Our Mission and History

It is our mission to provide a diversified, sustainable water supply for water service to our Pauma Valley customers that exceeds all standards of quality and reliability at fair, reasonable, and equitable rates.


The Yuima Municipal Water District (“Yuima” and/or “District”) was organized on January 19, 1963 under the Municipal Water District Act of 1911. The organization was needed for the prime purpose of importing Colorado River water to the areas populated mostly within the mutual water companies existing in the Pauma Valley area (Palomar Mutual Water Company later known as Improvement District "A"; Rancho Estates Mutual Water Company; Rancho Pauma Mutual Water Company; and Lazy H Mutual Water Company) in order to augment their local water supplies. The District takes its name from a creek tributary to the River, which means "Snow Water" in the Native American Language.


Yuima encompasses 13,460 acres (21 square miles) which includes the following lands in Pauma Valley:

  • District owned watershed land - 1,126.77 acres (encompassing Assessor Parcel Nos. 132-270-42 (645.70 acres); 132-100-17 (481.07 acres); and 32.31 acres of other District owned lands.
  • Wilderness Garden area - 679.1 acres.
  • Indian Reservation land - 564.85 acres. Reservations include Yuima Reservation and Pala Mission Tribes.
  • Taxable lands - 10,271 acres. Yuima’s taxable acreage consists of approximately 986 parcels.
  • Zero value & non-taxable parcels – 690.67 acres. These include easement parcels, churches, community center, open space easements, homeowners associations, state owned lands, and Pauma Elementary School.

The District encompasses several mutual water companies:

     •   Rancho Pauma Mutual Water Company (P.V. Country Club) which has an area of approximately 1,105 acres.

  • Rancho Estates Mutual Water Company (Adams Drive area) which has an area of 490 acres upon which 416 shares of stock are issued.
  • Lazy H Mutual Water Company (Lazy H Drive area) which has an area of approximately 35.4 acres.
  • Pauma Ridge Mutual (West of Adams Drive) which has an area of approximately 453.73 acres.
  • Rincon Oaks Water Service (Water Mountain Ranch area) formed with CC&R's on deeds which encompass an area of approximately 294 acres.
  • Three Party Water Company (Borden/Hegardt/Borden properties) formed with CC&R's which encompass an area of approximately 100 acres.

The District also encompasses two community services districts:

•   Rincon Ranch Road Community Services District - road district.

•   Pauma Valley Community Services District - sewer and security services in the vicinity of the Pauma Valley Country Club area.

The District's boundaries are adjoined by Mootamai Municipal Water District (401.8 acres), Pauma Municipal Water District (4,323 acres), and Valley Center Municipal Water District to the West. Palomar Mountain State Park is 16 miles from the District, and the Famous Wilderness Gardens is located in the District together with the renowned Pauma Valley Country Club (Club).

Mootamai Municipal Water District is a non-operating water district, which provides fire services only.   Pauma Valley Water Company operates a Mutual Water Company within portions of Mootamai boundaries.

The area is unique in many ways due to its varying elevations, private water companies and high rate of irrigation.

Areas Excluded From the District

Some areas in the Pauma Valley were excluded from the District prior to its formation because landowners believed they had an adequate supply of their own. These areas are known as Mootamai Municipal Water District and Pauma Municipal Water District.


The population of Pauma Valley is approximately 1,350. Approximately 350 people are served on a regular basis. Others either have their own private water supply or are supplied by the mutual water companies in Yuima's boundaries and have standby connections in the event of well failures or demand exceeds their pumping abilities. An additional 1,000 people are reliant upon Yuima's water service on a stand-by basis through existing meter connections.

Water Supply

Prior to Yuima’s formation in 1963, the sole source of water was the San Luis Rey River’s Pauma Groundwater Basin. Following a period of drought extending back to 1949, coupled with increased agricultural water demands, the water table fell drastically and overdrafts of the underlying Pauma Groundwater Basin lowered groundwater levels as much as 85 feet, forcing the abandonment of some wells and giving rise to increased pumping costs.

