Recent Studies
Areas listed below have been studied recently by the GAMA program.
Groundwater resources used for domestic supply studies are in green.
Groundwater resources used for public supply studies are in blue.
Western Central Valley
- Western Central Valley
- Dates Sampled: April - July 2023
- Depths Sampled: 70 - 520 feet
- Data:
- Publication:
- Multiple. See the Studies by Location page for more information.
- Dates Sampled:
- Depths Sampled:
- Data:
- Publication:
Gilroy-Hollister Basin & Surrounding Areas
- Gilroy Hollister basin and surrounding areas
- Dates Sampled: August – October 2022
- Depths Sampled: 157 - 800 feet
- Data: USGS Data Release
- Publication:
- Gilroy-Hollister Basin
- Dates Sampled: August 2008
- Depths Sampled: 339 - 700 feet
- Data: USGS Data Series 463
- Publication: USGS SIR 2014-5023
Kern County
- Kern County
- Dates Sampled: January - April 2022
- Depths Sampled: 200 - 870 feet
- Data: USGS Data Report
- Publication:
- Kern County Sub-Basin
- Dates Sampled: January - March 2006
- Depths Sampled: 400 - 1,400 feet
- Data: USGS Data Series 337
- Publication: USGS SIR 2011-5218
Eastern Sacramento Valley and Foothills
- Eastern Sacramento Valley and Foothills
- Dates Sampled: July - November 2021
- Depths Sampled: 71 - 730 feet
- Data: USGS Data Release
- Publication:
- Eastern, Middle, and Western Sacramento Valley
- Dates Sampled: 2005 - 2008
- Depths Sampled:
- Data: USGS Data Series 385
- Publication: USGS SIR 2011-5002
Central San Joaquin Valley
- Modesto, Turlock, and Merced Areas
- Dates Sampled: September 2020 - March 2021
- Depths Sampled: 32 - 645 feet
- Data: USGS Data Release
- Publication: USGS Open-File Report 2022-1116
- Modesto, Turlock, and Merced Areas
- Dates Sampled: Spring 2006
- Depths Sampled: 75 - 293 feet
- Data: USGS Data Series 325
- Publication: USGS SIR 2009-5266
Coachella Valley Area
- Coachella Valley
- Dates Sampled: January - June 2020
- Depths Sampled: 80 - 900 feet
- Data: USGS Data Release
- Publication: USGS Open-File Report 2022-1122
- Coachella Valley
- Dates Sampled: Spring 2007
- Depths Sampled: 240 - 1,200 feet
- Data: USGS Data Series 373
- Publication: USGS Factsheet 2012-3098
E. San Joaquin Area
- East San Joaquin
- Dates Sampled: July - September 2019
- Depths Sampled: 60 - 460 feet
- Data: USGS Data Release
- Publication: USGS SIR 2023–5049
- North San Joaquin
- Dates Sampled: 2004 - 2005
- Depths Sampled: 250 - 500 feet
- Data: USGS Data Series 196
- Publication: USGS Fact Sheet 2010-3079
N. Sacramento Valley
- Redding - Red Bluff
- Dates Sampled: December 2018 - April 2019
- Depths Sampled: 65 - 350 feet
- Data: USGS Data Release
- Publication: USGS Fact Sheet 2020-3025
- North Sacramento
- Dates Sampled: 2007 - 2008
- Depths Sampled: 200 - 400 feet
- Data: USGS Data Series 452
- Publication: USGS Fact Sheet 2011-3004
Mojave
- Mojave
- Dates Sampled: January - May 2018
- Depths Sampled: 50 - 250 feet
- Data: USGS Data Release
- Publication: USGS Fact Sheet 2019-3033
- Mojave
- Dates Sampled: 2008
- Depths Sampled: 200 - 1,000 feet
- Data: USGS Data Series 440
- Publication: USGS Fact Sheet 2012-3036