowering overall gallons per person per day. For example, the Department of Water Resources (DWR) and the State Water Resources Control Board (SWRCB) recently implemented reporting requirements under Assembly Bill 1668/ Senate Bill 606, known as, “Making Conservation a California Way of Life.” As part of the reporting requirements, public water systems must begin implementing AB 1572, prohibit ing the use of potable water to irrigate nonfunctional turf in most government, commercial, industrial, institutional (CII), homeowners’ association (HOA) common areas, and community service organization properties, beginning in 2027 for governmental properties, 2028 for CII properties and 2029 for HOAs.
1 At the same time, CMWD recognizes that the population and housing inventory in Carlsbad is and will continue to increase in response to recent State regulations that require local jurisdictions to plan to increase their housing availability. For the purpos es of the 2025 UWMP, CMWD expects growth in its residential water use sectors over the next decade, eventually stabilizing in 2035 as the City of Carlsbad reaches build-out.

Table ES-4 summarizes CMWD’s baseline demands, conservation, recycled water use, and overall drinking water demand projections.

Figure ES-1 shows past and future water use, by use sector. Recycled water is also shown to provide an overall summary of CMWD’s water supply. Population is also included to illustrate how water demand has changed relative to population growth.

Future demands assume a normal rainfall year.

1 Residential customers may continue to use potable water for irrigation of their turf lawns.

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TABLE ES-4: SUMMARY OF PROJECTED DEMANDS
Water Use Type 2025 2030 2035 2040 2045 2050
Single Family 7,254 7,897 8,716 8,716 8,716 8,716
Multi-Family 1,862 2,128 2,464 2,464 2,464 2,464
Commercial 2,636 2,913 3,066 3,226 3,395 3,573
Industrial 38 38 40 42 44 46
Institutional/Governmental 122 145 152 160 169 177
Agricultural 145 163 163 163 163 163
Landscape (potable) 1,502 1,227 1,136 1,052 974 902
Distribution System Water
Loss (Real + Apparent
Loss)
863 363 393 396 398 401
Other (Unbilled metered +
unbilled unmetered) 40 41 44 44 45 45
Landscape (Recycled) 3,708 3,898 4,218 4,218 4,218 4,218

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FIGURE ES-1: CMWD’S HISTORICAL, CURRENT, AND PROJECTED WATER USE

CMWD Water Use Conservation
Title 3 Environment, of the Carlsbad Municipal Water District Water Code prohibits water waste and encourages conservation within CMWD’s service:
• Chapter 3.12 Drought Response follows the SDCWA’s Model Drought Ordinance and creates a six-level Water Shortage Contingency framework, consistent with DWR guidance. This framework gives CMWD the authority to declare shortage levels and implement progressi vely stronger conservation measures as supply conditions change, ensuring a clear and effective response to drought. • Chapter 3.08 Recycled Water requires the use of recycled water where feasible, consistent with public health, safety and welfare, legal, and environmental requirements.
• Chapter 3.04 Emergency Water Management Program establishes four water conservation stages, describes when they would be enacted, and applicable conservation measures and penalties.

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Additionally, CMWD conducts public education and outreach efforts to promote water conservation, using both direct customer engagement and regional programs offered through SDCWA. Outreach includes quarterly customer communications, participation in community events, distribution of conservation materials, and coordinated regional initiatives such as landscape contests and potable‑reuse education. Through the SDCWA, CMWD also supports free residential workshops, supports school assemblies and teacher resources, and runs an annual fourth‑grade art contest. These combined efforts support long‑term water‑use efficiency across the community.

CMWD Water Supply Reliability
One of the key requirements to include in a UWMP is a future supply reliability analysis that demonstrates the supply -demand balance in normal, single -dry, and multiple -dry year rainfall conditions. Consistent with SDCWA’s 2025 UWMP, CMWD projects that demands will increase as weather gets hotter and drier during the single -dry year and multiple-dry year scenarios. Recycled water supplies and CMWD’s local desalinated water supply would remain steady in all hydrologic scenarios because they are both drought- proof supplies. Changes in demand would change how much water CMWD purchases from SDCWA. SDCWA and CMWD have coordinated on this UWMP and project that water supply will be adequate to meet demand during a drought. In the unlikely event that SDCWA cannot fully meet CMWD’s water demands, CMWD would receive advance notice and implement the appropriate water‑saving measures outlined in its Water Shortage Contingency Plan, described in detail in Chapter 8. CMWD remains confident in its ability to reliably serve customers through both short‑ and long‑term drought conditions.

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1. INTRODUCTION AND OVERVIEW
The 2025 Urban Water Management Plan (2025 UWMP) addresses the Carlsbad Municipal Water District’s (CMWD) water supply sources, projected water demands, and supply reliability. The 2025 UWMP presents a comparison of projected water supplies to water demands during normal year, a single-dry year, and five consecutive dry years. It also includes CMWD’s Water Shortage Contingency Plan (WSCP), which is required for water suppliers to demonstrate they are able to respond effectively during periods of water shortage or drought. This chapter provides an introduction to the purpose of the 2025 UWMP and an overview of the Urban Water Management Planning Act.

1.1 Background and Purpose
Water planning is critical in California to prepare for longer droughts, expected long-term climate changes, and regulatory changes. Prior to the adoption of the Urban Water Management Planning Act (Act), water suppliers were not required to conduct long-term water resources planning, which could have left agencies vulnerable to supply disruptions during periods of drought or other supply shortages. The Act was adopted to require a minimum level of resource assessment and planning by water suppliers in order to reduce susceptibility to supply shortages. Water resources planning at the local level also allows for local community involvement , as well as consideration of unique circumstances and local conditions of the individual agency. The 2025 UWMP is an update to CMWD’s 2020 UMWP and WSCP.

1.2 California Urban Water Management Planning Act
The 2025 UWMP has been prepared in accordance with the Act, as amended, California Water Code (CWC) Division 6 Part 2.55 §10608 and Part 2.6, §10610 through 10657. The Act became part of the California Water Code with the passage of Assembly Bill 797 during the 1983–1984 regular session of the California legislature. It requires every urban water supplier that provides water for municipal purposes to more than 3,000 connections or supplying more than 3,000 acre-feet (AF) of water annually to adopt and submit a plan every five years to the California Department of Water Resources (DWR). The Act was amended in November 2009 with the adoption of Senate Bill (SB) x7-7. SBx7-7 set a goal of achieving a 20% reduction in urban per capita water use statewide by 2020. The 2025 UWMP demonstrates consistency with the baselines and achievement of the targets that were established for SBx7 -7 compliance in CMWD’s 2010 UWMP and achieved by the 2020 UWMP. There have been no major new requirements related to Urban Water Management Plans (UWMPs) for 2025. However, since the 2020 UWMP cycle, the Water May 12, 2026
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Code was updated to require water suppliers report on their 2028 Water Loss Standards in their UWMPs.

Additionally, although not a requirement for UWMP reporting, SB 606 and Assembly Bill (AB) 1668 established a statewide framework for long-term water conservation and drought resilience planning. Collectively referred to as “Making Conservation a California Way of Life,” the bills are companion measures that align state water -efficiency targets with local water -supply planning to achieve statewide water conservation goals, while maintaining reliable water supplies. Water Code Section 10609.2, added by AB 1668, directs the SWRCB, in coordination with the DWR, to adopt Urban Water Use Objective (UWUO) standards and performance measures for commercial, industrial, and institutional (CII) water use. The Water Code requires annual reporting on actual water usage and grants the SWRCB the authority to monitor, verify and take corrective action to remedy violations if a supplier is non-compliant. These laws expand authorities and requirements for urban water suppliers, while maintaining the foundational provisions of SB X7-7.

The Act states that urban water suppliers should make every effort to establish the appropriate level of reliability in water service to meet the needs of its various categories of customers during normal, dry, and multiple dry years. The required contents of the 2025 UWMP, as well as how urban water suppliers should adopt the UWMP, are also described in the Act. The 2025 UWMP also describes demand management measures that CMWD has implemented, or is planning to implement, which could help address urban water use objectives that the California Water Code required suppliers to develop for urban and agricultural sectors in 2023.

The 2025 UWMP has been developed in accordance with the DWR Urban Water Management Plan Guidebook 2025 (2025 Guidebook), which provides guidance to agencies on how to include the information required under the CWC, as amended. In accordance with the CWC, this Plan will be adopted and submitted to DWR by July 1, 2026.

1.3 Relation to Other Planning Efforts
UWMPs allow for integration of information from other planning documents, as well as regional planning efforts. The 2025 UWMP synthesizes information from CMWD’s current planning documents and complements regional planning documents. Upon completion, the 2 025 UWMP will help to inform other planning decisions, such as updates to the Carlsbad General Plan, and can be used to establish priorities in other planning efforts.

The information developed for the 2025 UWMP is also developed in parallel and used to inform and support the San Diego County Water Authority’s (SDCWA) 2025 Urban Water Management Plan, which provides water reliability assessment for the region’s water May 12, 2026
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wholesaler. In addition, Appendix K demonstrates consistency with the Delta Plan’s policy to reduce reliance on Sacramento-San Joaquin Delta (Delta) through the development of local supplies.

Relevant, related planning efforts include the following:

1. CMWD, 2019 Potable Water Master Plan – Documents existing water system facilities and demands, identifies existing deficiencies in the system, confirms facility sizing, and recommends a future capital improvement program (CIP) based on updated water demand projections.

2. CMWD, 2019 Recycled Water Master Plan – Evaluates the capabilities of the existing recycled water system, defines the most cost-effective system expansions through build-out conditions, and develops a recycled water CIP.

3. CMWD, 2019 Utilities Asset Management Master Plan – Supports 2019 Potable Water Master Plan with condition assessment and CIP planning with respect to asset inventory and valuation.

4. CMWD, 2025 Potable and Recycled Water Cost-of -Service Study – Study of CMWD’s potable water, recycled water, and wastewater systems and to develop a rate plan for the 2025-2029 period.

5. CMWD, 2025 Wastewater Cost of Service Study – Study of CMWD’s potable water, recycled water, and wastewater systems and to develop a rate plan for the 2025- 2029 period.

6. SDCWA, 2025 Urban Water Management Plan – Identifies regional water sources and volumes for SDCWA’s service area, including supply reliability analysis of the wholesale (imported + desalinated seawater) supply.

7. City of Carlsbad, 2023 Climate Change Vulnerability Assessment – Evaluates how climate change may affect vulnerable communities, natural resources, facilities, buildings, services, and infrastructure.

8. City of Carlsbad, 2024 Climate Action Plan – Outlines updated strategies to reduce greenhouse gas emissions and promote environmental sustainability.

9. City of Carlsbad, 2015 General Plan - Carlsbad’s 2015 General Plan serves as a blueprint for future growth and development within the city. It includes a safety element that addresses seismic conditions and risk.

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10. City of Carlsbad 2021- 29 Housing Element, April 2021 – This update to the City’s General Plan addresses substantive changes to State housing law since the city’s last 2017 Housing Element including the Affordable Housing Streamlined Approval Process: Senat e Bill 35 (2017), Assembly Bill 168 (2020) and Assembly Bill 831 (2020).

11. City of Carlsbad 2024 General Plan Update for Land Use and Community Design - These updates address land use designations, population density and building intensity standards.

12. City of Carlsbad 2023-24 Growth Management Program Annual Monitoring Report, April 2025.

13. County of San Diego, 2023 Multi -jurisdictional Hazard Mitigation Plan – The revised Multi-jurisdictional Hazard Mitigation Plan was adopted by the County of San Diego in 2023 and it is a countywide plan that identifies risks and ways to minimize damage by natural and manmade disasters.

14. CMWD Annual Population Projections, 2025 -2050, Technical Memorandum.

Prepared by Woodard & Curran, April 2, 2025 – Estimates long-range population and demographic projections for use in water demand forecasts.

15. CMWD Seasonal Population Variance Analysis Technical Memorandum. Prepared by Woodard & Curran, September 8, 2025 - Quantifies a volume for the Significant Fluctuations in Seasonal Populations variance for the “Making Conservation a California Way of Life” annual reporting.

1.4 Lay Description
The Executive Summary of the 2025 UWMP provides a lay description of the fundamental determinations of the UWMP, particularly regarding water service reliability, potential issues, and strategies for managing reliability risks.

1.5 Organization of the Urban Water Management Plan
The 2025 UWMP is organized into the following 10 sections:
• Section 1: Introduction and Overview – Provides an overview of the UWMP Planning Act and this UWMP’s purpose. It also outlines how this UWMP relates to other local and regional planning efforts.
• Section 2: Plan Preparation – Describes the basis for preparing the 2025 UWMP.

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• Section 3: Description of Service Area – Details CMWD’s service area, climate, population, land use, water system infrastructure, and socioeconomic characteristics.
• Section 4: Water Use – Provides an overview of historical, current, and projected water use across various sectors.
• Section 5: SB X7-7 Targets and Reporting – Describes meeting the state-mandated requirements for per capita water use.
• Section 6: Water Supply – Describes CMWD’s current and planned water sources. • Section 7: Water Supply Reliability and Drought Risk Assessment - Evaluates the reliability of water supplies under normal, single-dry, and multiple-dry scenarios. • Section 8: Water Shortage Contingency Plan – Outlines triggers, mandatory reduction levels, and response actions to address water shortages at varying levels. • Section 9: Demand Management Measures – Describes CMWD’s conservation programs.
• Section 10: Plan Adoption, Submittal, and Implementation – Summarizes CMWD’s public hearing and adoption process.

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2. PLAN PREPARATION
Section 2 Plan Preparation addresses CMWD’s basis for preparing a UWMP and related information. It also provides a description of how the 2025 UWMP is organized and identifies general details regarding CMWD and the data used for this plan.

2.1 Plan Preparation and Implementation
CMWD is a retail water agency that supplied 18,170 AF of water (potable and recycled) to a service area with a population of 96,371 people and 30,521 connections in 2025. Of this total, 13,559 AF was delivered as potable water to 29,506 connections, and 3, 708 AF was delivered as recycled water to 1,015 connections. Approximately 903 AF was lost as non- revenue water.
1 Non-revenue water includes real losses, defined as physical water losses such as leaks, apparent losses, which include “paper losses” or water lost through inaccurate measuring or recording, and unbilled water, which includes water used in activities such as firefighting, flushing of water mains, or water used for distribution operations. The 2025 UWMP was prepared as an individual plan in coordination with appropriate agencies. This chapter provides descriptions of agency coordination, public participation, Plan adoption, and Plan organization. Table 2-1, Table 2-2, and Table 2-3 provide information on CMWD as a retail water agency and its water system, and how data will be reported throughout the 2025 UWMP.

TABLE 2-1: PUBLIC WATER SYSTEM
DWR Table 2-1 Retail: Public Water Systems
Public Water System
Number Public Water System Name
Number of
Municipal
Connections 2025
Volume of
Water Supplied
2025 (AFY)
CA3710005 Carlsbad Municipal Water District 29,506 14,462 Notes: This table only reflects potable water connections and deliveries. CMWD’s recycled water system has 1,015 connections and supplied 3,708 AF in 2025.

1 In this UWMP, data are reported for the calendar year 2025, except for data on water losses, which CMWD began reporting on a fiscal year basis in 2024-25.

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TABLE 2-2: PLAN IDENTIFICATION
DWR Table 2-2: Plan Identification
Select
Only One Type of Plan
Name of RUWMP
or Regional
Alliance
if applicable
Individual UWMP

Water Supplier is also a member of a RUWMP

Water Supplier is also a member of a Regional Alliance

Regional Urban Water Management Plan (RUWMP)
Notes: CMWD is a member agency of the San Diego County Water Authority.

TABLE 2-3: SUPPLIER IDENTIFICATION
DWR Table 2-3: Supplier Identification
Type of Supplier (select one or both)
Supplier is a wholesaler

Supplier is a retailer
Fiscal or Calendar Year (select one)

UWMP Tables are in calendar years

UWMP Tables are in fiscal years
Units of measure used in UWMP*
Unit AF
* Units of measure (AF, CCF, MG) must remain consistent throughout the UWMP as reported in Table 2-3.

2.2 Coordination and Outreach
The Act requires CMWD to coordinate the preparation of its plan with other appropriate agencies in the area, including other water suppliers that share a common source, water management agencies, and relevant public agencies, to the extent practicable. Whi le preparing the 2025 UWMP, CMWD attended workshops conducted by DWR to discuss the requirements of the Act and attended meetings with SDCWA, CMWD’s wholesale May 12, 2026
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water supplier. SDCWA’s 2025 Urban Water Management Plan should be consulted for details regarding CMWD’s wholesale water supplies. Table 2-4 identifies SDCWA as CMWD’s wholesale water supplier, with whom CMWD has coordinated on its supply and demand evaluations.

TABLE 2-4: WATER SUPPLIER INFORMATION EXCHANGE
DWR Table 2-4 Retail: Water Supplier Information Exchange The retail supplier has informed the following wholesale supplier(s) of projected water use in accordance with CWC 10631.

Wholesale Water Supplier Name
San Diego County Water Authority
CMWD worked closely with the City of Carlsbad’s Community Development Department in the preparation, updates on land use and development in CMWD service area of the City, and review of 2025 UWMP elements. CMWD worked with the San Diego Association of Governments (SANDAG) for information on land use. In preparing the recycled water elements of the 2025 UWMP, CMWD consulted with the agencies responsible for the existing and potential sources of recycled water in northern San Diego County, including Vallecitos Water District (VWD), Leucadia Wastewater District (LWWD), Encina Wastewater Authority (EWA), City of Escondido, City of Oceanside, Olivenhain Municipal Water District (OMWD), Rincon del Diablo Municipal Water District (Rincon), San Elijo Joint Powers Authority (SEJPA), and Santa Fe Irrigation District (SFID). Table 2-5 provides a summary of CMWD’s coordination with the appropriate agencies.

TABLE 2-5: COORDINATION WITH AGENCIES
Organization/Agency Name
Level of Participation
Sent 60-Day Notice of
2025 UWMP update and
Public Hearing
Contacted for Assistance
City of Carlsbad X X
City of Encinitas X
City of Escondido X X
City of Oceanside X X
City of San Diego X
City of San Marcos X
City of Vista X
County of San Diego X
Encina Wastewater Authority X X
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Organization/Agency Name
Level of Participation
Sent 60-Day Notice of
2025 UWMP update and
Public Hearing
Contacted for Assistance
Leucadia Wastewater District X X
Metropolitan Water District of Southern
California X
Olivenhain Municipal Water District X X
Rincon del Diablo Municipal Water District X X
San Diego Association of Governments X X
San Diego County Water Authority X X
San Diego Local Area Formation
Commission X
San Elijo Joint Powers Authority X X
Santa Fe Irrigation District X X
Vallecitos Water District X X
San Dieguito Water District X
Vista Irrigation District X

2.3 Public Participation
CMWD encourages community and public involvement in the 2025 UWMP. CMWD scheduled a public hearing for May 12, 2026, to provide an opportunity for CMWD’s customers to learn about the water supply situation and plans to continue to provide a reliable water supply for the future. The hearing is an opportunity for people to ask questions regarding the 2025 UWMP and Water Shortage Contingency Plan. A 60-day notice of the public hearing was provided to San Diego County and adjacent cities and other entities on March 9, 2026. The notification list is included in Appendix A.

Public hearing notifications were published in the San Diego Union Tribune on April 28 and May 5, 2026. A copy of the draft 2025 UWMP was available for a 30-day public review beginning March 11, 2026, on the City of Carlsbad’s website at www.carlsbadca.gov and a hard copy is available for review at City offices. Copies of the n otices are included in Appendix A . The 2025 UWMP is scheduled to be adopted by the Board of Directors following the public hearing on May 1 2, 2026. A copy of the adoption resolution w ill be provided in Appendix B.

The 2025 UWMP will be submitted to DWR, the California State Library, and San Diego County within 30 days after adoption. The final 2025 UWMP will be available for public May 12, 2026
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review on the City of Carlsbad’s website (www.carlsbadca.gov) within 30 days after filing a copy of the 2025 UWMP with DWR. CMWD will implement the adopted 2025 UWMP in accordance with the schedule described in this UWMP.

2.4 Plan Organization
The 2025 UWMP generally follows the suggested organization in the 2025 Guidebook.

Section 1 provides an overview of the background and purpose of the Urban Water Management Planning Act and the 2025 UWMP. Section 2 describes the plan preparation process an d plan organization. Section 3 provides a description of the service area, climate, and water system. Section 4 presents historical and projected water use and demands. Section 5 presents SB X7-7 2020 Targets and 2020 Reporting, as required.

Section 6 describes CMWD’s water supplies. Section 7 provides an assessment of local and regional water supply reliability. Section 8 discusses water shortage contingency planning. Section 9 presents demand management measures. Section 10 discusses the plan adoption, submittal and implementation process.

Relevant supporting documents have been included as appendices where indicated. DWR has provided a checklist of the items that must be addressed in each UWMP as required by the Act. This identifies exactly where in the UWMP each item has been addressed and is provided in Appendix C . A copy of all the required DWR tables are provided as Appendix D . CMWD has elected to include additional tables in various chapters to provide clarity and support chapter narratives. Throughout the 2025 UWMP, tables are numbered sequentially, with tables containing information addressed in the required DWR tables indicated in the dark blue header row of the given table:

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3. SYSTEM DESCRIPTION
This section describes CMWD’s service area and water system, including climate, current and projected population, and other social, economic, and demographic factors affecting CMWD’s water management planning.

3.1 Description of Service Area
CMWD’s service area is 20,682 acres or approximately 32 square miles. CMWD provides potable and recycled water supply to the majority (approximately 82%) of the City of Carlsbad (City or Carlsbad). CMWD’s boundary, which defines the Study Area for UWMP is shown in Figure 3-1. VWD and OMWD supply water to the remaining parts of the City of Carlsbad.

CMWD supplies potable water within its service area, and recycled water within a portion of its service area. In 2025, CMWD purchased 100% of its potable water supply from the San Diego County Water Authority (SDCWA). Of this amount, 18% is desalinated seawater produced at the Carlsbad Desalination Plant and delivered via SDCWA infrastructure. This desalinated seawater is considered a guaranteed local supply. The potable water distribution system consists of 457 miles of pipeline, 74 pressure regulating stations, three pump stations, and nine reservoirs. CMWD supplies recycled water from two supply sources, which include 97 miles of pipeline, six pressure zones, four storage tanks, four pumping stations, and four pressure regulating stations. Sanitary sewer collection service within the CMWD service area is provided by City of Carlsbad (City) , VWD and LWWD.

Wastewater treatment is provided by Encina Wastewater Authority (EWA) through the Encina Water Pollution Control Facility (EWPCF), located in Carlsbad. Tertiary treatment and recycled water production are provided by CMWD’s Carlsbad Water Recycling (WRF) and VWD’s Meadowlark Water Reclamation Facility. A detailed description of major water, wastewater, and recycled water infrastructure facilities is provided in Section 3.3 Description of Water System, below.

Carlsbad’s housing stock consists primarily of single-family homes, with some multi-family and mobile homes. Single -family residences generally contain larger landscaped areas, planted in turf and shrubbery, requiring more water for outdoor uses in comparison to other types of housing. The general characteristics of multi-family and mobile homes limit their outdoor landscaping and water use, although some condominium and apartment developments have both functional and ornamental landscaped areas. Many residential landscapes are irrigated by recycled water. Commercial users in CMWD’s service area include offices and commercial centers, which have limited outdoor water use, but also May 12, 2026
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include resorts, golf courses, and other tourism and recreational facilities; many of which use recycled water for landscaping, as well.

3.1.1 Agency Organizational Structure
CMWD is a subsidiary district of the City of Carlsbad. The City was incorporated in 1952, and the assets of the two previous water suppliers for the Carlsbad area were purchased by the City in 1957. CMWD was initially formed in 1954 to facilitate the trans fer of imported water to the unincorporated areas surrounding the City and to provide wholesale water to the newly formed City. In 1983, the City conveyed all its functional water responsibilities for the provision of water service to CMWD. In 1990, CMWD became a subsidiary district of the City of Carlsbad. The five -member Carlsbad City Council governs CMWD and acts as CMWD’s Board of Directors. CMWD’s service area covers approximately 82% of the incorporated City. Additional history of water services withi n CMWD’s service area is provided in Section 3.4 Water System Background, below.

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FIGURE 3-1: CARLSBAD MUNICIPAL WATER DISTRICT SERVICE AREA

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3.1.2 Service Area Climate
Carlsbad’s climate is characteristically Mediterranean with mild temperatures year-round.

This mild climate is derived equally from the warm ocean water being pulled north from Mexico and from its subtropical, semi-desert locale. The result is temperatures with an average high of 64 degrees in January and 75 degrees in August, with an average annual rainfall of about 11 inches. Data from the National Oceanic Atmospheric Administration’s (NOAA) climate station at the McClellan Palomar Airport show that 2025 mean monthly temperatures were close to the historic average, while monthly total precipitation was above the historic average for the early part of the year, but below the historic average in the end of the year (historic baseline average is calculated for the 30-year period from 1981 to 2010). In 2025, the winter months received more rainfall compared to normal historic precipitation. The months of September through February can bring warm wind from the desert called a “Santa Ana.” Occurring about 10 days out of the year, these winds typically bring hot and dry conditions, which can spread and worsen wildfires (City of Carlsbad 2023). Figure 3-2 provides a comparison of 2025 precipitation and mean monthly temperatures with historic average climate, as recorded at the McClellan Palomar Airport located in Carlsbad. A detailed discussion of potential climate change impacts on CMWD’s service area is provided in Section 3.5 Climate Change, below.

FIGURE 3-2: COMPARISON OF 2025 CLIMATE TO HISTORIC AVERAGE FOR

CARLSBAD, CALIFORNIA
0 10
20 30
40 50
60 70
80 0

0.5 1

1.5 2

2.5 3

3.5 Temperature (F)
Precipitation (inches)
Normal Precipitation 2025 Precipitation Normal Temperature 2025 Temperature May 12, 2026
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3.1.3 Land Uses Within the Service Area
The City updated the Land Use and Community Design section of its General Plan in 2024.

The Land Use and Community Design section identifies current land uses, including residential, commercial and industrial, public and quasi-public uses, parks and recreation, agriculture, open space or natural areas, and vacant land. The remaining land is right-of- way. Table 3-1 provides a summary of the land use classifications and the total acres within the City of Carlsbad, according to the latest GIS data associated with the General Plan Update (City of Carlsbad 2024).

TABLE 3-1: LAND USE CLASSIFICATION WITHIN THE CITY OF CARLSBAD Land Use
Classification City Acres Percent of City of
Carlsbad Percent of CMWD
Residential 8,535 39% 30%
Commercial and
Industrial 2,654 12% 12%
Public and Quasi-Public 956 4% 3%
Open Space 9,182 42% 35%
Transportation Corridor 427 2% 2%
Village Barrio 264 1% 1%
Source: City of Carlsbad 2024 GIS Land Use Data
Existing land uses within the CMWD service area are primarily residential and parks and open space, with a mix of commercial and industrial. Additionally, a county airport, tourist attractions such as Legoland, and a mix of resorts and golf courses are located within CMWD’s service area. Residential land uses make up approximately 35% and parks and open space land uses make up approximately 40% of the total service area.

The City has maintained a Growth Management Plan and a Growth Database since 1986 to monitor development within the city and to ensure that adequate facilities are constructed in an orderly manner to support future growth. Proposition E established limits, or caps, on the number of homes in the city. However, recent State housing laws (Senate Bills 166 and 330), preempt the City’s ability to require compliance with the housing caps and limit the City’s ability to restrict development. The City’s recently adopted annual Growth Management Program Monitoring Report (City of Carlsbad 2025), addresses this increased growth, as discussed in further detail in Section 3.1.4.

SANDAG has completed a Series 15 forecast of land use for the City of Carlsbad (SANDAG 2026). Between 2022 and 2050 the total land area in the City of Carlsbad remains constant at 25,052 acres. Developed land increases from 18,605 acres in 2022 to 19,144 acres in 2050. Single-family land uses are projected to increase by 9% between 2022 to 2050, while multiple family land uses expected to increase by 13.5%. Other land uses are projected to May 12, 2026
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decrease. For example, agriculture and extractive land use is projected to decrease by 50% between 2022 to 2050.

3.1.4 Population and Demographics
To project CMWD’s future water demands and water use characteristics, future population and growth trends are essential. The population projections presented in Table 3-2 were developed using local planning data provided by the City of Carlsbad Planning Division.

The City anticipates buildout by 2035, and after 2035, it is estimated that the number housing units will remain relatively constant through the 2050 planning horizon. The City Planning Division provided the Yield Analysis for Density Bonus and Housing Element sites that contained housing site development projects and other approval and permit application dates. The Yield Analysis is a part of the City’s Growth Management Plan update and Housing Element update. The Yield Analysis included location, application date, proposed units, high-density allowed units, and application status for density bonus sites. For sites identified in the General Plan Housing Element as having development potential, the Yield Analysis included location, application status if applicable, proposed units, and high-density allowed units. A static 5.5% vacancy rate for housing units and an average of 2.63 persons per unit were used to estimate housing units and population from 2025 to 2035. The Yield Analysis included only sites within the CMWD service area.

