Current Requirements

According to Oregon Revised Statute (ORS) 448.271(1), when selling real estate that includes a domestic well, property owners are required to test the water for arsenic, nitrate, and total coliform bacteria. Domestic wells are those used for drinking and other household purposes. Test results must be reported within 90 days to the real estate buyer and Drinking Water Services after the seller receives the test results.

Collecting Water Samples

Samples must be collected (for current and future requirements above) according to Oregon Administrative Rule (OAR) 333-061-0335, and through OAR 333-061-0330 samples must be analyzed by an accredited laboratory. A list of accredited laboratories for domestic well testing can be found by clicking here (pdf).

Testing Form

The Domestic Well Testing Reporting form (pdf) is required for all real estate transactions when there is a domestic well on the property. (Note: Springs DO NOT need to be tested under these regulations.) Use the Oregon Water Resources Department's Well Log Query to search for well information.

Test Results

Residential water quality testing results can be accessed from the Pacific Northwest Water Quality Data Exchange. Information on how to retrieve data from the Exchange is provided in DEQ's Residential Well Owners - Water Quality Test Results fact sheet (pdf).

Who needs to comply, who can collect water samples, and other frequently asked questions

Visit the Domestic Well Testing & Real Estate Transaction FAQs page for answers to frequent questions about domestic well testing and real estate transactions.

More information about domestic well testing and contaminants commonly found in well water

• Fact Sheet: Arsenic
• Fact Sheet: Coliform Bacteria (pdf)
• Fact Sheet: Nitrate (pdf); for Spanish version, click here (pdf)
• Collecting a Water Sample (pdf)
• OARs and Domestic Well Testing

Information on well maintenance, filtration options, and more

• Oregon State University Extension Service Well Water Program: More information on wells, groundwater, and real estate transactions.
• EPA's Private Drinking Water Wells Information
• Free Online Training for Private Well Owners: "The Private Well Class" is a free online course that helps homeowners understand and care for their water well. This class is a project of the Rural Community Assistance Partnership and the Illinois State Water Survey/Illinois Water Resources Center at the University of Illinois at Urbana-Champaign, through a grant from the U.S. Environmental Protection Agency.
• Fact Sheet: How to Disinfect a Well (pdf)
• Private Well Fact Sheet (pdf): Brief description of private wells (including the construction components), well protection, and private well testing. Web resources are included.
• Centers for Disease Control and Prevention (CDC): About drinking water from private wells
• National Ground Water Association's Well Owners Web page: Information about private water well systems and ground water.
• Oregon Department of Environmental Quality: More information for private well owners
• Consumer Comparison for Water Treatment Options