Quick answer
About 1,000 people in District of Columbia (0.1% of residents) got their water from private wells in 2010, according to USGS estimates. District of Columbia Department of Energy and Environment (DOEE) runs the state’s private well guidance. We didn’t find a free statewide well testing program in District of Columbia. Certified labs charge for each test, and some county health departments offer lower-cost bacteria and nitrate tests.
- People on private wells
- 576
- Share of residents
- 0.1%
- Rank among states
- 49th
- Well users modeled above 10 µg/L arsenic
- 3.1%
Where to get your well tested in District of Columbia
- District of Columbia Department of Energy and Environment (DOEE): Well and Boring Permits, the state’s guidance for private well owners.
Free or low-cost testing
We didn’t find a free statewide program in District of Columbia. Certified labs charge per test; county health departments sometimes offer lower-cost bacteria and nitrate tests.
Mail-in lab kits are another option when no local lab is convenient. See well water test kits for what home kits can and can’t tell you.
What to test for
- Every year: total coliform bacteria and nitrate.
- Before buying equipment: pH, hardness, iron, manganese and, if there’s a smell, hydrogen sulfide.
- Based on location: arsenic, uranium and radon, PFAS, and lead in older plumbing.
Private wells by county
Estimated people relying on private wells in each District of Columbia county in 2010, the share of residents that represents, and the modeled share of well users with arsenic above 10 µg/L. These are USGS model estimates (2010 population), not measurements of any well. Arsenic is hidden for counties with fewer than 500 well users.
| County | People on wells | Share | Arsenic >10 µg/L |
|---|---|---|---|
| District of Columbia | 576 | 0.1% | 3.0% |
After you get results
Enter your numbers in the test results tool to see what needs treating and in what order. The guide to reading a well water test explains units and limits.
Common questions
Does District of Columbia offer free well water testing?
We didn’t find a free statewide well testing program in District of Columbia. Certified labs charge for each test, and some county health departments offer lower-cost bacteria and nitrate tests.
Who oversees private wells in District of Columbia?
District of Columbia Department of Energy and Environment (DOEE) (Well and Boring Permits) publishes guidance for private well owners. Private wells aren’t covered by the federal Safe Drinking Water Act, so testing and treatment are up to the owner.
How many people use private wells in District of Columbia?
USGS estimates about 1,000 people, or 0.1% of the population in 2010. That ranks 49th of the states covered by the estimate.
What should I test my well for in District of Columbia?
Test every year for total coliform bacteria and nitrate, plus pH, hardness, iron and manganese before buying equipment. Ask the state program or a certified lab about local concerns such as arsenic, uranium or PFAS.