Nitrate Water Testing Labs in Rhode Island (4 state-certified labs)

How many labs test for nitrate in Rhode Island

4 labs on Rhode Island's official drinking-water lab list are certified to test for nitrate. All 4 are named for nitrate on the list. 4 of them are marked as taking samples from the public. They are listed first.

The list is published by the Rhode Island Department of Health (RIDOH) - Center for Drinking Water Quality and State Health Laboratories, laboratory certification. List versions on file: page as fetched 2026-11-07 (no date printed); certificate appendix issued 1/21/2026; page as fetched 2026-11-07 (no date printed); certificate appendix issued 3/12/2026; page as fetched 2026-11-07 (no date printed); certificate appendix issued 3/24/2026. Fetched 2026-11-07 (UTC).

Rhode Island labs certified for nitrate

Marked as taking public samples (4)

How the Rhode Island list marks public samples (whole list). Yes for the labs on RIDOH's 'Certified Drinking Water Testing Labs' page, which says they "provide analytical services for a fee to individuals and public water systems". Not stated for the other out-of-state labs.

Before you send a sample, call the lab to confirm it is currently certified for the exact test and method, that it accepts samples from homeowners, and how to collect and ship them. Status can change between list updates.

Why test for nitrate in Rhode Island

Nitrate has no taste or smell, and a lab report can state the same water in two units that differ by a factor of 4.43. Read our nitrate explainer.

EPA advises private-well owners to test every year for total coliform bacteria, nitrates, total dissolved solids and pH. [1]

Rhode Island guidance that mentions nitrate:

• The Rhode Island Department of Health (RIDOH) recommends three routine sets of tests for private wells. Every year: coliform bacteria, nitrate/nitrite, color, chloride, sodium and turbidity. Every three to five years: metals, corrosivity and hardness. Every five to 10 years: volatile organic compounds and MTBE. If you have had problems before or are at higher risk for certain things (such as iron-rich soil or worn copper pipes), RIDOH says to test for those more often. [2]
• RIDOH and the University of Rhode Island (URI) offer tip sheets on common well issues such as bacteria, iron and nitrates. You can call RIDOH's Private Wells Program or URI's Water Quality Program about your concerns, or ask the lab that tested your water to let you speak to a licensed interpreter. [2]

About 112,853 people in Rhode Island used private wells in 2015, by the USGS estimate of people on domestic self-supplied water. [3] Federal limits are written for public water systems, not private wells, so testing is up to the owner.

For tests that depend on your home (farms nearby, old plumbing, a new baby), use the which-tests checklist. When results arrive, check your numbers against EPA's limits. State guidance, county data and every lab: Rhode Island.

Other tests in Rhode Island