Wholesaler Water Supply Information

The Municipal Water District of Orange County (MWDOC) aims to deliver a variety of services that provide benefit to its stakeholders and constituents. Our efforts focus on sound planning and appropriate investments in water supply development, water use efficiency, public information, legislative advocacy, water education, and emergency preparedness.

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State Water Resource Control Board
Emergency Regulations

On May 9, 2016, Governor Brown issued Executive Order B-37-16 “Making Water Conservation a Way of Life” that extends the Emergency Regulation to January 31, 2017. In response to this Executive Order, on May 18 the State Water Resources Control Board (State Board) adopted a localized self-certification approach that replaces the prior state imposed mandatory conservation standard, which ranged from 8% to 36% for each retail agency. This new approach mandates each retail agency to conduct a “stress test,” certifying whether they have sufficient available potable supplies for a three-year period under high demand and low precipitation conditions to meet the needs of their customers. As part of this self-certification process, the State Board emergency regulations requires urban water wholesale agencies (i.e. Metropolitan Water District of Southern California and MWDOC) to publicly disclose the amount of regional water supplies they expect to deliver to retail water suppliers for each year over the three-year period. This posting provides the required wholesale information from MWDOC for our 28 member agencies.

Robert Hunter General Manager, MWDOC

“While water supplies have improved over the last year and we can meet our service area’s imported demands over the next three years, we do not know what the next winter will bring. We need to be cautious in our water use and continue to be efficient.”

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Wholesale Water Supply Requirements

MWDOC is a third-largest member agency of the Metropolitan Water District of Southern California (Metropolitan) and the largest purchaser of treated drinking water. MWDOC provides and manages imported water supplies used in Orange County, with the exception of the cities of Anaheim, Fullerton, and Santa Ana. As the wholesale agency for 28 cities and water agencies within Orange County, MWDOC is required by the State Board to assist our retail agencies meet the State Board’s self-certification process by providing data and information on the imported water supplies that we project to deliver to them.

To determine MWDOC’s expected imported supply need over the next three years, MWDOC coordinated with each retail agency in assessing their local and imported supply needs for the stress test period. These estimates were prepared in coordination with both our retail member agencies (e.g. urban water suppliers) and Metropolitan. Additional wholesale information required by many of our member agencies for the groundwater supply is being provided by Orange County Water District (OCWD).

Below is a summary of the total imported supplies requested by MWDOC’s 28 member agencies over the next three years as part of this process:

Total Imported Water Supplies

MWDOC’s imported supply request2017
(2013 hydrology)
(2014 hydrology)
(2015 hydrology)
Total Retail Agency177, 130 AF177, 130 AF177, 130 AF
Groundwater Recharge49, 750 AF49, 750 AF49, 750 AF
MWDOC Imported Supplies - TOTAL226, 880 AF226, 880 AF226, 880 AF

MWDOC’s Imported Water Supply Request was revised on June 21, 2016 due to changes in retail agency supply requests.

The “groundwater recharge” represents Orange County Water District’s request for imported water supplies to recharge/replenish its groundwater basin to manage its expected groundwater production over the next three years.

The stress test emergency regulation requires that the wholesaler information identify each source of water and the amount of water expected to be delivered to each of the urban potable water retailers for the water years 2017, 2018 and 2019. The required assumptions include using:

  • The same hydrologic conditions of Water Year (WY) 2013 occur in WY 2017
  • The same hydrologic conditions of WY 2014 occur in WY 2018
  • The same hydrologic conditions of WY 2015 occur in WY 2019

Source of Imported Water Supplies

MWDOC purchases imported supplies and groundwater recharge for our retail agencies exclusively from Metropolitan. Metropolitan utilizes its supplies to meet its 26 member agencies’ imported water needs from three key sources: State Water Project, Colorado River Aqueduct, and storage. Below is a brief description of these sources and assumptions used to demonstrate their availability of supplies.

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State Water Project Supplies

Metropolitan assumes receiving the same State Water Project (SWP) “Table A” supplies as the hydrologic conditions of water years 2013, 2014, and 2015 for the next three years. Providing a SWP Allocation of 35% for 2017, 5% for 2018, and 20% for 2019.