The drought also led to a stipulated judgment in the case of Strub et al. vs. Palomar Mutual Water Company. This judgment limited Palomar Mutual to withdrawal of no more than 1,350 acre-feet per year from wells in the Pauma Groundwater Basin (below 1,000 ft above mean sea level and upstream of Cole Grade Road) for use on the lands it served. After annexing Palomar Mutual in 1964, Yuima became successor in interest to Palomar Mutual and continues to operate the former Palomar Mutual system and properties (now known as Improvement District A) as an independent water system (California State System No. 3700938). Yuima is responsible for administering IDA’s compliance with Strub et al., which however does not affect or bind the 60% of the District which is outside of IDA and which operates under a separate system permit (System No. 3701408).

Voters approved the sale of general obligation bonds in 1963 concurrently with the annexation of the District to both the San Diego County Water Authority (“Water Authority”) and the Metropolitan Water District of Southern California (MWD) in order to receive imported water. These bonds were paid off in 1989.

Imported Water Distribution Network

Metropolitan Facilities

Colorado River supplies are transported from Lake Havasu through the Colorado River Aqueduct to Diamond Valley Lake and then to Lake Mathews in Riverside County. Before reaching Lake Mathews, a portion of the water is delivered through the San Diego Canal to Lake Skinner, the major storage facility for San Diego where it is treated.

State Water Project supplies are delivered to Lake Perris, which is the terminus of the 444-mile California Aqueduct. It is then blended with Colorado River water in the San Diego Canal where it flows into Lake Skinner. MWD delivers a blend of Colorado River Water and State Project Water. The percentage derived from each of the two sources varies from year to year, depending on hydrologic, environmental, and political factors.

The MWD Act provides a preferential right for the purchase of water by each of its constituent agencies. The preferential right is calculated using a formula. Based on the formula, the Water Authority has a statutory preferential right to approximately 18.11 percent of MWD’s total supply as of June 30, 2014. MWD has represented that it will provide reliable water supplies notwithstanding preferential rights.

Water Authority Facilities

The San Diego County Water Authority (Water Authority) was organized on June 9, 1944 under the County Water Authority Act (Act). The Water Authority’s primary purpose is providing wholesale water to its member agencies for domestic, municipal, and agricultural uses. The Water Authority consists of 24 member public agencies that are each represented by at least one person the Water Authority’s Board of Directors.   The Water Authority is a member of the Metropolitan Water District of Southern California (MWD). Historically, the Water Authority purchased all the water it required from MWD to meet the demand of the member agencies. The Water Authority has been in the process of diversifying its supply. Pursuant to the Quantification Settlement Agreement (QSA), signed October, 2003, and its related contracts, the Water Authority is obtaining conserved water from the Imperial Irrigation District (IID) and will also receive water conserved by the lining of the All-American and Coachella Canales. The Water Authority also adopted a Regional Water Facilities’ Master Plan in 2004 that calls for further supply diversification.

Water Authority takes delivery of water from MWD through five primary pipelines buried in two rights of way called the San Diego Aqueducts. The delivery points are located about six miles south of the Riverside-San Diego County line. From there, water is distributed through more than 279 miles of pipeline to Water Authority’s 24 member agencies through 119 service connections to serve 2.7 million residents in San Diego County[1].

The Water Authority does not own any storage facilities. However, it does have storage agreements with the City of San Diego, Ramona, and Sweetwater. It has recently implemented an Emergency Storage Project (ESP), a system of dams, reservoirs interconnected pipelines and pumping stations designed to make water available to the San Diego region in the event of an interruption in imported water deliveries. The ESP is projected to meet the county’s emergency needs through 2030 and will add 90,100 acre-feet of reservoir capacity for emergency use within the county. It includes the 318-foot-high Olivenhain Dam and 24,000 acre-foot reservoir (completed in 2003); a pipeline connecting the new Olivenhain Reservoir to the Water Authority’s Second Aqueduct (completed in 2002); a pipeline connecting the new Olivenhain Reservoir with Lake Hodges (under construction); a pipeline connecting San Vicente Reservoir to the Water Authority’s Second Aqueduct (under construction); raising the San Vicente Dam 117 feet to provide additional water storage (completed in 2014); five new pump stations; and related facilities[2].

