Groundwater Info Center
California Well Standards

DWR has responsibility under the Water Code for developing well construction, alteration, and destruction standards for the purpose of protecting groundwater quality. DWR Well Standards are published under the Bulletin 74 series.

From Standards to Regulations

Through a process detailed in the Water Code, the State Water Resources Control Board has authority to adopt DWR Well Standards into a statewide Model Well Ordinance; and cities, counties, or water agencies have authority to adopt a local ordinance that meets or exceeds DWR Well Standards. If no local ordinance is adopted, the Model Well Ordinance takes effect in that jurisdiction. Well ordinances are enforced by Local Enforcing Agencies.


Statewide Publications

Statewide Advisory: Sealing Materials for Water Wells, Monitoring Wells, Cathodic Protection Wells, and Geothermal Heat Exchange Wells, September 2015

Bulletin 74-90: California Well Standards, June 1991 [PDF 21.32MB]
Together with Bulletin 74-81, this supplement addresses minimum standards for construction, alteration, maintenance, and destruction of water wells, monitoring wells, and cathodic protection wells in California. Although still a draft, many local agencies have adopted Bulletin 74-90 standards into their local ordinances.

Bulletin 74-81: Water Well Standards - State of California, December 1981 [PDF 21.70MB]
Bulletin 74-81 includes minimum standards for the construction and destruction of water wells, subsequently updated in the draft supplement, Bulletin 74-90 - see above.

Bulletins 74-90 and 74-81, Combined
To facilitate ease of use of the Well Standards, DWR's Southern Region Office combined Bulletin 74-81 with the draft supplement, Bulletin 74-90, in this online publication.

Geothermal Heat Exchange Wells
In 1996, the Legislature named geothermal heat exchange wells, also known as ground source heat pumps, as a well type requiring statewide standards for groundwater protection. DWR published Draft Geothermal Heat Exchange Well Standards in April 1999 [PDF 174KB]. In 2012, DWR began the process of updating the Geothermal Heat Exchange Well Standards. Please visit the project website for more information.

California Laws for Wells, October 2016 [PDF 813KB]
This booklet contains California State statutes that relate directly to the construction, alteration, maintenance, and destruction of water wells, monitoring wells, cathodic protection wells, and geothermal heat exchange wells.

Water Facts 5. California Well Standards Questions and Answers, June 1992 [PDF 54KB]
Water Facts are short reports on water resources issues of general interest. This Water Facts answers five commonly-asked questions about DWR's well standards. Other Water Facts related to groundwater can be viewed here.

Regional Publications

Bulletin 74-2: Recommended Minimum Water Well Construction and Sealing Standards for the Protection of Ground Water Quality, Alameda County. Preliminary Edition, 1962 [PDF 4.0MB]

Bulletin 74-3: Water Well Standards Del Norte County, 1966 [PDF 5.7MB]

Bulletin 74-4: Water Well Standards. Central, Hollywood, Santa Monica Basins, Los Angeles County, 1974 [PDF 1.1MB]

Bulletin 74-5: Water Well Standards: San Joaquin County. Final Supplement, 1969 [PDF 2.1MB]

Bulletin 74-5: Water Well Standards: San Joaquin County. Appendix E: Formation Testing. Preliminary Editon, 1965 [PDF 2.1MB]

Bulletin 74-6: Water Well Standards: Fresno County, 1968 [PDF 2.1MB]

Bulletin 74-7: Water Well Standards Arroyo Grande Basin San Luis Obispo County, 1971 [PDF 1.7MB]

Bulletin 74-8: Water Well Standards Shasta County, 1968 [PDF 6.7MB]

Bulletin 74-9: Water Well Standards Ventura County, 1968 [PDF 4.1MB]