38 named for coliform bacteria itself on the list.
Per the state list or a state web page. Call to confirm.
Located outside Maryland but on its list.
USGS estimate for Maryland.
How many labs test for coliform bacteria in Maryland
38 labs on Maryland's official drinking-water lab list are certified to test for coliform bacteria. All 38 are named for coliform bacteria on the list. The Maryland list does not say which labs take samples from homeowners, so call a lab before you send one. 16 are located outside Maryland.
The list is published by the Maryland Department of the Environment (MDE) - Water Supply Program, Laboratory Certification Program. List versions on file: Latest Revisions: 10/1/2026; Latest Revisions: 10/1/2026; PFAS list Last Rev 101/2026. Fetched 2026-11-07 (UTC).
Maryland labs certified for coliform bacteria
| Lab | Location | Bacteria certification | Public samples | Cert. expiry |
|---|---|---|---|---|
| ALS ENVIRONMENTAL - MIDDLETOWN | Middletown, PA | Named on the official list | Public samples: ask the lab | Not on the list |
| ASHBURTON WATER QUALITY LABORATORY | Baltimore, MD | Named on the official list | Public samples: ask the lab | Not on the list |
| CERTIFIED WATER TESTING, LLC | Thurmont, MD | Named on the official list | Public samples: ask the lab | Not on the list |
| CHESAPEAKE ENVIRONMENTAL LABORATORY, INC | Stevensville, MD | Named on the official list | Public samples: ask the lab | Not on the list |
| DEEP CREEK LAKE LABORATORY | Oakland, MD | Named on the official list | Public samples: ask the lab | Not on the list |
| EMSL ANALYTICAL, INC - BELTSVILLE | Beltsville, MD | Named on the official list | Public samples: ask the lab | Not on the list |
| EUROFINS POMONA (formerly Eurofins Eaton Analytical-Monrovia) | Pomona, CA | Named on the official list | Public samples: ask the lab | Not on the list |
| EUROFINS SOUTH BEND (formerly Eurofins Eaton Analytical, LLC-South Bend) | South Bend, IN | Named on the official list | Public samples: ask the lab | Not on the list |
| FOUNTAIN VALLEY ANALYTICAL LABORATORY, INC | Westminster, MD | Named on the official list | Public samples: ask the lab | Not on the list |
| FREDERICKTOWNE LABS, INC | Myersville, MD | Named on the official list | Public samples: ask the lab | Not on the list |
| H2O ENVIRONMENTAL | Harrisburg, PA | Named on the official list | Public samples: ask the lab | Not on the list |
| HOME LAND LABS - ANNAPOLIS | Annapolis, MD | Named on the official list | Public samples: ask the lab | Not on the list |
| HOME LAND LABS - FOREST HILL | Forest Hill, MD | Named on the official list | Public samples: ask the lab | Not on the list |
| HOME LAND LABS - TOWSON | Towson, MD | Named on the official list | Public samples: ask the lab | Not on the list |
| HOME LAND LABS - WALDORF | Waldorf, MD | Named on the official list | Public samples: ask the lab | Not on the list |
| LABORATORY ANALYTICAL AND BIOLOGICAL SERVICES, INC (LABS INC) | New Oxford, PA | Named on the official list | Public samples: ask the lab | Not on the list |
| M. J. REIDER ASSOCIATES, INC | Reading, PA | Named on the official list | Public samples: ask the lab | Not on the list |
| MICROBAC LABORATORIES, INC - BALTIMORE | Baltimore, MD | Named on the official list | Public samples: ask the lab | Not on the list |
| MID-ATLANTIC LABORATORIES, INC | Port Royal, VA | Named on the official list | Public samples: ask the lab | Not on the list |
| MONTEBELLO WATER QUALITY LABORATORY | Baltimore, MD | Named on the official list | Public samples: ask the lab | Not on the list |
| NATIONAL TESTING LABORATORIES, LTD | Ypsilanti, MI | Named on the official list | Public samples: ask the lab | Not on the list |
| NIAGARA BOTTLING, LLC | Howard, PA | Named on the official list | Public samples: ask the lab | Not on the list |
| OAKWOOD SCIENTIFIC LAB | Mechanicsville, VA | Named on the official list | Public samples: ask the lab | Not on the list |
| ONTERRIS LABORATORIES, LLC- Richmond (formerly ENTHALPY ANALYTICAL, LLC- Richmond) | Richmond, VA | Named on the official list | Public samples: ask the lab | Not on the list |
| PACE ANALYTICAL - MOUNT JULIET - National Center for Testing & Innovation | Mount Juliet, TN | Named on the official list | Public samples: ask the lab | Not on the list |
| PACE ANALYTICAL SERVICES, LLC - ALTOONA | Altoona, PA | Named on the official list | Public samples: ask the lab | Not on the list |
| PURE-TEST LABORATORY | Myerstown, PA | Named on the official list | Public samples: ask the lab | Not on the list |
| SCHNEIDER LABORATORIES GLOBAL, INC | Richmond, VA | Named on the official list | Public samples: ask the lab | Not on the list |
| SPL-READING | Reading, PA | Named on the official list | Public samples: ask the lab | Not on the list |
| WASHINGTON COUNTY DIVISION OF ENVIRONMENTAL MANAGEMENT LABORATORY | Williamsport, MD | Named on the official list | Public samples: ask the lab | Not on the list |
