County approves extension for Coulterville drought‑relief project; testing to check well impacts on neighbors

Mariposa County supervisors approved on Aug. 19 a first amendment to the county’s agreement with Yosemite Falls Inc. for the Coulterville drought relief project, extending the contract to June 30, 2026 and continuing work funded by a $2.3 million Department of Water Resources grant.

Officials said the project will drill a new production well, rehabilitate an existing well and an older storage tank, and add generator backup. County representatives said Yosemite Falls has drilled two test wells so far; one did not produce and the second was a “quite a producer.” Two monitoring wells have been installed and staff said they will conduct a 10‑day pumping test on the producing well in September or October during the driest season to assess effects on the aquifer and nearby properties.

Supervisor Poe asked whether nearby property owners had been contacted. County staff said right‑of‑entry was obtained and the county has been in communication with the Bradshaw family, whose property is adjacent to the test site. Staff said they would share results of monitoring with the adjacent property owners after data collection and invited further offline conversations about road wear caused by project equipment.

Supervisor Kaiser thanked staff and Yosemite Falls for their work; board members described the project as important for Coulterville’s water reliability. The contract amendment was included on the consent agenda approved earlier in the meeting.

County staff emphasized monitoring and reporting commitments and said the 10‑day test will generate a monitoring report to inform next steps.