Yuima Connection

Yuima is served off the First Aqueduct, Pipeline No. 1 near Couser Canyon Road in Valley Center just north of Lilac Tunnel and receives treated water from Lake Skinner. Our water operators communicate with the Authority and make delivery requests twice daily following our estimated flow demands in excess of our local water delivery ability. Because these connections can access only treated water supplies from the Skinner Treatment Plant, Yuima’s total access to imported water is affected by the capacity limitations of Skinner, which has operated recently at or near its design capacity.


Rainfall measurements are taken at the top of Quail Drive (Barrett) historical data until 2010, Rincon Ranch Road at 2,055’ elevation and at the Yuima office on Valley Center Rd. (Appendix “B”). Rainfall over the past ten years, though only slightly below the long-term average for the region, has been insufficient to maintain static water levels in the Pauma Basin portion of the San Luis Rey River watershed from which Yuima draws most of its local water.

Water Authority Board Representation

Yuima is entitled to one representative on the San Diego County Water Authority (“Water Authority”) Board. Presently the District’s representative is Ron W. Watkins. The Water Authority, in turn, appoints four (4) representatives on Metropolitan Water District’s (MWD) Board.

Imported Water Costs

MWD’s Skinner Filtration Plant, with a capacity of 340 MGD, serves a portion of the treated water requirement of CWA. Yuima began receiving treated water in 1991 from MWD, via the Water Authority’s pipeline facilities. Prior to this time, Yuima received raw Colorado River water. Skinner Filtration Plant was unable to serve Yuima filtered water prior to 1991 due to a needed cross-over pipeline between the filtered and the raw water lines and the lack of capacity at the plant. With the cross-over and the expansion of the plant completed in April 1991, Yuima began paying approximately $40 per acre-foot more.

In October of 2008 the CWA Board approved a two-year transitional special agricultural water rate (SAWR) for customers opting out of the Metropolitan Water District's Interim Agricultural Water Program (IAWP). As part of the phase-out of the IAWP, MWD provides IAWP customers the option of annually opting out of the program. CWA's transitional SAWR was to terminate December 31, 2010 but was extended to December 31, 2012 to coincide with the IAWP. The SAWR program is currently being studied by the CWA workgroup to develop options to either; 1) discontinue the special agricultural rates, 2) continue with the transitional program, or 3) adopt a new special agricultural rate program. Water delivered to certified agricultural (TSAWR) users represents 78% of the District’s total combined water sales.  Our ability to continue to meet a portion of our demand with lower cost local supplies is a major reason for the continued viability of agriculture in the District. Diversification of water supply sources reduces the District’s operational risk and reliance on the SDCWA as a primary source of water supply.


The District employs nine (10) full-time employees.

Lazy H Mutual Water Company. Yuima also handles, under contract, bookkeeping and secretarial services for the Upper San Luis Rey Watershed Authority and has Service Agreements with the Pauma Valley Mutual Water Company and the Rancho Estates Mutual Water Company.

Yuima also administers a Joint Powers Agreement between Yuima, Mootamai and Pauma Municipal Water Districts to provide fire protection services. Yuima was successful in implementing a Joint Powers contract with the State of California to provide fire protection services under the Amador Plan. This extended our ability to finance fire protection past the year 1985 when the voter-approved fire tax was estimated to become inadequate. Yuima also collects fire mitigation fees from new construction which can only be used for capital expenditures related to fire protection, services which are currently provided under a contract with the California Department of Forestry.