TABLE 3-2: CMWD’S SERVICE AREA POPULATION – CURRENT AND PROJECTED DWR Table 3-1 Retail: Population – Current and Projected Population
Served
2025 2030 2035 2040 2045 2050
96,371 106,031 119,616 119,616 119,616 119,616
A secondary analysis was conducted to compare to the local projections. For the CMWD service area, the estimated annual growth rate based on the average annual population growth between 2021 and 2023 from the American Community Survey (ACS) program conducted by the US Census Bureau is 0.45%, while the average annual housing unit growth rate between 2021 and 2023 is 0.26%. Based on these growth rates, the population in the CMWD service area would be 95,682 in 2035 and 102,363 in 2050, which is lower than the local projections. The SANDAG Interim Series 15 Regional Growth Forecast projects a gradual increase in population within the CMWD service area, peaking at 105,640 in 2035. This trend is consistent with local projections, although SANDAG expects a lower p eak population in 2035. However, after 2035, SANDAG forecasts that the population begins to decline, reaching 103,033 by 2050. This is a result of SANDAG assumptions of a lower birth rate in 2050 due to an aging population and continuing trends of lower bi rth rates among younger individuals. Additionally, within an aging May 12, 2026
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population, SANDAG anticipates that there will be more deaths in 2050 compared to earlier years.

CMWD used local planning data and information on planned developments because the City of Carlsbad’s Planning Division anticipates full buildout by 2035 and housing units assumed to remain constant thereafter (Woodard & Curran 2025). With no additional residential growth projected beyond buildout, population within the service area is anticipated to remain stable. Table 3-3 provides a comparison of population growth, comparing the local planning data with estimates from SANDAG and the U.S. Census ACS.

TABLE 3-3: CMWD GROWTH POPULATION COMPARISON
Population Data 2025 2030 2035 2040 2045 2050
SANDAG Series 15 101,040 104,719 105,640 105,124 104,083 103,033 U.S. Census ACS 91,472 93,533 95,682 97,859 100,085 102,363 Local Planning Data1 96,371 106,031 119,616 119,616 119,616 119,616 1 Local planning data were used for population projections Water use in CMWD’s service area is closely linked to the local economy, population, and weather. Over the last century, a prosperous local economy has stimulated population growth, which in turn produced a relatively steady increase in water demand. However, fluctuating economic and weather conditions in the 1990s and lingering effects from the 1987-1992 drought resulted in deviations from historic demand patterns. By 1999, a new combination of natural population increases, and job creation surfaced as the primary drivers of water consumption increases. The recession that started in 2008 brought an increase in unemployment and decrease in housing prices that dampened population growth and water use. In addition, CMWD adopted a residential tiered water rate in July 2009 which may have further dampened demand by the residential population. In 2020, demand trends were lower than the long-term average prior to 2015, which was a result of drought response measures and State-mandated water use cutbacks in 2015 and 2016.

The COVID-19 pandemic that started in 2020 has resulted in increased unemployment and work -from-home patterns that resulted in additional long-term socioeconomic changes for the region. In the 2020 UWMP, CMWD expected water use in 2025 to be 20,520 AFY, which was a higher estimate than actual demand in 2025, which was 18,170 AFY. Current demand projections are anticipated to follow the same trends as the population projects. Demand is expected to increase through 2035 and then stay relatively constant as the City maintains buildout levels between 2035 through 2050.

CMWD’s service area is host to a substantial tourist and temporary population throughout the year, with overnight guests in the City of Carlsbad ranging between approximately 75,000 and 199,000 people per month. In 2025, CMWD evaluated its seasonal population May 12, 2026
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variance for the “Make Conservation a California Way of Life” regulation, as a result of 2018’s Assembly Bill 1668/Senate Bill 606 regulation. The analysis classified 2,215 premises as seasonally occupied based on water usage patterns (Woodard & Curran 2025). Water use is further described in Section 4 Water Use of the 2025 UWMP.

The population and housing inventory in Carlsbad is and will continue to increase from 2020 to 2035, eventually stabilizing in 2035. This trend is driven by recent State regulations (e.g., Senate Bills 166 and 330) that require local jurisdictions to plan to increase their housing availability in an attempt to increase available , affordable housing to moderate the high cost of living in California. For example, recent updates to the Housing Accountability Act, a state law that limits local governments’ deci sion-making authority over certain housing development projects, allow housing development projects to move forward as long they meet objective standards of the city land use regulations (e.g., housing element, zoning, subdivision standards, design criteria). CA Senate Bill 330, which became effective January 1, 2020, also limited cities’ ability to deny a housing project that meets established development requirements. Additionally, State density bonus law allows a developer to increase density (total numb er of homes) allowed on a property above the maximum set under a city’s local land use plan (Carlsbad General Plan) by as much as 100%. In addition, qualifying applicants can also receive reductions in required development standards such as setbacks and height limits when those standards prevent the applicant from achieving the density allowed under state law. Other tools include reduced or no parking requirements for certain project types. The City has taken steps to respond to the State regulations, including rezoning parcels as part of the General Plan Housing Element Program. The rezoning process included increasing the number of housing units allowed on properties that already allow housing, and converting government-owned, commercial, and vacant industrial properties to allow for housing. In addition, the City has updated its Growth Management Plan (City of Carlsbad 2025) to ensure the objective city land use regulations that developers will comply with are thorough and thoughtful. For example, the updated Growth Management Plan considers the implications of the rezoning program, such as adequate public facilities and public performance standards. New developments are in various stages of planning, design, and construction. During fiscal year 2023-2024, building permits were issued for 500 new dwelling units, including 73 accessory dwelling units, and for 181,758 square feet of new non-residential space (City of Carlsbad 2025). Rapidly increasing development cannot be restricted under any local laws, policies, or programs that aim to limit the amount of residential development (City of Carlsbad 2025).

The City of Carlsbad’s demographics vary in terms of income, age, education levels, and racial and ethnic composition. The City of Carlsbad has a median household income (MHI) of $139,326 (in 2023 dollars) and a poverty rate of 6.9%. About 23% of the popul ation is May 12, 2026
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under 18 years of age and 18.4% is over 65 years of age. Of the City’s population that is 25 years of age or older, 96.1% have a high school degree or higher, with 61.4% obtaining a bachelor’s degree or higher. About 66% of the population identify as Non-Hispanic white, 16.8% identify as Hispanic or Latino, 9.8% identify as Asian, and 4.6% identify as other or a mix of two or more races (US Census 2020). Of CMWD service area within the City of Carlsbad, about 8.35% is defined as disadvantaged communities (DACs), areas with an average MHI less than 80% of the statewide MHI of $77,067. Of these DAC areas, about

0.51% are considered severely disadvantaged communities (SDACs), defined as having an average MHI less than 60% of the statewide MHI (Figure 3-3).

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FIGURE 3-3: DISADVANTAGED COMMUNITIES

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3.2 Overview of Significant Water Uses
The primary water uses in CMWD’s service area are residential, commercial, industrial, agricultural, and irrigation. Residential water use represents the largest water use sector for CMWD. Residential water uses include both indoor and outdoor uses for single-family and multi-family categories. Commercial water uses generally consist of uses necessary for business operation and are more varied than residential uses. Major commercial water uses include restaurants, car washes, laundries, and hotels , as well as schools and churches. Commercial water uses also encompass resorts, golf courses, Legoland, and other tourism and recreational facilities. Industrial water uses include product processing, equipment cooling, sanitation and air conditioning. Agricultural water uses are relatively minor, and primarily consist of commercial strawberry and flower fields, and wholesale nursey operations. Irrigation water use fluctuates by season and primarily includes the irrigation of medians, slopes, and parkways. As shown in Table 4-2, key water users within CMWD’s service area in 2025 were residential, which represented 50% of total demands in 2025, and commercial, which accounted for 15% of total demands in 2025.

3.3 Description of Water System
CMWD currently receives 100% of its potable water supply through four SDCWA treated water turnouts. Two of the turnouts, Connections No. 6 and No. 2, are direct connections to SDCWA’s Second Aqueduct. Connection No. 6 supplies only CMWD, and Connection No. 2 is delivered through a VWD transmission main. Connections No. 3 and No. 4 are on SDCWA’s Tri-Agency Pipeline (TAP), which is supplied from the Second Aqueduct. Major water infrastructure facilities are shown in Figure 3-4.

Potable water is delivered within the CMWD service area through 457 miles of pipeline, 17 pressure zones, 74 pressure regulating stations, three pump stations, and nine reservoirs.

The CMWD water distribution system is flexible in that supply can be routed to different parts of the distribution system, as needed. The total operational storage for CMWD is 242.5 million gallons (MG).

CMWD also has an extensive recycled water distribution system. CMWD supplies recycled water from two sources through its recycled water distribution systems, which include 97 miles of pipeline, six pressure zones, four storage tanks, four pumping stations, and four pressure regulating stations. CMWD supplies a majority of recycled water from the Carlsbad Water Recycling Facility (WRF), owned by CMWD and operated by EWA. A portion of the eastern service area is served by a second supply source from VWD’s Meadowlark WRF. CMWD finished expanding its recycled water system with the Phase III Recycled Water Project. The Phase III Recycled Water Project, which began construction in 2015, included expansion of the existing Carlsbad WRF and construction of distribution May 12, 2026
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pipelines, storage, and related appurtenances. The Carlsbad WRF was expanded from 4.0 million gallons per day (mgd) to 7.0 mgd by installing additional filtration units and a chlorine contact basin. The Carlsbad WRF expansion was completed in 2018.

Approximately 85,000 linear feet of pipeline and a 1.5-million -gallon recycled water storage tank were constructed, existing potable water facilities were converted to recycled water use, and landscape irrigation water systems were retrofitted to use recycled water in eight expansion segment locations. Eighty -six (86) customers were connected to CMWD’s recycled water system, adding a recycled water demand of 338 AFY as a result of the Phase III Recycled Water Project. Where possible and existing infrastructure supports, CMWD plans to connect more recycled water customers as additional opportunities arise (CMWD 2024; CMWD 2025).

3.4 Water System Background
Water demands for the area were initially supplied by the privately held Carlsbad Mutual Water Company and Terramar Water Company through the utilization of local groundwater and surface water supplies. The Carlsbad Mutual Water Company’s groundwater wells began development prior to 1914 with rights to 2,382 AFY. In addition, a license was obtained (terminable by the State Division of Water Rights, DWR) for another 1,000 AFY. The Carlsbad Mutual Water Company constructed nine wells in the Mission Basin of t he San Luis Rey River, located in the City of Oceanside, generally near the intersection of Mission Avenue and Foussat Road. Prior to 1942, local groundwater was the only developed source of water for Carlsbad Mutual Water Company. Additionally, they constructed booster pumping stations, storage tanks, and transmission facilities to supply residential, commercial and agricultural users. In September 1941, Carlsbad Mutual Water Company completed construction of an earthen dam (Calavera Dam), which captured local surface water runoff creating Lake Calavera. Lake Calavera also included a 2-million-gallon per day (mgd) water filtration plant. A permit to divert 150 AFY from Calavera Creek was also obtained.

The Terramar Water Company constructed four wells located in Agua Hedionda Creek (referred to as the Cannon Well Field), a second connection to the Carlsbad Mutual Water Company’s pipeline from Lake Calavera at El Camino Real, a reservoir, plus a distribution system to supply residential, commercial, and agricultural users. The Cannon Well Field’s four wells were constructed beginning in 1950 and located at and around the Rancho Carlsbad Golf Course property. The groundwater pumped from these wells was the original supply for the Terramar Water Company and had a safe yield capacity estimated at 400 AFY. This groundwater was obtained from the Carlsbad hydrologic unit of the San Diego Region, a designation assigned by DWR. The four wells remain but are no long er operational and thus, CMWD does not currently pump groundwater from these wells.

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The City of Carlsbad was incorporated in 1952, and the assets of the Carlsbad Mutual Water Company and Terramar Water Company were purchased by the City of Carlsbad in an agreement dated August 30, 1957. The City operated and maintained both water systems from 1958 to 1962.

CMWD was formed in 1954 as a vehicle to bring imported water to the unincorporated areas surrounding the City of Carlsbad and to wholesale water to the newly formed City of Carlsbad. CMWD’s first meeting was held on March 22, 1954, and CMWD became a member of SDCWA that same year. CMWD began receiving imported water deliveries in 1955 through existing aqueduct connections located in the City of Escondido. CMWD constructed a pipeline in 1956 to convey imported water directly to the City of Carlsbad and uninc orporated areas within CMWD’s service area. In 1962, CMWD constructed Maerkle Dam (previously called Squires Dam) with a capacity of 600 AF in the Agua Hedionda Basin. CMWD also obtained a permit for surface water rights tributary to Maerkle Dam in the amount of 25 AFY.

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FIGURE 3-4: MAJOR WATER INFRASTRUCTURE

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As demands for water increased, seawater intrusion into the groundwater supply resulted in the gradual degradation of groundwater quality in the Mission Basin of San Luis Rey River. The total dissolved solids (TDS) content of the groundwater in the Mission Basin increased to the point where treatment would be required. At the same time, lower -cost imported water became available through CMWD. As a result of the availability of this alternative supply of water, the City of Carlsbad ceased extracting groundwater and suspended use of local surface water supplies by the end of 1962. As a result, the water filtration plant at Lake Calavera was dismantled because of regulations requiring that surface waters be fully treated prior to introduction into a potable water system. The cost to construct facilities to treat the small amount of infrequently occurring surface water was determined to be much greater than the comparable cost of imported water. The Mission Basin wells were beyond repair and subsequently removed by 2005, in accordance with California Department of Public Health requirements.

In an agreement dated May 25, 1983, the City of Carlsbad conveyed all its functional water responsibilities for the provision of water service to CMWD, including all the water facilities and groundwater and surface water rights purchased from Carlsbad Mutu al Water Company and Terramar Water Company in 1957. This included all existing water facilities and responsibility for planning, financing, and construction of all major capital facilities necessary to provide potable water service within CMWD and portions of the City of Carlsbad not located in other retail water service agencies.

On January 1, 1990, CMWD became a subsidiary district of the City of Carlsbad through an agreement between both agencies approved by the City Council on April 25, 1989.

From 1979 until joining with the City as a subsidiary district, CMWD was known as the Costa Real MWD. The Carlsbad City Council, acting as CMWD’s Board of Directors, governs CMWD. CMWD’s current water supplies consist of treated water purchased from SDCWA, local potable desalinated water received with SDCWA blended supplies, and recycled water. Beginning in 1990, CMWD began serving recycled water within its service area. By 1995, CMWD supplied over 1,000 AFY of recycled water through the implementation of the recycled water system facilities of Phase I. CMWD began implementation of Phase II in 2000, which included the construction of the Carlsbad WRF, improvements to Mahr R eservoir, three new booster pump stations, and 24 miles of additional recycled water pipelines. The Phase III Recycled Water Project, which began construction in 2015 and was completed in 2025, included expansion of the existing Carlsbad WRF and construction of distribution pipelines, storage, and related appurtenances. In April 2016, CMWD’s Board approved an agreement to purchase 2,500 AF of desalinated seawater from SDCWA, which is blended along with the purchased water provided to all member agencies. SDCWA’s supply mix includes desalinated seawater, imported water purchased from MWD (treated at MWD’s Skinner Filtration May 12, 2026
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Plant in Riverside County), and through purchase agreements and exchanges with other agencies. SDCWA supplies delivered to CWMD are also treated at SDCWA’s Twin Oaks Water Treatment Plant in San Marcos and conveyed to CMWD through SDCWA aqueducts.

3.5 Climate Change
Climate change result s in higher temperatures, changes in precipitation, and decreased water supplies, all of which are currently affecting and expected to continue to affect Carlsbad. Impacts of climate change generally include increased water demand, increased risk of wildfire, a greater number of extreme heat days, and the decline or loss of plant and animal species. Climate change also has associated public health impacts. City residents who are already more vulnerable to health challenges are likely to be the most affected by climate change. These vulnerable populations tend to be the young and the old, the poor, and those who are already sick. Increases in extreme heat events can increase the risk of heat -related illness or death, or the worsening of chronic health conditions. Food scarcity and higher food prices from climate change impacts on agriculture can cause increased hunger and reduced availability of nutrition. The increased frequency of natural disasters such as floods, droughts, wildfires, and storm surges can cause injury or death, illness, and increases or shifts in infectious diseases (City of Carlsbad 2024).

3.5.1 Climate Action Plan and Energy
The City of Carlsbad adopted a Climate Action Plan in 2015, which was recently updated in 2024 (City of Carlsbad 2024). The Climate Action Plan in part identifies actions to reduce the City’s greenhouse gas (GHG) emissions that contribute to climate change. According to the 2016 Greenhouse Gas Emissions Inventory, water contributed 1% of emissions and wastewater contributed less than one percent of the total emissions (CMWD 2024). As stated in Appendix C of the Climate Action Plan Update (City of Carlsbad 2024), CMWD’s local potable water distribution energy intensity is 15 kWh/acre -foot and recycled water treatment and distribution energy intensity is 299 kWh/acre-foot. The Climate Action Plan Update identifies actions to reduce GHG emissions, including t hose presented in Table 3-4, which are GHG reduction actions associated with water and wastewater facilities and operations.

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TABLE 3-4: WASTEWATER AND WATER GHG REDUCTION MEASURES
Measure Action
Measure W-1: Wastewater System
Improvements – Focused on
improvements to the wastewater
system.

Primary: Continue making improvements to the City of
Carlsbad’s collection system, including but not limited to upgrading lift stations.

Supportive: Explore system improvements based on the
Supervisory control and data acquisition (SCADA) Master Plan.

Measure W-2: Water System
Improvements – Focused on
improving CMWD’s potable and
recycled water systems to increase
energy efficiency and strengthen the
reliability of local water supplies to
meet community needs.

Primary: Continue making improvements to CMWD’s potable and recycled water systems, including but not limited to expanding water reuse and using renewable energy to power facilities.

Supportive: Continue to explore local water supply options and assess feasibility and cost to benefit ratio.

Source: City of Carlsbad CAP 2024

3.5.2 Climate Change Vulnerability Analysis
As an agency with limited local water supplies and located in a coastal area that could be subject to impacts from sea level rise, climate change is of concern to Carlsbad. In 2023, the City completed a Climate Change Vulnerability Assessment (City of Carlsbad 2023), evaluating how climate change may impact vulnerable community members, natural resources, critical facilities, buildings, services, and infrastructure in Carlsbad, which includes CMWD’s service area. The City anticipates experiencing several significant climate change vulnerabilities across multiple sectors. By 2100, Carlsbad expects to experience more extreme heat days, prolonged droughts, increased high wildfire risk days, increased susceptibility to landslides, worsening air quality, more fre quent flooding, and up to 6.6 feet of sea level rise. Table 3-5 presents the potential climate change impacts to Carlsbad.

TABLE 3-5: POTENTIAL IMPACTS OF CLIMATE CHANGE IN CARLSBAD Impact Expected Effect
Temperature Rise in average maximum temperatures by 3.2° F to 4.0° F by 2050 and by 4.2° F to

7.2° F by 2100
Rainfall Wettest day every year will increase from 10% to 30% by the end of the century with more precipitation occurring during extreme events
Heat Increase in extreme heat days by 22 days and warm nights are expected to increase by 73 nights
Drought Increases in the length of dry spells
Wildfires Increase in high wildfire risk days, frequency, and potential area burned from wildfires
Landslides Greater susceptibility to landslides due to increasing precipitation variability and wildfires increase in frequency, area, and severity
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Impact Expected Effect
Riverine and
Stormwater
Flooding
More frequent flooding in low -lying areas and longer 100 -year-floods due to changes in precipitation patterns
Air Quality Worse air quality in the San Diego region due to increases in wildfires and maximum temperatures
Sea Level Rise Up to 6.6 feet of sea level rise by 2100 Source: City of Carlsbad CAP 2023
The Climate Change Vulnerability Assessment uses a scoring matrix to prioritize vulnerable populations, natural and recreational resources, buildings and facilities, and infrastructure and critical facilities. Each item is evaluated based on the severity and likelihood of impact from a climate hazard (Impact Score) and the ability to adapt to that climate hazard (Adaptive Capacity Score). The Impact Score and Adaptive Capacity Score are then combined to form the Vulnerability Score, ranging from low (1 -2) to high (4 -5) (Table 3-6).

TABLE 3-6: PRIORITIZED CLIMATE CHANGE VULNERABILITY ISSUES FOR

CARLSBAD
Climate Hazard Impact Score Adaptive Capacity
Score
Vulnerability Score
Vulnerable Populations
Extreme Heat High Medium 4-High
Drought High Medium 4-High
Wildfire High Medium 4-High
Riverine and
Stormwater Flooding Medium Low 4-High
Air Quality High Low 5-High
Sea Level Rise High Medium 4-High
Natural and Recreational Resources
Extreme Heat/Warm
Nights High Low 5-High
Drought High Low 5-High
Wildfire High Medium 4-High
Riverine and
Stormwater Flooding High Medium 4-High
Air Quality Medium Low 4-High
Sea Level Rise High Medium 4-High
Building and Facilities
Extreme Heat/Warm
Nights Medium Low 4-High
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Climate Hazard Impact Score Adaptive Capacity
Score
Vulnerability Score
Sea Level Rises Medium Low 4-High
Infrastructure and Critical Facilities
Extreme Heat High Low 5-High
Drought High Medium 4-High
Riverine and
Stormwater Flooding High Low 5-High
Air Quality High Low 5-High
Sea Level Rise Medium Low 4-High
Source: City of Carlsbad CAP 2023
Following identification and prioritization of regional climate change vulnerabilities, the Climate Change Vulnerability Assessment identified programs, plans, and policies that help the community of Carlsbad become more resilient to climate hazards in Table 3-7.

TABLE 3-7: EXISTING PROGRAMS, PLANS, AND POLICIES
Existing and Planned Programs, Plans,
and Policies
Objectives
Extreme Heat and Warm Nights
San Diego County Aging and
Independence Services Cool Zones and Fan
Program
Partnership between San Diego County Aging and
Independence Services and San Diego Gas & Electric
(SDG&E); provides designated cooling centers and
distributes free electric fans to seniors and vulnerable residents without access to air conditioning.

San Diego County Excessive Heat Response
Plan (County of San Diego Health and
Human Services Agency 2021)
The San Diego County Health and Human Services
Agency maintain an Excessive Heat Response Plan that
includes an internal plan for coordinating public health resources during extreme heat events and a public-facing version that offers residents guidance and strategies to reduce heat-related risks.

Carlsbad Cool Zone Program Carlsbad maintains cooling centers for residents during periods of extreme heat.

SDG&E Medical Baseline Allowance
Program (SDG&E 2021)

Provides additional electricity at a discounted rate to customers with a qualifying medical need.

Riverine and Stormwater Flooding, Droughts, and Sea Level Rise Impacts CMWD 2020 UWMP UWMP includes a discussion of climate change impacts on the public water system.

Claude “Bud” Lewis Carlsbad Desalination
Plant
Provides a “drought-proof” source of drinking water to
water utilities throughout the San Diego region.

Olivenhain Municipal Water District
(OMWD) 2020 UWMP
Includes a discussion of climate change impacts on the
public water system.

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Existing and Planned Programs, Plans,
and Policies
Objectives
OMWD Potable Water and Recycled Water
Master Plan
Incorporates findings from the San Diego County Water
Authority’s 2013 climate change analysis to inform water demand projections.

North San Diego Water Reuse Coalition
(NSDWRC)
Partnership between northern San Diego County water
and wastewater agencies working to identify areas with
available wastewater supply and demand for recycled
water, aiming to create a drought-proof source of water and reduce discharge of wastewater to the ocean.

San Diego Integrated Regional Water
Management Plan: Integrated Flood
Management Planning Report (County of
San Diego 2013)
The regional study provides guidance for integrated
flood management and offers planning-level risk analysis and general strategies to support decision-making.

City of Carlsbad Local Coastal Program
Land Use Plan 2019 (Carlsbad 2019)
Provides several land use policies that support sea level rise adaptation efforts.

Agua Hedionda Watershed Management
Plan (City of Vista 2008)
Carlsbad assisted with the development of this plan,
which addresses water quality, habitat, erosion, and
hazard concerns within the watershed.

City of Carlsbad Local Coastal Program
(Draft)
Identifies coastal areas that are more susceptible to
damage from a climate change driven increase in sea
level and includes possible adaptation strategies Carlsbad can implement to prevent future coastal flooding and
erosion.

SANDAG Regional Beach Sand Project Placed 1.5 million cubic yards of beach quality sand on regional beaches in the fall of 2021.

The Carlsbad Opportunistic Sand Program The Carlsbad Opportunistic Sand Program was launched in 2006 to lead the City’s sand acquisition effort.

Wildfire Impacts
Carlsbad Hazard Reduction Program Ensures compliance with AB 38 by requiring inspections of properties in High or Very High Fire Severity Zones
during real estate transactions to verify defensible space and vegetation management standards
Carlsbad Fire Department’s Fire Prevention
Bureau (Carlsbad Fire Department 2022)
Mitigates risks within the community by providing
education about the benefits of proper safety practices and reduction of all types of hazardous conditions.

SDG&E Wildfire Mitigation Plan (SDG&E
2021)
Provides mitigation efforts to reduce risk of and increase wildfire resilience
San Diego County Resilience Review
Report: Wildland Fire (County of San Diego
2019)
Identifies gaps in San Diego County’s approach to
reducing community risk from wildfire.

SDG&E Public Safety Power Shutoff
Notifications and Supportive Services
Operates a notification system to alert customers of
Public Safety Power Shutoff during periods of elevated
wildfire risk.

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Existing and Planned Programs, Plans,
and Policies
Objectives
Multiple Climate Hazard Impacts
San Diego County Multi-Jurisdictional
Hazard Mitigation Plan (County of San
Diego 2018)
Assesses hazards within San Diego County, including
Carlsbad, and identifies mitigation strategies that reduce or eliminate long-term risks to people and property from climate hazards.

San Diego County Emergency Operations
Plan (County of San Diego 2018)
Summarizes an emergency management system which
enables a planned response to a variety of disaster
situations.

Carlsbad You Are Not Alone Program Free service for seniors who live alone and would benefit from a daily check.

City of Carlsbad Emergency Operations
Plan (City of Carlsbad 2021)
Provides protocols to prevent, protect, mitigate, respond, and recover from the effects of disasters.

Ready Carlsbad Business Alliance Promotes business emergency preparedness and supports the continuity of operations and community
recovery.

Carlsbad Emergency Response Team Trains volunteers in basic first aid, light search and rescue, and small fire suppression.

Carlsbad Emergency Operations Center Serves as a centralized hub for coordinating support among fire, police, public works, and other response
agencies, as well as managing public emergency alerts,
evacuations, and shelter operations during large-scale
emergencies.

Habitat Management Plan for Natural
Communities in the City of Carlsbad
Identifies opportunities for the City to work
collaboratively with federal and state wildlife agencies to preserve the diversity of habitat and sensitive biological resources within the City.

Alert San Diego Emergency Notification
System
San Diego County uses a regional notification system to send telephone notifications to residents and businesses within the County impacted by an emergency or disaster.

Carlsbad General Plan Public Safey Element Provides policy direction that supports laws and regulation of future development that will minimize the risk of personal injury, loss of life, property damage, and environmental damage associated with natural and
human-caused hazards.

Source: City of Carlsbad CAP 2023
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4. WATER USE
This section addresses current and projected system water use for CMWD’s service area.

System water use consists of water used by CMWD, water sold to others, and additional water uses and losses. Table 4-1 and Table 4-2 present the historic and current water sales, respectively, including demands from low -income households. Figure 4-1 shows historical, current, and projected water use within CMWD’s service area by use type, with the approximate population within CMWD’s service area (estimated as a percentage of the City of Carlsbad population, based on area).

FIGURE 4-1: HISTORICAL, CURRENT, AND PROJECTED WATER USE (AFY)

4.1 Past and Current Water Use
Historical water use and current water use are based on metering data and includes water used by CMWD customers, along with additional water uses and losses. Table 4-1 presents historical and current potable and non -potable use by customer sector from 2005-2025. The water use sectors are characterized in the description that follows. 0 20,000
40,000
60,000
80,000
100,000
120,000
140,000
0 5,000
10,000
15,000
20,000
25,000
2005 2010 2015 2020 2025 2030 2035 2040 2045 2050
Service Area Population (approx)
Water Use (AFY)
Single Family Multi-Family Commericial Industrial
Institutional Agricultural Landscape Water Loss
Recycled Water Population
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TABLE 4-1: HISTORICAL AND CURRENT WATER USE (AFY) (2005-2025) Water Use Sector 2005 2010 2015 2020 2025
Single Family Residential 9,009 7,965 6,995 7,695 7,254 Multi-Family Residential 1,963 1,769 1,621 1,762 1,862
Commercial 3,695 2,886 2,775 2,098 2,636
Industrial - - 6 19 38
Institutional 162 122 105 102 122
Agricultural 716 374 181 162 145
Landscape 4,214 1,914 1,583 1,528 1,502
Water Loss and Unbilled 1,373 1,094 968 509 903
Recycled Water 1,966 3,500 3,793 3,765 3,708
CMWD’s potable water system serves water to four major sectors 1) Residential (single family and multi -family); 2) Commercial/Industrial/Institutional (CII) (reported as three separate sectors); 3) Agricultural; and 4) Landscape. A brief description of each sector and factors affecting their water use is provided here. Water use by tourism and temporary residents are not explicitly reported in a use category of their own even though they create a substantial demand for water within CMWD’s service area; their impacts are masked within the residential and commercial sectors. A brief narrative of the tourism sector in CMWD’s service area is provided in Section 4.1.3. In addition to potable water, CMWD also provides recycled water to some of its customers. Curre nt and projected recycled water demands are summarized with a detailed discussion of CMWD’s recycled water supplies and demands in Section 6 System Supplies . Table 4-2 presents current potable and recycled water demands of the CMWD customer sectors in 2025.

4.1.1 Single-Family Residential and Multi-Family Residential Residential water use represents the largest water use category for CMWD and includes indoor and outdoor uses for both single-family and multi-family customers. Indoor water use includes sanitation, bathing, laundering, cooking, and drinking, while the majority of outdoor residential water use satisfies landscaping irrigation needs. Other minor outdoor residential water uses include car washing, surface cleaning, and similar activities. Total residential water use is anticipated to increase over time as CMWD’s service area reaches residential buildout, though ongoing and even increased culture of conservation and potential water use restrictions are likely to result in a lower per-capita increase in demand compared to historical growth.

