Certified labs by state
Pennsylvania
Pennsylvania is unusual because DEP explicitly says it does not regulate private homeowner wells, so well owners are responsible for testing and maintenance themselves. ([pa.gov](https://www.pa.gov/agencies/dep/residents/my-water/private-wells)) The Pennsylvania Department of Health says about 26% of Pennsylvania adults rely on private well water, and the main state-facing help pages are DEP for wells/labs and Penn State Extension for testing guidance. ([pa.gov](https://www.pa.gov/agencies/health/programs/environmental-health/well-water))
Checked against official sources on October 4, 2026. Rules and links change; confirm with the office listed before you act.
- Certifies drinking water labs
- Pennsylvania Department of Environmental Protection (DEP), Bureau of Laboratories, Laboratory Accreditation Program
- Free or low-cost testing
- PA DOH says its Environmental Health Capacity program is partnering with Penn State Extension’s Drinking Water Program to offer free water testing for private well owners; Penn State also advertises no-cost Safe Drinking Water Clinic workshops with limited free screening. ([pa.gov](https://www.pa.gov/agencies/health/programs/environmental-health/well-water))
Official resources in Pennsylvania
DEP’s homeowner hub for private wells links residents to contaminants, water testing, certified labs, treatment, and construction information. ([pa.gov](https://www.pa.gov/agencies/dep/residents/my-water/private-wells))
This DEP page explains lab accreditation and links to the official "Search PA Accredited Environmental Laboratories" tool. ([pa.gov](https://www.pa.gov/services/dep/apply-for-laboratory-accreditation))
DOH’s page covers private-well health information, a test-results guide, a checklist, and current free-testing information. ([pa.gov](https://www.pa.gov/agencies/health/programs/environmental-health/well-water))
Penn State Extension gives Pennsylvania-specific testing schedules and which extra tests to add based on nearby land use. ([extension.psu.edu](https://extension.psu.edu/testing-your-drinking-water?utm_source=openai))
These yearly county summaries help residents see which pollutants are most common locally before ordering extra tests. ([extension.psu.edu](https://extension.psu.edu/county-summaries-of-pennsylvania-groundwater-well-and-spring-data?utm_source=openai))
Key facts for Pennsylvania
- DEP says private homeowner wells are not regulated in Pennsylvania. ([pa.gov](https://www.pa.gov/agencies/dep/residents/my-water/private-wells))
- DEP accredits laboratories for drinking/potable water through its Laboratory Accreditation Program. ([pa.gov](https://www.pa.gov/services/dep/apply-for-laboratory-accreditation))
- Penn State recommends annual total coliform and E. coli testing for private water supplies. ([extension.psu.edu](https://extension.psu.edu/testing-your-drinking-water?utm_source=openai))
- Penn State recommends pH and total dissolved solids testing every three years. ([extension.psu.edu](https://extension.psu.edu/testing-your-drinking-water?utm_source=openai))
- Penn State says to add nitrate testing if a well is near fertilized cropland, manure application, or similar sources. ([extension.psu.edu](https://extension.psu.edu/potential-hidden-substances-in-the-groundwater-you-drink?utm_source=openai))
- PA DOH published a seven-county northern Pennsylvania well-water report for Bradford, Clinton, Lycoming, Pike, Potter, Sullivan, and Wayne counties. ([pa.gov](https://www.pa.gov/agencies/health/programs/environmental-health/well-water))
What to do next
- Start with DEP’s accredited-lab search or report, and confirm the lab is accredited for each analyte you want, not just general water testing. ([pa.gov](https://www.pa.gov/services/dep/apply-for-laboratory-accreditation))
- For routine maintenance, follow Penn State’s baseline schedule: yearly bacteria/E. coli and every three years pH/TDS; add nitrate when agriculture, manure, or septic sources are nearby. ([extension.psu.edu](https://extension.psu.edu/testing-your-drinking-water?utm_source=openai))
- Use Penn State’s county summaries, and if you are in northern PA also review DOH’s seven-county report, to decide whether to add region-specific tests such as arsenic, radon, PFAS, methane, or other contaminants. ([extension.psu.edu](https://extension.psu.edu/county-summaries-of-pennsylvania-groundwater-well-and-spring-data?utm_source=openai))
Helpful guides
- How to choose a state-certified drinking water lab
- What to test your private well water for (and how often)
- How to collect a well water sample without ruining the test
- How to read a water test report: MCLs, units and flags