Part of an occasional series answering readers’ questions about Maine

Q. How do we know if it’s safe to swim at Maine beaches? Is anyone testing the water?

A: For Meagan Sims, the program coordinator of Maine Healthy Beaches, a lot of work goes into keeping beachgoers safe.

Along with volunteers and other employees of the Maine Department of Environmental Protection, Sims travels to more than 60 beaches around Maine, ranging from heavily trafficked city spots to the sparse coastal beaches and state parks, and tests the water for possible bacterial contamination. This meticulously cultivated information can be found updated regularly on the Maine DEP website.

The website mainehealthybeaches.org is the best place to check the most recent test results. Local beach managers may also post warning signs or close a beach after a positive test for contamination, although the state does not require it.

The state’s healthy beaches program monitors only ocean beach water, however. It’s up to local officials to monitor freshwater swim beaches, if they choose to.

The DEP defines a beach as contaminated if the water is above an EPA-approved Beach Action Value (BAV) of 104 MPN/100mL, the single sample maximum safety threshold for enterococci bacteria in the water. When results from a sample collected at a beach are above the BAV, Maine Healthy Beaches will recommend that participating towns or state parks issue a warning that swimming should be avoided.

The tests look for fecal bacteria, which also can indicate the presence of other pathogens. Beach water pollution causes a range of waterborne illnesses, including stomach flu, skin rashes, ear and eye infections and hepatitis.

Last week, according to the state’s website, six beaches recorded a Beach Action Value above 104, in communities such as South Portland, Kennebunk and Harpswell.

According to Sims, these instances of contaminated water are often caused by a beach’s proximity to freshwater inputs, such as streams, rivers, and stormwater drains. Additionally, when it rains, bacteria can be transported from the land to nearby water resources that, in many cases, flow to downstream beaches.

The level of contamination can also range wildly, with Willard Beach in South Portland recording only 108 BAV on Wednesday, while one test of Gooch’s Beach in Kennebunk revealed a BAV of 1,317. This reading was from a watershed at Gooch’s, according to Sims, where local river systems meet the ocean. It is unsafe to swim when the BAV is over 104, according to Sims.

In fact, Sims finds herself avoiding swimming anytime it has recently rained.

“Because I know what I know (through working at the DEP), I don’t swim at beaches after it rains,” said Sims. “And I don’t have my kids swim at the beaches after it’s raining because in Maine we’re quite unique with a lot of our swim beaches associated with freshwater inputs.”

While Maine Healthy Beaches and the DEP send regular reports to beach managers and towns around Maine regarding the contamination of the water, they do not have the power to close the beaches or require that warning signs be posted. Instead, those decisions are left up to those who directly oversee each beach, usually a designated official in that town or city.

A beach manager may post warning signs for a day or two after a positive test before taking them down, while state advisories remain until another test is conducted, which could take a week or more given all the beaches that staff and volunteers are monitoring.

A sign at Willard Beach in South Portland advises beachgoers of the color-coded system for water quality. Willard is among several coastal beaches that participate in regular water testing. Ben McCanna/Staff Photographer

For instance, in South Portland on Friday, even as the contamination advisory remained on the Maine Healthy Beaches website, Willard Beach was fully open without warning of contamination. That’s because officials in charge of the beach had deemed that enough tides had cycled in and out after the positive contamination test to remove any hazards.

That makes sense, according to Sims, who, through the process of resampling, has found that the beach often does a good job cleaning itself after a heavy rainfall.

“When there’s been heavy rainfall recently, … we recommend that (beaches) post a rainfall advisory for 24 hours … (or) two tide cycles to allow (the beach) to flush out,” said Sims. “What we’ve found by doing these resampling events … after high bacteria counts is that typically the water does a pretty great job of flushing out with the tides.”

Alex Beecher, a recent graduate of South Portland High School and the lifeguard on duty Friday at Willard Beach, said they had been informed of the recent contamination report and had taken the necessary steps such as posting a sign explaining the heightened level of risk at the front of beach and flying a yellow flag the day after the initial test was received.

“We test Mondays and Wednesdays,” said Beecher. “When the count is high, it is (often after it) rains and it comes from the stormwater drain.”

The state tests the water at dozens of beaches from the New Hampshire border to Acadia National Park, but not every ocean beach in Maine is monitored.

Cities, towns and parks must first request testing before Maine Healthy Beaches will begin to collect samples from a beach. Most participating beaches are tested once a week. Some, like Willard Beach, are tested more frequently, while others are tested less frequently.

Lifeguard Alex Beecher surveys the water at Willard Beach on Friday. Ben McCanna/Staff Photographer

According to Sims, the frequency of testing is determined by volunteer availability, as well as by using a risk assessment that takes into account the historic water quality and factors such as population density, the proximity of freshwater outlets, the presence of a sewage treatment plant or a local septic system, and others. Many of the beaches that are not monitored weekly are in state parks where there are few local residents visiting the beaches regularly.

Some beachgoers in southern Maine last week said they had no idea that the water was being tested regularly, or that the data from those tests was available online.

Jenny Predick of South Portland was visiting Willard Beach on Friday with her two sons, a 3-year-old and an 8-month-old.

“I didn’t know there was a website,” said Predick. “No one knows to look” for reports of contamination.

Heidi and Caroline Keller of Falmouth, a mother-daughter pair, were also at Willard Beach.

“I was pretty confident,” said Heidi Keller. “That’s why I went in.” Her daughter added that the beach “doesn’t smell bad like beaches in Massachusetts.”