What should I test for?
Six quick questions about your well and household. Get a test list with the reason for each item.
Start the helperOfficial well-water data, one search away
Is your well water safe? Start with the facts.
Certified drinking-water labs from official state and provincial lists, with the source and licence behind every record. Free and neutral. We don't sell filters.
| California ELAP accreditation | 457 |
| EGLE certified | 206 |
| Pennsylvania DEP accreditation | 168 |
| Virginia DCLS certification | 145 |
| Ohio EPA certification | 75 |
| Wisconsin DNR certification | 72 |
| Maine CDC accredited | 49 |
| NJDEP certified | 39 |
| MassDEP certified | 36 |
| Minnesota MDH accreditation | 25 |
| Listed by NHDES | 8 |
We are adding jurisdictions one official list at a time. Every lab links to the government list it came from.
1,280certified labs listed
11official lists
2026-10-17last refreshed
Certified labs
See all labs →Preston, Minnesota · (507) 765-3878
Bacteria (coliform / E. coli)
North Swanzey, New Hampshire · (603) 357-2577
Bacteria (coliform / E. coli)
International Falls, Minnesota · (218) 283-7070
Bacteria (coliform / E. coli)
Aquinnah, Massachusetts · (508) 645-2903
Bacteria (coliform / E. coli)
Derry, New Hampshire · (603) 432-3044
Bacteria (coliform / E. coli)Radioactivity
Labs by certifying list
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Where the data comes from
View all data sources →- California Water Boards – ELAP drinking water accredited laboratoriesPublic record (California State Water Resources Control Board) · 457 · 2026-10-17
- Michigan EGLE – Certified drinking water laboratories: chemistry, microbiology, lead & copper (3/11/2026)Public record (Michigan EGLE) · 206 · 2026-10-17
- Pennsylvania DEP – Accredited Labs Report, drinking water (chemistry 2024-06-11, microbiology 2024-06-13)Public record (Pennsylvania DEP) · 168 · 2026-10-17
- Virginia DCLS – Drinking water certified laboratoriesPublic record (Virginia DGS) · 145 · 2026-10-17
- Ohio EPA – Laboratories certified/accepted for public drinking water (Oct 2026)Public record (Ohio EPA) · 75 · 2026-10-17
- Wisconsin DNR – Drinking water certified labs (NR 809/812)Public record (Wisconsin DNR) · 72 · 2026-10-17
- Maine CDC – All accredited laboratories (Safe Drinking Water Program analytes active on the file date)Public record (Maine CDC) · 49 · 2026-10-17
- NJDEP Data Miner – Certified Drinking Water Labs (export downloaded 2026-10-17)Public record (NJDEP) · 39 · 2026-10-17
- MassDEP – Certified labs offering services to private well owners (12/18/2025)Public record (MassDEP) · 36 · 2026-10-17
- Minnesota Department of Health – Accredited labs accepting private well samples (Oct 2026)Public record (Minnesota Department of Health) · 25 · 2026-10-17
- NHDES – Water Testing Guidance for Private Well Users (April 2026; lab table updated 9/20/2024)Public record (NHDES) · 8 · 2026-10-17