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!
Resources
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
Biotoxin Information: Maine Department of Marine Resources: https://www.maine.gov/dmr/fisheries/shellfish/bureau-of-public-health-programs/biotoxins-in-maine
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/
