Upper Santa Ana Valley – Yucaipa
Statistics
- Basin Name
- Upper Santa Ana Valley – Yucaipa
- Basin Number
- 8-002.07
- SGMA Basin Priority
- High
- Critically Overdrafted
- No
- Hydrologic Region Name
- Southern California
- Counties
- San Bernardino
At-A-Glance
Located in California’s South Coast hydrologic region, the Upper Santa Ana Valley – Yucaipa is 22,219 acres in size. This High priority basin is home to an estimated 56,527 people (2010 value), which have been at a rate of 32.67.
Upper Santa Ana Valley – Yucaipa is a(n) basin with approximately 246 wells, of which approximately 37 are water supply wells. Groundwater accounts for approximately 74.98 percent of the basin’s water supply.

Basin Notes
2003: Bulletin 118 basin description
2014: CASGEM prioritization – medium. Comments: Overdraft. Documented impacts of nitrates and sulfates. (B‐118)
2016: basin boundary modification with Bunker Hill 8-002.06, Rialto-Colton 8-002.04, and Riverside-Arlington 8-002.03
Revised basin boundary description
Jurisdictional boundary modification request by Yucaipa Valley Water District incomplete.
2018: Draft basin priority – high. Comments. 1) CASGEM/WDL/GWIDS: Longterm hydrographs show groundwater level decline. Source: DWR 2) See Final Phase 1 Report Common Ground Memorandum, San Timoteo Watershed Management Program,San Timoteo Watershed Management Authority / Wildermuth Environmental, Inc., 2002
2018 Final Basin Prioritization: Basin prioritization is changed from medium to high priority.