On February 23, 2009, Yuima through the Joint Power Agreement completed the construction of an Apparatus Building at the CDF station in Pauma Valley. The total cost of the building was $268,000. It was funded with Fire Mitigation Fees collected over the past 20 years from new construction.

Funding Methods

New development requires the expansion of existing facilities or the construction of additional facilities. In addition to the general types of funding mechanisms available for all types of facilities, there are a number of different kinds of fees that can be used for the financing of water transmission facilities. These include capacity charges, water consumption charges, stand-by or water availability charges, and fixed meter charges. Legislation authorizing the establishment of the different types of water districts gives Yuima the authority to impose charges and rates for services and facilities. The County has no control over the funding of facilities owned by Yuima.

Yuima collects a capacity charge fee when a new meter is installed based on the size of the meter (in Yuima’s general district only - no capacity charge is currently charged past master meters). Improvement District A collects its capacity charge as a Special Connection charge based on planted acres.  Consumption charges or water rates are established periodically by the Board to cover operation and maintenance costs of the District. Stand-by or water availability charges were collected only in the Improvement District "A" until legislation allowed it to be collected District-wide. The first District-wide water availability charge was levied for the fiscal year 1989/90 to help fund a portion of the capital improvement program for additional storage and increased capacity from which all lands within the District would benefit at least to the extent of the charge. The District collects approximately $79,500 annually, which the board has allocated to capital expenditures and debt repayment.   A method of deferring the charge was adopted for property owners who do not have connections to the District and do not intend to make application for water service in the future. 

Debt Service

The $1,300,000 debt service for the 1964 general obligation waterworks bonds was paid off in 1989.

On April 19, 2004, the District entered into an installment sale agreement with Municipal Finance Corporation for $1,500,000 payable to City National Bank. The agreement provided financing for the construction of water storage facilities known as Eastside 3MG tank and Pump Station.  This agreement was refinanced in July of 2013 at an interest rate of 2.35% with a 12-year payback due April 21, 2016.

On August 27, 2007, the District entered into an installment sale agreement with Municipal Finance Corporation for $1,500,000 payable to Citizens Bank. The agreement provided financing for the construction of a water storage tank and pump station in IDA, known as the L.R. Burzell Tank and Pump Station. This agreement was also refinanced in July of 2013 at an interest rate of 2.65% with a 15-year payback due July 15, 2022.

In July of 2013 the District obtained additional financing for the 1.2 million gallon water storage tank (Zone 4 Tank) and the Station 6 pump station for a total of $900,000 at an interest rate of 2.35%.

Yuima Facilities

Yuima takes delivery of treated imported water from Pipelines No. 1 and 2 of the San Diego Aqueduct near Couser Canyon in Valley Center, just north of Lilac Tunnel. The imported water is a blend of Colorado River water and State Water Project water. This treated water used to be disinfected with chlorine only, however sometime within the last 10 years, that changed. It is now chloraminated (treated with chlorine and ammonia) to reduce Trihalomethanes (THM's) which are known carcinogens.   Notices were mailed to customers and adequate newspaper coverage made to advise of hazards involved with kidney dialysis machines and aquariums with this new disinfecting process.   When nitrate levels (which can be adversely affected by chloramination) are too high, MWD reverts to the use of free chlorine.

From the Water Authority’s connection to Yuima, water is delivered through a 20" line to our 0.5 mg tank (Forebay) at the District's main booster plant. Booster pumps, of present capacity of 20 cfs, pump from the Forebay to the two 3 mg (McNally) tanks. A 20" steel line delivers this water to approximately the intersection of San Luis Rey River and Pauma Creek, where it bifurcates into the east and west laterals.

The west lateral terminates in a 12" steel main on Hwy 76 on the West side of the valley at the Schoepe station.

The east lateral terminates on Hwy 76 in a 14" line adjacent to Improvement District "A", near the Tank 8 at the IDA Tap No. 1 Water Service.