4.1.2 Agricultural
Agricultural water use has been decreasing in Carlsbad for the last two decades and it currently represents a very small portion of CMWD’s water demand. In 1991 CMWD sold 1,744 AF to agriculture. By 2000, the agriculture consumption had declined to 1,204 A F May 12, 2026
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and further dropped to 420 AF in 2010 and 145 AF in 2025. Agricultural demands are projected to remain constant over the planning horizon of this UWMP. The Agricultural sector experiences wide seasonal fluctuations due to weather conditions and timing of the growing seasons, and consists primarily of commercial strawberry and flower fields, and wholesale nursery operations. Several properties that are currently being used for agriculture have the potential to be redeveloped into residential uses. However, the timing of these potential conversions is uncertain and cannot be reliably forecast at this time.

TABLE 4-2: 2025ACTUAL TOTAL USES FOR POTABLE AND NON-POTABLE WATER (AFY)
DWR Submittal Table 4-1 Retail: 2025 Actual Total Uses for Potable and Non-Potable Water Water Code Section 10631(d)(1)
Use Type 2025 Actual Water Use
Level of Treatment When
Delivered
Volume
(AF)
Single Family Potable 7,254
Multi-Family Potable 1,862
Commercial Potable 2,636
Industrial Potable 38
Institutional/Governmental Potable 122
Agricultural Potable 145
Landscape (Potable) Potable 1,502
Distribution System Water Loss (Real + Apparent loss) Potable 863 Other (Unbilled Metered + Unbilled Unmetered) Potable 40 Landscape (Recycled) Non-Potable 3,708
Subtotal Potable 14,462
Subtotal Non-Potable 3,708
Total 18,170
Notes: Actual water demands are based on CMWD’s 2025 billing data and the AWWA water loss audit. Billing data are reported in calendar year. The AWWA water loss audit was completed for FY2025 (July 1, 2024 – June 30, 2025) as the most recent water loss data available. Other potable use includes "unbilled unmetered consumption" as reported in the FY2025 AWWA water loss audit. Temporary potable meters billing category was incorporated into the Single-Family use type. Fire protection billing category was incorporated into the Institutional/ Governmental use type. Non-potable landscape represents recycled water demands, which includes agricultural, commercial, irrigation, and industrial customers. Recycled water demands also include temporary recycled water meters.

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4.1.3 Commercial/ Industrial/ Institutional/ Government Commercial water use generally consists of incidental uses necessary for the operation of a business or institution, such as drinking, sanitation, and landscape irrigation. Major commercial water users include service industries such as restaurants, car wa shes, laundries, recreation and hotels. Statistics indicate that almost 60% of Carlsbad’s employment base is in the commercial sector. This sector is anticipated to grow in the future, as infill development in the Carlsbad Village for commercial and contin ued development in the eastern Business Park area for industrial is implemented, and additional properties are developed to support the City’s growing tourism economy.

Industrial water use consists of a wide range of uses, including produce processing and small-scale equipment cooling, sanitation and air conditioning. Water-intensive industrial uses in Carlsbad, such as electronics manufacturing and biotech research, typically require smaller amounts of water when compared to other water -intensive industries found elsewhere in Southern California, such as petroleum refineries, and canneries.

Institutional water use consists primarily of schools and churches within the service area.

Water use characteristics tend to be similar to commercial uses but based on average daily attendance. Outdoor use also tends to be somewhat higher for landscaped areas and recreational fields. However, many of these areas tend to be metered separately and categorized as irrigation.

4.1.4 Tourism and Temporary Residents
Included in CMWD’s Residential and CII water uses are tourism -related water demands.

With a permanent population estimated at 117,315 in 2024 (Woodard & Curran 2025), the City’s population more than doubles on a monthly basis when considering temporary residents. Visitors are drawn to Carlsbad for its proximity to attractions in San Diego County, Legoland, nearby state beaches, and the general lifestyle that makes Southern California a tourist destination.

The tourism industry in Carlsbad affects water usage by not only the number of temporary residents but also through the expansion of service industries and attractions, which tend to be larger outdoor water users. Tourism peaks during summer months, particularly July and August, but is high throughout the year. The peaking experienced in summer months affects seasonal demand and water system peaking. Population forecasts do not specifically account for tourism; however, tourism is reflected in the economic forecasts and causes per capita use to increase. Tourism can also increase per capita demands because out-of-state tourists are less likely to be as conscientious with their water use as locals. Tourists may not be familiar with water -wise practices (e.g., shorter showers, May 12, 2026
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turning off faucets when brushing teeth) or are in “vacation mode” and not actively aware of their water use. They may also be engaging in inherently water -heavy tourism-based activities.

As home rental options such as VRBO and Airbnb grow in popularity, water use by tourists has been increasingly reflected in CMWD’s residential sector. In 2025, within CMWD’s service area, approximately 2,215 residential units were estimated to be seasonall y occupied by tourists (Woodard & Curran 2025). This number was estimated according to DWR-recommended methods by evaluating hourly advanced meter data of single family and multi-family CMWD customers to determine occupancy rates. Of the 24,403 housing units evaluated, 85% were estimated to be occupied by permanent homeowners, 6% by renters, and 9% were estimated to be seasonally occupied by tourists.

4.1.5 Landscape
Landscape irrigation is the third largest water use in CMWD’s service area, just behind commercial water use, and demands are strongly influenced by seasonal differences and annual rainfall. Development within the City of Carlsbad over the last decade and a half has brought about the creation of large amounts of irrigated areas with various uses, including medians, slopes and parkways, which used 29% potable water (1,502 AF) and 71% recycled water (3,708 AF) in 2025 (see Table 4-2).

The City of Carlsbad adopted a Landscape Manual in November 1990 to assist development applicants and landscape architects in understanding the City’s policies toward landscaping. Specifically, the manual requires that irrigation systems be designed to provide the optimum amount of water for plant growth without causing soil erosion or runoff. At the same time, it requires that landscape design include water conservation and alternative (non-potable) water sources as primary criteria. This manual was updated in 2016 and incorporates Carlsbad Municipal Code Chapter 18.50 – Water Efficient Landscape Ordinance (WELO), among other changes. In May 2010, the City of Carlsbad adopted the WELO in accordance with the State’s Water Conservation in Landscaping Act of 2006 (Assembly Bill 1881), which promotes consistency in landscape regulations among land use authorities throughout San Diego County. The State’s Model Water Efficient Landscape Ordinance (MWELO) was subsequently updated in 2015. The City is in the process of updating this manual to reflect changes in State regulations. The regulations reflect improvements for landscape and irrigation design plans, irrigation technologies, and water management for achievable water savings. Total irrigated land use areas, including roadways and parks, is anticipated to remain relatively constant between 2015 and 2040, decreasing by only 8 acres, or approximately 0.2%.

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Landscape irrigation is also a substantial recycled water use within CMWD’s service area.

Recycled water is regulated by CMWD’s Reclamation Rules and Regulations for Construction of Reclaimed Water Mains (1993) and Mandatory Use Ordinance ( CMWD Water Code Title 3.08.020), the San Diego Regional Water Quality Control Board’s reclamation permits and waste discharge requirements for CMWD’s Carlsbad WRF (Order No. 2001-352, as amended by Order Nos. R9-2012-0027 and R9-2016-0183), and VWD’s Meadowlark WRF (Order No. R9-2007-0018), LWWD’s Gafner WRF (Order No. R9 -2004- 0223), and California’s Title 22 regulations.

Total recycled water use, including golf courses and industrial purposes, represents about 21% of total water use in CMWD’s service area for 2025. Recycled water use tends to be lower in the winter months because of wet weather and less irrigation demand for landscape, the primary use for recycled water. With the recent completion of the Phase III Recycled Water Project, recycled water sales are expected to peak at the delivery capacity, which is estimated at 4,218 AFY. The use of recycled water for landscaping irrigation may increase slightly within CMWD’s service area in response to new requirements. AB 1572 was added to the Water Code (Section 10608.14) in 2023, banning the use of potable water to irrigate non-functional turf. Beginning in 2027, and phasing in over three years, potable water will no longer be allowed to be used for the purposes of irrigating turf grass that is not functionally used for recreational and community purposes. The non-functional turf applies to properties owned by governments o r public agencies, commercial, institutional and industrial properties, and common areas of homeowners’ associations and community organizations. Many of these customer types already use recycled water for landscape irrigation within CMWD’s service area, b ut limited expansion of recycled water for landscape irrigation may still occur. Recycled water use is addressed in greater detail in Section 6 System Supplies.

4.1.6 Additional Water Uses
Additional water uses include fire protection and other authorized uses. Examples include water consumed by CMWD for operations, water main flushing, sewer cleaning, or fire flow tests. CMWD has improved its tracking and documentation of this water through coordination with the City’s Fire Department.

4.1.7 Sales to Other Agencies
CMWD does not currently sell potable water to other agencies, nor does it anticipate doing so in the future; however, water could be sold or supplied to other agencies during emergency SDCWA shutdowns if needed. CMWD has its own local potable water supply through a purchase agreement with SDCWA to purchase desalinated seawater from the Claude “Bud” Lewis Carlsbad Desalination Plant (Carlsbad Desalination Plant) blended May 12, 2026
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with other SDCWA supply. CMWD sells a portion of the recycled water it produces at the Carlsbad WRF to customers of neighboring agencies to help meet their non-potable water demands, but does not sell recycled water directly to any other agency. In 2025, CMWD sold 25.3 AF of recycled water through seven meters (customers) located within the City, but within VWD’s service area.

4.1.8 Distribution System Losses
System losses are water losses through leaks and breaks (referred to as “real” losses).

Losses also include customer metering inaccuracies, data handling errors, and unauthorized consumption (referred to as “apparent” losses), although these losses are relatively small. As required by the 2025 UWMP Guidebook, CMWD completed a water loss audit using the American Water Works Association (AWWA) Water Audit methodology (see Appendix F). Apparent losses (unauthorized consumption and metering inaccuracies) were c alculated as 268 AFY, while Real Losses were calculated at 595 AFY, for a total loss of 863 AFY. Unlike the rest of the data presented in this UWMP, the Water Loss Audit was completed for Fiscal Year 2025, while the rest of the UWMP reports data from calendar year 2025. 2025 water losses are therefore considered approximate. Calculated water losses for CMWD’s water system for the previous five years of reporting are shown in Table 4-3. Based on average annual losses, CMWD anticipates that water losses will represent 5% of total potable use, calculated as the volume of water loss divided by the total volume of water produced. Projected water losses presented in Table 4-8 are estimated using this proportion.

TABLE 4-3: REPORTED WATER LOSS (2020 – 2025)
Reporting Period Volume of Water Loss
(Real + Apparent Losses) (AF)
January 1, 2020 – December 31,2020 470.870
January 1, 2021 – December 31, 2021 578.220
January 1, 2022 – December 31, 2022 841.294
January 1, 2023 – December 31, 2023 635.270
July 1, 2023 – June 30, 2024 762.429
July 1, 2024 – June 30, 2025 863.026
Progress Toward Meeting the Water Loss Performance Standards The SWRCB adopted its Water Loss Performance Standards in 2022, and they became effective in 2023. Under these regulations, retail water suppliers with more than 200 service connections must meet water -loss thresholds that are specific to their individual May 12, 2026
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systems. State compliance evaluations will begin in 2028. In accordance with Water Code Section 10631(d)(3)(C), CMWD must include information in its 2025 UWMP demonstrating whether it achieved its applicable water loss standard. As shown in Table 4-4, CMWD has submitted annual water loss audit reports to DWR for the past five years. The associated AWWA audit worksheets for each reporting year are included in Appendix F.

TABLE 4-4: RETAIL WATER LOSS AUDIT REPORTING
DWR Table 4-5 Retail: Retail Water Loss Audit Reporting Public Water System ID # Reporting Period Submitted to DWR Water Loss Audit Program CA3710005
2020 Yes
2021 Yes
2022 Yes
2023 Yes
2024* Yes
*Fiscal Year July 1, 2024– June 30, 2025
Table 4-5 summarizes CMWD’s progress toward meeting the 2028 performance standards, based on the FY 2025 AWWA Water Loss Audit. For 2028, CMWD’s Real Water Loss Standard is 13 gallons per service connection per day (GPSCD), and its Apparent Water Loss Standard is 8.3 GPSCD. In FY 2024, CMWD reported real losses of 27.2 GPSCD and apparent losses of 8.4 GPSCD. CMWD has not yet achieved its 2028 real loss standard or 2028 apparent loss standard.

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TABLE 4-5: PROGRESS TOWARD 2028 WATER LOSS STANDARD
Submittal Table 4-6 Retail: Progress Towards 2028 Water Loss Standard Water Code Section 10631(d)(3)(C)
Public Water
System ID #
Reported in
Submittal
Table 2-1 R
Did the Water
Board
Calculate a
Water Loss
Standard for
this Public
Water
System? (y/n)
If no, Supplier
will not
complete this
row.

Real Water Loss Apparent Water Loss
SWRCB Standard Most Recent AWWA Water
Loss Audit
Real
Water
Loss
Per
Unit
per
Day
SWRCB Standard Most Recent AWWA
Water Loss Audit
Apparent
Water
Loss Per
Unit per
Day 2028
Real
Water
Loss
Standard
per Unit
per day
Units for Real
Water Loss
Drop down
list
Number of
Units
(Connections or
Miles
corresponding
with units
selected)
Volume
of Total
Real Loss
(from
AWWA
Water
Loss
Audit)
(AF)
2028
Apparent
Water
Loss
Standard
per Unit
per Day
Units for
Apparent
Water Loss
Number of
Connections
Volume of
Total
Apparent
Loss
(from
AWWA
Water
Loss
Audit)
(AF)
CA3710005 Yes 13
Gallons per
Service
Connection
per Day
(GPSCD)
28,283 863.026 27.2 8.3
Gallons per
Service
Connection
per Day
(GPSCD)
28,283 267.585 8.4
Source: Water Board's Calculated Water Loss Standards, available online at:
https://view.officeapps.live.com/op/view.aspx?src=https%3A%2F%2Fwww.waterboards.ca.gov%2Fconservation%2Fdocs%2Fwaterlosscontr ol %2Fstandards-released.xlsx&wdOrigin=BROWSELINK
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4.2 Projected Water Use
This section presents CMWD’s projected potable water use in five -year intervals, from 2030 to 2050, including water used by CMWD customers, water sold to others, and additional water uses and losses. Demand projections presented in the 2025 UWMP are based on CMWD’s monthly consumption reports by customer class from 2014 through 2025, annual water loss audit reports, and the City of Carlsbad local housing units forecast.

The population projections presented in Section 3 System Description incorporate land use changes and other local economic and demographic factors, and provide an appropriate basis for demand projection calculations. Historical demands by customer class and customized potable water consumption growth rates for each customer class were analyzed based on anticipated growth behaviors within the CMWD service area.

Connection types were organized into the same customer class categories as the 2025 UWMP to estimate a long-term growth trend for 2030 through 2050. Growth rates were customized based on each customer class, as shown in Table 4-6. Most growth rates use an average from the past five years (2020- 2025) of consumption. Residential demand projections, however, were based on the City of Carlsbad’s updated local housing unit projections and expected residential buildout by 2035 (See Section 3.1.4). CMWD is assuming maximum population density by 2035 as a conservative estimate when forecasting demand. The residential demand was based on City of Carlsbad local housing unit projections and actual water consumption per housing unit in 2020 and 2025. A proportional allocation method was used to distinguish water use between single -family and multi-family accounts in the residential sector forecast. First, the proportion of multi- family to total residential in the current year was identified (20.4%), then the expected annual growth in the multi -family sector (0.2%) was calculated based on historic (2015- 2025) trends and applied to future annual water consumption in the residential customer class. The remainder of the total future residential water consumption was allocated to the single-family sector.

Agricultural demand was conservatively assumed to stay constant, rather than follow the average trend from the past five years. Historical annual changes in agricultural demand have varied widely and the average from the past five years was negative four percent growth, which, if applied to 2050 projections, would equate to near zero future agricultural demands, which is likely unrealistic. Holding agricultural demand steady allows for a conservative, non-zero demand forecast in this customer class.

Recycled water demands are based on the available recycled water infrastructure and connections available through the Phase III Recycled Water Project. Currently, there are still opportunities to connect new customers, thus a growth rate comparable to the average from the past five years (2020-2025) is assumed; however, it is assumed that these May 12, 2026
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opportunities will be met by 2035 and recycled water demand will be constant through 2050. An annual growth rate of 2% is assumed through 2035.

Water loss as a percentage of total potable demand between 2021-2023 averaged 5%. To meet the 2028 water loss standard, CMWD will reduce its water loss by about half (from 27 to 13 GPSCD). The historic average of 5% was halved (2.5%), then used to calculate future water loss as a percentage of projected potable demands. Likewise, projected unmetered consumption was estimated based on the average percentage of unbilled unmetered consumption to total water supplied, as reported on the AWWA Water Loss audit reports between 2020 and 2025; the average of 0.27% was then used to calculated future unmetered consumption as a percentage of projected potable demands.

TABLE 4-6: GROWTH RATE CALCULATIONS FOR EACH CUSTOMER CLASS Customer Class Projection Growth Rate Growth Rate Calculation Residential 9 - 12% through 2035
then 0% through 2050
Based on housing unit projections from the
City of Carlsbad Planning Department,
which assume buildout and max population
by 2035
Commercial, Industrial &
Institutional (CII) 1%
Average growth rate from the past five
years (2020-2024) for combined connection
types
Irrigation -2% Average growth rate from the past five
years (2020-2024)
Recycled Water 2% through 2035 then 0%
t
hrough 2050
Average growth rate from the past five
years (2020-2024) through 2035 then no
growth because recycled water demands
are expected to use all available
connections and supply availability by 2035.

Recycled water capacity is 4,218 AFY.

Water Loss ---
Half of historic average water loss
percentage (5%) of total potable demand in
order to meet 2028 water loss standard
Unmetered ---
Average unmetered percentage from past
six years (2020-2025): estimated 0.24% of
total potable demand.

Agricultural 0%
Assuming no change compared to average
demand from the past five years (2020-
2024)
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4.2.1 Climate Change Effects on Water Use
As part of the preparation of its Draft 2025 UWMP, SDCWA evaluated the potential impacts of projected climate change on future water demands (SDCWA 2025). Because CMWD receives its potable water from the SDCWA, the SDCWA analysis is informative of what CMWD can expect in terms of plausible changes on projected water use under climate change conditions. The SDCWA analysis uses climate projection data from the LOCA2-Hybrid California dataset to represent a range of future temperature and precipitation conditions. SDCWA evaluated several climate scenarios, which included warmer and wetter, warmer and drier, cooler and wetter, cooler and drier, and moderate conditions, for mid -century (2045-2065) and late century (2080-2100) periods. These scenarios were then applied to SDCWA’s regional water demand model.

Results indicate that warming temperatures are the primary cause of increased water demand, especially for outdoor irrigation, while changes in precipitation have less of an impact. For the mid-century period, projected regional water demand increases by 0.4% to 3.3% compared to historical normal conditions. Under more extreme late -century climate scenarios, the projected demand increases range from 2.1% to 11%. Overall, the results indicate that climate change is expected to gradually increase regional water demand over time, reinforcing the importance of continued water use efficiency and a diversified portfolio to support long-term water supply reliability.

4.2.2 Future Conservation Savings
Passive savings are reflected in CMWD’s water use and incorporated into the demand projections presented in the 2025 UWMP. CMWD is actively encouraging customers to reduce potable water use through the increased use of recycled water, installation of water-wise landscaping, replacement of fixtures with water -saving and low-flow devices, and outreach and educational campaigns. Section 9 Demand Management Measures provides details on CMWD’s efforts to continue its long history of encouraging water conservation. Compliance with applicable regulations and codes requiring use of low-flow fixtures in new construction will result in passive savings.

Base conservation savings associated with Water Shortage Contingency Plan (WSCP) Level 1 are assumed to be integrated into historic use and, therefore, into the demand projections. Over the past five years (2020-2025), CMWD has been in Level 1 for four out of the five years and Level 2 for one. Because the majority of the past five-yea r average was within Level 1 conservation savings, it can be conservatively assumed that a minimum of WSCP Level 1 conservation savings are already included given the conservation mindset and ongoing normal consumption patterns. Additionally, CMWD maintains active WSCP Level 1 implementation even during normal conditions; therefore, it can be May 12, 2026
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assumed that WSCP Level 1 savings will be active through 2050. Further description of conservation savings from the WSCP can be found in Section 8.

TABLE 4-7: INCLUSION IN WATER USE PROJECTIONS
DWR Submittal Table 4-3 Retail: Inclusion in Water Use Projections Water Code Section 10631 (a), 10631 (d)(4)(A), and 10631 (d)(4)(B) Are Future Water Savings Included in Projections? Yes
If "Yes" to above, state the section or page number, in the cell to the right, where citations of the codes, ordinances, etc. utilized in demand projections are found.

Sections 4.2.2 and 5.2
Are Lower Income Residential Demands Included In
Projections? Yes
On June 21, 2005, CMWD’s Board of Directors adopted Ordinance No. 43, now codified in the CMWD Water Code, Title 3. This ordinance, also referred to as CMWD’s Mandatory Use Ordinance, requires customers to use recycled water “wherever it has determined that its use is economically justified, financially and technically feasible, and consistent with legal requirements, preservation of public health, safety and welfare, and the environment.” As a result of this ordinance, new development is prepared to conver t to recycled water for irrigation purposes once recycled water becomes accessible. CMWD’s ability to meet potential customers’ recycled water demands now and in the future has been included in its recycled water use and recycled water supply projections. As recycled water use has increased, CMWD’s per capita potable water use has decreased, helping to achieve its SBx7-7 targets in 2020.

In addition to potable water use savings achieved through conversion to recycled water, CMWD anticipates water savings resulting from compliance with water efficiency regulations. A number of regulatory changes have been made in recent years to encourage or mandate the use of low -flow and efficient plumbing fixtures, along with improvements to building standards to encourage green building that is more water efficient. These changes include, but are not limited to, AB 715 (efficient toilets and urinals) and SB 407 (retrofitting for efficient fixtures). CMWD has successfully taken measures to reduce per capita water use since the Water Conservation Act of 2009 was enacted.

CMWD’s per capital water use was below its SB X7-7 interim target of 233 GPCD in 2015 and its 2020 target of 207 GPCD (see Chapter 5).

New indoor and outdoor water use regulatory standards were developed under SB 606 and AB 1668 and adopted in 2024. Under these regulations, CMWD is required to calculate an annual Urban Water Use Objective (UWUO) using State‑prescribed standards for residential indoor and outdoor water use, commercial, industrial, and institutional (CII) May 12, 2026
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Chapter 4: Water Use 4-14
landscape efficiency, and distribution system water loss. CMWD is required to report its calculated objective and actual water use annually beginning in 2024 to the State Water Resources Control Board, with UWUO compliance evaluated beginning in 2027.

Conservation measures implemented by CMWD, which have helped to meet SB X7 -7 targets and will help to meet its UWUO, include installation of water efficient fixtures and turf replacement, as described in Section 9 Demand Management Measures. New development in CWMD’s service area will be constructed compliant with all applicable codes, and mandatory retrofits will be implemented, as applicable (e.g., dedicated irrigation meters). The reduced water use resulting from these codes and regulations have been incorporated into CMWD’s demand projections because they are reflected in the decreased per capita demands of the SB X7-7 targets. SB X7-7 compliance is discussed in greater detail in Section 5 SB X7-7 Targets and Reporting. Because much of the existing development in the City of Carlsbad is relatively new, many residences, commercial buildings, and other facilities already use lower flow devices, and there are limited opportunities or need to retrofit existing structures to further improve water use efficiency to increase passive savings for existing development. Redevelopment projects in older areas of the city will also incorporate conservation design measures and landscaping.

4.2.3 Water Use for Lower Income Households
CMWD does not keep direct records of which customers are lower income households, but water use associated with lower income households is already incorporated into the overall demand projections for CMWD’s service area. Because these customers are distributed throughout the community and are served through the same retail water system as all other customer classes, their anticipated water needs are inherently reflected in the total residential water demand estimates. See Section 3.1.4 Population and Demographics for additional details on disadvantaged communities.

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TABLE 4-8: TOTAL USES OF POTABLE AND NON-POTABLE WATER - PROJECTED (2030 – 2050)
DWR Table 4-2 Retail: Total Uses of Potable, and Non-Potable Water - Projected Use Type
Projected Water Use (AF)
Level of
Treatment
2030

2035

2040

2045

2050

Single Family Potable 7,897 8,716 8,716 8,716 8,716
Multi-Family Potable 2,128 2,464 2,464 2,464 2,464
Commercial Potable 2,913 3,066 3,226 3,395 3,573
Industrial Potable 38 40 42 44 46
Institutional/Governmental Potable 145 152 160 169 177
Agricultural Potable 163 163 163 163 163
Landscape Potable 1,227 1,136 1,052 974 902
Distribution System Water
Loss (Real + Apparent Loss) Potable 363 393 396 398 401 Other (Unbilled metered +
unbilled unmetered) Potable 41 44 44 45 45
Landscape (Recycled) Non-
Potable 3,898 4,218 4,218 4,218 4,218
Subtotal Potable 14,915 16,174 16,263 16,368 16,487
Subtotal Non-Potable 3,898 4,218 4,218 4,218 4,218
Total 18,813 20,392 20,481 20,586 20,705

4.2.4 Projected Total Water Use and Demand Provided to Wholesaler SDCWA currently provides the majority of potable water distributed by CMWD. The projected amount of water that CMWD expects to purchase from SDCWA to meet water demands in the future is considered in Section 6 System Supplies. Table 4-9 provides a summary of the total projected normal year water demand for CMWD. Estimated changes in demand resulting from single or multiple dry years are provided in Section 7 Water Supply Reliability. CMWD’s current and projected demands on SDCWA potable water are equal to the total potable water demands presented in Table 4-8, less local recycled water supplies and less the 2,500 AFY desalinated seawater that CMWD receives from the Carlsbad Desalination Plant via a Take or Pay agreement with SDCWA.

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TABLE 4-9: TOTAL PROJECTED WATER DEMANDS ON WHOLESALER (AF) 2030 2035 2040 2045 2050
12,415 13,674 13,763 13,868 13,987

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Chapter 5: SB X7-7 Targets and Reporting 5-1

5. SB X7-7 TARGETS AND REPORTING
The Water Conservation Act of 2009 (also known as SB X7-7) was signed into law in November 2009 as part of a comprehensive water legislation package. SB X7-7 set a goal of achieving a 20% reduction in urban per capita water use statewide by 2020. DWR developed technical methodologies to guide the consistent development by urban water suppliers of their baseline per capita water use and targets. These baselines and targets were first reported in the 2010 UWMPs and revised in the 2015 and 2020 UWMPs. The 2025 Guidebook requires that all urban water retailers report their progress in meeting their 2020 target.

5.1 Overview
The reporting requirements for the 2025 UWMP cycle vary depending on whether an urban water supplier was classified as an urban retail water supplier in 2020, met their 2020 target, or underwent a merger or consolidation since 2020:
• Supplier Was Not an Urban Retail Water Supplier in 2020: Urban water suppliers that first met the definition of an urban retail water supplier after 2020 were not subject to SB X7 -7 or UWMP requirements during the 2020 reporting cycle. These suppliers must indicate that they were not an urban retail water supplier during or before the 2020 UWMP reporting cycle. • Supplier Met 2020 Target in 2020: Suppliers that met their 2020 target in 2020 must submit Submittal Table 5-1R and include both their '2020 Target' and '2020 Actual GPCD' to verify compliance with SB X7-7 requirements. This information can be obtained from the supplier’s 2020 UWMP. This reporting requirement is applicable to CMWD.
• Supplier Did Not Meet 2020 Target in 2020 – No Change to Service Area: If a retail supplier did not achieve its 2020 target in 2020 and has had no changes to its service area since then, the supplier must compare its actual 2025 GPCD with the 2020 target to report progress toward meeting that target in its 2025 UWMP.

These suppliers will complete Submittal Table 5-1R to document progress toward the 2020 target in 2025. They must also complete the SB X7-7 2025 Compliance Form to show the calculations used to determine the 2025 GPCD.

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• Supplier Did Not Meet 2020 Target – Change Service Area Since 2020: If a retail supplier did not meet its 2020 target and its service area changed between 2020 and 2025, the supplier must compare its actual 2025 GPCD with the 2020 target to report progress toward achieving that target in 2025. These suppliers must also provide documentation of their SB X7-7 compliance for the service area changes.

CMWD was an urban retail water supplier in 2020, met its 2020 Target in 2020, and has not had any service area changes since 2020. Compliance with the requirements for the 2025 UWMP in relation to SB X7-7 is documented here.

5.2 Water Use and Compliance
In 2010, CMWD established a 2020 per capita water use target equal to 80% of its baseline, calculated using a 10-year period from 1999 to 2008. Because recycled water comprised more than 21% of 2008 retail deliveries (2008 recycled water as a percent of to tal deliveries was 15.9 [CMWD 2011]), the extended baseline was allowed. The baseline was 259 gallons per capita per day (GPCD), resulting in a 2020 target of 207 GPCD. As shown in Table 5-1, CMWD met, and exceeded, its 2020 target in 2020. Because of this, no additional analysis is required for the 2025 UWMP.