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Colorado River Aqueduct Supplies

Metropolitan assumes receiving a Colorado River Aqueduct Base Supply similar to the hydrologic conditions of water years 2013, 2014, and 2015 over the next three years. This provides Metropolitan with its Colorado River basic apportionment, Imperial Irrigation District’s Conservation Program, Palo Verde Irrigation District’s land management program and San Luis Rey’s Canal Lining supply project, as well as its transfer obligation to Coachella Valley Water District.

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Metropolitan Storage Supplies

Due to the limited supplies under the Water Years of 2013, 2014, and 2015. Metropolitan utilized its water storage supplies to meet projected imported demands over the three-year period. Metropolitan will start 2017 with over 2.12 million acre feet (AF) in total storage and expect to end with roughly 657,000 AF at the end of 2019. Metropolitan has a diverse water storage portfolio ranging from groundwater storage in the Central Valley of California to surface storage along the Colorado River in Lake Mead (Intentionally Created Surplus – ICS). For further details on Metropolitan’s sources of supplies and its supply-estimation methodology.

Learn More

MWDOC Imported Supply Projections

MWDOC projections for Member Agency imported water supply for the three projected years:

MWDOC member agency
Imported water suplies
(2013 hydrology)
(2014 hydrology)
(2015 hydrology)
City of Brea3, 382 AF3, 382 AF3, 382 AF
City of Buena Park4. 488 AF4. 488 AF4. 488 AF
East Orange Country Water District - Retail Zone310 AF310 AF310 AF
East Orange Country Water District - Wholesale Zone3,819 AF3,819 AF3,819 AF
El Toro Water District9,495 AF9,495 AF9,495 AF
City of Fountain Valley3, 028 AF3, 028 AF3, 028 AF
City of Garden Grove7, 772 AF7, 772 AF7, 772 AF
Golden State Water Company6,217 AF6,217 AF6,217 AF
City of Huntington Beach9,092 AF9,092 AF9,092 AF
Irvine Ranch Water District15,529 AF15,529 AF15,529 AF
Laguna Beach County Water District1,813 AF1,813 AF1,813 AF
City of La Habra500 AF500 AF500 AF
City of La Palma642 AF642 AF642 AF
Mesa Water District0 AF0 AF0 AF
Moulton Niguel Water District28,771 AF28,771 AF28,771 AF
City of Newport Beach4,968 AF4,968 AF4,968 AF
City of Orange9,379 AF9,379 AF9,379 AF
Orange County Water District49,750 AF49,750 AF49,750 AF
City of San Clemente9,532 AF9,532 AF9,532 AF
City of San Juan Capistrano6,910 AF6,910 AF6,910 AF
Santa Margarita Water District28,726 AF28,726 AF28,726 AF
City of Seal Beach1,138 AF1,138 AF1,138 AF
Serrano Water District489 AF489 AF489 AF
South Coast Water District6,659 AF6,659 AF6,659 AF
Trabuco Canyon Water District3,081 AF3,081 AF3,081 AF
City of Westminster3,720 AF3,720 AF3,720 AF
Yorba Linda Water District7,672 AF7,672 AF7,672 AF
MWDOC Total:226,880 AF226,880 AF226,880 AF

[1] MWDOC’s Member Agency Imported Water Supply projections were revised in June 21, 2016 due to changes in retail agency supply requests.
[2] East Orange County Water District is both a retailer and a wholesaler. The wholesale imported water to portions of the City of Orange, portions of Golden State Water Company – Cowan Heights, portions of Irvine Ranch Water District – Orange Park Acres, and the entire service are of the City of Tustin’s Water Department.

image of Colorado river aqueduct map

Although MWDOC can meet the imported needs of its member agencies, the need to conserve remains. Southern California is still in a drought. Local precipitation has reach its fifth consecutive year below average; and local groundwater as well as local surface water reservoirs are still at historic lows.

Based on these conditions, the MWDOC Board on June 15, 2016 adopted a resolution declaring a “Condition 2 – Water Supply Alert”, as part of MWDOC’s Water Shortage Contingency Plan, which calls for the continued implementation of extraordinary conservation measures during the emergency regulations and encourages retail water agencies to amend their water drought ordinances to incorporate the Governor’s new permanent conservation measures.

Furthermore, to continue the significant water savings achieved by Orange County over the past 12 months, and to be cautious for the upcoming water year, the MWDOC Board also called for a countywide water saving goal of approximately 10% from the average annual demands of calendar years 2013 and 2014.

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