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A History of the Raymond Groundwater Basin at a Glance:


First wells drilled in Raymond Basin to supply water for irrigated agriculture and expanding municipalities.

On September 23, 1937, Pasadena initiated proceedings in Superior Court against Alhambra and other major Raymond Basin water users. The action sought to adjudicate and gain quiet title to Pasadena’s rights in the basin, and to enjoin the annual overdraft. The trial court required Pasadena to amend its complaint to name as defendants all entities in the basin pumping more than

100 acre feet annually. There were 30 defendants in all. The judge also ruled that the suit was not a simple action to quiet title but was a general adjudication of water rights in the basin. The first basinwide adjudication of groundwater rights in California.


Referee’s report filed in Raymond Basin litigation; this draft report described the basic geology of the Raymond Basin and specified the location of the Monk Hill Basin, and the Pasadena and Santa Anita subareas. The draft report stated the safe yield for Raymond Basin as a whole was 21,900 acre feet per year and recommended limiting withdrawals to the safe yield and using imported water to meet further demands.


Judge Collier signed the judgment on December 23, 1944, adopting the stipulation worked out by the parties. 


The DWR Report of Referee filed October 5, 1954 increased the estimated safe yield to a total of 30,622 acre feet. The Court issued a Modification of Judgment on April 29, 1955, increasing the decreed rights of the parties proportionally to a total of 30,622 acre feet, effective July 1, 1955.


On January 17, 1974, the second modification of Raymond Basin Judgment was signed allowing parties with previously established, State-issued, diversion licenses partial credit for spreading of canyon diversions in spreading grounds in the vicinity of the Arroyo Seco, Eaton Wash, and Santa Anita Creek Canyon. This amendment provides flexibility in-lieu of taking full, direct, diversions from these streams.


On March 26, 1984, the third modification of Raymond Basin Judgment was approved, reconstituting the basin governance system by assigning watermaster responsibilities to Raymond Basin Management Board, successor to the Raymond Basin Advisory Board. The Board’s authority to manage stored water in the basin ushered in the era of conjunctive use and provided the mechanism for local management of the groundwater resource while retaining the safe yield concept of the original adjudication.


On August 10, 2002, the Board approved the Lead Agency Agreement for the Raymond Basin/MWD Conjunctive Use Program.


In July of 2004 the Board of Directors vote to accept a proposal by the Main San Gabriel Basin Watermaster to provide administrative support.  The Raymond Basin Management Board’s offices officially move to Azusa, CA.

Raymond Basin along with other water agencies and municipalities collaborate to develop water supply enhancement projects which are packaged together and called the Southern California Foothill Communities Water Supply Reliability Program (WSRP).


Draft Supplemental Water Quality Criteria for Raymond Basin was published in March and distributed to all parties to the judgment.


Raymond Basin Management Board and Main San Gabriel Basin Watermaster formed the Foothill Water Coalition, whose primary focus is to cooperatively seek Federal and State funding for regional water supply reliability projects. Monk Hill Task Force is formed to review and resolve issues unique to the Monk Hill producers and their region.



The Board adopted revisions to the Rules and regulations pertaining to annual report distribution consistent with the Judgment. 


The Board approved Cooperative Agreement for the Santa Anita Stormwater Flood Management and Seismic Strengthening Project. This project involves improvements to Santa Anita Dam and existing facilities to better capture stormwater and maximize conservation for the Eastern Raymond Basin.



The Board submitted a draft Salt and Nutrient Management Plan to the Los Angeles Regional Water Quality Control Board.


September 2014, Governor Jerry Brown enacted the Sustainable Groundwater Management Act (SGMA). The act is intended to promote groundwater extraction accountability and stability. The Raymond Basin was named in SGMA as an adjudicated basin and was required to comply with certain reporting requirements by April 2016.


January 2015, the Board approved New Well Construction and Destruction Guidelines. These guidelines are not only a tool to be used in tracking wells, but will also provide a technical basis for better management of groundwater extractions and contamination control.


April 2015, the Board established a Short-Term Storage Program for the Pasadena Subarea. This provides some fliexibility for Producers to store water during wet years for use in the subsequent year.



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