TABLE 5-1: SB X7-7 2020 TARGET PROGRESS
DWR Table 5-1: 2020 Target Progress
Was Supplier part
of a merger or
consolidation
since 2020?
Regional Alliance
Target or
Individual Target
2020 Target Actual 2020 GPCD
Did Supplier
Achieve Targeted
Reduction for
2020?
No Individual Target 207 134 Yes
Notes: NA=Not Applicable
DWR and SWRCB have implemented reporting for the AB 1668 / SB 606 legislation, more commonly known as Making Conservation a California Way of Life . Reporting on compliance with this new legislation is not currently required for the 2025 UWMP.

However, in the interest of demonstrating progress towards the new objectives, CMWD’s 2025 GPCD has been estimated at 134 GPCD (total potable water less delive ries to agricultural uses, divided by service area population, then divided by days). CMWD is still in compliance with its target.

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6. WATER SUPPLY
This section discusses CMWD’s sources of water supply, new supply opportunities , exchanges and transfers of water, wastewater and recycled water opportunities, projected water supplies, and climate change impacts to water supply.

6.1 Water Supply Characterization
CMWD’s existing water sources include a local supply of recycled water, a local supply of desalinated seawater, and purchased SDCWA water. All of CMWD’s potable demands are currently met with imported purchased water and desalinated seawater, which are delivered through SDCWA infrastructure. CMWD’s future supplies include the existing recycled water supply from the Phase III Recycled Water Project along with continued potable and desalinated seawater purchases from SDCWA. No additional supplies are currently being planned. The Phase III Recycled Water Project was completed in 2025 and expanded CMWD’s existing recycled water system to increase recycled water production, delivery and storage. Construction of new pipeline segments totaling 97 miles, the Carlsbad WRF expansion to 7 mgd capacity, and a new 1.5 million gallon storage reservoir have been completed as of June 2025. Since late 2016, desalinated seawater made available via the Carlsbad Desalination Plant has been blended into the treated water purchased from SDCWA. On April 12, 2016, CMWD entered into a purchase agreement with SDCWA to receive local desalinated water blended with other SDCWA supplies.

A detailed summary of CMWD’s projected supplies is provided in Section 6.9. An overview of CMWD’s supplies is provided in Table 6-1. Figure 6-1 shows CMWD’s water supply facilities and infrastructure, as well as groundwater basins.

TABLE 6-1: SUMMARY OF HISTORICAL, EXISTING, AND PLANNED WATER

SUPPLIES (AFY)
Source 2020 2025 2030 2035 2040 2045 2050
SDCWA
Purchases
11,375 11,962

12,415

13,674

13,763 13,868

13,987

Seawater
Desalination
2,500 2,500 2,500 2,500 2,500 2,500 2,500
Recycled
Water
3,765 3,708 3,898 4,218 4,218 4,218 4,218
Total Water
Supplies
17,640 18,170

18,813

20,392

20,481

20,586

20,705

Notes: It is assumed CMWD’s contract for 2,500 acre-feet per year of desalinated supply will be renewed when the current contract expires in 2046.

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Chapter 6: Water Supply 6-2
FIGURE 6-1: CMWD WATER SERVICE SYSTEMS

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6.2 Purchased or Imported Water
CMWD purchases all of its potable water from SDCWA, which in turn purchases State Water Project (SWP) and Colorado River water from MWD, acquires Colorado River supplies directly or from other agencies, and purchases desalinated seawater produced at the Channelside Water Resources LP (formerly known as Poseidon Resources) Carlsbad Desalination Plant. Imported water is conveyed into the area via MWD and SDCWA aqueducts (Figure 3-4). Upon its formation in 1954, CMWD joined SDCWA to acquire the right to purchase and distribute imported water throughout its service area. SDCWA has 22 member agencies, including CMWD, and is the regional wholesaler of imported water in San Diego County. In 2016, CMWD entered an agreement with SDCWA to purchase direct deliveries of desalinated seawater, reducing CMWD’s reliance on SDCWA imports for potable supplies (see Section 6.3 Desalinated Water).

CMWD also purchases disinfected tertiary recycled water produced at the Meadowlark Water Reclamation Facility from VWD to help meet CMWD’s recycled water demands.

Further discussion is provided in Section 6.4 Wastewater and Recycled Water.

6.2.1 Metropolitan Water District of Southern California (MWD) MWD was created in 1928 following the passage of the Metropolitan Water District Act by the California Legislature to provide supplemental water for cities and communities on the south coastal plain of California. MWD serves as a water wholesaler and provi des water to its member agencies from both the Colorado River and the SWP. It has 26 member agencies including SDCWA, and covers an area which includes all, or portions, of Ventura, Los Angeles, Orange, Riverside, San Bernardino, and San Diego Counties. MWD’s water supplies and management programs are discussed in its 2025 Regional Urban Water Management Plan (MWD 2025).

6.2.2 San Diego County Water Authority (SDCWA)
SDCWA was organized on June 9, 1944, under the County Water Authority Act for the express purpose of importing Colorado River water into San Diego County. SDCWA annexed to MWD in 1946. As its largest customer, SDCWA is now represented on MWD’s Board of Directors by four directors. SDCWA purc hases water from MWD and other sources for resale to its member agencies. As of 2025, SDCWA’s potable supplies include a mix of imported water and local supplies, including desalinated seawater from the Carlsbad Desalination Plant and local surface water collected at 13 reservoirs.

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CMWD is one of 22 member agencies of SDCWA. Each member agency is autonomous and represented on SDCWA’s Board of Directors, setting local policies and water pricing structures. The representatives on the Board of Directors are appointed by each member agency and the number of representatives for each agency is based on a ratio of each agency’s assessed valuation compared to the total of all member agencies. CMWD currently has two Board members on the 36-member Board of Directors. Member agency status entitles CMWD to directly purchase water from SDCWA on a wholesale basis.

CMWD also looks to SDCWA to ensure, to the best of its ability, that adequate water will be available to satisfy future potable water requirements.

SDCWA’s water supplies and management programs are discussed in its 2025 Urban Water Management Plan (SDCWA 2025). CMWD’s current and projected water purchases from SDCWA are provided in Table 4-9, Table 6-9 and Table 6-10.

6.3 Desalinated Water
Since 1999, a large -scale seawater desalination facility has been actively explored as a potential local supply for the San Diego region. CMWD was involved in planning for the Carlsbad desalination facility throughout its development. After exploring the f easibility of a variety of purchase agreements and delivery structures, Channelside Water Resources LP (formerly known as Poseidon), SDCWA, and SDCWA’s member agencies came to agreement to move forward with implementation of a desalination facility for the region.

In 2015, Poseidon completed construction of the Carlsbad Desalination Plant, located at the Encina Power Plant site adjacent to Agua Hedionda Lagoon, and began deliveries of desalinated seawater at the end of that year. Desalinated water produced at this facility is designated as a local supply, and water from the Carlsbad Desalination Plant is pumped to SDCWA’s Twin Oaks Treatment Plant (refer to Figure 3-4), where it is blended with treated imported water for delivery to SDCWA member agencies, including CMWD.

SDCWA currently purchases all the water produced at the desalination facility under its purchase agreement with Channelside Water Resources. In additi on to receiving desalinated seawater through SDCWA’s supply mix, CMWD also secured its option to receive water directly from the desalinated water conveyance pipeline coming from the Carlsbad Desalination Plant . On April 12, 2016, CMWD Board of Directors approved an agreement between SDCWA and CMWD for the planning and design of the direct connection to the desalinated pipeline (Carlsbad 5 Flow Control Facility and Pressure Reducing Station), to provide 2,500 AFY of local desalinated seawater to CMWD through a Take or Pay agreement. A direct connection would improve water supply reliability and add infrastructure redundancy by providing a delivery system independent of SDCWA’s larger system. Should supply disruption occur as a result of damage to the SDCWA aqueduct system, CMWD would still be able to receive desalinated seawater if and when May 12, 2026
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the option to pursue a direct connection to the desalinated water conveyance pipeline is implemented. Although CMWD has determined that the direct connection (Carlsbad 5 Flow Control Facility and Pressure Reducing Station) is not financially feasible at this time, CMWD has the option to continue pursuing the project in the future should conditions change.

Through its general purchase of water supplies from SDCWA, CMWD receives a pro rata share of 1,449 AFY desalinated water. CMWD also directly receives an additional 2,500 AFY desalinated water as part of a Take or Pay agreement. This supply is considered a local supply for CMWD. In the event that additional water is produced by the Carlsbad Desalination Plant, beyond SDCWA’s annual demand commitment of 48,000 AFY, CMWD may purchase an additional volume of desalinated water, equal to 5.21% of the additional production. This additional water is not accounted for in current supply projections due to uncertainty surrounding its procurement and cost. While the Carlsbad Desalination Plant has a capacity of 56,000 AFY, CMWD only receives a portion through its agreement with SDCWA (see Table 6-2).

TABLE 6-2: S OURCE WATER DESALINATION
DWR Table 6-8ds: Source Water Desalination
Plant Name
or Well ID
Plant
Capacity
Intake
Type
Source
Water
Type
Influent
TDS
Brine
Discharge
Volume of Water Desalinated in AFY
2021 2022 2023 2024 2025
Carlsbad
Desalination
Plant
56,000 Open-
water
Sea
water
.015
ntu Brine Line 2,500 2,500 2,500 2,500 2,500
Total 2,500 2,500 2,500 2,500 2,500
Notes: CMWD purchases ocean desalinated water blended with non-desal water from its wholesaler, SDCWA. NTU is an acronym for Nephelometric Turbidity Unit.

6.4 Wastewater and Recycled Water
The City of Carlsbad, LWWD, and VWD provide wastewater collection services within the CMWD service area, and EWA provides wastewater treatment. CMWD owns the Carlsbad WRF that produces recycled water for its customers. CMWD produces, buys, sells, and distributes recycled water to customers both within its service area and to customers located in an adjacent agency service area. CMWD’s supply projections, in terms of total rights or safe yield, are significantly higher than current identified demands (see Table 6-10) because CMWD has the ability to purchase recycled water from VWD and has also expanded its Carlsbad WRF to increase local production of recycled water. CMWD will either identify new non-potable customers or sell the recycled water to neighboring agencies to allow the region to maximize local sources. CMWD anticipates only producing May 12, 2026
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as much recycled water at Carlsbad WRF to meet demands, but the potential surplus of recycled water allows for flexibility in management of its supplies and provides potential for increasing recycled water use within and adjacent to CMWD’s service area.

6.4.1 Recycled Water Coordination
For production and delivery of recycled water sufficient to meet local demands, CMWD’s recycled water system requires ongoing coordination with EWA and VWD. EWA oversees the regional wastewater collection and treatment system. All wastewater collected within CMWD’s service area is conveyed to the EWPCF, which is owned and operated by EWA.

EWA supplies secondary effluent to the Carlsbad WRF and Gafner WRF (owned and operated by LWWD) for tertiary treatment and discharges unused secondary effluent to the Pacific Ocean via the Encina Ocean Outfall. VWD also produces tertiary recycled water and sells it to CMWD.

6.4.2 Wastewater Treatment and Collection Facilities
EWA provides regional treatment and effluent disposal through an ocean outfall from the EWPCF. EWA is a joint powers authority consisting of six member agencies in northern San Diego County: Cities of Carlsbad, Vista, and Encinitas, VWD, Buena Sanitation District, and LWWD. In total, EWA provides wastewater services to more than 379,000 people and comprises approximately 125 square miles of northern San Diego County (EWA 2025).

Wastewater collected by EWA members is conveyed to the EWPCF, where it is treated to secondary, and either discharged to the Pacific Ocean via the Encina Ocean Outfall or conveyed to the Carlsbad WRF or Gafner WRF for additional treatment for beneficial reuse. The City of Carlsbad owns treatment capacity rights at EWPCF for 10.26 mgd. The EWPCF provides full secondary treatment, sludge handling, and disposal through a deep ocean outfall, the Encina Ocean Outfall. The outfall extends along the ocean floor to a point one and a half miles off shore, at a depth of over 150 feet. Treatment levels at EWPCF meet all current State and Federal requirements. Refer to Figure 6-1 for location of the EWPCF and Encina Ocean Outfall.

Within CMWD’s water service area, wastewater collection is provided by the City of Carlsbad, LWWD, and VWD. The City of Carlsbad’s sewer system includes 273 miles of pipeline and conveyed an average flow of 5.85 mgd for Fiscal Year 2025, a 0.37% increase over 2024 (EWA 2025). LWWD provides wastewater services to the La Costa portion of CMWD’s service area and operates approximately 200 miles of pipeline serving 60,000 people across Carlsbad and neighboring Encinitas (LWWD 2026). LWWD’s flows to the EWPCF averaged 3.78 mgd in Fiscal Year 2025, unchanged from 2024 (EWA 2025). All sewer flows are conveyed to the EWPCF for treatment. VWD provides wastewater services May 12, 2026
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to 80 homes in the southeast corner of CMWD’s service area. VWD flows to EWPCF averaged 4.55 mgd in Fiscal Year 2025, a 0.57% increase over 2024 (EWA 2025).

Wastewater is a supply for recycled water. Table 6-3 identifies the wastewater collected within CMWD’s service area, while Table 6-4 identifies the volume of wastewater that is either recycled or discharged within CMWD’s service area. Recycled water is presently supplied to CMWD customers from two sources consisting of a maximum allocation of

7.0 mgd from Carlsbad WRF and 3.0 mgd from M eadowlark WRF (owned by VWD).

Meadowlark WRF can produce up to 5.0 mgd tertiary recycled water, or 5,600 AFY. CMWD is in the process of negotiating a new recycled water purchase agreement with VWD, under which purchase volumes are anticipated to change.

Encina Water Pollution Control Facility
The EWPCF is owned and operated by EWA. It currently treats an average flow of 20 mgd wastewater, but has the capacity to treat up to 40.5 mgd. The EWPCF produces over 5.0 mgd of secondary treated recycled water. Treated secondary recycled water is used in the plant and reduces costs for potable water required to operate the facility. Additional effluent flows from the facility are diverted from the ocean outfall and transferred to Carlsbad WRF for tertiary treatment. Secondary effluent that cannot be reuse d, either directly or through additional treatment to meet tertiary recycled water demands, is discharged through the Encina Ocean Outfall. In fiscal year 2024-2025, the EWPCF treated a total of 7.97 billion gallons of water (24,459 AF) and recycled 2.9 billion gallons of water (8,900 AF) for onsite use and regional irrigation (EWA 2025).

Carlsbad Water Recycling Facility
The Carlsbad WRF, owned by CMWD but operated by EWA staff, can produce 7.0 mgd (7,839 AFY). On average over the past five years, the Carlsbad WRF produced 3, 708 AFY of recycled water (CMWD 2025). This facility receives secondary treated water from the EWPCF for tertiary treatment.

Meadowlark Water Reclamation Facility
Meadowlark WRF is owned and operated by VWD and has a total capacity of 5.0 mgd.

Currently, CMWD’s rights to disinfected tertiary water from the Meadowlark WRF range from 2.0 mgd during the months of December through March and 3.0 mgd during the months of April through November and equates to 2,989 AFY. The remaining amount of recycled water produced by the Meadowlark WRF is sold to OMWD under an agreement up to a maximum of 1.0 mgd or 1,120 AFY. CMWD generally purchases approximately 1,900 AFY recycled water from Meadowlark WRF, although the Meadowlark WRF has been May 12, 2026
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out of service since December 2024 for plant upgrades which will increase the production capacity up to 6,200 AFY recycled water. CMWD is currently negotiating an agreement that would allow it to receive 2,700 AFY of recycled water from Meadowlark WRF in future years.

Gafner Water Reclamation Facility
The Gafner WRF is owned and operated by LWWD and has a total capacity of 1.0 mgd.

Although CMWD does not purchase recycled water from the Gafner WRF, the plant is located within CMWD’s water service boundary. LWWD sells and delivers directly to the southern portion of the Omni La Costa Resort & Spa golf course, which is within the southern portion of CMWD’s service area.

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TABLE 6-3: W ASTEWATER COLLECTED WITHIN CMWD WATER SERVICE AREA IN 2025 DWR Table 6-2 Retail: Wastewater Collected Within Service Area in 2025 Water Code Section 10633(a)
100% Percentage of 2025 service area covered by wastewater collection system 100% Percentage of 2025 service area population covered by wastewater collection system Wastewater Collection Recipient of Collected Wastewater Name of Wastewater Collection
Agency
Wastewater
Volume
Metered or
Estimated?
Volume of
Wastewater
Collected in
2025 (AFY)
Name of Wastewater
Treatment Agency Receiving
Collected Wastewater
Treatment Plant Name
Is
WWTP
Located
Within
UWMP
Area?
Is WWTP
Operation
Contracted
to a Third
Party?
City of Carlsbad Metered 6,918 Encina Wastewater Authority Encina Pollution Control Facility Yes Yes Leucadia Wastewater District (LWWD) Estimated 968 Encina Wastewater Authority Encina Pollution Control Facility Yes Yes Vallecitos Water District (VWD) Estimated 20 Encina Wastewater Authority Encina Pollution Control Facility Yes Yes Total Wastewater Collected from Service Area in
2025: 7,906
Notes: The Encina Pollution Control Facility is owned and operated by the Encina Wastewater Authority, a joint powers authority that is owned by six agencies, including City of Carlsbad, LWWD and VWD. Wastewater flows are reported for Calendar Year 2025, ending December 31, 2025. LWWD serves a portion of CMWD's service area. The 968 AF for Leucadia was obtained from EWA reports. VWD collects wastewater for 80 homes in the CMWD service area. The agreement estimates VWD collects 220 gallons per day of wastewater from each home.

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TABLE 6-4: W ASTEWATER TREATMENT AND DISCHARGE WITHIN CMWD WATER SERVICE AREA IN 2025 DWR Table 6-3 Retail: Wastewater Treatment and Outcomes Within UWMP Service Area in 2025 Water Code Section 10633(a)
Wastewater
Treatment
Plant Name
Plant Treats
Wastewater
Generated
Outside the
UWMP
Service
Area?
2025
Volume of
Wastewater
Received
from
UWMP
Service
Area
Total
2025
Volume
of
Waste-
water
Treated
2025 Outcomes of Treated Wastewater (volume in AF)
Water
Recycled
Within
UWMP
Service
Area
Water
Recycled
Outside of
UWMP
Service
Area
Effluent
Discharge that
is not a
Permitted
Recycled Water
Use
Required
Discharge
for
Instream
Flow
Delivered to Another Entity for
Additional Treatment
Volume
(Treatment
level)
Volume
(Treatment
level)
Volume
(Treatment
level)
Volume
(Treatment
level)
Volume
(Treatment
level)
Name of Entity
Encina Water
Pollution
Control
Facility
Yes 7,906 28,047 0 6,4 18
(Tertiary)
21,629
(Secondary,
Undisinfected)
0 5,751
(Tertiary)
Carlsbad WRF
Gafner WRF
Carlsbad WRF No 0 5,356 3,683
(Tertiary)

25.3 (Tertiary) 0 0 0
Gafner WRF Yes 0 413 251
(Tertiary) 0 162 0 0
Meadowlark
WRF Yes 0 0 0 0 (Tertiary) 0 (Secondary,
Undisinfected) 0 0
Total 7,906 33,816 3,934 6,443 21,791 0 5,751
Notes: Meadowlark WRF has been non-operational since December 2024, but is expected to resume operations summer 2026.

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6.4.3 Recycled Water Master Plan
CMWD completed an update to its Recycled Water Master Plan in July 2019. The Recycled Water Master Plan evaluates the existing recycled water system, demands, supplies, regulations, and future system expansions. Beginning in 1990, CMWD began implementation of recycled water within its service area. By 1995, CMWD served over 1,000 AFY of recycled water through the implementation of the recycled water system facilities of Phase I. CMWD began implementation of Phase II in 2000, which included the construction of the Carlsbad WRF, improvements to Mahr reservoir, three new booster pump stations, and 24 miles of additional recycled water pipelines. CMWD implemented its Phase III Recycled Water Project between 2014 and 2025, which expanded the Carlsbad WRF capacity, installed additional recycled water pipelines, connected customers along existing recycled water pipelines to recycled water service, and added an additional recycled water storage tank.

6.4.4 Recycled Water Use
CMWD began delivering recycled water in 1993. Since 1993, CMWD has constructed treatment facilities, pumping stations, reservoirs, pipelines, and has adopted a mandatory use ordinance requiring developers to install recycled water distribution pipelines within their projects. Water recycling is provided by CMWD from its Carlsbad WRF to developed areas within CMWD’s service area, with the exception of the south portion of the Omni La Costa Resort & Spa golf course, which is served by LWWD. As described above and identified in Table 6-3, recycled water is presently supplied within CMWD’s service area from three sources: Carlsbad WRF, Meadowlark WRF, and Gafner WRF. The maximum flow rate available to CMWD from each treatment facility varies.

CMWD’s current recycled water system has approximately 97 miles of recycled water distribution pipelines, as shown Figure 6-1. The largest and/or most recognized customers currently served recycled water by the Carlsbad WRF include the following.

Uses are for landscape irrigation, with the exception of NRG:
• Omni La Costa Resort & Spa North Golf Course
• Four Seasons Resort at Aviara
• Kemper Sports Management (Carlsbad Municipal Golf Course) • Legoland of California
• Grand Pacific Palisades Hotel
• Karl Strauss Brewery
• Caltrans (Interstate 5 landscaping)
• The NRG Power Plant (for industrial purposes [e.g., cooling towers] and landscape irrigation)
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In addition, recycled water is supplied to parks, median strips, shopping areas, the common areas of numerous homeowners’ associations, and industrial parks. As of December 2025, this distribution system currently supplies more than 1,015 recycled connections (CMWD 2026). With the completion of the Phase III Recycled Water Project in 2025 (see below), CMWD projects a total of 4,218 AFY recycled water demands beginning in 2035 and into the future. This includes only verifiable recycled water supplies, consistent with SDCWA’s demand projections, but does not include planned or conceptual recycled water projects. There is potential for future projects to expand recycled water demands and deliveries beyond this volume. Recycled water use (current and projected) is presented, by use category, in Table 6-5.

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TA
BLE 6-5: C URRENT AND PROJECTED RECYCLED WATER DIRECT BENEFICIAL USES WITHIN SERVICE AREA 2025-2050
Submittal Table 6-4 Retail: Recycled Water Direct Beneficial Uses Within Service Area Water Code Section 10633 (c)(e)
Name(s) of Facility/ies Producing (Treating) the Recycled Water (OPTIONAL): Carlsbad WRF, Meadowlark WRP, Gafner WRF Name of Supplier Operating the Recycled Water Distribution System (OPTIONAL):

Carlsbad Municipal Water District
Supplemental Water Added in 2025 (volume) Include units (OPTIONAL): 0 AFY Source of 2025 Supplemental Water (OPTIONAL): N/A
Use Type
Water Type
(after
treatment if
treated)
(OPTIONAL)
Additional
Information
(as needed)
2025 2030 2035 2040 2045
2050
(opt)
Potential Recycled
Water Use
(AF) (AF) (AF) (AF) (AF) (AF) Volume
Narrative
page
number
(OPTIONAL)
Landscape irrigation
(excludes golf
courses)
Non-
potable
Commercial
property
irrigation,
community
facilities,
highways, HOAs,
resort property
irrigation, parks,
and schools
2872 3062 3382 3382 3382 3382 0
Golf course
irrigation
Golf course
irrigation 808 808 808 808 808 808 0
Commercial Use Cooling 0 0 0 0 0 0 0
Industrial Use NRG Power Plant 28 28 28 28 28 28 0
Total 3,708 3,898 4,218 4,218 4,218 4,218 0
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6.4.5 Potential and Projected Recycled Water Use
Actual recycled water use in 2025 within CMWD’s service area was 3,708 AFY. The 2020 UWMP projected recycled water use in 2025 was 4,218 AFY. The difference is accounted for by delays in construction and implementation of the Phase III Recycled Water Project, variations in rainfall and temperatures, and general implementation of drought tolerant landscaping which has lower irrigation demands compared to turf. Table 6-6 compares the projected recycled water use for 2025 (as projected in the 2020 UWMP) with actual metered recycled water use in 2025. While recycled water use is anticipated to grow, the exact number of future recycled water connections is unknown. As such, projections in this 2025 UWMP represent the best estimate based on current information, with the understanding that actual recycled water use may be different from the forecast.

TABLE 6-6: 2 020 RECYCLED WATER USE PROJECTION COMPARED TO 2025

ACTUAL (AFY)
DWR Table 6-5 Retail: 2020 UWMP Recycled Water Use Projection Compared to 2025 Actual Use Type 2020 Projection for 2025 2025 Actual Use
Agricultural irrigation
Landscape irrigation (excludes golf
courses) 3,493 2,872
Golf course irrigation 725 808
Commercial Use 0 0
Industrial Use 0 28
Geothermal and other energy production
Seawater Intrusion Barrier
Recreational impoundment
Wetlands or wildlife habitat
Groundwater recharge (IPR)
Reservoir water augmentation
Direct potable reuse
Other 0
Total 4,218 3,708

6.4.6 Methods to Encourage Recycled Water Use
CMWD has actively pursued recycled water use in its service area and has implemented multiple mechanisms to encourage recycled water use. Some of these mechanisms include affordable rates, policies and ordinances, development of clear use guidelines, May 12, 2026
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participation in regional training and certifications, and active participation in regional and local recycled water projects that include outreach and expanded distribution systems. Now that the Phase III Recycled Water Project is complete, CMWD does not expect substantial increases in recycled water use, with the exception of connecting some additional customers along recently constructed pipelines. CMWD considers its recycled water system to generally be at build-out unless substantial land use changes o ccur or regulations change that would result in an increased demand for recycled water, requiring significant capital investment in distribution system expansion, therefore, DWR Table 6-6 is not applicable.

6.5 Local Groundwater and Local Surface Water
As previously detailed in Section 3.4, CMWD does not currently use any local groundwater and surface water supplies, although in the past both types of water sources were used.

Prior to 1957, CMWD’s predecessor, the Carlsbad Mutual Water Company, and the Terramar Water Company provided the City of Carlsbad with water from Lake Calavera and groundwater from the Mission Basin. The Terramar Water Company also provided local groundwater to a portion of the City of Carlsbad through its Cannon Well Field in the Agua Hedionda area. In August 1957, the water rights and other assets of the Carlsbad Mutual Water Company and Terramar Water Company were purchased by the City of Carlsbad. These local groundwater and surface water rights were later transferred to CMWD in 1983. These rights included long-standing groundwater allocations from the Mission Basin, totaling 3,650 AFY through a combination of historic, prescriptive, and pre- 1914 appropriative rights.

The Carlsbad Mutual Water Company held a permit with the State Division of Water Rights for another 1,000 AFY from the Mission Basin, originally for irrigation and later amended for recreational and fire-protection purposes. Additionally, there were surface water rights for 150 AFY which were held from Calavera Creek. The Terramar Water Company had 450 AFY of groundwater rights from the Agua Hedionda Creek Basin. Finally, CMWD obtained a permit for surface water in the amount of 25 AF from Agua Hedionda Cre ek as a result of constructing Maerkle Dam in 1962.

Table 6-7 identifies the groundwater basins in the vicinity of CMWD according to DWR Bulletin 118, which are also shown in Figure 3-4 and Figure 6-1. Of these basins, only the Batiquitos Lagoon Valley Groundwater Basin is in CMWD’s service area, while the San Luis Rey Valley Groundwater Basin is located north of CMWD, and the San Marcos Valley Groundwater Basin is located east of CMWD. Under the California Groundwater Elevation Monitoring (CASGEM), only the Upper San Luis Rey Valley has been designated as Medium Priority Basin and therefore subject to mandatory monitoring, whereas the Lower May 12, 2026
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San Luis Rey Valley and San Marcos Valley basins are designed Very Low Priority and not required to be monitored. Monitoring of the Upper San Luis Rey Valley Basin is conducted jointly by the City of Oceanside, the Pauma Valley Groundwater Sustainability A gency, and the County of San Diego. None of the basins listed in Table 6-7 are adjudicated, nor has DWR identified any of these groundwater basins as being in overdraft. Within the San Luis Rey Valley Groundwater Basin are several locally -recognized subbasins, which are commonly considered separate hydrological units: Mission, Bonsall, Moosa, Pala, and Pauma Basins (SDCWA 2010).

Other groundwater resources include subsurface flows from local hydrologic areas within the Carlsbad Watershed, including Buena Vista Creek Basin, Agua Hedionda Creek Basin, Encinas Creek Basin, and the Batiquitos Hydrologic Subarea. Overall, these areas do not have the geological capacity or scale of the Mission Subbasin in the Lower San Luis Rey Valley Groundwater Basin and, even collectively, could provide only a small portion of CMWD’s overall water needs.

TABLE 6-7: GROUNDWATER BASINS IN THE VICINITY OF CMWD
Basin Name
DWR
Basin
Number
Basin
Priority1
Located
Within
CMWD
Service
Area
Supply
Currently
Utilized by
CMWD
Groundwater Management Plan Status
Lower San Luis
Rey Valley
(including the
Mission Subbasin)
9-7-2 Very Low No 0 AFY
Groundwater Sustainability Plan under
development by Pauma Valley
Groundwater Sustainability Agency
Batiquitos Lagoon
Valley 9-22 Very Low Yes 0 AFY None2
San Marcos Area 9-32 Very Low No 0 AFY None2
1 California Sustainable Groundwater Elevation Monitoring (CASGEM) designated priority 2 Basin is not currently used as supply and no groundwater management plan has been developed or adopted by CMWD. Groundwater management plans or groundwater sustainability plans would be adopted prior to use of these groundwater basins for supply, as required.

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Mission Subbasin
Of the groundwater basins in the vicinity of CMWD, the Mission Subbasin of the Lower San Luis Rey Valley Groundwater Basin has the most potential as a viable water resource.

