Stanislaus and Tuolumne Rivers Groundwater Basin Association Groundwater Sustainability Agency

The STRGBA GSA was formed to coordinate groundwater management activities and to comply with SGMA.  The STRGBA GSA became the exclusive GSA for the Modesto Subbasin on 5/29/2017.

Prior to forming a GSA the STRGBA members worked cooperatively to provide coordinated planning to make the best use of available water resources of the Modesto Subbasin in order to meet the needs of the agencies, and meet the purposes of the Association.

The purposes of the Association were:

  • To determine and evaluate the subbasin’s groundwater supply.
  • To promote coordination of groundwater management planning activities, including the preparation of the groundwater management plan.
  • To develop a hydrologic groundwater model of the groundwater basin.
  • To determine the subbasin's need for additional or improved water extraction, storage, delivery, conservation, and recharge facilities.
  • To provide information and guidance for the management, preservation, protection, and enhancement of groundwater quality and quantity in the subbasin.

The STRGBA was awarded a Local Groundwater Assistance (LGA) Grant to conduct the Groundwater Characterization and Aquifer Recharge Study. LGA Grants provide local public agencies with up to $250,000 to conduct groundwater studies or carry out groundwater monitoring and management activities. The projects funded by the grant are for groundwater data collection, modeling, monitoring and management studies; monitoring programs and installation of equipment; basin management; development of information systems; and other groundwater related work.

Should you have any questions regarding the Groundwater Recharge and Aquifer Characterization Study, or need any further information, please feel free to contact John Davids (Chairman) at 209-526-7564, or Michael Riddell (Vice-chairman) at 209-869-7128.


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