Line extensions to these main lines include:

1) Harms Line
2) Hegardt/Roberts Line*
3) Marshall Line
4) Gorowska Line
5) Barrett-Smith/Chapman Line
6) Schaeffer Line
7) Weir Line
8) Oak Tree Line
9) Fairfield Farms Line. *
10) Sam's Mountain Road Line Extension - Phase 1
11) Sam's Mountain Road Line Extension - Phase 2
12) Metta Forest Line
13) Schoepe Line

Other:   1) Line relocation in Club.

Tanks in Yuima include:  

  Capacity (acre-feet)
Forebay Tank    1.50
McNally Tank 1    9.20
McNally Tank 2    9.20
East Side   Tank    9.20
Schoepe Tank     
Total Storage Yuima 29.74

Improvement District "A"

On April 15, 1968 Yuima and Palomar Mutual Water Company entered into an Agreement for Acquisition of Water System and Palomar Mutual became known as Improvement District "A" (IDA). Palomar's water system was transferred together with its rights to develop, produce and divert water which had been given to them by Rossmoyne Village, Inc. The Improvement District operates under a separate operating permit.

In the past there were some special agreements made on a case by case basis, to allow some property owners in IDA to drill wells (e.g. Lindbeck, Chandler, Vorie/Cinquini, Stehly, Huntington and Schmidt). 

Yuima also became successor in interest to the Stipulated Judgment in the case of Strub vs. Palomar.  That judgment limited the Palomar Mutual Water Company's service area (now known as Improvement District A) to the withdrawal of no more than 1,350 acre feet per year from the San Luis Rey River upstream of Cole Grade Road.

The Board sets a separate water rate for IDA to cover IDA’s operating expenses and its equitable share of Yuima's general and administrative expenses. All revenues received from IDA are used solely to pay IDA's expenses for operation, maintenance, and capital improvements.

IDA also includes 1,127 acres of District-owned watershed land and 31 scattered well & reservoir sites (28 operating wells).

Reservoirs include:      

  Capacity (acre-feet)
Tank 8 5.21
Barrett Reservoir (Ag only currently out of service) 2.80
Dunlap Reservoir (Ag only) 5.70
Dunlap Tank 3.68
Perricone Tank 15.35
Hegardt Reservoir (Ag only) 6.00
Tank #1 0.30
Zone 4 Tank                                     3.60
Total Storage IDA 42.64

Private Reservoirs:

  • House/H&H - Operated by owner to benefit their higher elevation lands.
  • Stevens/Underwood/Humason - Operated by owners.
  • Pettis - Operated by owners to benefit their higher elevation lands.
  • Chandler/Dewey/Humason - Operated by owner to store water from his wells which were allowed to be operated under a well lease and catch basin agreement.
  • Huntington/Testa - Operated by owners.

IDA operates a catch basin (Yuima Creek) into Dunlap Reservoir and Pettis Reservoir and water is used through agriculture meters. Also, a second catch (Nate Harrison Canyon) was operated for a number of years into Hegardt Reservoir, but due to overgrowth hampering access, new surface treatment rule, and limited funds and personnel, repairs had not been made. Due to power and water costs rising so rapidly, and the 1987 fire that cleared the area for better access, the District found it feasible to make the necessary repairs to reactivate this catch and maintenance road. In 2017 an agreement was entered into with Humason to refurbish, maintain and operate the catch system for 20 years, thus effectively exercising riparian rights to creek, while separating it from the potable system.


Significantly increased capacity for delivery of imported water can only be achieved through increases in the District's pipeline capacity from the Water Authority. Storage capacity can be increased by either building storage (reservoirs) or by better utilizing the groundwater storage.

Due to the District’s inability to meet peak demands during the summer months, a bond issue was proposed to the voters in the 70’s to parallel the existing 20” mainline so that more imported water could be brought into the District. The measure failed due to non-support from the voting community in the Pauma Valley Country Club (which rarely uses Yuima water unless they experience problems with their own wells). As a result of the failure of this ballot issue, and due to the District’s lack of adequate storage and supply facilities to meet maximum operating demands, the District had no alternative but to declare a moratorium on new connections (Ordinance No. 38-78).

