Environmental Testing of Ocean Water

Ocean water quality is relatively unregulated, compared to the rigorous regulation that exists for US surface waters, groundwater, lakes and streams (which regulatory burden provides the bulk of our customers).  Of the ocean water testing that does go on in Maine, one of the major players is The Maine Healthy Beaches Program (MHB), which monitors the water quality of over 60 beaches along the coast of Maine.  Their mission is to keep beach users safe from bacterial pollution. When a beach gets an elevated Enterococcus result, MHB gets the word out and posts contamination advisories. Between Memorial Day and Labor Day, MHB program volunteers typically collect water samples tested for Enterococcus, and record environmental parameters such as temperature, recent rainfall, salinity, and tide stage.

Government  regulation has done a lot to eliminate practices that used to pollute the water, such emptying sewage directly into shoreland recreation zones, but the system is still susceptible to accidental discharges, and inadvertent overflows after heavy rains and spring flooding are not uncommon.

The main barometer used to measure the bacterial cleanliness of salt water is a test for Enterococci bacteria.  Enterococci is an indicator organism that points to the presence of even more unsavory companions, such as fecal coliform bacteria and other pathogens.  Enterococci are measured in most-probably-number (MPN) of colony-forming-units (CFU) per 100mL of water.  A result greater than 104 MPN/100mL is considered high enough to trigger resampling or a temporary contamination advisory. Real-time results of bacteria tests from participating Maine beaches are posted on the MHB Check Beach Status page.

In Maine, the State Laboratory Certification body accepts the following methods for testing for Enterococcus: SM9230, EPA1106, EPA600, EPA1600, and IDEXX's Enterolert.  Method ASTMD5259, published in 2014, is not yet accepted in Maine. Maine Environmental Lab is certified to perform Enterococcus testing using the Enterolert method.

Aquaculture and the Future of Ocean Water Testing

In addition to the State's already established testing program for Red Tide and related biotoxins, the growth of salt-water aquaculture in Maine waters should bring with it increased testing for nitrogen and phosphorus pollution from dense communities of confined fish, even in areas where tides perform a cleansing function.

MEL can test salt water samples and we are currently working with several aquaculture companies to perform analytical testing using our existing methods, as well investigating ways to adapt our methods to individual company requirements.  Give us a call to see what we can do for you!


MEL webpage: "Enterococci Bacteria"

Maine Healthy Beaches:  http://www.mainehealthybeaches.org/

Maine Healthy Beaches "Monitoring, Notifications, and Illness": https://www.maine.gov/dep/water/beaches/monitoring.html

Maine Healthy Beaches "Bacteria Fact Sheet": http://www.mainehealthybeaches.org/documents/Bacteria_Fact_Sheet.pdf

Maine Center for Disease Control "Recreational Water Illness" (webpage): http://www.maine.gov/dhhs/mecdc/infectious-disease/epi/healthyswimming/index.shtml

State of Maine Shellfish Sanitation and Management webpage: https://www.maine.gov/dmr/fisheries/shellfish/shellfish-sanitation-management-program

Biotoxin Information: Maine Department of Marine Resources: https://www.maine.gov/dmr/shellfish-sanitation-management/programs/biotoxininfo.html#Testing

EPA Beaches (webpage): https://www.epa.gov/beaches

EPA Beach Advisory and Closing Online Notification (aka BEACON) Maps - zoom in to see recent results for salinity, Enterococci and temperatures from beaches near you: https://watersgeo.epa.gov/beacon2/beacon.html

[INTERESTING READ - WHERE THE STANDARD CAME FROM:] Federal Register "Water Quality Standards for Coastal and Great Lakes Recreation Waters" (2004):  https://www.federalregister.gov/documents/2004/11/16/04-25303/water-quality-standards-for-coastal-and-great-lakes-recreation-waters

Gulf of Maine Research Institute (website) - this non-profit conducts local ocean monitoring work on all parts of the ecosystem: https://www.gmri.org/


2023: We are pleased to announce that we have been selected by the
Maine Healthy Beaches Program
to perform Enterococcus testing up and down the coast of Maine for the 2023 beach season!

Maine Healthy Beaches sign post. Photo by Joe Shlabotnik.

Maine Healthy Beaches sign post. Photo by Joe Shlabotnik.

Worth a Listen...

Coastal Conversations Radio Program
A co-production of WERU and Maine Sea Grant

"...Coastal Conversations is a public affairs program that explores current issues facing Maine’s coastal communities through conversations with people who live, work, and play on our coast. From fisheries to tourism, from energy to environment, from economy to ecology, Coastal Conversations goes beyond the social media sound bites, probing deeply into complex issues facing our coast and the creative solutions Maine people are using to solve them."

Recent topics include: women in fisheries, The Maine Ocean School, Maine birds, clams, seaweed ecology, biotoxins and red tide, and much more...

The show airs on the fourth Friday of each month from 10 to 11 AM and streams online at www.WERU.org. Programs are archived back to 2015...