Gilroy-Hollister Valley – Llagas Area



Located in California’s Central Coast hydrologic region, the Gilroy-Hollister Valley – Llagas Area is 47,371 acres in size. This High priority basin is home to an estimated 88,905 people (2010 value), which have been at a rate of 11.35.

Gilroy-Hollister Valley – Llagas Area is a(n) basin with approximately 2196 wells, of which approximately 96 are water supply wells. Groundwater accounts for approximately 40.22 percent of the basin’s water supply.

Source: CA DWR
Source: CA DWR

Basin Notes

2003: Bulletin 118 basin description

2016: Basin boundary modification approved

Revised basin boundary description

2018: Basin prioritization groundwater level comment – [Santa Clara Valley Water District ]Annual Report shows stable longterm hydrographs for the most part. Source:

2018 Final Basin Prioritization: Basin status remains unchanged at high priority.

GSA Information