The Santa Clarita Valley Water Agency (SCV Water) is a member of the Santa Clarita Valley Groundwater Sustainability Agency (SCV-GSA). The SCV-GSA was formed via a Memorandum of Understanding (MOU) on May 24, 2017. The MOU contemplates its members creating a Joint Powers Authority (JPA) governance structure. SCV-GSA member agency staff have negotiated a Joint Powers Agreement (JPA Agreement) and an Administrative Services Agreement whereby SCV Water would provide administrative, management, and technical services necessary to assure compliance with the Sustainable Groundwater Management Act including preparation of a Groundwater Sustainability Plan.

On May 24, 2017, the SCV-GSA was formed via execution of an MOU between six local entities. The members listed in the MOU are Castaic Lake Water Agency, City of Santa Clarita, County of Los Angeles, Los Angeles County Waterworks District No. 36, Newhall County Water District and the Santa Clarita Water Division. Three of these member agencies are now part of SCV Water, the successor agency as defined by Senate Bill 634. The MOU describes: coordination, responsibilities, funding, consideration of interests of all beneficial uses and users of groundwater, and other items. With limited time to create the SCV-GSA among six member agencies, an MOU was the logical approach to form the SCV-GSA. Members understood operating the SCV-GSA under an MOU would be inefficient, and articulated a desire to form a JPA at a later time.

The SCV-GSA was formed pursuant to the Sustainable Groundwater Management Act to be the Groundwater Sustainability Agency (GSA) for the Santa Clara River Valley East Subbasin, groundwater basin number 4-4.07 ("Basin"), per the State of California, Department of Water Resources (DWR) Groundwater Bulletin 118.

On September 16, 2014, Governor Jerry Brown signed into law Senate Bills 1168 and 1319, and Assembly Bill 1739, collectively known as the Sustainable Groundwater Management Act (SGMA), codified in Part 2.74 of Division 6 of the California Water Code, commencing with Section 10720.

SGMA became effective on January 1, 2015, and various clarifying amendments to SGMA, including Senate Bills 13 and 226 and Assembly Bills 617 and 939, were signed in 2015 and became effective on January 1, 2016.

The legislative intent of SGMA is to provide sustainable management of California's groundwater basins, to enhance local management of groundwater, to establish minimum standards for sustainable groundwater management, and to provide local agencies with the authority and the technical and financial assistance necessary to sustainably manage groundwater.

The Members are all local public agencies with water supply, water management, and/or land use responsibilities in at least some portion of the Basin and as a result, each has the statutory authority to participate in GSAs for the Basin.