San Joaquin Valley Deep Fossil Aquifer — Tulare Basin
Deep confined aquifer beneath California's San Joaquin Valley. The Tulare Basin contains fossil water below the Corcoran Clay confining layer — a regional aquitard that separates modern recharge from ancient water. Massive land subsidence (up to 28 feet) has occurred from extraction.
Overview
Deep confined aquifer beneath California's San Joaquin Valley. The Tulare Basin contains fossil water below the Corcoran Clay confining layer — a regional aquitard that separates modern recharge from ancient water. Massive land subsidence (up to 28 feet) has occurred from extraction.
Additional Notes
California DWR SGMA critically overdrafted basin. Among the worst groundwater subsidence zones in the world.
Water Source Data
Water Intelligence Score Breakdown
Total: 76/100Risk Assessment
Source depletion probability
Rights & regulatory exposure
Contamination & ecosystem risk
Geological Intelligence
Formation & aquifer contextHigh porosity — shallow, rechargeable aquifer
Ancient water, no modern recharge — non-renewable on human timescales
Land Details
PrivateWater Rights
UnverifiedGroundwater Rights
Subsurface water extraction
Rules vary significantly by state — from absolute ownership (landowner controls all water below) to correlative rights (shared among overlying owners) to regulated permit systems.
- Doctrine varies by state jurisdiction
- May require state-issued permit
- Subject to aquifer-wide management plans
- Pumping rates often capped
Disclaimer: Water rights information is provided for research and informational purposes only and does not constitute legal advice. Rights status, seniority, transferability, and enforceability vary by jurisdiction and change over time. Always consult a licensed water rights attorney and verify status with the relevant state water resources agency before any acquisition or use decision.
Read full disclaimerRegulatory & News Alerts
Location
Data Sources & Attribution
Updated Apr 5, 2026Data is sourced from public and authoritative providers. Hi3 Water aggregates, normalizes, and scores records but does not assert ownership of underlying source data. Always verify critical details with the primary source before any decision.