Before the formation of West Basin Municipal Water District, coastal Los Angeles leaders and community members found there was a need for a public entity dedicated to managing and protecting local water supplies. As a result, West Basin was formed in 1947 with the task of making local water supplies more reliable by seeking new water sources and protecting groundwater supplies through reduced pumping. Since then, the District has been delivering on its mission of water reliability and establishing drought resiliency through balanced and cost-effective water supply diversification.

This year, West Basin celebrates more than seven decades of water reliability. Throughout 2022, the District will commemorate key moments in its history in recognition of this major milestone. To learn more visit:

West Basin 75th Anniversary


Early Years
1850’s – 1950’s Formation and the Early Days
1854 First water wells drilled in the West Basin.
1918 Salt water intrudes into coastal aquifers in Redondo Beach area.
1922 Groundwater drops below sea level, salt water intrudes into drinking water wells in El Segundo.
1931 Following approval of a $220 million dollar bond, Colorado River Aqueduct construction begins.
1940’s Industry increases pumping for war.
1940 Redondo Beach High School – salt water contaminates groundwater well.
1940’s Planning for State Water Project begins.
1941 Colorado River Aqueduct is complete.
1942-1944 West Basin Survey Committee formed to determine salt water damage to the groundwater supply.
1944-1945 Production is 69,476 acre feet a year.
1945 West Basin Groundwater Conservation Group (WBGCG) formed by representatives from cities, private water utilities and local industries.
1945 WBGCG releases report showing more water being withdrawn from groundwater basin than being naturally replenished and overdraft is 29,000 acre feet. Suggested corrective measures include reduce the overdraft of groundwater, educating the public about the water shortage problem and finding a source of supplemental water, including reclaiming water from the San Fernando Valley and the Owens Valley.
1946 Legal action taken to arbitrate water rights and control overdraft in California Water Service Company, et al. v. Compton, et al., L.A. County Superior Court, Case # 506,806.
1946 West Basin Water Association organizes and initiates study under Harold Conkling to determine supplemental water source needed to prevent overdraft of groundwater supplies. Conkling’s report recommends the use of Colorado River water as supplemental supply. West Basin needs majority of public to vote in support of its formation as a Municipal Water District and become member of Metropolitan Water District of Southern California (MWD).
1947 Mayors of five South Bay cities form the South Bay Water Committee.

  • Jan – First attempt to form West Basin Municipal Water District fails.
  • Nov – Second attempt to form West Basin Municipal Water District succeeds by an 8:1 margin.
1948 U.S. Geological Survey releases water supply report showing fresh groundwater is threatened by salt water intrusion.

  • West Basin becomes member of Metropolitan Water District of Southern California.
  • Following formation of West Basin, a five-member Board of Directors is elected and sworn into office. First board includes Robert E. Austin, William C. Farquhar, Russell T. Hutchins, Ralph W. Pritchard, and August H. Riess.
  • Kenneth K. Wright is appointed Attorney of the District.
  • Carl Fossette is appointed General Manager of the District.
1949 Report on reclamation is prepared for L.A. County Board of Supervisors, outlining opportunities for using reclaimed water.

  • First supply of imported water used in West Basin service area.
1950 In an effort to control salt water intrusion and determine effectiveness of maintaining a fresh water pressure ridge along the coast, County Flood Control begins fresh water injection tests into abandoned water well in Manhattan Beach.

  • $750,000 grant allocated by California State Legislature to start injection well testing.
1951 Legislature amends the County Flood Control District Act to authorize establishment of conservation zones.

  • Salt water intrusion increases in the West Basin.
1952 Report of Referee in West Basin adjudication is filed with the Court, ordering water producers to reduce groundwater extractions, requiring purchase of supplemental water to offset reduced pumping.

  • Major aqueduct expansion required due to tremendous growth of Southern California following World War II.
1953 Test barrier, paralleling Manhattan/Hermosa Beach area, development begins.

  • Ralph B. Helm appointed Attorney for the District.
1954 Zone II is established to carry on barrier testing started by the State.
1955 Forty-six major groundwater producers in the West Basin voluntarily agree to restrain their groundwater extractions to 56,963 acre feet per year.

  • California State Legislature adopts the Water Replenishment District Act and the Recordation of groundwater Production Act.
1956 Second adjudication action filed to gain jurisdiction over new producers and those who may have been overlooked during the service of the original action. Court orders continuation of the West Basin Reference to update physical facts and directs State Water Rights Board to make these determinations.
1958 Second report was prepared for the County Board of Supervisors, affirming findings of first report from 1949. It proposes construction and operation of water reclamation plant at Whittier Narrows to demonstrate the feasibility of wastewater reclamation.
1959 Central and West Basin Water Replenishment District is formed to purchase supplemental water to replenish the depleted groundwater basins.
1959 Construction begins on State Water Project.
1960’s – 1970’s Protecting Groundwater
1960 Draft of Continued Reference Report on West Basin Adjudication is filed with the Superior Court and recommends limiting groundwater production, providing exchange for water pool, appointing a Watermaster to administer the terms and conditions of the Court, and continued jurisdiction by the Court over this Action.
1961 Aqeduct expansion complete, bringing imported water delivery capacity to 1,180,000 acre-feet annually. Court enters judgment in the original West Basin adjucation requiring groundwater production to be reduced to 64,042 acre feet.
1963 Development of test barrier paralleling the coast of Manhattan/Hermosa Beach is complete.
1966 Court enters second judgment against additional West Basin pumpers overlooked in first Action. All were made party to the terms of the original Judgment and the annual pumping was adjusted to 64,468 acre feet. Work begins on the Dominguez Gap Barrier Project to protect lower fresh water aquifers in the southeast area of the West Coast Basin from salt water intrusion.
1968 Flood Control District completes West Coast Basin Seawater Barrier consisting of 94 recharge wells injecting 50 million gallons of fresh water daily and 256 observation wells protecting groundwater supplies from salt water intrusion.

