Summer means spending time by the sea, and luckily there are plenty of Boston beaches, and even more just outside of the city.
But not all beaches are equal: The water quality at some beaches can be better than at others, providing a safer summer setting for your swims, and a new report by an environmental advocacy organization breaks down which metro Boston beaches are best.
Save the Harbor/Save the Bay, an environmental nonprofit made up of scientists and regular concerned citizens, has created a Beach Water Quality Report Card for beaches in the Boston Metro region.
For the report card, scientists tested water from 15 public beaches that had been collected during the 2017 beach season. To determine the water quality, the report looked at what percentage of the test samples exceeded the state swimming standard, which is 104 colony forming units of a bacteria called enterococcus in 100 milliliters of water.
In total, the 15 of the metro Boston beaches were deemed safe for swimming 94 percent of the time in 2017, according to the report. That’s actually a decrease in water quality from 2016, when these beaches were deemed safe for swimming 96 percent of the time.
The report then breaks down the 15 beaches near Boston by safety. The Boston beaches M Street, City Point, Carson Beach and Pleasure Bay were deemed the safest with ratings of 100 percent. Nahant Beach also came out among the top, and Revere and Nantasket were right behind.
Though some Boston beaches were deemed perfectly safe, others in the city didn’t fare so well. Tenean Beach in Dorchester had one of the lowest safety ratings at 81 percent with 28 of the 87 water samples tested exceeding the safe bacterial level. Tenean Beach will post a red flag when there is a bacterial count greater than that state swimming standard, and in 2017, Tenean Beach had 31 flag postings, according to the report.
2017 safety rating of metro Boston beaches
M Street Beach —100%
Carson Beach — 100%
Pleasure Bay — 100%
Nahant Beach — 100%
Nantasket — 98%
Revere Beach — 98%
Constitution Beach — 95%
City Point Beach — 94%
Winthrop Beach — 94%
Savin Hill Beach — 94%
Wollaston Beach — 92%
King’s Beach — 92%
Malibu Beach — 91%
Tenean Beach — 81%
Short Beach — 80%