This basin has a large drainage area of 565 square miles and consists of alluvium and river channel deposits averaging 150 feet in depth. The quality is mildly brackish with TDS concentrations ranging from 1,000 to 1,500 milligrams per liter (mg/L). For CMWD’s use, the water would need to be treated by a low-pressure membrane, reverse osmosis process to achieve treated water quality in the range of 500 mg/L. The City of Oceanside is currently doing this at its Mission Basin Groundwater Purification Facility and is also implementing the Pure Water Oceanside project which recharges the basin with advanced treated water.

In 2005, CMWD completed a study on the cost effectiveness of utilizing the groundwater from the Mission Subbasin. This study showed that while the treatment and delivery of groundwater is feasible, it was not cost effective for CMWD at the time of the study. As a result, CMWD’s Board approved the staff recommendation to discontinue efforts to utilize this groundwater source as an alternate local supply at that time. However, since 2005, improvements in technology may have resulted in lower costs for removing TDS, and these costs may continue to decrease over time. In addition, the cost of imported water has increased significantly since 2005 and this trend is projected by both MWD and SDCWA to continue over time. With the increasing cost and decreasing reliability of imported water, the cost effectiveness of using local groundwater may become attractive in the future. A groundwater supply from the Mission Subbasin would require the construction of several wells, a groundwater treatment facility, and a conveyance system.

Wheeling the treated groundwater through the Oceanside distribution system may be an option. In addition, the State of California does not currently recognize CMWD’s water rights in the Mission Subbasin, and formal water rights would need to be reestablished before any groundwater development could proceed. Accordingly, CMWD will continue to monitor the benefits and costs of utilization of groundwater in the Mission Subbasin, which may become cost effective, for CMWD or third parties, as technology continues to improve and imported water costs continue to increase. A partnership with City of Oceanside for treatment of brackish groundwater or wheeling the treated groundwater through its distribution system may be an option. The Mission Subbasin pr oject is not being considered at this time but could be explored again in the future as CMWD continues to coordinate with City of Oceanside.

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Cannon Well Field
The Cannon Well Field, located within the Agua Hedionda Creek Basin subarea of the Carlsbad Watershed, was historically used as a source of local water. Pumping ceased after 1962, but in the years leading up to then, production ranged from 16 AFY to 238 AFY. This well field could be considered as having a potential available yield of 450 AFY. Historically, additional small private wells for individual residences were also located within this subarea, along with private wells in the Buena Vista Creek Basin (CMWD 2019).

A 1991 study titled Report on the Feasibility for Development of the Cannon Well Field Carlsbad, California was completed for the Agua Hedionda subunit where the Cannon Well Field is located. This study indicated that by a 1950 agreement between then - landowner Ellen Hall and J.D. Cannon, the Terramar Water Company was granted the right to drill for and remove water from the land. In 1964, this original agreement was merged with an agreement with the City of Carlsbad and the then -landowner to have the sole right and exclusive right to drill wells on the property and take and remove all water developed on the property and deliver it to such places as the City, in its sole discretion, may determine. The City (CMWD) shall be entitled to produce from the property an additional 16.5 AFY; however, there are no recorded groundwater rights. The safe yield was estimated in the 1991 study at 400 AFY. CMWD could begin the process of developing the groundwater. The Rancho Carlsbad Mobile Home Park has one operating well in the vicinity, estimated at 100 AFY, which it uses to supply water for irrigation of their landscaping and through a separate agreement to supply water to the adjacent Rancho Carlsbad Golf Course. Ultimately, if there is excessive pumping, there may be adverse effects, such as the elimination of surface flow in Agua Hedionda Creek, reduction in the wetlands area downstream of the El Camino Real Bridge, and increased salinity in the transition zone of fresh water to salt water in the Agua Hedionda Lagoon. These problems can be addressed if the Cannon Well Field is developed by CMWD through a program of scheduled observations and monitoring.

CMWD must clarify and/or re -establish its groundwater rights before providing groundwater to customers. Groundwater could potentially be recovered from the Mission Basin and/or Agua Hedionda Lagoon, although such groundwater would require desalination. CMWD may still explore groundwater as a local water supply concept; as such, groundwater is not included in CMWD’s supply projections. CMWD does not currently pump groundwater; therefore, DWR Table 6-1 is not currently applicable.

6.6 Supply from Storage
CMWD owns and operates Maerkle Reservoir, a 17-acre reservoir that was built in 1962 and is in eastern Carlsbad, near the borders of the Cities of Oceanside and Vista. Maerkle May 12, 2026
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Reservoir can store 600 acre -feet of purchased water from the SDCWA for operational use. Emergency supplies are discussed in Chapters 7 and 8.

6.7 Stormwater
CMWD does not currently utilize stormwater as a water supply source. However, the City of Carlsbad actively promotes rain barrels and rain gardens through its Environmental Sustainability Department. Homeowners are responsible for the installation of greyw ater and rainwater collection systems. CMWD will continue to monitor the development of funding opportunities and best practices by which to pursue stormwater reuse projects in the future.

6.8 Exchanges and Transfers
CMWD relies on potable and desalinated water purchased from SDCWA for potable water supplies, and does not participate individually in any potable water transfer or exchange programs, except as needed during SDCWA shutdowns or emergencies. CMWD may provide recycled water via transfers or exchanges to other agencies in the future as part of the NSDWRC, a nine-agency regional recycled water system, described in further detail in Section 6.9 Projected Water Projects, below. In addition, CMWD has informal agreements with neighboring agencies for emergency purposes only that are not considered in CMWD’s normal supplies. These interties would only be needed in rare emergency events or planned maintenance. Emergency interties are discussed in Chapters 7 and 8.

6.9 Projected Water Projects
The Water Code requires urban water suppliers to describe all water supply projects and programs that the supplier may implement to meet projected water demand.

Recycled Water
CMWD has completed the Phase III Recycled Water Project, which involved expansion of the capacity of the Carlsbad WRF to 7.0 mgd, construction and retrofit of pipelines to deliver recycled water and completion of a 1.5 million gallon recycle water storage tank.

CMWD continues to connect more recycled water customers in new developments or convert existing potable demands to recycled water as opportunities arise and infrastructure supports.

CMWD is one of nine member agencies of the NSDWRC, which is cooperatively implementing a regional recycled water system to maximize recycled water use and implement potable reuse in northern San Diego County. CMWD’s portion of the NSDWRC May 12, 2026
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Regional Project is the Phase III Recycled Water Project. Through the NSDWRC, CMWD may provide recycled water to other members, and may receive additional recycled water from other members, as necessary.

North County One Water
Building on over a decade of collaborative efforts in the region by the NSDWRC, EWA and SEJPA have been working with multiple local water agencies to develop the North County One Water Program. It is currently in the feasibility planning phase. The wastewater flows and facilities from two coastal treatment facilities in North San Diego County, the EWPCF and the San Elijo Water Reclamation Facility (SEWRF), represent a unique opportunity for large-scale production of purified water. The EWPCF in the City of Carlsbad could accommodate an advanced water purification facility. The EWPCF has key assets available for production of purified water such as an ocean outfall, available land for advanced treatment, treated secondary effluent and technically capable staf f. The SEWRF in the Cardiff area within the City of Encinitas, California could also accommodate an advanced water purification facility. The SEWRF also has key assets available for production of purified water such as an ocean outfall, available land for advanced treatment, treated secondary effluent and technically capable staff. The program was estimated to supply an estimated 18,000 AFY to 35,000 AFY. Although cost estimates for infrastructure and water rates are considered prohibitive now, the program could be developed in the future if conditions change. Because the North County One Water Program is still in the planning stages, it is not quantified as a future water supply in Table 6-8.

Groundwater
Potential groundwater supplies are still considered uncertain, and are not quantified in Table 6-8, which presents reasonably available volume of future water supplies. Despite this uncertainty, CMWD will reassess the benefits and costs of developing its groundwater rights in the future, which could help to offset CMWD’s demands on SDCWA for potable water. This addition of groundwater to CMWD’s supply portfolio could strengthen its supply reliability and help reduce CMWD’s reliance on imported supplies.

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Desalinated Water
As noted previously, CMWD’s Board approved an agreement with SDCWA to construct a direct connection to the desalinated water conveyance pipeline. Development of this supply would have involved implementation of the Carlsbad 5 Flow Control Facility and Pressure Reducing Station project. If constructed, CMWD would own and operate the Pressure Reducing Station component, while the flow control facility would be owned and operated by the SDCWA. Although CMWD will continue to receive desalinated water through SDCWA’s supply mix of other potable water sources in accordance with the Take or Pay agreement, CMWD is not pursuing the implementation of the Carlsbad 5 Flow Control Facility and Pressure Reducing Station project at this time due to constraints associated with a suitable site for the facilities, land availability , and the high cost of desalinated water . T herefore, the project to construct a direct connection to the desalinated water conveyance pipeline is not quantified in Table 6-8.

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TABLE 6-8: E XPECTED FUTURE WATER SUPPLY PROJECTS OR PROGRAMS DWR Table 6-7 Retail: Expected Future Water Supply Projects or Programs Water Code Section 10631(f)
No expected future water supply projects or programs that provide a quantifiable increase to the agency’s water supply. Supplier will not complete the table below.

Some or all of the supplier’s future water supply projects or programs are not compatible with this table and are described in a narrative format.

N/A Provide page location of narrative in the UWMP
Name of Future
Projects or
Programs
Joint Project with other agencies?
Description
Planned
Implementation
Year
Planned for
Use in Year
Type
Expected Increase in
Water Supply to
Agency (AFY) Y/N Agency Name
Groundwater Supply No Development of
groundwater supplies -- Average Year Unknown at this
time
NSDWRC Regional
Project Yes
Leucadia Wastewater District,
Vallecitos Water District, City of
Oceanside, City of Escondido,
Olivenhain Municipal Water
District, Rincon del Diablo
Municipal Water District, San Elijo
Joint Powers Authority, Santa Fe
Irrigation District, and Vista
Irrigation District
Regional recycled
water project -- Average Year
Supports
implementation of
Phase III recycled
water project
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Chapter 6: Water Supply 6-23

6.9.1 Summary of Existing and Planned Sources of Water
CMWD’s supplies include SDCWA water (treated SWP and Colorado River, SDCWA surface water, along with desalinated seawater, purchased as a blend from SDCWA), recycled water, and could include groundwater in the future. Current water supplies for CMWD during 2025 are presented in Table 6-9. Projected supplies for CMWD are presented in Table 6-10 and include water supply projects that are underway or in development, along with projected population growth and supply availability from SDCWA.

TABLE 6-9: W ATER SUPPLIES – ACTUAL
Submittal Table 6-8 Retail: Water Supplies — 2025 Actual Water Code Section 10631 (b)
Water Supply
Additional
Description
(as needed)
2025

May use each category
multiple times. These
are the only water
supply categories that
will be recognized by
the WUE data online
submittal tool
Water Type
(after treatment
if treated)
(OPTIONAL)
Actual Volume
Total Entitlement
(OPTIONAL)
See "DWR Notes" below
(AF) (AF)
Purchased or Imported
Water
Purchased from
SDCWA Drinking Water 11,962 11,962
Purchased Local Water
(Desal)
Purchased from
SDCWA Drinking Water 2,500 2,500
Recycled Water Carlsbad WRF Recycled Water 3,708 7,839 Recycled Water Meadowlark WRF Recycled Water 0 2,700 Subtotal Potable 14,462 14,462
Subtotal Non-Potable 3,708 10,539
Total 18,170 25,001
DWR NOTES: Total Entitlement: e.g., Water Right, Groundwater Allocation, Contracted Amount.

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TABLE 6-10: WATER SUPPLIES – PROJECTED
DWR Table 6-9 Retail: Water Supplies — Projected (Water Code Section 10631 (b)) Water
Supply
Additional
Detail on
Water Supply
Projected Water Supply (Report To the Extent Practicable) 2030 2035 2040 2045 2050
Reasonably
Available
Volume
Total
Right or
Safe Yield
(optional)
Reasonably
Available
Volume
Total
Right or
Safe Yield
(optional)
Reasonably
Available
Volume
Total
Right or
Safe Yield
(optional)
Reasonably
Available
Volume
Total Right
or Safe
Yield
(optional)
Reasonably
Available
Volume
Total
Right or
Safe
Yield
(optional)
Purchased
or
Imported
Water
Purchased
from SDCWA 12,415 12,415 13,674 13,674 13,763 13,763 13,868 13,868 13,987 13,987 Recycled
Water Carlsbad WRF 1,198 7,839 1,518 7,839 1,518 7,839 1,518 7,839 1,518 7,839 Recycled
Water
Meadowlark
WRF 2,700 2,700 2,700 2,700 2,700 2,700 2,700 2,700 2,700 2,700 Desalinated
Water
Carlsbad
Desalination
Plant
(purchased
under Take or
Pay with
SDCWA)
2,500 2,500 2,500 2,500 2,500 2,500 2,500 2,500 2,500 2,500 Subtotal Potable 14,915 14,915 16,174 16,174 16,263 16,263 16,368 16,368 16,487 16,487 Subtotal Non-Potable 3,898 10,539 4,218 10,539 4,218 10,539 4,218 10,539 4,218 10,539 Total 18,813 25,454 20,392 26,713 20,481 26,802 20,586 26,907 20,705 27,026 Notes: CMWD receives 2,500 AFY desalinated water through a purchase agreement with SDCWA. If the plant produces more desalinated water and SDCWA purchases more than the 48,000 AFY that it currently purchases, CMWD may receive an additional 5.21% of the additional amount available. Because of uncertainty regarding this water, it has been omitted from this table as an available volume. Purchases from SDCWA are not limited by Total Right or Safe Yield.

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6.10 Special Considerations
Special conditions that may affect CMWD’s water supply include climate change and regulatory impacts on the reliability of surface water supplies, particularly imported surface water supplies.

6.10.1 Climate Change Impacts
Climate change is a concern for CMWD and other agencies within the San Diego region.

A summary of climate change vulnerabilities, impacts, and actions to address these impacts is provided in Section 3 System Description . While the exact effects of climate change are unknown, average temperatures will increase, weather events will be more intense and more frequent, and precipitation patterns will change. As with other agencies in the region, CMWD relies heavily on water purchased from SDCWA and more than half of the SDCWA’s portfolio comes from imported supplies (SDCWA 2026). These imported supplies come from the SWP and the Colorado River. SWP reliability is dependent on rainfall and snowpack, and the timing of snowmelt. Climate change will make snowpack less reliable, either through changes in amount of water stored in snowpack, or through changes to the timing of snowmelt (e.g., earlier melt means excess water is available when demands are low, and less water is available during warmer months when demands are higher). Extreme weather events could damage imported water infrastructure or could exacerbate drought conditions. Extreme climate events, such as prolonged droughts, are also expected to increase fire event frequency and severity, further exacerbating water quality issues and flooding risk associated with fire-prone and flood-prone areas.

As identified by the Climate Change Vulnerability Assessment (see Section 3 System Description), drought was identified as a significant climate hazard for the city’s infrastructure and facilities, receiving a high vulnerability score. This high vulnerability score reflects substantial impacts that drought conditions can have on infrastructure and facilities. Local supply development is anticipated to help mitigate climate change impacts by developing drought-resilient supplies (e.g. recycled water), reduci ng potential supply disruptions from imported water, and reducing overall energy demands for providing water to customers.

6.10.2 Regulatory Conditions
One of the most significant regulatory drivers is the ongoing update of the Bay -Delta Water Quality Control Plan, which governs flow, salinity, and ecosystem protection measures for the Sacramento –San Joaquin Delta. The Bay -Delta watershed supplies a substantial portion of the SWP deliveries that ultimately support SDCWA and MWD supplies delivered to CMWD. Draft updates released in 2024–2025 propose new flow May 12, 2026
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objectives and implementation pathways that could alter SWP operations and influence the availability of imported supplies to Southern California. These include both a regulatory compliance pathway and an alternative voluntary -agreement pathway, each imposing different flow and habitat commitments that may affect future statewide conveyance reliability.

In addition to SWP supplies, Carlsbad receives imported water from the Colorado River via SDCWA and MWD. The regulatory landscape governing Colorado River supplies is undergoing significant transition as several foundational agreements, including the 2007 Interim Guidelines, the 2019 Drought Contingency Plans, and United States –Mexico agreements under the 1944 Water Treaty, are set to expire at the end of 2026 (Bureau of Reclamation 2026). In response, the Bureau of Reclamation has initiated the Post-2026 National Environmental Policy Act (NEPA) process, a multi-year effort that will define future operating rules for Lakes Mead and Powell and guide basin -wide water management for decades; a Draft Environmental Impact Statement was released in January 2026 for public review and comment. Meanwhile, negotiations among the seven basin states remain strained. Despite more than two years of discussions to restructure the century-old allocation framework, negotiators missed the November 2025 and the February 2026 mi lestones and now face a timeline of summer or fall 2026 to reach consensus before the federal government imposes its own plan, with recent reports indicating that states remain at an impasse over shortage -sharing and operational strategies. The prolonged uncertainty, exacerbated by federal indications that it may need to assume greater management authority if no agreement is reached, creates ongoing regulatory risk for agencies dependent on Colorado River supplies.

Additional statewide regulatory shifts, including evolving conservation reporting requirements, updated demand management expectations, and newly adopted potable reuse regulations, also have the potential to influence future local supply development and projected demands. These changes underscore the need for continued monitoring of state rulemaking and coordination with SDCWA and MWD to ensure supply planning reflects current and anticipated regulatory conditions.

6.10.3 Other Locally Applicable Criteria
The reliability of CMWD’s water supplies is closely tied to the regional wholesale dynamics between the SDCWA and MWD, the two agencies responsible for delivering imported Colorado River and SWP supplies to the region. Historically, SDCWA and MWD were engaged in a 15-year legal dispute over rates and the terms of conveying conserved Colorado River water, creating long-term uncertainty in wholesale pricing and cost allocation. However, in June 2025 the two agencies reached a landmark settlement that May 12, 2026
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ended all outstanding litigation, established a predictable fixed rate structure for water transfers beginning in 2026, and committed both agencies to improved collaboration and regional water supply efficiency (SDCWA 2025). The settlement replaces years o f conflict with a cooperative framework aimed at fiscal stability, enhanced reliability, and streamlined management of imported supplies. These benefits extend directly to retail agencies like CMWD, which depend on SDCWA for consistent and cost -stable wholesale water deliveries.

6.11 Energy Intensity
CMWD elected to estimate the energy intensity of its potable supplies using Appendix O of the Guidebook. A technical memorandum and the applicable DWR Appendix O tables have been included here as Appendix G of this 2025 UWMP.

Water energy intensity (EI) is the total amount of energy expended on a per AF basis to take water from the location CMWD acquires it to the point of delivery. Thus, EI includes conveyance, extraction, treatment, placing water into and taking it from storage, and distribution. CMWD’s water EI only accounts for the water management processes occurring within its operational control; energy use associated with the extraction, treatment and conveyance of wholesale water to CMWD’s points of diversion is not included. CMWD receives its potable water from SDCWA and this water is already treated prior to entering CMWD’s distribution system. CMWD also receives potable water from the Carlsbad Desalination Plant. The desalinated water is also already treated prior to entering CMWD’s operational control and the energy involved in delivering the desalinated water is captured in the overall distribution system energy demands. Thus, energy demands for CMWD’s potable system are limited to the requirements for distribution a nd limited local storage. As of 2026, CMWD’s potable water distribution system is entirely gravity fed.

Using San Diego Gas & Electric billing data for CMWD, which documents the amount of power needed to serve CMWD potable water equipment, such as chlorination equipment, pumping, and SCADA monitoring equipment, CMWD’s total energy use associated with potable water supplies for January -December 2025 was 308,318 kWh. During this same timeframe, CMWD received 14,462 AF of water, including desalinated seawater and purchased water from SDCWA that was placed in local storage or distributed to customers. Note that water placed in storage in any given year is excluded from gross water use reported elsewhere in this document. CMWD uses hydropower from the pressure difference of purchased SDCWA water and CMWD operational pressures. During the time period from January – December 2025 , CMWD generated 220,602 kWh of hydropower from this source. This represents seven months of e nergy generation as the May 12, 2026
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hydrogenator was down for repairs and maintenance during five months last year. This type of hydropower is referred to by DWR as “consequential” hydropower because it is generated as a consequence of water delivery. According to DWR recommended methods for estimating EI (Appendix O of the Guidebook), this “consequential” hydropower is subtracted from CMWD’s total energy use, to result in a net energy use of 87,716 kWh over the 2025 year. CMWD’s potable water system therefore had a local EI of 14.31 kWh/MG in 2025, as calculated according to the DWR UWMP Guidebook Appendix O methods. Repair and replacement of the hydrogenator will result in higher consequential hydropower in the future, which will lower CMWD’s potable water EI. The energy savings are applied to other utilities electric bills as credits.

Monthly energy demands vary greatly from month to month, depending on the length of time water remains in local storage, the level of demand (affecting pumping and storage levels), and the need to implement minor treatment or mixing to maintain potable quality.

In addition, CMWD has made investments in its potable water distribution system to rely primarily on gravity instead of pumps.

According to Appendix O of the Guidebook, “the energy intensity of recycled water operations is the incremental amount of energy consumed within an urban water supplier’s operational control to convey, treat, and distribute recycled water supplies that exceeds the amount of energy that otherwise would have been required to collect, treat, and discharge wastewater effluent divided by the amount of water entering the recycled water distribution system.” CMWD , through its contract with EWA operators, is responsible for operational control over the Carlsbad WRF. The amount of electricity used by the Carlsbad WRF for recycled water treatment during the period January -December 2025 was 1,400,207 kWh according to EWA invoice records . In addition, CMWD has operational control over recycled water distribution, which used 2,817,429 kWh over the time period January-December 2025. Energy consumption for recycled water distribution has been unusually high since December 2024 when the Meadowlark WRF was taken offline for m aintenance. In a typical year, CMWD gravity feeds recycled water from the Meadowlark WRF. However, more energy was needed in 2025 to power CMWD pumps in order to distribute recycled water to Mahr reservoir. The Meadowlark WRF is expected to become operational in August 2026, at which time energy consumption for recycled water distribution will resume typical, lower levels. During that time period, 5,356 AF of recycled water entered CMWD’s recycled water process and 3,708 AF of recycled water was delivered t o customers . CMWD does not have operation control over wastewater treatment which could be netted out of the energy consumed to treat and distribute recycled water supplies . CMWD’s recycled water EI was 1, 428 kWh/MG in 2025, as calculated according to the DWR UWMP Guidebook Appendix O methods.

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Chapter 7: Supply Reliability and Drought Risk Assessment 7-1

7. WATER SUPPLY RELIABILITY AND DROUGHT RISK ASSESSMENT CMWD’s potable water reliability is dependent on the availability of SDCWA’s supplies.

CMWD has improved its supply reliability by increasing recycled water use, using local desalinated seawater, and reducing water demands. These two sources of local supply are generally drought-resistant and highly reliable, while reducing imported demands lessens the impact statewide restrictions have on CMWD’s access to potable supplies. SDCWA has also taken action to expand its supply portfolio and decrease dependence on water imported via MWD; however, there remain several threats to supply reliability within CMWD’s service area.

7.1 Constraints on Water Resources
CMWD’s water supply reliability is affected by legal, environmental, water quality, or climatic factors. As noted throughout th e 2025 UWMP, CMWD’s potable demands are served with potable water purchased from SDCWA and is subject to availability of and access to those supplies. A lack of supply diversity contributes to potential supply constraints. Table 7-1 provides a summary of potential threats to supply reliability for CMWD’s various sources of potable and non-potable water.

TABLE 7-1: CONSTRAINTS ON WATER SUPPLIES
Source Potential Constraint on Supply
Imported
Water1
Legal: Current supply from SWP is occasionally inconsistent due to legal and environmental factors. Future supply may not be consistent due to delays in construction, legal rulings, or environmental decisions. Colorado River supplies are subject to legal decisions regarding the Quantification Settlement Agreement, which could reduce future supplies.

Climatic: Drought and climate change could result in reductions of imported water supply. This risk increases during extended drought, when both SWP and Colorado River supply may be reduced. Mandatory use restrictions imposed by the State during drought may affect ability to utilize supply, even if sufficient supplies are available locally.

Desalinated
Seawater
No constraints identified at this time unless unexpected infrastructure failure occurs.

Groundwater
Legal: CMWD has uncertain groundwater rights.

Water quality: The Mission Sub-Basin has high levels of total dissolved solids (TDS) and requires desalination for potable use.

Other: Groundwater basins in the region have limited storage capacity.

Recycled
Water
Cost: Cost of recycled water system expansion can make it challenging to complete connections.
1 Refer to SDCWA’s 2025 UWMP for additional details regarding constraints on their supplies May 12, 2026
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Chapter 7: Supply Reliability and Drought Risk Assessment 7-2 Throughout the 2025 UWMP planning cycle, CMWD and SDCWA coordinated on reliability and water use forecasts . CMWD provided SDCWA with information on population growth and planned developments within the CMWD service area. SDCWA’s 2025 UWMP water use forecast differs from CMWD’s in that it incorporates a complex collection of datasets into a statistical model . However, the 2025 UWMPs are similar in that they incorporate anticipated local development growth into the ir forecasts of water demand. In meetings bet ween SDCWA and CMWD during the 2025 UWMP planning cycle, SDCWA confirmed that the minor differences in forecasted water use are not an issue for long-range reliability planning in SDCWA’s service area.

7.1.1 SDCWA Supply Constraints and Reliability Actions
SDCWA’s supply portfolio consists primarily of imported water from various sources, supplemented by desalinated seawater and runoff captured in local reservoirs. As noted in Table 7-1, the principal constraints on SDCWA’s imported supplies stem from legal and climatic factors. SWP deliveries may be curtailed during drought periods or seasonally due to regulatory requirements to maintain environmental flows or comply with judicial rulings and other legal agreements. Additionally, SWP conveyance may be interrupted by infrastructure outages related to maintenance, construction, or unfores een events.

Colorado River imports are governed by the Quantification Settlement Agreement (QSA), which remains subject to potential modification through legal processes; however, these supplies are generally regarded as more reliable than SWP deliveries and are not expected to experience similar constraints. Colorado River water does exhibit higher total dissolved solids (TDS) concentrations compared to SWP water, influencing SDCWA’s blended raw water quality. This characteristic does not impact CMWD’s su pply reliability, as CMWD purchases treated water from SDCWA rather than raw water.

Drought may also reduce availability of imported water to SDCWA, thereby reducing supply reliability for CMWD. During the 2014 drought, SWP deliveries were subject to allocation reductions in 2014, 2015, and 2016. Under the Lower Colorado River Basin Drought Contingency Plan (Lower Basin DCP; USBR 2019), California contractors, including MWD and SDCWA, committed to shortage allocations or “DCP Contributions” starting when the elevation of Lake Mead , a major storage reservoir, dropped to 1,045 feet. According to SDCWA’s 2025 UWMP, as of April 2025, projections indicate that it is unlikely that Lake Mead will reach a level that requires contributions from California thorough 2026. Operating agreements are set to expire in 2026 and new agreements would be negotiated to govern storage and cutbacks beyond 2026.

Over the last decades, SDCWA has taken steps to diversify its water supply with alternative sources and increase water reliability for the region. Such efforts include canal lining and May 12, 2026
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Chapter 7: Supply Reliability and Drought Risk Assessment 7-3 the Carlsbad Desalination Plant. SDCWA’s canal lining project provides conserved water by preventing unplanned loss to incidental recharge. This conserved water is guaranteed for SDCWA under the terms of the project. SDCWA also enabled construction of the Carlsbad Desalination Plant by agreeing to a minimum annual purchase of desalinated water from the facility. This increases supply reliability because it is a drought-proof local supply. Desalinated seawater from the Carlsbad Desalination Plant meets appro ximately 8% of the region’s potable water demands. In 2021, SDCWA enhanced system reliability by completing major rehabilitation of the historic First Aqueduct and installing new fish-friendly intake pumps at the Carlsbad Desalination Plant, improving both resilience and operational performance (SDCWA 2021).

The reduced availability of any one of SDCWA’s supply sources would be buffered because of the diversity of the supplies; the region’s wholesale supplies are not reliant on a single source. To replace or supplement an existing supply, SDCWA could take steps to increase development of transfers or distribution of seawater desalination. SDCWA’s 2025 UWMP should be consulted for details regarding its actions to ensure consistency of the wholesale water supply. While regional efforts to improve supply diversification, storage, and system redundancy have worked to reduce the impacts such allocations have on local access to supplies, there is potential that mandatory use restrictions (at a statewide level) will be enacted during severe drought. Such restrictions, including those put in place by the State in 2015, may not affect supply that the region has in storage, but could affect the region’s ability to utilize supplies.

In addition, many of SDCWA’s member agencies are taking steps to diversi fy their water supplies through recycled water, groundwater, potable reuse and other local supply projects. These local and regional efforts to invest in major capital infrastructure projects and implement adaptive management initiatives have resulted in substantial long-term water use efficiency gains across the region. By improving water efficiency, the region is protecting the reliability of its various supplies.

7.1.2 CMWD Local Supply Constraints and Reliability Actions CMWD’s reliance on SDCWA for potable supplies creates vulnerability to potential supply disruptions within SDCWA’s system. As a result, CMWD expanded its local resources, which currently include recycled water and desalinated seawater, along with potential rights to a potential groundwater source.

Constraints on recycled water are capacity, connectivity, and the associated costs of providing additional connections. CMWD’s Phase III Recycled Water Project expanded its tertiary recycled water production capacity, storage, and distribution system to se rve additional customers. The Phase III Recycled Water Project was completed in 2025.

