Enterococci is a family of bacteria that lives in the intestines of mammals, birds, insects and reptiles, including humans, where it plays a functional role in our digestion.  Out of balance, Enterococci  bacteria can blossom into bodily infections from common urinary tract infections  (UTIs) to meningitis and heart infections.

In the environmental field, Enterococci are the indicator organisms of choice for detecting fecal pollution in fresh and salt water recreational settings.  Enterococci get into water through animal and human waste directly, accidental sewage treatment plant discharges, run-off from land, boats discharging sewage, and septic system failures.  The Enterococci test is preferred over the Total Coliform/E. coli test because Enterococci  survive in salt water longer than E. coli.

Maine Environmental Laboratory uses the IDEXX Enterolert method for testing Enterococci.  The test can read from 0-2419 colony forming units (cfu)/100 mL.  Results are available by the next day.

Heath Limit

The State of Maine posts health advisories at Maine beaches when the Enterococcus count tests above 104 colony-forming-units/100mL.

Additional Resources

Enterococcus - Wikipedia: https://en.wikipedia.org/wiki/Enterococcus

Healthy Maine Beaches, "Bacteria Fact Sheet"

“Enterococci and Their Interactions with the Intestinal Microbiome.” Dubin, Krista, and Eric G Pamer. Microbiology spectrum vol. 5,6 (2014):  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5691600/

"Enterococci in the Environment." Muruleedhara N. ByappanahalliMeredith B. NeversAsja KorajkicZachery R. StaleyValerie J.Harwood

Photo Credit: Janice Haney CDC/ Pete Wardell [fr. F. Lamiot]]

MEL Test Method for Enterococcus

Drinking Water  - not a compliance test

Ambient (fresh, marine, or estuarine surface water), groundwater, wastewater - Enterolert (EPA compliant)

Sample Requirements


Container: plastic or glass (certified sterile)
Volume: 100 mL
Hold Time: 8 hours (get sample to lab within 6 hrs, please)
Preservation: ≤6°C