Water Well Drilling Contractors in California

Geology & Depth

California's Central Valley sits atop one of the world's most productive aquifer systems with thick sequences of alluvial fan deposits, while coastal areas have smaller, fractured bedrock aquifers. Sierra Nevada foothills require drilling through granite and metamorphic rock.

Most residential wells in California are drilled to 350 feet, with a typical range of 100–800 feet. Water table depth: 50-300 feet in the Central Valley (declining in some basins due to overdraft); 100-600 feet in Southern California.

Permits & Licensing

California requires a C-57 Water Well Drilling Contractor license from the Contractors State License Board. Homeowner drilling is effectively prohibited due to licensing and environmental requirements.

Permit authority: County Environmental Health Departments issue permits; the State Water Resources Control Board oversees Sustainable Groundwater Management Act (SGMA) compliance. Expect $300-$2,000 (varies dramatically by county) in permit fees.

Primary Aquifer

Central Valley Aquifer System / Coastal Basin Aquifers. About 10% of California households use private wells, but the Central Valley has some of the highest concentrations of domestic well users in the nation.

Best drilling months: Year-round in most areas; some mountain regions limited by snow access from November through March.

Common Water Quality Concerns

California well water commonly contains: arsenic, nitrate, hexavalent chromium, 1,2,3-TCP, total dissolved solids, uranium. A comprehensive water test after drilling (typically $150–$500) will identify which treatments, if any, your well needs.