  • City of Los Angeles Department of Water and Power constructs activated carbon gravity flow pilot test plant at Hyperion Sewage treatment plant to determine whether water from Hyperion could be reclaimed.
1971 Dominguez Gap Barrier Project begins, consisting of 29 injection wells.
1972 Special water conservation area operated by the County Flood Control District for West Coast Basin ends. Entire cost of financing barrier injection programs hereafter must be supported by the water pumpers.

  • West Basin Municipal Water District asks water users to help and asks Water Replenishment District to get court approval to permit increased pumping, temporarily.
  • Court grants Ex Parte order to permit additional over-extractions to the West Coast Basin beyond the 10% allowed in the judgment.
  • To maintain emergency storage at Metropolitan’s Lake Matthews, West Basin Municipal Water District informs Metropolitan that pumpers have agreed to pump more water and use less imported water.
  • West Basin receives delivery from State Water Project through the Jensen Treatment Plant. State Water Project replaces Colorado River water as main source of supplemental water in West Basin.
1973 To prevent salt water intrusion at the southern end the County Flood Control District, additional facilities are recommended for West Coast Seawater Basin Barrier Project.

  • In response to new requirements of the State Health Department, West Basin Water Association submits a basin-wide plan to monitor quality of well water supplies pumped for domestic use.
1974 Metropolitan Water District commences delivery of State Water Project in lieu of the Colorado River to West Basin for injection into seawater barriers.

  • Water Replenishment District terminates participation in the proposed County Water Recycling Project at Playa de Rey.
  • Hyperion project is terminated due to cost of material and labor.
1975 Eleven new injection wells complete in West Coast Basin Seawater Barrier Project, bringing total number of injection wells to 105.
1976 In FY 1975-76, West Basin Municipal Water District purchases 168,555 acre feet of water from Metropolitan Water District.

  • Metropolitan Water District suspends the delivery of water for spreading grounds due to severe drought in Northern and Central California to aid drought-stricken farmers rather than for Southern California water replenishment.
Drought cms
1980’s – 1990’s Drought and Local Supply
1987-1992 California experiences one of its most serious droughts in history.
1988 Congress enacts Federal Disaster Assistance Act of 1988, due to extent and severity of drought.

  • Water shortages occur in 45 California counties.
1989 10 million people under drought-induced water rationing or conservations programs.
1990 – 1996 Rich Atwater joins West and Central Basins as General Manager.
1991 West Basin and City of Los Angeles reach agreement to deliver treated sewer water from the City’s Hyperion plant to a new West Basin Water Recycling Facility in El Segundo.
1994 West Basin/Hyperion Pump Station is built to pump water to facility.
1995 West Basin Water Recycling Facility construction complete, delivering water to first customer, El Segundo Lakes golf course.

  • West Basin Water Recycling Facility begins injecting water into the seawater barrier to protect the groundwater supply from salt water intrusion.
  • West Basin brings four recycling facilities online: West Basin Water Recycling Facility, Chevron Nitrification Plant, West Coast Basin Barrier Project, and Exxon/Mobil Nitrification Plant.
1996 West Basin Water Recycling Facility visitor’s center is complete.

  • Phase I Water Recycling Facility begins operating at full capacity, producing 15 million gallons a day.
  • Phase II Water Recycling Facility construction begins.
1997 Phase II Water Recycling Facility complete, expanding production capacity of tertiary and barrier water.
1998 West Basin hosts first Water Harvest festival at the Water Recycling Facility. Hollywood Park in Inglewood is 100th recycled water customer.
1999 West Basin increases percentage of near-distilled quality sewer water injected into the seawater barrier from 25 to 50 percent.

  • West Basin completes construction of Juanita Millender-McDonald Water Recycling Facility in Carson, the first on-site, ultra-pure sewer water purification plant in the nation.
Pie Chart
2000 – Present Diversification of Supply
2000 Phase III of the Water Recycling Facility expands capacity of microfiltration and reverse osmosis.
2004 Department of Water Resources awards West Basin $9 million Proposition 13 grant for expansion of its water recycling facilities.

  • Construction begins on Phase IV Expansion of Water Recycling Facility.
​2005 West Basin’s Water Recycling Facility (WBMWRF) celebrates 10th anniversary and the following achievements:

  • phases of construction make the WBWRF the largest facility of its type in the nation;
  • WBWRF is the only water purification facility in the world to produce 5 types of designer waters;
  • 8 billion gallons of water produced annually;
  • 68 miles of pipeline in the future Harbor/South Bay Water Recycling Project;
  • 79 miles of existing recycled water pipeline;
  • 206 recycled water users; and
  • 25,000 children participated in the Plant Protector Water Exploration tours
2006 West Basin adopts Conservation Master Plan as a guide for regional investments and translates conservation goals into tangible initiatives for residents, businesses and various levels of government.

  • West Basin and Central Basin become separate entities.
2007 Construction complete on Phase IV Expansion, increasing recycled water production by 15 million gallons a day.
2008 West Basin produces its 100 billionth gallon of recycled water.
2010 West Basin reaches 350 recycled water customer connections, and dedicates its demonstration ocean-water desalination facility and water education center in Redondo Beach.
2018 West Basin produces its 200 billionth gallon of recycled water.
2019 West Basin Director Gloria D. Gray begins serving two-year term as chairwoman of the Metropolitan Water District of Southern California’s Board of Directors.
Print Friendly, PDF & Email