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Chapter 7: Supply Reliability and Drought Risk Assessment 7-4 Although there are currently no feasible new additional recycled water pipeline connections identified, it is possible that some additional customers could be converted to recycled water if they are located adjacent to the existing system. However, such demand for recycled water are expected to be low, and timing and ability to convert additional customers remains uncertain. As such, CMWD has conservatively assumed in this 2025 UWMP that recycled water demand will not increase beyond 2025. As part of the NS DWRC, CMWD is participating in a cooperative effort of nine north San Diego County water and wastewater agencies to maximize recycled water use and improve interconnectivity between their non-potable water systems. This effort would allow for additional flexibility in non-potable water system operation and increase recycled water efficiencies; however, cost estimates for infrastructure and water rates are considered prohibitive to the projects moving forward at this time. To help defray the cost of expanding its recycled water services, CMWD has actively pursued additional funding programs to help cover costs of the Phase III Recycled Water Project, including grants from the state’s Proposition 84 and Proposition 1, and U.S. Bureau of Reclamation’s Title XVI program, as well as a low-interest loan through the Clean Water State Revolving Fund.

While CMWD is currently receiving its desalinated seawater via SDCWA’s pipelines, it is not exploring constructing a direct connection to the desalinated seawater pipeline at this time. A direct connection between the Carlsbad 5 Flow Control Facility and P ressure Reducing Station and the Carlsbad Desalination Plant would provide a local, drought- proof supply that would function independently of SDCWA’s distribution system. This would create redundancy in the potable distribution system that would increase reliability of water deliveries from a drought-proof, secure, supply. As noted in Chapter 6, CMWD is not pursuing further development of this supply at this time.

To further diversify its local supplies, CMWD is continuing to monitor the costs and benefits of developing its groundwater rights (refer to Section 6 Water Supply).

Groundwater in the Mission Subbasin is high in TDS and would require desalination before use as a supply. The addition of groundwater to CMWD’s supply portfolio could reduce its reliance on SDCWA to meet potable demands. However, because CMWD is not currently working to reestablish groundwater rights and the potential available volume of groundwater supply is uncertain, it has been excluded from CMWD’s supply portfolio in this 2025 UWMP.

CMWD is also collaborating with member agencies of the NSDWRC on development of a potable reuse program known as the North County One Water Program. The City of Carlsbad is expected to receive purified water from this effort by 2035. However, because the North County One Water Program is still in the planning stages, it is not counted as a verifiable future water supply for the purposes of the 2025 UWMP.

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Chapter 7: Supply Reliability and Drought Risk Assessment 7-5 In the event of a severe drought, CMWD could effectively implement temporary water use reduction measures as defined in the water shortage contingency plan (see Chapter 8) to assist in ensuring reliability. Such use reduction measures were implemented in the 2014 to 2017 drought and were successful in helping CMWD reach its temporary state - mandated reduction target of 28% under the State’s Emergency Drought Restrictions issued in 2015.

7.2 Water Service Reliability Assessment
CMWD relies on its wholesaler’s diversified water supply portfolio designed to provide reliable potable water service under normal, single-dry, and multiple-dry year conditions.

CMWD’s wholesaler, SDCWA, primarily delivers imported drinking water sourced from the Colorado River via the Colorado River Aqueduct and from Northern California through the State Water Project, from both direct, SDCWA-controlled supplies and via MWD.

This section evaluates the ability of CMWD to meet projected customer demands under a range of normal, single-dry, and multiple-dry year hydrologic conditions, as required by the Urban Water Management Planning Act. The assessment examines the reliability of existing and planned water supplies, considers potential vulnerabilities, and identifies the strategies in place to ensure a consistent and sustainable water supply through the 20-year planning horizon.

7.2.1 Year Type Characterization
CMWD’s available water supply is evaluated under three scenarios: an average/ normal water year, a single -dry water year, and a five -year multiple -dry water year scenario.

Supplies from SDCWA during single - and multiple -dry years are based on historical drought conditions identified in Table 7-2 and defined in SDCWA’s 2025 UWMP. CMWD’s two quantified local supplies, desalinated seawater and recycled water, are considered drought-resilient and remain unaffected by dry conditions. While recycled water demand may increase during drought due to changes in irrigation practices, CMWD has sufficient production capacity to meet anticipated demand (see Table 6-6). Because potable demands beyond those that can be met by local supply are met through purchases from SDCWA, CMWD’s water supply reliability analysis is aligned with SDCWA’s reliability assessment.

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Chapter 7: Supply Reliability and Drought Risk Assessment 7-6 TABLE 7-2: B ASIS OF WATER YEAR DATA (WATER SERVICE RELIABILITY

ASSESSMENT)
DWR Table 7-1 Retail: Basis of Water Year Data (Reliability Assessment) Base Year Volume Available (AFY)
Available Supplies if Year Type Repeats
% of Average Supply
1991-2020 20,195 100%
2013, 2018, 2021 21,461 106%
2011 21,530 107%
2012 21,737 108%
2013 21,943 109%
2014 22,152 110%
2015 22,365 111%
Notes: CMWD selected base years that aligned with SDCWA’s 2025 UWMP supply reliability assessment. SDCWA supplies are expected to be reliable through all years of a multiple year drought, with additional carryover supplies available in extended dry periods. As presented here, “% of Average Supply” indicates percent supply available to meet both potable and non-potable demands due to diversification and/or carryover storage.

Although Table 7-2 identifies the percentage of available supply to meet demand, supply availability will vary by source because CMWD’s local supplies would not be affected by dry year conditions. Changes to supply availability cannot be applied equally across each source. Potable and recycled water demands are both considered in CMWD’s supply reliability assessment because recycled water use offsets potable demands, while shortages in recycled water supplies require supplementation with potable supplies.

7.2.1.1 Water Service Reliability – Normal Year
SDCWA’s 2025 UWMP projected overall demands would increase over time and across scenarios, with some variability depending on the time frame and hydrologic scenario.

CMWD anticipates that its demands would generally increase in dry year scenarios consistent with SDCWA’s overall demand increases in corresponding scenarios. Due to uncertainty inherent to projecting demands during dry hydrologic conditions, CMWD’s demand projections increase over dry year scenarios at a consistent rate across time frames (2030, 2035, 2040, 2045, and 2050), calculated as the average increase presented in SDCWA’s 2025 UWMP. Table 7-3 identifies how CWMD’s demands are projected to change, as a percent of normal, for different scenarios. Table 7-4 demonstrates that, under normal year conditions, available supplies are sufficient to meet projected demands.

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Chapter 7: Supply Reliability and Drought Risk Assessment 7-7 While demands are projected to increase, SDCWA retains the right to purchase additional water from MWD in years where local supplies are insufficient to meet demands. Under SDCWA’s purchase agreement with MWD, SDCWA holds preferential rights that ensure access to water necessary to meet unmet demands across all planning scenarios.

Additionally, SDCWA maintains substantial carryover storage that can be utilized during extended dry periods. SDCWA’s water service reliability analysis (SDCWA 2026) finds that there would be a supply surplus in all planning scenarios. Thus, CMWD expects to secure adequate potable supplies from SDCWA to supplement desalinated seawater, as SDCWA’s projections account for increased Member Agency demands under dry -year conditions. These projections also incorporate anticipated changes in Member A gency local supplies, ensuring a comprehensive assessment of regional demand on SDCWA resources.

TABLE 7-3: S UPPLY AND DEMAND ASSUMPTIONS, AS PERCENT OF NORMAL Source
Normal
Water
Year
Single-Dry
Water Year
Multiple-Dry Water Years
Year 1 Year 2 Year 3 Year 4 Year 5
Demands
Potable Water 100% 106% 107% 108% 109% 110% 111%
Recycled
Water 100% 106% 107% 108% 109% 110% 111%
Total Percent of Normal
Demands 106% 107% 108% 109% 110% 111%
Supplies
SDCWA
Purchases 100% 107% 108% 109% 110% 111% 113%
Seawater
Desalination 100% 100% 100% 100% 100% 100% 100%
Recycled
Water 100% 106% 107% 108% 109% 110% 111%
Total Percent of Normal
Potable Supplies 106% 107% 108% 109% 110% 111%
Total Percent of Overall
Normal Supplies 106% 107% 108% 109% 110% 111%
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Chapter 7: Supply Reliability and Drought Risk Assessment 7-8 TABLE 7-4: NORMAL WATER YEAR SUPPLY AND USE COMPARISON
DWR Table 7-2 Retail: Normal Year Supply and Use Comparison Source 2030 2035 2040 2045 2050
Demands
Potable Demand 14,915 16,174 16,263 16,368 16,487
Non-Potable Demand 3,898 4,218 4,218 4,218 4,218
Total Normal Year
Demand 18,813 20,392 20,481 20,586 20,705
Supplies
SDCWA Purchases 12,415 13,674 13,763 13,868 13,987
Seawater Desalination 2,500 2,500 2,500 2,500 2,500
Normal Year Potable
Supply 14,915 16,174 16,263 16,368 16,487
Recycled Water 3,898 4,218 4,218 4,218 4,218
Total Normal Year
Supply 18,812 20,393 20,482 20,586 20,706
Surplus/(shortfall) 0 0 0 0 0

7.2.1.2 Water Service Reliability – Single Dry Year
The single-dry year scenario is based on an average of 2013, 2018, and 2021 single dry - year supplies. SDCWA anticipates that regional demands will increase by approximately 6% in a single dry-year, and CMWD assumes this increase remains consistent throughout the planning horizon. SDCWA’s analysis, which included a conservative consideration of member agency local supplies, concludes that sufficient supplies are available to meet projected demands even under single -dry year conditions. In fact, SDCWA’s analy sis (SDCWA 2026) anticipates a supply surplus. Increased member agency demand would be met with increased purchases from MWD, which SDCWA has adequate access to meet the increased demands. As a result, even if CMWD demands for SDCWA supplies were to be higher than forecasted by SDCWA, because SDCWA expects a supply surplus, CMWD assumes that SDCWA will fully meet any potable water needs not supplied by local sources, as reflected in Table 7-5 and Table 7-6.

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Chapter 7: Supply Reliability and Drought Risk Assessment 7-9 TABLE 7-5: S INGLE DRY YEAR SUPPLY AND DEMAND COMPARISON DWR Table 7-3 Retail: Single Dry Year Supply and Use Comparison Source 2030 2035 2040 2045 2050
Demands
Potable Demand 15,850 17,187 17,282 17,394 17,520
Non-Potable Demand 4,142 4,482 4,482 4,482 4,482
Total Normal Year Demand 19,992 21,670 21,764 21,876 22,002 Supplies
SDCWA Purchases 13,350 14,687 14,782 14,894 15,020
Seawater Desalination 2,500 2,500 2,500 2,500 2,500
Single Dry Year Potable Supply 15,850 17,187 17,282 17,394 17,520 Recycled Water 4,142 4,482 4,482 4,482 4,482
Total Single Dry Year Supply 19,992 21,670 21,764 21,876 22,002 Surplus/(shortfall) 0 0 0 0 0

7.2.1.3 Water Service Reliability – Five Consecutive Dry Years Under a five-consecutive-year drought scenario, the region would experience sustained dry hydrologic conditions. Water demands for the multi-dry year scenario were calculated based on a 1% annual increase in water use from the single dry -year demand forecast, consistent with the SDCWA analysis.

SDCWA’s analysis (SDCWA 2026) concludes that sufficient local and imported supplies exist to meet member agency demands throughout the 2025–2050 planning horizon. In fact, SDCWA’s water service reliability analysis finds that there would be a supply surplus in all planning scenarios. This approach accounts for the demand management actions anticipated from SDCWA and its member agencies during drought conditions, which are expected to limit demand increases relative to what typically occurs under hot and dry weather. Consistent with SDCWA’s findings, CMWD assumes that any demand exceeding local supply capacity will be met through additional purchases from SDCWA, and that SDCWA has sufficient supplies to meet this increased demand. The SDCWA anticipates a surplus of water supplies in all five years of a drought and would have enough supply to meet CMWD’s increased demands, even if CMWD demands are greater than expected.

As shown in Table 7-5 and Table 7-6, CMWD’s projected supplies for single - and multiple-dry year scenarios are adequate to meet demand without requiring extreme conservation measures. While the analysis below shows supply would equal demand, CMWD has access to greater supply if demand exceed expectations because the SDCWA has additional supplies available beyond those currently provided to CMWD.

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Chapter 7: Supply Reliability and Drought Risk Assessment 7-10 TABLE 7-6: M ULTIPLE DRY YEARS SUPPLY AND DEMAND COMPARISON DWR Table 7-4 Retail: Multiple Dry Years Supply and Use Comparison Source 2030 2035 2040 2045 2050
Multiple-
Dry Year
(First
Year)
Potable Water Demands 15,901 17,243 17,338 17,450 17,577 Non-Potable Demands 4,156 4,497 4,497 4,497 4,497 Total Multiple-Dry Year 1
Demand 20,057 21,740 21,835 21,947 22,074 SDCWA Purchases 13,401 14,743 14,838 14,950 15,077 Seawater Desalination 2,500 2,500 2,500 2,500 2,500 Multiple-Dry Year 1 Potable
Supplies 15,901 17,243 17,338 17,450 17,577 Recycled Water 4,156 4,497 4,497 4,497 4,497 Total Multiple-Dry Year 1
Supply

20,057 21,740 21,835 21,947 22,074 Multiple-
Dry Year
(Second
Year)
Potable Water Demands 16,054 17,409 17,505 17,618 17,746 Non-Potable Demands 4,196 4,540 4,540 4,540 4,540 Total Multiple-Dry Year 2
Demand 20,249 21,949 22,045 22,158 22,286
SDCWA Purchases 13,554 14,909 15,005 15,118 15,246 Seawater Desalination 2,500 2,500 2,500 2,500 2,500
Multiple-Dry Year 2 Potable
Supplies 16,054 17,409 17,505 17,618 17,746 Recycled Water 4,196 4,540 4,540 4,540 4,540 Total Multiple-Dry Year 2
Supply 20,249 21,949 22,045 22,158 22,286
Multiple-
Dry Year
(Third
Year)
Potable Water Demands 16,206 17,574 17,671 17,785 17,914 Non-Potable Demands 4,235 4,583 4,583 4,583 4,583 Total Multiple-Dry Year 3
Demand 20,441 22,157 22,254 22,368 22,497 SDCWA Purchases 13,706 15,074 15,171 15,285 15,414 Seawater Desalination 2,500 2,500 2,500 2,500 2,500
Multiple-Dry Year 3 Potable
Supplies 16,206 17,574 17,671 17,785 17,914 Recycled Water 4,235 4,583 4,583 4,583 4,583 Total Multiple-Dry Year 3
Supply 20,441 22,157 22,254 22,368 22,497
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Chapter 7: Supply Reliability and Drought Risk Assessment 7-11 DWR Table 7-4 Retail: Multiple Dry Years Supply and Use Comparison Source 2030 2035 2040 2045 2050
Multiple-
Dry Year
(Fourth
Year)
Potable Water Demands 16,360 17,741 17,839 17,954 18,085 Non-Potable Demands 4,276 4,627 4,627 4,627 4,627 Total Multiple-Dry Year 4
Demand 20,636 22,368 22,466 22,581 22,711
SDCWA Purchases 13,860 15,241 15,339 15,454 15,585 Seawater Desalination 2,500 2,500 2,500 2,500 2,500
Multiple-Dry Year 4 Potable
Supplies 16,360 17,741 17,839 17,954 18,085 Recycled Water 4,276 4,627 4,627 4,627 4,627 Total Multiple-Dry Year 4
Supply 20,636 22,368 22,466 22,581 22,711 Multiple-
Dry Year
(Fifth
Year)
Potable Water Demands 16,517 17,912 18,010 18,126 18,258 Non-Potable Demands 4,317 4,671 4,671 4,671 4,671 Total Multiple-Dry Year 5
Demand 20,834 22,583 22,681 22,798 22,929 SDCWA Purchases 14,017 15,412 15,510 15,626 15,758 Seawater Desalination 2,500 2,500 2,500 2,500 2,500
Multiple-Dry Year 5 Potable
Supplies 16,517 17,912 18,010 18,126 18,258 Recycled Water 4,317 4,671 4,671 4,671 4,671 Total Multiple-Dry Year 5
Supply 20,834 22,583 22,681 22,798 22,929

7.2.2 Management Tools and Options
CMWD employs a combination of local supply development, Demand Management Measures (DMMs), and regional coordination to maximize the use of local water resources and reduce reliance on imported water supplies. CMWD’s local supply portfolio includes recycled water and seawater desalination through regional partnerships. These local supplies supplement purchased water from SDCWA and improve overall supply reliability, particularly during drought conditions.

CMWD implements comprehensive DMMs that reduce potable water demand and enhance the effectiveness of local supplies. These measures include enforceable water waste prevention ordinances, full metering of all water connections, conservation-oriented rate structures, advanced metering infrastructure with real -time leak detection, and proactive management of distribution system water losses. Ordinance May 12, 2026
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Chapter 7: Supply Reliability and Drought Risk Assessment 7-12 No. 48, now codified into CMWD Water Code under Title 3, establishes a six-level Water Shortage Contingency framework that enables CMWD to implement progressively stringent mandatory demand reductions in response to regional supply conditions.

Public education, outreach, and incentive programs further support long -term demand reductions. CMWD collaborates with regional partners to provide rebates, water audits, landscape education, school programs, and conservation outreach that promote efficient indoor and outdoor water use. These programs result in permanent reductions in potable water demand, allowing local water supplies to meet a greater share of system needs.

Recycled water is another key component of CMWD’s local supply strategy, with non-potable demands such as landscape irrigation increasingly served by recycled water rather than potable supplies. Ongoing coordination with regional agencies supports continued expansion of recycled water use where feasible.

7.3 Drought Risk Assessment
As part of this 2025 UWMP, a Drought Risk Assessment (DRA) was conducted to evaluate the reliability of each supply source under extended drought conditions. The findings of the DRA inform the development of demand management strategies and future water supply projects, while also serving as a tool to assess the effectiveness of CMWD’s Water Shortage Contingency Plan (WSCP). This evaluation helps identify potential vulnerabilities and supports proactive planning to mitigate risks before the onset of a prolo nged drought. The DRA may be updated periodically to incorporate new data or address unforeseen circumstances, ensuring continued relevance and adaptability.

7.3.1 Data and Methodology
Per UWMP requirements, the DRA is based on the five driest consecutive years on record.

To align with SDCWA’s DRA, the historical period used in this analysis is the period from 2014 to 2018. This represents the five -year period SDCWA determined had the lo west local water supply production from surface water and groundwater, the two local water supplies most susceptible to weather -induced variation. Per SDCWA’s methodology, projected local surface water and groundwater supplies reflect actual production fro m 2014 to 2018. Other local supplies are assumed not to experience a reduction in availability over the five -year dry period because of the drought -resilience of these supplies. CMWD’s existing local supplies, desalinated seawater and non-potable recycled water, are held constant at current 2025 production volumes for the purposes of the DRA.

Projected demands were calculated by escalating 2025 demands annually for five years based on multipliers provided by SDCWA (shown in Table 7-6). The multipliers are based May 12, 2026
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Chapter 7: Supply Reliability and Drought Risk Assessment 7-13 on a weather index developed to assess the impact of dry/hot weather on demands (SDCWA 2025).

7.3.2 Determination of Reliability
SDCWA anticipates a surplus of water supplies in all five years of a drought and would have enough supply to meet CMWD’s increased demands. Based on the analysis shown in Table 7-7, CMWD would be able to meet its water demands in all five years, before accounting for the impacts of any actions under the WSCP.

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Chapter 7: Supply Reliability and Drought Risk Assessment 7-14 TABLE 7-7: FIVE -YEAR DROUGHT RISK ASSESSMENT TABLES
DWR Table 7-5: Five-Year Drought Risk Assessment
Water Code Section 10635(b)(3)
CMWD Drought Risk Assessment 2026 2027 2028 2029 2030
Local Supplies1
Seawater Desalination 2,500 2,500 2,500 2,500 2,500 Non-Potable Recycled Water 3,708 3,708 3,708 3,708 3,708 Total Projected Local Supplies 6,208 6,208 6,208 6,208 6,208 Demand
CY 2025 Demand1 18,170 18,170 18,170 18,170 18,170
Demand Projection Multiplier2 109% 109% 111% 114% 116%
Consecutive 5-Year Drought
Demand 19,805 19,805 20,169 20,714 21,077
SDCWA Purchases3 13,597 13,597 13,597 13,597 13,597
Total Projected Supplies with
SDCWA Purchases 19,805 19,805 20,169 20,714 21,077
Impacts of WSCP Actions 0 0 0 0 0
Remaining Potential Surplus
Supply, or (Shortage) that will be
addressed through Management
Actions
0 0 0 0 0

1. All supplies held constant at actual CY 2025 levels to align with SDCWA 2025 UWMP methodology.

2. Based on a weather index developed to assess the impact of dry/hot weather on water demands, used in SDCWA's 2025 UWMP.

3. SDCWA anticipates having a surplus of supply per its 2025 UWMP.

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Chapter 8: Water Shortage Contingency Plan 8-1

8. WATER SHORTAGE CONTINGENCY PLAN
CMWD’s arid climate, limited local supplies, and growing population make water shortage planning an important component of supply management, especially in light of the region’s history with severe drought and the potential for increased frequency, intensity, and duration of droughts due to climate change. CMWD has adopted measures and plans to address water shortages, should supplies be more limited than demand. This section describes CMWD’s W ater Shortage Contingency Plan (WSCP), considers the potential impacts shortages could have on revenue and expenses, and summarizes CMWD’s planned response in the event of catastrophic supply loss.

8.1 Water Supply Reliability Analysis
In July 2024, CMWD codified all of its water Ordinances into the Carlsbad Municipal Water District Code (CMWD Water Code) as part of a District and City effort to organize and provide consistency in municipal and water code requirements and references (Cit y of Carlsbad 2024). Title 3 of the CMWD Water Code now includes the requirements from the two primary ordinances in place to prohibit water waste and encourage water use efficiency within its service area (Ordinance No. 44 – Drought Response Plan and Wate r Conservation Program and Ordinance No. 46 – Watering Schedules), which were both adopted in 2009. On June 7, 2022, CMWD adopted Ordinance No. 48, which amended Ordinance No. 44 and No. 46 to better align its regulatory framework with changes at the regional and state level around drought and conservation. The CMWD Water Code (City of Carlsbad N.d.) is updated as needed to comply with State regulations and regional response to drought conditions.

CMWD Water Code Title 3, Chapter 3.12 (previously Ordinance No. 48) mirrors SDCWA’s 2020 Model Drought Ordinance and establishes a six-level Water Shortage Contingency framework, consistent with WSCP guidance from DWR ( Table 8-2). CMWD Water Code Title 3, Chapter 3.12 provides CMWD with the authority to declare water shortage levels based on regional supply conditions and to implement progressively stringent water conservation measures as shortages intensify. CMWD Water Code Title 3, Chapter 3.12 includes both permanent water -waste prohibitions and mandatory demand reduction actions tied to each shortage level, ensuring a structured and enforceable response to drought conditions. The ordinance modernizes and expands CMWD’s previou s drought provisions by incorporating updated statewide requirements, improving consistency with the WSCP, and ensuring that CMWD can respond effectively to shortages of varying severity. A complete copy of the CMWD Water Code is included in Appendix H and the contents of each are described in further detail below.

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Chapter 8: Water Shortage Contingency Plan 8-2
Because CMWD is dependent upon SDCWA for its water supply, SDCWA’s 2025 UWMP should also be consulted for its water shortage contingency plan. Emergency response stage actions become effective when SDCWA declares that it is unable to provide sufficient water supplies to meet the ordinary demands and requirements of its member agencies to the extent that insufficient water would be available. When SDCWA announces its stage declaration, CMWD concurrently declares its corresponding stage.

8.1.1 Legal Authorities
Under California law, including CWC Chapters 3.3 and 3.5 of Division 1, Parts 2.55 and 2.6 of Division 6, Division 13, and Article X, Section 2 of the California Constitution, the CMWD Board of Directors is authorized to implement the water shortage actions outlined in this Water Shortage Contingency Plan (WSCP). In all water shortage cases, shortage response actions to be implemented will be at the discretion
of the Board of Directors and will be based
on an assessment of the supply shortage, customer response, and need for demand reductions.

It is noted that upon proclamation by the Governor of a state of emergency under the California Emergency Services Act (Chapter 7 [commencing with Section 8550] of Division 1 of Title 2 of the Government Code) based on drought conditions, the State will defer to implementation of locally -adopted water shortage contingency plans to the extent practicable. CMWD will coordinate with regional and local water suppliers for which it provides water supply services for possible proclamation of a local emergency as necessary.

8.1.2 Plan Adoption, Submittal and Availability
CMWD’s WSCP is a part of CMWD’s 2025 UWMP, however, the WSCP also functions as a stand-alone document that can be amended, as needed, without amending the City’s 2025 UWMP. Additional requirements of the WSCP, such as the annual supply and demand reliability assessment protocol, are described below. The process for approving WSCP amendments and conducting required public hearings are described in Section 10 Plan Adoption, Submittal, and Implementation.

8.2 Annual Water Supply and Demand Assessment Procedures This section describes the procedures used to conduct and approve the Annual Assessment. While the UWMP’s Drought Risk Assessment (DRA) assesses longer -term, multi-year water supply reliability, the Annual Assessment focuses on actual forecasted near-term water supply conditions (i.e., next 12 months). The prescribed steps and annual timing to complete the Annual Assessment and submit the final report are listed below to ensure consistency year-after-year regardless of CMWD staff changes:

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Chapter 8: Water Shortage Contingency Plan 8-3

1. March - April
a. CMWD determines CMWD local supply available.
b. CMWD coordinates with SDCWA to gather necessary information to conduct SDCWA Annual Assessment.

2. May
a. SDCWA announces member agency allocation determination for current year.
b. SDCWA determines carryover (and emergency storage apportionments if under emergency).
c. CMWD conducts Annual Assessment:
i. CMWD determines total supply available – inclusive of imported water supply.
ii. CMWD determines infrastructure constraints (including water quality conditions limiting local sources).
iii. CMWD determines expected estimated demand for current year and one subsequent dry year.
iv. CMWD compares supply and demand and makes a determination of the water supply reliability.

3. June
a. CMWD General Manager reviews and approves Annual Assessment determination.
b. CMWD coordinates with SDCWA on submittal of the report. Annual Assessment report to be submitted to the state by July 1.

8.2.1 Decision-Making Process
The Annual Assessment will document any anticipated shortage, any triggered shortage response actions, associated compliance and enforcement actions, and communication actions, should the following year be a dry year . These results and recommendations of the Annual Assessment will be provided to the General Manager for approval. In the event of anticipated foreseen water shortage level, if any, which would trigger recommendations for specific shortage response actions, this would be presented to the Board of Directors.

However, the Board of Directors has the discretion to declare water shortage levels at any time during the year that is appropriate, outside of the Annual Assessment process.

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8.2.2 Water Supply Projection: Data Inputs and Methodology For the Annual Assessment, CMWD evaluate s the reliability of the water system for the coming year, assuming it will be a dry year. Under normal (non -shortage) conditions, CMWD can purchase as much water as necessary from SDCWA to meet demands. When that supply (imported supply) is under shortage conditions, the amount of shortage (allocation of shortage) specific to CMWD is determined in a process led by SDCWA.

Evaluation of CMWD supply begins with SDCWA’s own supply evaluation as CMWD receives a large portion of its water supply from the SDCWA regional supply system.

SDCWA uses the availability of CMWD’s local supplies to determine CMWD’s imported water allocation. As such, in years in which imported supply is short, CMWD’s imported supply is dependent on availability of local supplies. To inform SDCWA’s allocation process, CMWD must describe and quantify in AF, each sourc e of CMWD-owned water supply. CMWD’s local water supply portfolio consists of desalinated seawater and recycled water. In the event of a regional shortage, imported water supplies include SDCWA imported water and SDCWA carryover storage.

The available water supply evaluation consider s hydrological and regulatory conditions.

The methodology for determining the available supply from each water supply source is presented in Table 8-1.

TABLE 8-1: SUPPLY SOURCE AVAILABILITY EVALUATION METHODOLOGY Supply Source Evaluation Methodology
Desalinated Seawater Assume 2,500 AFY and apply potential production constraints Recycled Water (Non-Potable) Determine previous year’s production and account for potential decreases in wastewater flow
SDCWA Imported Water
Allocation determined by SDCWA , based on SDCWA’s UWMP
reliability analysis for supply availability during dry years or as provided by SDCWA
SDCWA Carryover Storage Determine available supply to CMWD based on SDCWA WSCP and the most recent information

8.2.3 Planned Water Use for Current Year and Subsequent Dry Year: Data Inputs and Methodology
Unless otherwise specified, the Annual Assessment use s CMWD’s most recent unconstrained demand forecast to determine its current year water use. Unconstrained demand is defined as CMWD’s expected customer water need for the coming year prior to the application of shortage response actions. This is determined based on actual water use for the current year and consideration of required conservation (if any) across the year May 12, 2026
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that could have reduced water use below CMWD’s unconstrained demand, along with projected water use as identified in this UWMP. Additional real-time adjustments would be applied to account for factors such as weather, prior-year conditions, anticipated new demands for the year, and other factors pertinent to the land use and customer use patterns. Dry year demand is based on the single -dry year as defined in Section 7 Water Supply Reliability Assessment of CMWD’s 2025 UWMP, or in the event that the region is experiencing drought, the appropriate year of the multiple dry year scenario. Each year’s assessment will be informed by the characterizations in Section 6 Water Supply and other current pertinent factors and considerations.