This ordinance was later modified to allow for some domestic connections (Ordinance No. 54-82). The District then turned its attention to meeting demands through the better use of existing wells, new wells, and storage. In late 1989 the District's engineer, submitted a report that suggested some capital improvements that would increase storage and pumping capabilities and that would leave the District in a better position to meet summer peak demands (refer to Engineer dated May 19, 1989, and updated June 16, 1992 "Forecast System Improvements Required to Permit Lifting the Moratorium on Installation of New Services").

Studies are underway for the drilling of additional wells throughout the District, possible further modifications to Strub, and groundwater development not restricted by Strub. The District has entered into private a contract for the purchase of water with Schoepe Enterprises. 

Due to modifications to the operating system (coupled with additional pump, well and pipeline capacity) and voluntary meter down-sizing program, the moratorium was lifted in June 1994 (Ordinance No. 71-94). However, if the current drought continues and restrictions of new local water development are not lifted, a moratorium in the future may be required.

Based upon long-term demand forecasts for agricultural and urban development within the current boundaries of the District, coupled with a number of annexation requests expected to be driven by local water shortages affecting both agriculture and new housing in adjacent under-served areas, the District has determined that a new transmission pipeline will eventually be required to bring additional imported water into the District from the First and Second San Diego Aqueduct Pipelines.

Two potential routes are under consideration. The first (“Southern Route”) would parallel the District’s existing 20” pipeline and would be built at the sole expense of the District. The second (“Northern Route”) could be a joint venture between the San Luis Rey Indian Water Authority and the District and would connect to the Metropolitan Water District portion of the aqueduct at a point just north of the jurisdictional boundary with the San Diego County Water Authority.

No definitive timetable for the construction of either a Southern or Northern Route pipeline has yet been established. That decision will largely hinge on the availability of low-cost financing, the realization of additional demand, and a timely re-assessment of long-term prospect for the availability of imported water from the State Water Project and the Colorado River system.


During the early to mid 1970's many water agencies in California were having difficulty finding suitable liability insurance coverage at an affordable price. These agencies asked the Association of California Water Agencies Joint Powers Insurance Authority (ACWA/JPIA) to explore the feasibility of developing a liability insurance program, specifically for water agencies, which would address the issues of suitability and affordability. After many months of research by outside consultants, ACWA/JPIA was formed to provide liability coverage tailored to the needs of California water agencies.

The basic auto and general liability coverage had several layers, i.e. (1) a self-insured layer, (2) a layer pooled among participating water districts, and (3) a layer of group purchased commercial excess insurance. Because risk sharing among water agencies was so successful in its first few years, a Property Program was added in January of 1983 and a Workers' Compensation Program in July of 1984. Yuima participates in all three of these JPIA Programs. 

Since the early 60’s the Employee Health Insurance Coverage was administered by the ACWA Health Plan Insurance Trust (HPIA).   In the 90’s the HPIA was changed to ACWA Services Corporation (ACWA ASC), which later changed to ACWA Health Benefits Authority (ACWA HBA) to comply with ERISA issues. On July 1, 2012 the ACWA Health Benefits Authority (HBA) transitioned its operations and health benefits programs over to the ACWA/Joint Powers Insurance Authority (ACWA/JPIA). HBA dissolved and all of the assets and liabilities were transferred to ACWA/JPIA. Many of the desired goals for future services and long-term savings were already being developed at ACWA/JPIA and, as such, can now be implemented simultaneously. Yuima also participates in the ACWA/JPIA employee health benefit programs.


[1] San Diego County Water Authority Comprehensive Annual Financial Report Fiscal Year Ended June 30, 2008, 81.

[2] Metropolitan Water District Website http://www.mwdh20.com/mwdh20/pages/memberag/agencies/sandiego.htm

* Do not have records of construction or acceptance by District, however, meters have been placed on these lines.