Resources for Properties with Wells and Intakes
Wells or Intakes: Treatment/Filtration
Help with Treatment/Filtration Assessment:
California Rural Water Association:
- Please contact Dan DeMoss ddemoss@calruralwater.org for assessment of well or intake treatment/filtration system.
Operational Technical Services:
- Please contact David Sibelman david@getots.com for assessment of well or intake treatment/filtration system.
Residential Water Treatment Devices - information including CA registered devices with health-related claims that have been tested and certified
The importance of maintaining your Point of Entry (POE) water system
California State Water Resources Control Board
Information on Treating Drinking Water in Areas Where Cyanotoxins may be Present (We recommend that you share this with anyone advising on your treatment or filtration system):
- Walkerton (Canada) Clean Water Center: Fact Sheet
- National Collaborating Centre for Environmental Health (Canada): Report
Drinking Water Testing (for further testing of your water, if desired):
- Alpha Analytical Laboratories Inc (Ukiah)
- Brelje and Race Laboratories Inc (Santa Rosa)
- CLERC (Lake County, bacteriological only)
- Drinking Water Testing Factsheet (California Institute for Water Resources)
Additional analyses for microcystins is offered by the list of labs below:

Wells Only
Rural Community Assistance Corporation (RCAC): Please contact Phillip Rice price@rcac.org
Free Well Assessments: RCAC offers a program for free well assessments for homeowners. With this program an RCAC representative can visit a person's home, go over best practices for well care, and advise on resources available for homeowners to help address drinking water issues. This program works closely with the University of Illinois to bring education and resources to folks with issues. If any residents are interested, please request a free well assessment using the following links.
California Department of Pesticide Regulation Groundwater Protection Program: Free testing of well water for pesticides. Please contact GWPP@cdpr.ca.gov. or call 916-445-2262
Homeowners can also go here to sign up for free webinars, submit questions, and access their resource library.
Publicly Available Data and Tools
- State Water Resources Control Board GeoTracker - GeoTracker contains records for Cleanup Program Sites, Leaking Underground Storage Sites, Department of Defense Sites, and others.
- 2025 Aquifer Risk Map (Domestic Wells and State Small Water Systems) - This map displays raw source groundwater quality risk per square mile.
- Agricultural Pesticide Use in California - The Department of Pesticide Regulation (DPR) tracks pesticide use in California and provides this information to the public.
- Federal Emergency Management Agency (FEMA) National Flood Hazard Layer Viewer
- California Drinking Water System Area Boundaries - This tool provides service area boundaries of drinking water service providers verified by the Division of Drinking Water, State Water Resources Control Board.