How to Test Your Water, State by State

The four steps, wherever you live

1. Decide what to test for. Private well: total coliform bacteria, nitrate, TDS and pH every year, plus what your county health department says is common locally (arsenic, radon, uranium). City water: lead at your own tap if your home pre-dates 1986 or your service line is lead/unknown; otherwise start with your utility’s Consumer Confidence Report.
2. Pick a certified laboratory. Use the lab list published by your state’s drinking-water laboratory certification program (linked for every state below), or a certified mail-in lab. Certified labs use the same EPA-approved methods utilities must use and report numeric results with detection limits.
3. Collect the sample correctly. For lead, take a first-draw sample from a cold tap after the water has sat unused for at least 6 hours, aerator on, no flushing. For bacteria, use the sterile bottle the lab provides and get it to the lab (on ice) within the holding time it specifies — usually 24 to 30 hours.
4. Compare results to the limits. Lead action level 15 ppb (EPA’s goal is 0); nitrate 10 mg/L as N; arsenic 10 ppb; PFOA and PFOS 4 ppt each; total coliform should be absent. Each contaminant page on this site lists the limit and what removes it.

More: national how-to-test guide · kit vs lab · find your utility report · EPA CCR lookup · EPA private wells