8.2.4 Infrastructure Considerations: Data Inputs and Methodology CMWD is required to describe the methodology for identifying existing water supply infrastructure capabilities and potential constraints. CMWD’s existing water supply infrastructure is well-documented in its GIS system and continuously assessed by Water System Operations staff. Existing water supply infrastructure includes CMWD -owned infrastructure and imported and purchased water infrastructure. CMWD -owned infrastructure includes water treatment plants, pipelines, and pump stations. Imported and purchased water infrastructure includes a seawater desalination plant, and SDCWA’s aqueducts and regional pipelines. CMWD will evaluate existing water supply and capacities, as well as any constraints for the current year and for one subsequent dry year.

CMWD-owned infrastructure constraints may consider service area-level supply capabilities in the current year, such as shut -downs due to maintenance, construction impacts, and water quality impacts. In addition, CMWD should also consider new projects that may add cap acity. Once constraints have been identified, CMWD will determine whether the total quantified water supply (as determined according to Section 8.2.2 above) should be adjusted to account for these identified constraints. CMWD will coordinate with SDCWA to evaluate regional infrastructure constraints to determine how they would impact available CMWD water supplies, as applicable.

8.2.5 Evaluation Criteria: Data Inputs and Methodology
CMWD relies primarily on SDCWA to evaluate regional supply and demand and potential water shortage levels. CMWD’s supply and demand evaluation criteria are applied as minor adjustments to account for latest information on CMWD -owned supplies or unpredicted changes in CMWD demand. As such, CMWD will evaluate CMWD -owned supply storage levels, changes in recycled water availability, and recent water demand trends.

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8.3 Six Standard Water Shortage Stages and Shortage Response Actions The Drought Ordinance outlines CMWD’s six drought response stages, as shown in Table 8-2. These stages, and their prohibitions, are described below. Each level builds on the previous level(s), placing additional restrictions on water use. S hortage levels are consistent with regional and statewide levels and convey the relative severity of water supply shortage conditions.

TABLE 8-2: W ATER SHORTAGE CONTINGENCY PLAN LEVELS
DWR Table 8-1 Retail: Water Shortage Contingency Plan Levels Standard
Shortage
Level
Percent
Shortage
Range1
Water Shortage Condition
1 Up to 10% Drought Watch Condition - Reasonable probability that supplies will not meet demands
2 Up to 20% Drought Alert Condition - Supplies will not be able to meet expected demands
3 Up to 30% Drought Critical Condition - Supplies not meeting current demands 4 Up to 40% Drought Critical Condition - Supplies not meeting current demands 5 Up to 50% Drought Emergency Condition - Major failure of a supply, shortage, or distribution system
6 >50% Drought Emergency Condition - Major failure of a supply, shortage, or distribution system
1 One stage in the Water Shortage Contingency Plan must address a water shortage of 50%.

Notes: A water shortage above 50% triggers Level 6 restrictions, which include prohibition on outdoor water uses, and provides CMWD the authority to make further restrictions, as necessary, for non-compliant users, as well as for any CMWD customer should water supplies require.

Drought Response Level 1 – Drought Watch
A Level 1 Drought Watch condition may apply when SDCWA notifies its member agencies that a demand reduction of up to 10% is required to allow for adequate supplies to meet demands. CMWD’s Executive Manager shall declare the existence of Level 1 conditions, and Level 1 conservation practices shall be implemented.

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Drought Response Level 2 – Drought Alert
A Level 2 Drought Alert condition may apply when SDCWA notifies its member agencies that a demand reduction of up to 20% is required due to drought conditions or other reduction in supplies. The CMWD Board of Directors sha ll declare a Level 2 condition, at which point all water conservation measures under Level 1 must be adhered to, with the addition of Level 2 water use restrictions.

Drought Response Level 3 – Drought Critical
A Level 3 Drought Critical condition may apply when SDCWA notifies its member agencies that demand reductions of up to 40% are required due to drought or other reduction in supplies in order to have sufficient supplies for anticipated demands. The CMWD Board of Directors shall declare a Level 3 condition, requiring the continuation of conservation measures under Level 1 and Level 2, and the implementation of Level 3 water use restrictions.

Drought Response Level 4 – Drought Critical
A Level 4 Drought Critical condition may apply when SDCWA declares a water shortage emergency and notifies its member agencies that demand reductions of more than 40% are required in order to maintain sufficient supplies for anticipated demands. The CMWD Board of Directors shall de clare a Level 4 Drought Emergency in the manner and on the grounds provided in the California Water Code §350. With the declaration of a Level 4 drought response, all water conservation measures under Levels 1, 2, and 3 must be adhered to, with the addition of Level 4 mandatory conservation measures.

Drought Response Level 5 – Drought Emergency
A Level 5 Drought Emergency condition may apply when SDCWA declares a water shortage emergency and notifies its member agencies that demand reductions of approximately 50% are required to maintain sufficient water supplies for anticipated demands. The CMWD Board of Directors shall declare a Level 5 Drought Emergency in the manner and on the grounds provided in California Water Code §350. Upon declaration of a Level 5 drought response, all water conservation measures required under Levels 1, 2, 3, and 4 shall remain in effect, along with additional mandatory conservation measures necessary to achieve the required demand reductions.

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Drought Response Level 6 – Drought Emergency
A Level 6 Drought Emergency condition may apply when SDCWA declares a severe or emergency water shortage and determines that demand reductions greater than 50% are required due to critical supply constraints. The CMWD Board of Directors shall declare a Level 6 Drought Emergency in accordance with California Water Code §350. With the declaration of a Level 6 drought response, all water conservation measures from Levels 1 through 5 shall continue, together with the most stringent mandatory conservation actions to protect public health and safety and preserve essential water supplies.

In addition to implementing mandatory water use restrictions and prohibitions during shortage conditions, CMWD employs a range of supply and demand strategies to ensure adequate water is available to meet essential needs. At higher shortage levels, CMWD may activate supplemental supply options to help close any remaining gap between projected demands and available resources. These actions, such as drawing on stored emergency supplies or securing transfers from regional partners, provide important operational flexibility during more severe stages of a shortage. The specific supply -side measures CMWD may utilize are summarized in Table 8-3.

On the demand side, CMWD applies a tiered set of conservation and efficiency actions designed to progressively reduce water use as shortage levels increase. These measures range from ongoing water -waste prohibitions and public outreach efforts to more restrictive limits on irrigation, leak repair requirements, commercial best practices, and broad prohibitions on most outdoor potable water use at the highest shortage levels. The full suite of demand reduction measures is presented in Table 8-4.

TABLE 8-3: S UPPLY AUGMENTATION AND OTHER ACTIONS
DWR Table 8-2: Supply Augmentation and Other Actions
Shortage Level
Supply Augmentation
Methods and Other Actions
by Water Supplier
Shortage Gap
Reduction
Value
Additional Explanation or
Reference
5 Stored Emergency Supply 9% Maerkle Reservoir holds a
maximum 600AF.
6 Transfers 10%
City of Oceanside, Vallecitos
Water District, and SDCWA
would be a potential source.

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TABLE 8-4: DEMAND REDUCTION ACTIONS
DWR Table 8-3: Demand Reduction Actions
Shortage
Level
Demand Reduction Actions Shortage Gap
Reduction Value Additional Explanation or Reference Penalty, Charge, or Enforcement?
0 Other - Prohibit use of potable water
for washing hard surfaces 0.8% No washing down paved surfaces. No 0 Landscape - Restrict or prohibit runoff
from landscape irrigation 0.1% No runoff/overspray. No
0 Water Features - Restrict water use for
decorative water features, such as
fountains

1.4%
Recirculating fountains only.

No
0 CII - Restaurants may only serve water
upon request 0.2% Restaurant water upon request. No
0 CII - Lodging establishment must
offer opt out of linen service 0.2% Hotel laundry upon request. No 0 Other - Prohibit use of potable water
for construction and dust control 0.0% Non-potable water for construction purposes when available. No
1 Landscape - Limit landscape irrigation
to specific times 6.9% Irrigate residential and commercial landscape before 10 a.m. and after 6 p.m. No
1 CII - Other CII restriction or
prohibition 0.2% Irrigate nursery and commercial grower's products before 10 a.m. and after 6 p.m. No
1 Other - Customers must repair leaks,
breaks, and malfunctions in a timely
manner

0.8%
Repair leaks within 5 days of notification.

No
1 Expand Public Information Campaign

4.6%
CMWD increased public education and
outreach efforts to emphasize increased public
awareness of the need to implement water
conservation practices.

No
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DWR Table 8-3: Demand Reduction Actions
Shortage
Level
Demand Reduction Actions Shortage Gap
Reduction Value Additional Explanation or Reference Penalty, Charge, or Enforcement?
1 Provide Rebates for Landscape
Irrigation Efficiency 4.3% Ongoing programs. No
2 Landscape - Limit landscape irrigation
to specific days 6.9% Water limited to days assigned by CMWD (3 days/week). Yes
2 Landscape - Other landscape
restriction or prohibition 3.1% Limit lawn watering and landscape irrigation to 10 minutes unless using water efficient device. Yes
2 Landscape - Other landscape
restriction or prohibition 1.1%
Use shut-off nozzle, bucket, or low-flow spray
for irrigating areas not irrigated by irrigation
system.

Yes
2 Other - Customers must repair leaks,
breaks, and malfunctions in a timely
manner

0.8%
Repair within 72 hours of notification.

Yes
3 Landscape - Limit landscape irrigation
to specific days 6.6% Water limited to days assigned by CMWD (2 days/week). Yes
3 Other - Prohibit vehicle washing
except at facilities using recycled or
recirculating water

0.6%
No vehicle washing except at facilities that
recirculate water or use high pressure/ low
volume.

Yes
3 Other

1.7%
Suspension of consideration of annexations to
CMWD service area. Variable to meet
conservation need.

Yes
3 Other 1% Establish a water allocation for property served by CMWD Flexible depending on other actions;
adjust to meet 30% reduction. Variable to meet
conservation need.

Yes
3 Other - Customers must repair leaks,
breaks, and malfunctions in a timely
manner

1.7%
Repair within 48 hours of notification.

Yes
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DWR Table 8-3: Demand Reduction Actions
Shortage
Level
Demand Reduction Actions Shortage Gap
Reduction Value Additional Explanation or Reference Penalty, Charge, or Enforcement?
4 Water Features - Restrict water use for
decorative water features, such as
fountains

2.6%
Stop filing or re-filling ornamental lakes or
ponds, except to the extent needed to sustain
aquatic life.

Yes
5 Landscape - Prohibit certain types of
landscape irrigation 15.9%
No landscape irrigation unless recycled water
may be lawfully applied, with exceptions for
trees & shrubs using low-volume irrigation;
specific necessary landscaping.

Yes
5 Moratorium or Net Zero Demand
Increase on New Connections

2.9%
No new potable water service shall be
provided, no new temporary meters or
permanent meters shall be provided, and no
statements of immediate ability to serve or
provide potable water service shall be issued,
with the exception of the circumstances listed
in the Drought Ordinance.

Yes
5 Other - Customers must repair leaks,
breaks, and malfunctions in a timely
manner

3.4%
Repair within 24 hours of notification.

Yes
6 Landscape - Prohibit all landscape
irrigation 16.4%
No landscape irrigation unless recycled water
may be lawfully applied, with exceptions for
specific necessary landscaping.

Yes
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8.4 Catastrophic Supply Interruption
CMWD’s supplies are at risk for a catastrophic interruption because of its reliance on imported water to meet potable demands. While CMWD and SDCWA are both striving to reduce this dependence on imported water (through development of local supplies and increased recycled water use), the risk still exists that supplies will be interrupted in the event of a natural or man-made disaster.

Potential catastrophes to which CMWD’s supplies may be vulnerable include, but may not be limited to:
• Earthquake
• Fire/explosion
• Flood
• Tornado/severe weather
• Bomb threat
• Hard freeze
• Loss of normal water supply
• Hazardous material release
• Contamination of SDCWA or CMWD water supplies
• Terrorist attack
CMWD has taken several actions to prepare for, and implement, during a catastrophic
interruption of water supplies. In the event of a supply interruption, CMWD’s defined command chain dispatches crews to inspect infrastructure and critical operations.

Operations response crews are assigned to monitor system operations and modify operations as necessary, depending on the status of the system, the disaster, and needs.

The defined communication command chain coordinates with other local water agencies and emergency response officials as necessary. Criteria and procedures are provided to return system to normal operations, including initiating water quality testing when necessary and performing necessary emergency repairs to the system. The emergency operations plan contains contact information for responsible parties and support services.

Water shortage contingency plan stages will be implemented as required by the situation.

8.4.1 Seismic Risk Assessment and Mitigation Plan
CWC 10632.5 requires urban water suppliers to include a seismic risk assessment and mitigation plan to assess the vulnerability of each of the supplier’s various facilities of the water system and mitigate those vulnerabilities. An urban water supplier may also comply with this requirement by submitting a copy of the most recently adopted multi -hazard mitigation plan under the federal Disaster Mitigation Act of 2000 if the multi -hazard May 12, 2026
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mitigation plan addresses seismic risk. The City of Carlsbad assessed seismic risk in its 2023 Hazard Mitigation Plan as part of the County of San Diego’s Hazard Mitigation Plan submitted to the State of California Office of Emergency Services. The goal of the 2023 Hazard Mitigation Plan is to “reduce the possibility of damage and losses to existing assets, including people, critical facilities/infrastructure, and public facilities due to earthquakes.” Some of the action items for implementation included:
• Periodic updates to local building codes, public works construction codes, and zoning and grading ordinances
• Protect existing assets with the highest relative vulnerability to the effects of earthquakes
• Support existing efforts to mitigate earthquake hazards • Support community outreach efforts related to hazard mitigation • Support and maintain a comprehensive approach to reduce the possibility of damage and losses due to earthquakes
The Carlsbad Emergency Management Administrative Team has on -going funding to develop public awareness regarding hazard mitigation strategies and continue to develop and implement action items to meet the City’s earthquake goal. Appendix I includes the 2023 Hazard Mitigation Plan.

8.4.2 CMWD Emergency Storage of Water Policy
In addition, CMWD is included in SDCWA’s regional emergency storage plan (ESP), which plans and provides for regional supplies during a two -month and six-month emergency event. The regional emergency water supply reservoirs include Olivenhain with 18,000 AF of ESP capacity, Lake Hodges with 20,000 AF, and San Vicente with 52,100 AF. Actual amounts of ESP water to be delivered to each member agency are to be determined based on the specific emergency event. ESP supplies will depend on member agency demand, local supplies, infrastructure, availability of supplies, and duration of the emergency event.

SDCWA’s ESP is expected to provide a total of 90,100 AF of stored water which can potentially help meet regional water demands through 2050 (SDCWA 2026).

In addition, according to the City of Carlsbad emergency action plan, CMWD ’s local storage surplus is expected to be 5.49 MG in the distribution system which does not include the 195 MG Maerkle Reservoir. CMWD operates potable and recycled water storage for the purposes of regular operations, in addition to flexibility and planning for specific area outages or system wide outage. Overall, CMWD has sufficient storage to May 12, 2026
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meet operational and short-term emergency demand requirements under 2050 projected conditions.

8.5 Communication Protocols
CMWD’s communication protocol includes the various channels it will utilize to convey critical messages regarding water shortage allocations and voluntary and mandatory actions. A strong communication plan will educate CMWD ratepayers, local leaders and the business community, on the water supply situation; what actions are proposed; what the intended achievements are; and how these actions are to be implemented. While specific types of messaging are deployed at various shortage response levels, how these messages are conveyed to the public are described per this communication protocol. The communication protocol will be in place prior to a water supply shortage and be initiated in Shortage Level 1. Activation of the communication protocol will continue through all subsequent water shortage levels. At times, specific communities may require specialized outreach. CMWD will ensure outreach efforts are reaching key audiences as needed.

Per SDCWA’s 2025 WSCP, it is important to communicate to ratepayers the following when urgent conservation is needed:
• Specific actions needed to save water;
• How much water needs to be saved and for how long;
• Why water needs to be saved; and
• What CMWD is doing to correct the supply problem or address the situation.

8.5.1 Coordination
In order to communicate effectively, avoid confusion, and maintain credibility, CMWD will work in close coordination with SDCWA at various levels of management. These levels include the Joint Public Information Council/Conservation Coordinators (JPIC; staff level), the Member Agency Managers group (management level), and SDCWA Board’s Legislation and Public Outreach Committee (Board level). During droughts or other times of limited supply, the frequency and extent of coordination will increase to ensure outreach tactics are consistent with the changing needs of CMWD and its ratepayers.

CMWD will seek opportunities to leverage external resources to complement its own outreach.

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8.5.2 Communication Objectives
Communication objectives during the various water shortage levels of the WSCP include the following:
• Motivate water users to quickly increase conservation in ways that are consistent with any voluntary or mandatory actions called for at the current level of the WSCP. • Raise awareness and understanding of the drought, regulatory, or other condition affecting water supplies and the need for increased conservation. • Minimize confusion and maintain credibility of water agencies and conservation messages with an appropriate tone that carefully describes the current water shortage scenario.
• Make water users feel appreciated for existing accomplishments in improving their water-use efficiency, and for supporting regional and local investments in water supply reliability.
• Educate regional civic and business leaders, elected officials and the public about how CMWD has greatly improved its water supply reliability. • Prepare CMWD for any potential escalation (or de -escalation) of the WSCP based on trending supply conditions.
• Ensure all stakeholders believe they are being treated fairly in relationship to other stakeholders.
• Maintain communication effectiveness by soliciting or monitoring feedback from member agencies, key stakeholders, and the public to update or adapt messages or communication tools.
• Exit WSCP implementation having demonstrated the effectiveness and value of conservation actions and water supply reliability investments in minimizing impacts to the City of Carlsbad’s economy and quality of life.

8.5.3 Communication Protocol for Current Predicted Shortage A current or predicted shortage, as determined by the Annual Assessment, will be communicated to the public upon submittal of the Annual Assessment Report to the Board of Directors in June of any given year. Communication by Water Shortage Level is outlined in CMWD Water Code Title 3 and is described in the following subsections.

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Drought Response Level 1 (Drought Watch)
The existence of a Drought Watch condition may be declared by the Executive Manager upon a written determination of the existence of the facts and circumstances supporting the determination. A copy of the written determination shall be filed with the Secretary of the CMWD and provided to the CMWD Board of Directors. CMWD may publish a notice of the determination of existence of Drought Response Level 1 condition in one or more newspapers, including a newspaper of general circulation within the CMWD service area.

CMWD may also post notice of the condition on its website.

Drought Response Level 2 (Drought Alert) , 3 (Drought Critical) , or 4 (Drought Critical)
The existence of Drought Response Level 2 or Level 3 conditions may be declared by resolution of the CMWD Board of Directors adopted at a regular or special public meeting held in accordance with State law. The mandatory conservation measures applicable to Drought Response Level 2 or Level 3 conditions shall take effect on the tenth (10) day after the date the response level is declared. Within five (5) days following the declaration of the response level, CMWD shall publish a copy of the resolution in a ne wspaper used for publication of official notices.

Drought Response Level 5 (Drought Emergency) or 6 (Drought Emergency) The existence of a Drought Response Level 5 or 6 condition may be declared in accordance with the procedures specified in California Water Code sections 351 and 352.

The mandatory conservation measures applicable to Drought Response Level 5 or 6 conditions shall take effect on the tenth (10) day after the date the response level is declared. Within five (5) days following the declaration of the response level, CMWD shall publish a copy of the resolution in a newspaper used for publication of official notice s. If CMWD establishes a water allocation, it shall provide notice of the allocation by including it in the regular billing statement for the fee or charge or by any other mailing to the address to which CMWD customarily mails the billing statement for fees or charges for on-going water service. Water allocation shall be effective on the fifth (5) day following the date of mailing or at such later date as specified in the notice.

The CMWD Board of Directors may declare an end to a Drought Response Level by the adoption of a resolution at any regular or special meeting held in accordance with State law.

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8.5.4 Communication Protocol for Triggered or Anticipated to be Triggered Shortage Response Action
The public will be notified about triggered or anticipated to be triggered shortage response actions. The implementation of shortage response actions associated with any water shortage level will take effect on the tenth day after the date the shortage response action is declared. Within five days following the declaration of the shortage response action, the Executive Manager will publish a notice giving the extent, terms, and conditions around the use and consumption of water a minimum of one time for thr ee consecutive days in the City of Carlsbad’s official newspaper.

8.5.5 Catastrophic Communications
In the event of a catastrophic supply interruption that requires water use to be quickly prioritized for or limited to essential public health and safety needs, CMWD will immediately deploy appropriate strategies from Drought Response Levels 1 through 6. In addition, outreach messaging will reflect emergency conditions and the need to focus on health and public safety. CMWD may also consider potential joint news release/new events with public health officials or incident commanders to announce conditions and explain needed action. Finally, CMWD will ensure ongoing coordination with emergency response services with daily advisories or alerts as needed.

8.6 Compliance and Enforcement
When mandatory restrictions are in place, CMWD implements penalties for violations of the restrictions or prohibitions described above, as proscribed by CMWD Water Code Title

3. Each day that a violation occurs is considered a separate offense and administrative fines may be levied for each violation. For the first violation, CMWD will verbally notice the fact of the violation. For the second violation, CMWD will provide a written notice to the customer of the violation. For the third violation, CMWD may install a flow restricting device of one gallon per minute capacity for services of up to one and one -half inch size and comparatively sized restrictions for larger services upon a prior determination of multiple violations. Additionally, an administrative fine of $100 may be issued for the third violation. For a fourth violation within a one -year period, CMWD may issue a $200 administrative fine. Additional violations exceeding the fourth violation within a one-year period may result in a $500 administrative fine. Table 8-5 indicates the penalties for violation and at what stage they take effect.

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TABLE 8-5: CMWD PENALTIES FOR USE RESTRICTION VIOLATIONS Penalty Stage Trigger
Warning letter All stages First Violation
Notice of violation All stages Second Violation
Flow restriction installed All stages Third Violation
Administrative citations All stages
Third Violation ($100)
Fourth Violation ($200)
Fifth or More Violation ($500)
In lieu of administrative penalties as described above, when deemed appropriate and necessary, each violation may be prosecuted as a misdemeanor punishable by imprisonment for no more than thirty days or by a fine not to exceed $1,000, or by both.

All customers who incur a penalty due to violation of the Drought Ordinance in CMWD Water Code Title 3 have the right to appeal the penalty.

8.7 WSCP Revenue and Expenditure Impacts
In the event of a water emergency, the Drought Response would be activated to respond to the level of shortage. At that time, drought response stage actions would go into effect, and CMWD’s revenue is anticipated to decrease due to reduced water sales. The amount of decreased revenue would depend upon the response stage, and how long each stage is in effect. If revenues are less than required to meet CMWD’s financial obligations because of a water shortage, CMWD would draw from its operating reserves and then propose increasing water rates to appropriate levels for the Board’s consideration. The operating reserves are maintained at adequate levels to provide short-term operating capital in case of emergencies as well as provide for rate stabilization. Table 8-6 and Table 8-7 present how different actions and conditions impact revenues and expenditures, as well as provide a summary of potential actions that could be taken to address these impacts.

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TABLE 8-6: IMPACTS TO REVENUES AND METHODS TO ADDRESS IMPACT Potential Impacts to Revenues
Action Anticipated Revenue Impact
Rate
adjustment
No impact. This would be an administrative function to analyze rate structure options to offset potential losses in revenue associated with reduced sales.

Change in
quantity of
sales
Reduction in revenue expenses and associated reduction in quantity charge-based revenues generated to cover local O&M costs. Could be offset by a combination of budget reductions, expense deferrals, including some non-critical CIP projects, draws on rate stabilization and operating reserves, and rate adjustments.

Potential Solutions for Revenue Decreases
Action Anticipated Effects
Reserve
Fund
This option would have no short-term impact on the rate payers or CMWD because there are currently sufficient funds in CMWD’s operating reserves.

Change rate
structure
Minimal changes in rates could offset significant reductions in available water supplies.

Reduce
overhead
Overhead, or local fixed O&M costs, can be reduced in the short and mid-term by deferring selected cash-funded CIP and major maintenance projects, other expenditure reductions and if needed, hiring freezes.

Decrease
capital
expenditures
Deferral of selected, non-critical replacement projects will have little or no impact on CMWD or its customers and would only extend the duration of the master planned replacement schedule.

Infrastructure for new development is funded by new development and progresses at the rate needed by new development projects.

Revise
planning
estimates
If supply reduction were long-term, CMWD would make commensurate adjustments to its CIP schedule, staffing levels and retail rate structures based upon lower retail sales.

Impacts would be moderate and implemented over time.

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TABLE 8-7: I MPACTS TO EXPENDITURES AND METHODS TO ADDRESS IMPACTS Potential Impacts to Expenditures
Actions Potential Impacts
Change in quantity of
sales
Sales reductions could be offset with rate and budget adjustments and moderate CIP deferrals.

Increased
staff/salaries/overtime
No impacts. Existing staff would be re-assigned to perform functions required to implement and enforce consumption reduction methods and requirements.

Increased costs of new
supplies, transfers or
exchanges
SDCWA would secure new supplies whose cost would be melded into overall costs. Increased costs of wholesale water would be passed through to CMWD’s customers via rate increases and/or changes to the rate structure.

Potential Solutions for Expenditure Impacts
Action Anticipated Effects
Reserve Fund No impacts. The Replacement Fund is sufficient and exists for the very purposes anticipated in a supply shortage scenario.

Change rate structure Given the mix of wholesale water and power expenditures, non-commodity revenues needed to cover local fixed costs, availability of reserves and the flexibility to adjust CIP expenditures, no short-term (1 to 2 year) impacts are anticipated, mid-term (3 years) impacts would be moderate, and long- term (beyond 3 years) impacts would be moderate and incremental.

Reduce overhead In the short-term and mid-term, overhead or local costs can be reduced by deferring non-critical CIP and major maintenance expenditures. In the long- term, costs can be reduced by adjusting operational and staffing levels and retail water rate structures to incorporate the reality of lower retail water sales than previously anticipated.

Decrease capital
expenditures
In the short-term, there could be a decrease in the level of expenditures for CMWD’s replacement program, or an interruption of expenditures. In the mid- to long-term, the retail rate structure and the prioritization schedule would be adjusted to ensure that projects critical to service and system reliability were implemented.

Revise planning
estimates
If the reduced supply is determined to be a long-term condition, then commensurate adjustments would be incorporated into long-term staffing and water system facility requirements.

8.8 WSCP Monitoring and Reporting
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conservation requirements. Methods used by CMWD to determine actual reductions in water use are summarized in Table 8-8.

TABLE 8-8: METHODS FOR MEASURING WATER USE REDUCTIONS
Method for
Determining Actual
Reduction
Type and Quality of Data Expected
Use normalized or
average water use
baseline to determine
reductions
Each customer will be given a schedule of monthly use targets based upon the required reduction compared to the base period usage. Usage over the amount allocated for any given month will result in the customer incurring penalty pricing for usage that month. Usage under that amount will be accumulated to possible offset over-usage in successive month period.

More frequent review
of production
Water production is currently monitored on a real-time basis through CMWD’s SCADA system and reviewed on a daily basis.

More frequent meter
reading at customer
locations
Customer meters are read monthly which would coincide with the monthly allocation periods. Customers are given information on how to read their meter and monitor their own usage.

More frequent leak
detection and repair
Leak detection and repair is currently an active and ongoing O&M function, so no major changes would be expected.

System audit
The water system is currently audited on a monthly and annual basis, comparing metered deliveries from the SDCWA to metered deliveries to retail customers.

Automated sensors
and telemetry
CMWD has a SCADA system, which contains features to provide real-time monitoring and alarms communications to on-call operators to identify abnormalities in reservoir fill rates, draw-down rates, and pump function, which can be associated with system leaks and other malfunctions that could result in water loss.

Monitor utility actions
All CMWD actions are monitored and reported in a comprehensive Activities Report provided to the Board of Directors on an annual basis. Other types of staff reports on CMWD activities are given at the two regular Board Meetings each month or on as needed basis by the Executive Manager.

Penalties for customers
If and when penalty pricing is implemented, the amount and frequency of penalties would be monitored by the City of Carlsbad’s computerized billing system and then reported to the management staff and to the Board of Directors on a monthly basis.

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8.9 WSCP Refinement Procedures
CMWD will regularly review and update its WSCP to ensure that it remains aligned with evolving state requirements, regional supply conditions, and operational needs.

Consistent with California Water Code Sections 10632 and 10621(a)(4), water suppliers are required to maintain an up -to-date WSCP and refine it as conditions change or new information becomes available.

CMWD will initiate WSCP refinements under the following circumstances:
• Changes in regulatory requirements, including updates to the Water Code, DWR guidance, or statewide conservation mandates.
• Changes in supply reliability, such as updates from the San Diego County Water Authority, drought conditions, or emergency events.
• Post-implementation evaluation following activation of one or more shortage stages, where staff analyze the effectiveness of demand reduction measures, enforcement actions, and communication strategies.
• Integration of new infrastructure or operational capabilities, such as SCADA system upgrades, recycled water system expansions, or supply reliability enhancements within the City of Carlsbad’s water system.
• Lessons learned from regional coordination, including joint actions with SDCWA and neighboring water agencies.

Refinement activities may include updating shortage stage triggers, modifying demand reduction measures, refining communication protocols, adjusting estimated savings from shortage response actions, and incorporating updated supply and demand projections.

As required by state law, substantial WSCP revisions will be presented to the CMWD Board of Directors for adoption at a publicly noticed meeting. Once adopted, the updated WSCP will be submitted to DWR through the WUEdata portal and posted on CMWD’s website to ensure transparency and public accessibility. CMWD may revise its WSCP independently of the UWMP update cycle, allowing CMWD to respond rapidly to changing conditions.