| WATER TESTING LABS OF MD - SALISBURY | Salisbury, MD | Named on the official list | Public samples: ask the lab | Not on the list |
| WATER TESTING LABS OF MD - STEVENSVILLE | Stevensville, MD | Named on the official list | Public samples: ask the lab | Not on the list |
| ABINGDON WATER TREATMENT PLANT LABORATORY | Abingdon, MD | Named on the official list | Public samples: ask the lab Looks like a utility or municipal lab, judging by the name (our label, not the state list) | Not on the list |
| CITY OF FREDERICK WATER QUALITY LABORATORY | Frederick, MD | Named on the official list | Public samples: ask the lab Looks like a utility or municipal lab, judging by the name (our label, not the state list) | Not on the list |
| CITY OF HAGERSTOWN DW LABORATORY | Hagerstown, MD | Named on the official list | Public samples: ask the lab Looks like a utility or municipal lab, judging by the name (our label, not the state list) | Not on the list |
| FREDERICK COUNTY DIVISION OF WATER & SEWER UTILITIES LABORATORY | Frederick, MD | Named on the official list | Public samples: ask the lab Looks like a utility or municipal lab, judging by the name (our label, not the state list) | Not on the list |
| TOWN OF OCEAN CITY LABORATORY SERVICES | Ocean City, MD | Named on the official list | Public samples: ask the lab Looks like a utility or municipal lab, judging by the name (our label, not the state list) | Not on the list |
| WASHINGTON SUBURBAN SANITARY COMMISSION LABORATORY DIVISION (WSSC) | Silver Spring, MD | Named on the official list | Public samples: ask the lab Looks like a utility or municipal lab, judging by the name (our label, not the state list) | Not on the list |
How the Maryland list marks public samples (whole list). Not stated per lab. MDE's Be Well Wise page tells private well owners to "Have your water tested periodically by a state-certified laboratory that conducts a drinking water test", but neither that page nor MDE's list says which labs take samples from private well owners.
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 coliform bacteria in Maryland
About a third of the 397 domestic wells tested for bacteria in a national USGS study had total coliform. Read our coliform bacteria explainer.
EPA advises private-well owners to test every year for total coliform bacteria, nitrates, total dissolved solids and pH. [1]
Maryland guidance that mentions coliform bacteria:
- Maryland's Department of the Environment (MDE) says that at a minimum a well should be sampled every year, for total coliform bacteria, nitrates, total dissolved solids and pH. It also advises sampling any time you notice a change in odor, taste or appearance or suspect other contaminants. More frequent testing may be warranted, for example with unexplained illnesses in the family, a household member who is pregnant or nursing, or a contaminant found in a neighbor's water. [2]
- University of Maryland Extension recommends a comprehensive test if you have not tested in several years, then routine tests: coliform bacteria and nitrates every year, and pH, total dissolved solids and sulfates every 3 years. It also suggests checking with your local health department and county well permitting office about contaminants of local concern. [3]
- Maryland law (Real Property § 10-713, added by Chapter 587 of 2023, effective October 1, 2024) says a contract to sell real property with a private or domestic water supply well must include a provision requiring, as a condition of the sale, that the buyer make sure the well water is tested. Settlement may not take place until the seller and the buyer have each received and reviewed the results, and both certify this in writing at settlement. Results stay valid for 3 years, and the buyer may waive the testing in writing. The test must be done by a State-approved water sampler and a State-approved laboratory and cover at least bacteria, nitrate and turbidity (Environment § 9-4A-01). [4]
About 1,423,948 people in Maryland used private wells in 2015, by the USGS estimate of people on domestic self-supplied water. [5] 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: Maryland.
Other tests in Maryland
- U.S. EPA, Protect your home's water
- Maryland Department of the Environment, Water Supply Program, Be Well Wise
- University of Maryland Extension, Water Testing (updated Apr 29, 2021)
- Maryland Code, Real Property § 10-713, added by Chapter 587 of 2023 (HB 11, Private Well Safety Act of 2023), effective October 1, 2024 (read from the Internet Archive capture of October 17, 2026 of the enrolled chapter; the live legislature site did not connect)
- USGS, Estimated use of water in the United States, county-level data for 2015 (Dieter et al., ver. 2.0, 2018)
- Maryland's Certified Drinking Water Laboratories (MDE Laboratory Certification Program) (official list)
Maryland's Certified Drinking Water Laboratories (MDE Laboratory Certification Program).
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