8.10 Special Water Feature Distinction
The WSCP distinguishes non-recreational water features, such as ornamental fountains, artificial ponds, lakes, and waterfalls, from swimming pools and spas, which have separate health and safety requirements. Under Water Shortage Level 2, operation of deco rative water features is prohibited unless they utilize recirculated water. At Water Shortage Level May 12, 2026
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4, refilling of lakes or ponds is halted except as necessary to sustain aquatic life, provided that such animals are of significant value and have been actively managed within the water feature prior to the declaration of a drought response level.

Because non-pool water features may be designed to use recycled water, while pools and spas must rely on potable water, the WSCP applies different response actions, enforcement mechanisms, and monitoring approaches to each category.

8.11 Determination of Reliability
CMWD’s analysis indicates that, with continued reliance on SDCWA’s diversified supply sources, CMWD is anticipated to have sufficient water supply to meet projected demands under normal, single -dry, and multiple -dry year conditions throughout the 20-year planning period. CMWD’s water supply reliability is further supported by local operational measures, including system interconnections, storage capacity, demand management programs, expansion of recycled water use, and ongoing participation in regional drought-response initiatives.

In the event of supply reductions or emergency shortages, the WSCP provides a structured and adaptive framework for managing demand, maximizing available supplies, and maintaining essential service levels. SDCWA’s regional supply reliability and CMWD’s local planning efforts combined ensure that CMWD remains well-positioned to provide safe and reliable water service to its customers under a wide range of future conditions.

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9. DEMAND MANAGEMENT MEASURES
This section describes the past and current demand management measures (DMMs) undertaken by CMWD and quantifies, to the extent feasible, DMM efforts from 2021 through 2025.

9.1 Current Demand Management Measures
CMWD currently implements a variety of DMMs to manage customer demands. Together, these DMMs have contributed to CMWD’s success in reaching its SB X7-7 Targets (refer to Section 5 SB X7-7 Targets and Reporting) , have contributed to a more conservation - literate population, and positioned CMWD to align with new water use objectives. 1 9.1.1 Water Waste Prevention Ordinances
Title 3 of the CMWD Water Code includes the requirements from the two primary ordinances in place to prohibit water waste and encourage water use efficiency within its service area (Ordinance No. 44 – Drought Response Plan and Water Conservation Program and Ordinance No. 46 – Watering Schedules), which were both adopted in 2009.

On June 7, 2022, CMWD adopted Ordinance No. 48, which amended Ordinance No. 44 and No. 46 to better align its regulatory framework with changes at the regional and state level aroun d drought and conservation. CMWD Water Code Title 3, Chapter 3.12 (previously Ordinance No. 48) mirrors SDCWA’s 2020 Model Drought Ordinance and establishes a six -level Water Shortage Contingency framework, consistent with WSCP guidance from DWR ( Table 9-1). CMWD Water Code Title 3, Chapter 3.12 provides CMWD with the authority to declare water shortage levels based on regional supply conditions and to implement progressively stringent water conservation measures as shortages intensify. CMWD Water Code Title 3, Chapter 3.12 includes both permanent water-waste prohibitions and mandatory demand reduction actions tied to each shortage level, ensuring a structured and enforceable response to drought conditions. The ordinance modernizes and expands CMWD’s previous drought provisio ns by incorporating updated statewide requirements, improving consistency with the WSCP, and ensuring that CMWD can respond effectively to shortages of varying severity.

1 In 2018, California SB 606 and AB 1668 were enacted and expand authority to implement a water budget- based approach to conservation and water use efficiency. CMWD’s urban water use objective is based on calculated water budgets for residential indoor, residential outdoor, and commercial/industrial/institutional landscape use, as well as a variance for Carlsbad’s sizeable seasonal tourism population. In its most recent Urban Water Use Objective and Water Use Report, completed December 2025 for Fiscal Year 2 024-2025, CMWD’s reported water use was lower than its urban water use objective.

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For more details, refer to Section 8 Water Shortage Contingency Planning and Appendix I. CMWD maintains up-to-date information on current water use restrictions through the Water Rules page on its website: (www.carlsbadca.gov/departments/utilities/water/water- conservation/water-rules).

TABLE 9-1: DROUGHT RESPONSE LEVELS
Drought Response/ WSCP Levels Use Restrictions Conservation Target Level 1-Drought Watch Voluntary Up to 10%
Level 2-Drought Alert Mandatory Up to 20%
Level 3-Drought Critical Mandatory Up to 30%
Level 4-Drought Critical Mandatory Up to 40%
Level 5-Drought Emergency Mandatory Up to 50%
Level 6-Drought Emergency Mandatory Above 50%

9.1.2 Metering
All of CMWD’s water connections are metered and billed according to water consumed.

Some mixed-use meters where irrigation and domestic use were metered through one service connection meter in CMWD’s service area have been converted such that those properties’ irrigation systems use recycled water from the Phase III Recycled Water Project.

CMWD has a water meter replacement and calibration plan in place to ensure that meters are performing correctly, and all water consumed is being recorded. In general, CMWD replaces meters under 1 -inch every 20 years and meters over 1-inch every 15 years. I n 2012, CMWD began replacing traditional water meters with “smart meters” that enabled collection of water usage information to be automated. CMWD completed the final stage of its Advanced Metering Infrastructure (AMI) project in 2017.

9.1.3 Conservation Pricing
CMWD has and will continue to use a combination of uniform and increasing block or tiered rate conservation rate structures for potable water served. Single family and multi- family residential customer classes are billed in increasing block structures wher e the water rate increases for additional water units consumed. Since the 2020 UWMP was adopted, CMWD has updated its water rate structure to strengthen conservation incentives and reflect increasing water supply costs. While residential customers continue to be charged lower rates for essential water use (i.e., Tier 1) and higher rates for greater consumption (i.e., Tier 2), the price differential between lower -use and higher -use tiers has increased. Table 9-2 shows the approved residential customer billing rates for 2026.

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TABLE 9-2: 2 026 RESIDENTIAL CUSTOMER BILLING RATES FOR POTABLE WATER Tier Block Structure Cost per Unit1
Single Family and Master-Metered2
Tier 1 0 – 10 units $5.60/unit
Tier 2 Over 10 units $5.97/unit
Multiple Family2
Tier 1 0 – 5 units $5.59/unit
Tier 2 Over 5 units $5.80/unit
1 One water unit is 100 cubic feet or 748 gallons
2 Tiers are based on water use per dwelling unit, as measured in units of water consumed
Commercial, agricultural, and irrigation customer classes are billed using uniform rate structures where a flat rate is billed for every unit consumed. One unit is equal to a hundred cubic feet, or 748 gallons. Table 9 -3 shows the approved 2026 billing rates for commercial customers. Recycled water is billed by combining a monthly delivery charge based on water meter size with a usage charge of $4.63 in 2026.

TABLE 9-3: 2026 COMMERCIAL CUSTOMER BILLING RATES FOR POTABLE WATER Tier Cost per Unit1
Agricultural rate $5.84/unit
Irrigation rate $5.88/unit
Commercial rate $5.72/unit
1 One water unit is 100 cubic feet or 748 gallons

9.1.4 Public Education and Outreach
CMWD implements multiple approaches to public education and outreach on a variety of projects, initiatives, and goals. Through its ongoing commitment to customer service, much of this outreach is conducted through one-one-one interactions with customers in person, via phone and email inquiries. Formal programmatic approaches for outreach, workshops, school education programs, and provision of resources for CMWD customers are primarily through its partnership with the SDCWA as a member agency. Many of CMWD’s efforts are implemented in coordination with other agencies and through regional efforts. In addition, since 2020, CMWD customers removed approximately 244,244 square feet of turf through available rebate programs. Over that same time period, CMWD customers have received a total of 699 residential and 3,475 commercial device rebates.

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Outreach Activities
To reach a wide range of audiences, CMWD makes brochures and handouts available at various community centers and City of Carlsbad and CMWD offices. CMWD has consistently reached out to customers on at least a quarterly basis using various methods every quarter within the last five years. In coordination with SDCWA, CMWD promotes opportunities for residents to participate in regional programs such as the California– Friendly landscape contest, Speaker Bureaus, and Citizens Water Academy. As a member of the No rth San Diego Water Reuse Coalition, CMWD participates in outreach efforts educating the public on recycled water and potable reuse safety and use, and the importance of potable water conservation to the region.

Workshops
In coordination with SDCWA, CMWD provides workshops on water related themes geared to the residential user. Workshop topics presented in the past include California Friendly Landscape Training. Workshops are offered for free and held at different locations throughout the county, including within CMWD’s service area.

School Education
CMWD offers school education programs for local schools as well as education materials to teachers upon request through SDCWA. The Splash Lab offers assembly presentations available to grades 4 - 8 to educate students on water science. For grades K – 6, students can participate in an assembly that is fact-filled and engages students in water conservation. In addition, there is an annual calendar art contest for fourth graders from schools within CMWD’s service area with an opportunity to win prizes by drawing a water conservation themed picture.

Residential Customer Resources
In coordination with MWD’s SoCal Water$mart program and SDCWA’s WaterSmart San Diego County program, rebates are available to CMWD customers to promote indoor and outdoor water conservation. One popular program is the turf removal rebate program designed to encourage the replacement of water-thirsty turf for drought tolerant plants.

These programs are advertised and linked on CMWD’s water conservation website.

Through SDCWA’s turf replacement rebate program, CMWD customers have converted 82,554 square feet of turf to water -wise landscaping between 2020-2024. Table 9 -4 provides a list of all rebates available and their associated rebate amounts.

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TABLE 9-4: RESIDENTIAL WATER CONSERVATION REBATE
Rebate Program Name Rebate Amount
Indoor Rebates
Clothes washer rebate $85
HE toilets $40
Outdoor Rebates
Turf removal rebate $2-$3/sq ft up to 5,000 sq ft
Irrigation controllers $80
Irrigation nozzles $2/nozzle - minimum is 30
Rain barrels $35
Soil moisture sensors $35/controller station
Commercial Customer Resources
In coordination with MWD’s SoCal Water$mart Program and SDCWA’s WaterSmart San Diego County program, CMWD provides information on available rebates for CMWD’s commercial customers that promote water efficiency for businesses. Table 9-5 displays the rebates and their associated amounts available to commercial customers that were available in recent years.

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TABLE 9-5: COMMERCIAL WATER CONSERVATION REBATES
Rebate Name Rebate Amount
Indoor Fixtures
HE toilet $40
UL Urinal $200
Zero Water urinal $200
Flow valve restrictions $5/valve (minimum of 10)
Outdoor Fixtures
Turf removal $2/sq ft up to $5,000
Irrigation controllers $35/controller station
Irrigation heads $2/nozzle (minimum of 30)
Large rotary nozzles $13/set (minimum of 8)
Flow regulators $1/regulator (minimum of 25)
Soil moisture sensors $35/station
Restaurant Fixtures
Connectionless food steamers $485
Air-cooled ice machines $1,000
Commercial/Industrial
Cooling tower conductivity controllers $625
Cooling tower pH controllers $1,750
Dry vacuum pump $125/0.5 HP
Laminar flow restrictors $10/restrictor (minimum of 10) Large Landscape Water Audits
Dedicated Large Landscape customers are offered water audits to provide suggestions on improving water efficiency and to qualify for water conservation rebates through the SDCWA. In the past five years, approximately four water audits have been performed for CMWD customers by an independent contractor.

Contractor Incentive Program
The WaterSmart Contractor Incentive Program offers several incentivized water -efficient devices that, when installed in combination, are among the irrigation industry’s best management practices. Program requirements, qualifying irrigation devices and rebate amounts are available from SDCWA.

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WaterSmart Check-Up Program
Through SDCWA, CMWD offers the WaterSmart Check -up Program to top water users each month. During a WaterSmart check-up, a WaterSmart certified irrigation professional visits a property upon request to provide water saving tips and perform a water audit. This audit includes an inventory of water fixtures used indoors and outdoors, replacement of high use water fixtures, evaluating toilets for leaks, and performing a landscape water audit. During the water audit, sprinkler stations are turned on to evaluate i nefficiencies and adjustments to watering schedules are made where appropriate. A summary report with additional conservation advertising is left with the customer at the end of the appointment. From 2020-2024, 72 audits were performed.

Landscape Education
WaterSmart Landscaping in San Diego County is an online plant finder found at www.cawsandiegogardening.com, promoted on the SDCWA landscape website at www.watersmartsd.org/residencial/landscape-resources. This interactive gardening tool has thousands of pi ctures of plants and garden designs that are well -suited to the southern California climate. It offers visual tours of beautiful, water -efficient landscapes through photographs with links to plant information screens. CMWD Is working with City of Carlsbad Planning on their current review and plan to update its Landscape Manual to reflect changes in water use efficiency regulations over the preceding 5 -year UWMP timeframe.

WaterSmart Landscape Makeover Program Workshops
These workshops offer classes and coaching from professionals that teach the basics on how to do a landscape makeover. Topics include soil, design, turf removal, plant selection, planning, irrigation, rainwater catchment and implementation, which are all the elements needed to convert high-water-use turf to a beautiful, water-efficient landscape.

Quality Water Efficient Landscaper (QWEL)
On the WaterSmart website, people can register for free local training courses that will result in Quality Water Efficient Landscaper (QWEL) certification. Providing landscape professionals with 20 hours of education on principles of proper plant selection for the local climate, irrigation system design and maintenance, and irrigation system programming and operation.

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Agua Hedionda Lagoon foundation (AHLF) Demonstration Garden In the City of Carlsbad, the AHLF hosts the premiere native plant garden in North San Diego County. Visitors can browse through the extensive California Native Plant Garden and accompanying colorful and informative interpretive signage. The landscaping includes 800 native plants featuring over 60 different species for visitors to learn about California's low water use native flora.

9.1.5 Programs to Assess and Manage Distribution System Real Loss CMWD has completed the AWWA Water Loss Audit Software program and has determined that water losses are within the acceptable industry standard range. Water losses have been incorporated into the appropriate tables in Section 4 Water Use. CMWD is proactive in reducing unaccounted for water by ensuring water meters are regularly maintained, evaluated for functionality, and replaced well within industry standards.

Reported leaks are investigated and recorded in a tracking database that collects the time of report, leak location, and type of leaking pipe or fitting. Leaks are repaired to the extent that it is cost effective and prioritized based on potential water loss.

CMWD also uses the Supervisory Control and Data Acquisition (SCADA) system, a meter replacement program, and AMI with WaterSmart technology to minimize leaks and water waste. These programs help customers conserve water by updating technology and replacing meters to help better monitor leakage.

9.1.6 Water Conservation Program Coordination and Staffing Support CMWD no longer employs a full -time (1 FTE) Water Conservation Specialist and a Supervisor at 25% FTE. An overview of CMWD’s Water Conservation programs can be found at: www.carlsbadca.gov/departments/utilities/water/water-conservation.

9.2 DMM Activity
From 2021 through 2025, CMWD continued implementing all required DMMs, maintaining updated operational practices under Ordinances 44 and 48 and ensuring all customer accounts remained fully metered with commodity -based billing. Tiered conservation pricing persisted throughout the period, alongside consistent delivery of water-use surveys and both residential and commercial rebate programs supporting indoor and outdoor efficiency improvements, including turf replacement. School education programs continued each year, with direct field trips offered through 2023 and annual funding allocations maintained thereafter as budget allowed, collectively May 12, 2026
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demonstrating CMWD’s ongoing commitment to comprehensive water -use efficiency and conservation.

Looking ahead to 2026–2030, CMWD will continue operating under CMWD Water Code Title 3, Chater 3.12 (previously Ordinance No. 48), conduct timely leak repairs with a full system leak survey planned for 2027, and maintain universal metering supported by system-wide advanced metering infrastructure. Tiered rates and school education program funding will continue.

9.3 Future DMM Implementation
CMWD will continue to provide information about the available array of educational and rebate programs, as funds are available to sustain the programs. The popularity of SDCWA’s Turf Removal Rebate displays a need and desire for residential customers wanting permanent options to manage outdoor water use. Although all fixtures for indoor conservation that are now available to California customers are water efficient, CMWD still sees the rebate program as a way to continue to encourage additional conservation through high efficiency devices as coordinated through the SDCWA program.

As demonstrated in Section 5 SB X7 -7 Targets and Reporting, CMWD’s 2020 GPCD was well below its 2020 target. These savings have been achieved in part due to implementation of the DMMs described in this section, and CMWD is committed to continued demand management through ongoing perma nent savings (e.g., from landscape conversions), water waste prohibition and waste prevention ordinances, expansion of recycled water service, education and other conservation efforts.

As part of the regulatory requirements for establishing and reporting the UWOU, CMWD is mapping its outdoor irrigated landscaped areas. Residential landscape area measurements (LAM) were mapped and quantified by the State in 2021 and values provided to all water suppliers. This landscape measurement is used in calculating CMWD’s budget for residential outdoor irrigation use based on new and progressively more restrictive standards. Water suppliers are also required to map and measure outdoor landscape irrigated by dedicated irrigation meters (DIMs) for commercial, industrial and institutional (CII) customers, by 2028, as well report data in high water for various percentages of water users in this sector. CMWD contracted with the consulting company responsible for creating the Residential LAM data and maps, to map the CII DIMS LAM and also invested in their water management tracking program WaterView. This tool will assist in tracking customer use and can be used to create conservation campaign information and targeted outreach based. CMWD expects to use this program to develop regular and more targeted conservation outreach.

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10. PLAN ADOPTION, SUBMITTAL, AND IMPLEMENTATION
This section of the 2025 UWMP addresses the steps CMWD will take to adopt the 2025 UWMP, submit it to DWR, and outlines the steps that will be taken should it prove necessary to amend the 2025 UWMP.

10.1 Plan Review and Notification Process
CMWD encouraged community and public involvement in the 2025 UWMP by releasing a draft UWMP for public comment and scheduling a public hearing. The draft was released on March 11, 2026. The public hearing is May 12, 2026. This provides an opportunity for CMWD’s customers, interested agencies and organizations, and the public to learn about CMWD’s current and projected water supply situation, and plans to continue to provide a reliable water supply in the future. The hearing is an opportunity for people to ask questions regarding the current water reliability situation and the viability of future plans.

The hearing i ncludes a discussion of CMWD’s WSCP and associated annual reporting procedures, as well as CMWD’s SB X7-7 per capita water use targets and achievement of the target by 2020.

A 60-day notice of the update to the UWMP and public hearing was provided to San Diego County and adjacent cities and other entities on March 9, 2026. The notification list has been included in Appendix A, and notified agencies, cities, and the county are listed in Table 2-5, along with their level of involvement with plan development.

TABLE 10-1: NOTIFICATION TO CITIES AND COUNTIES
DWR Table 10-1 Retail: Notification to Cities and Counties City Name 60 Day Notice Notice of Public Hearing
City of Carlsbad

County Name 60 Day Notice Notice of Public Hearing
San Diego County

Public hearing notifications were published in the San Diego Union Tribune on April 28 and May 5, 2026. A copy of the draft 2025 UWMP was made available for public review 30 days before the public hearing on the City of Carlsbad’s website at www.carlsbadca.gov. Hard copies are available for review at City offices. C opies of the published notices are included in Appendix A.

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Chapter 10: Plan Adoption, Submittal and Implementation 10-2

10.2 Plan Adoption and Submittal Process
CMWD’s Board of Directors will hold a public hearing to receive public comments on the UWMP, immediately prior to adoption of the UWMP. Following the public hearing on the document, this Plan is also scheduled to be adopted by the Board of Directors on May 12, 2026 with a provision that the CMWD Executive Manager is authorized to approve any minor plan revisions or edits resulting from the hearing. A copy of the adoption resolution will be provided in Appendix B.

The 2025 UWMP will be submitted to DWR, the California State Library, and San Diego County within 30 days after adoption, prior to the CWC’s deadline of July 1, 2026.

Submitted items include an electronic copy of the 2025 UWMP, along with copies of the required tables submitted through the WUE data online submittal tool to DWR, and one CD with an electronic copy to each of the California State Library and San Diego County, in accordance with the requirements in the 2025 Guidebook. The 2025 UMWP will be available for public review on the City of Carlsbad’s website within 30 days of filing a copy with DWR, or by July 30, 2026.

10.3 Plan Implementation
All data used in development of this UWMP are the most current data available, and unless otherwise noted, include data for the calendar year. CMWD shall implement the adopted 2025 UWMP in accordance with the schedule described in this Plan. Any future amendments made to this Plan will require completion of the same series of notification, public hearing, adoption, and submittals as required in submittal of the adopted 2025 UWMP.

10.4 WSCP Adoption, Submittal and Availability
The final WSCP is included in the adoption of the 2025 UWMP, as described in the previous sections. However, the WSCP can be amended, as needed, outside of a UWMP update cycle. The processes for approving WSCP amendments and conducting required public hearings are similar to those required for UWMP adoption. CMWD would release a 60-day notice of a public adoption hearing for the amended WSCP. The list of entities that would be notified are provided in Appendix A. The public hearing to receive public comments on the amended WSCP would be held immediately prior to the adoption of the amended WSCP by the Board of Directors. The amended WSCP would be made available for the public on the City of Carlsbad’s website within 30 days of the adoption date
.

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Chapter 11: References 11-1

11. REFERENCES
Bureau of Reclamation. 2026. Colorado River Post 2026 Operations. U.S. Department of the Interior. https://www.usbr.gov/ColoradoRiverBasin/post2026/index.html.

Carlsbad Municipal Water District (CMWD). 2019. 2019 Potable Water Master Plan.

Carlsbad Municipal Water District (CMWD). 2019. 2019 Recycled Water Master Plan.

Carlsbad Municipal Water District (CMWD). 2024. Project No.: C-067899-110 Phase III Recycled Water Project Quarterly Report, Reporting Period January 1 – March 31, 2024.

Carlsbad Municipal Water District (CMWD). 2025. Project No.: C-067899-110 Phase III Recycled Water Project Project Completion Report. December.

Carlsbad Municipal Water District (CMWD0. 2011. 2010 Urban Water Management Plan.

City of Carlsbad. 2024. Climate Action Plan Update.

City of Carlsbad. 2024. General Plan Land Use and Community Design Element.

City of Carlsbad. 2024. Land Use Designation GIS data. September. Available online at:
https://open-data-
carlsbad.hub.arcgis.com/datasets/261c6732fb77436e8614c76f1976630f_0/explore.

City of Carlsbad. 2024. Carlsbad Municipal Water District Ordinance List and Disposition Table. Available online at: https://ecode360.com/45344881.

City of Carlsbad. 2025. Fiscal Year 2023-2024 Growth Management Program Monitoring Report.

City of Carlsbad. 2025. Water, Sewer, Recycled Water Rates. Available:
https://www.carlsbadca.gov/departments/utilities/rates.

City of Carlsbad. 2026. Water Conservation. Available online at:
https://www.carlsbadca.gov/departments/utilities/water/water-conservation.

City of Carlsbad. N.d. Resident Resources. Available online at:
https://www.carlsbadca.gov/departments/environmental-sustainability/clean-ocean- lagoons/residents.

City of Carlsbad. N.d. Water Conservation. Available online at:
https://www.carlsbadca.gov/departments/utilities/water/water-conservation.

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Chapter 11: References 11-2
City of Carlsbad. N. d. Carlsbad Municipal Water Code. Available online at:
https://ecode360.com/45344879
Data from the National Oceanic Atmospheric Administration’s (NOAA) climate station at the McClellan Palomar Airport. 2026.

Department of Water Resources. 2020. DAC Mapping Tool.

Department of Water Resources. 2025. Urban Water Management Plan Guidebook 2025 Encina Wastewater Authority. 2025. Fiscal Year 2024-25 Annual Comprehensive Financial Report. Encina Wastewater Authority.
https://www.encinajpa.com/images/Fiscal_Year_2024-
25_Annual_Comprehesive_Financial_Report.pdf.

Encina Wastewater Authority. 2025. Fiscal Year 2025-26 Operating & Capital Budget.

Available online at: https://www.encinajpa.com/images/Fiscal_Year_2025- 26_Operating__Capital_Budget.pdf.

Leucadia Wastewater District. 2026. Service area map.
https://www.lwwd.org/about/service-area-map.

Metropolitan Water District of Southern California. 2025. Regional Urban Water Management Plan.

National Oceanic Atmospheric Administration’s (NOAA). 2026. Climate station data at the McClellan Palomar Airport.

North San Diego Water Reuse Coalition. 2020. North San Diego Water Reuse Coalition Regional Recycled Water Project. Available online at: http://nsdwrc.org/.

San Diego Association of Governments (SANDAG). 2024. Series 15 Regional Forecast, City of Carlsbad. July.

San Diego County Water Authority (SDCWA). 2025. Southern California water agencies end lengthy legal dispute. https://www.sdcwa.org/mwd-sdcwa-settlement.

San Diego County Water Authority (SDCWA). 2026. Technical Draft 2025 Urban Water Management Plan. January.

San Diego County Water Authority (SDCWA). N.d. Conservation WaterSmart SD website.

Available: www.watersmartsd.org.

Woodard & Curran. 2025. CMWD Annual Population Projects, 2025-2050. April 2.

Woodard & Curran. 2025. Seasonal Population Variance Analysis Technical Memorandum. September 8.

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APPENDIX A: NOTIFICATION

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Docusign Envelope ID: B59C0B04-D741-436B-B590-41CAEE92C366 Ca
rlsbad Municipal Water District
5950 El Camino Real  Carlsbad, CA 92008  442-339-2722  www.carlsbadca.gov March 9, 2026
Carls
bad Municipal Water District
5950 El Camino Real
Carlsbad, CA 92008
Thi
s letter is to inform you that Carlsbad Municipal Water District (CMWD) is updating its Urban Water Management Plan (UWMP) and Water Shortage contingency Plan (WSCP). California state law requires each urban water supplier to prepare and adopt a UWMP and WSCP every five years.

The 2025 UWMP documents CMWD’s plans to ensure adequate water supplies to meet existing and future demands for water over at least 20 -year period under a range of water supply conditions. California state law requires every urban water supplier to prepare and adopt a water shortage contingency plan as part of its UWMP that details how the supplier intends to act in the case of a water shortage condition. CMWD must adopt and update UWMP and WSCP, which is a chapter in the UWMP, in June 2026 in order to submit the adopted plan to the California Department of Water Resources by July 1, 2026.

Co
nformance with California Water Code Division 6, Part 2.6, §10621, this letter serves as a notification to all city and county agencies within which CMWD provides water supplies that the UWMP and WSCP are being reviewed and updated. The draft 2025 UWMP and draft WSCP will be available for public review on the City of Carlsbad website ( www.carlsbadca.gov) by Wednesday, March 11, 2026. Notice is hereby given that Tuesday, May 19, 2026, date has been rescheduled to Tuesday, May 12, 2026, at 5:00 P.M. at the City Council Chambers, 1200 Carlsbad Village Drive, Carlsbad, California 92008, the Board of Directors of CMWD will conduct a public hearing on the 2025 UWMP and WSCP and consider for adoption. The adopted 2025 UWMP and WSCP will be submitted to the California Department of Water Resources by July 1, 2026.

If y
ou would like additional information, please contact Keri Martinez, District Engineer, at 442 - 200-7376 or [email protected], or myself at 442-339-5485.

Sinc
erely,
Amand
a L. Flesse
General Manager
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Olivenhain Municipal Water District
Kimberly Thorner
General Manager
1966 Olivenhain Road
Encinitas CA 92024
Rincon del Diablo MWD
Clint Baze
General Manager
1920 North Iris Lane
Escondido CA 92026
San Elijo Joint Powers Authority
Mike Thornton
General Manager
2695 Manchester Avenue
Cardiff-by-the-Sea CA 92007
San Diego County Water Authority
Jeff Stephenson
Director of Water Resources
4677 Overland Avenue
San Diego CA 92123
San Diego Association of Governments
Antoinette Meier
Senior Director of Regional Planning
1011 Union Street Suite 400
San Diego CA 92101
City of Encinitas
Scott Drapkin, Director Development
Services
505 S Vulcan Avenue
Encinitas CA 92024
County of San Diego
Vince Nicoletti Director,
Dept of Planning
5510 Overland Avenue Suite 210
San Diego CA 92123
City of San Diego
Heidi Vonblum, Director
Planning
202 C Street M.S. 413
San Diego CA 92101-4806
City of San Marcos
Joseph Farace
Planning Division Manager
1 Civic Center Drive
San Marcos CA 92069
San Diego Local Agency
Formation Commission
Keene Simonds, Executive Officer
2550 Fifth Avenue Suite 725
San Diego CA 92103
City of Carlsbad
Don Neu
City Planner
1635 Faraday Avenue
Carlsbad CA 92008
Vallecitos Water District
James Gumpel
General Manager
201 Vallecitos De Oro
San Marcos CA 92069
Vista Community Development Dpt
Joe Vacca
Director
200 Civic Center Drive
Vista CA 92084
Encina Wastewater Authority
Scott McClelland
General Manager
6200 Avenida Encinas
Carlsbad CA 92011
City of Escondido
Christopher W. McKinney
Director of Utilities
201 N Broadway City Hall, Second Floor
Escondido CA 92025
City of Oceanside Frederick Mayor
Water Utilities Director
300 N Coast Highway
Oceanside CA 92054
Leucadia Wastewater District
Paul J. Bushee
General Manager
1960 La Costa Avenue
Carlsbad CA 92009
MWD of Southern California
Shivaji Deshmukh
General Manager
P.O. Box 54153
Los Angeles CA 90054-0153
Santa Fe Irrigation District
Al Lau
General Manager
P.O. Box 409
Rancho Santa Fe CA 92067

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APPENDIX B: UWMP ADOPTION RESOLUTION (TO BE INCLUDED IN FINAL)

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APPENDIX C: UWMP CHECKLIST

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Carlsbad City CouncilMay 12, 2026

Carlsbad City Council
May 12, 2026