Nearly 50 beaches are closed across Massachusetts on Sunday, Aug. 31.

There are 49 beaches closed, most due to excessive bacteria levels, according to the state Department of Public Health.

One of those is the main beach at Walden Pond State Reservation, which will remain closed for the entirety of summer 2025 as a new, state-of-the-art $6.1 million bathhouse is constructed. Red Cross Beach at Walden Pond will remain open, but without lifeguards.

Here is the full list of beach closures and reasons for closing on Sunday:

• Ashby: Damon Pond Beach — excess bacteria
• Ashland: Ashland Reservoir — Main Beach-excess bacteria
• Beverly: Woodbury — excess bacteria
• Billerica: Nutting Lake, Micozzi Beach at North and South — excess bacteria
• Braintree: Smith Beach — excess bacteria
• Brewster: Cliff Pond at DYS and Main — harmful cyanobacteria bloom
• Chicopee: Chicopee Beach — harmful cyanobacteria bloom
• Concord: Walden Pond – Main, due to construction
• Danvers: Sandy Beach — excess bacteria
• Essex: Centennial Grove beach — harmful cyanobacteria bloom
• Franklin: Chilson Beach — excess bacteria
• Georgetown: American Legion Park — excess bacteria
• Harwich: Seymour Pond — harmful cyanobacteria bloom
• Holden: Eagle Lake — excess bacteria
• Lynn: Kings on Eastern Ave., Kimball Road and Pierce Road — excess bacteria
• Mashpee: Santuit Pond at Bryants Neck and Town Landing — harmful cyanobacteria bloom
• Nantucket: Sesachacha Pond — excess bacteria
• Natick: Memorial Beach (Dug Pond) at Wading — excess bacteria
• North Andover: Frye Pond Beach and Stevens Pond – Center – due to excess bacteria
• Oxford: Carbuncle Pond — harmful cyanobacteria bloom
• Salem: Children’s Island, Back and Wally, and Ocean Avenue — excess bacteria
• Saugus: Pearce Lake at Breakheart Reservation — excess bacteria
• Sharon: Community Center Beach and Sharon Town Beach at Central — excess bacteria
• Sherborn: Farm Pond — harmful cyanobacteria exceedance
• Southwick: South Pond Beach — bacterial exceedance
• Springfield: Bass Pond at Right — cyanobacteria bloom, Camp Wilder at Right — excess bacteria and Paddle Club at Right— cyanobacteria bloom
• Templeton: Beamans Pond closed for campground and day-use activities — excess bacteria
• Tisbury: Hilman’s Pond — excess bacteria
• Townsend: Pearl Hill Pond Beach — excess bacteria
• Upton: Upton Town Beach — harmful cyanobacteria bloom
• Wareham: Shangri-La — harmful cyanobacteria bloom
• Westborough: Lake Chauncy Beach — harmful cyanobacteria bloom
• Wilmington: Wilmington Town Beach at Center and Right — excess bacteria
• Winchendon: Lake Dennison State Park at North Camp Beach — excess bacteria
• Winthrop: Donovans and Halford — excess bacteria

What are the risks?

Swimming in beach water that has high levels of bacteria can be risky and can result in illnesses, including:

• Gastrointestinal symptoms- nausea, vomiting, diarrhea and abdominal pain
• Respiratory symptoms- sore throat, cough, runny nose and sneezing
• Dermatological symptoms- skin rash and itching
• Eye and ear symptoms- irritation, earache, itching
• Flu-like symptoms- fever and chills

Stay aware of any warnings or beach closures that indicate that the water is not safe. Check the weather forecast, avoid swimming after heavy rain, watch for signs of water pollution like discolored, fast flowing and strong smelling water, do not swim near trash or litter floating in the water, avoid swallowing the water and swim in areas designated as “swim beaches.”

Although a beach could be posted, the public can still visit the location and take part in other activities that do not involve contact with the water. This can include anything from playing sports like volleyball or frisbee to sunbathing or collecting seashells or sea glass, DPH stated.

The public can also help to reduce contamination and pollution at the beach by:

• Cleaning up after pets
• Not feeding the birds as it encourages them to hang around the beaches, which increases fecal matter
• Using public restrooms
• Picking up and throwing away trash using public restrooms or properly disposing of it at home
• Not entering the water when sick or feeling unwell
• Changing diapers and putting plastic or rubber pants, known as swim diapers, on diapered children before they enter the water
• Not dumping anything down storm drains, as water moving through these drains does not get treated at a wastewater facility and flows directly into lakes and streams
• Avoiding the use of fertilizers and pesticides in yards since these chemicals can easily carry into the surface of waters during rain events and snowmelt
• Use walkways and avoid walking on dunes to prevent erosion and preserve vegetation that filters out pollutants from runoff before they reach the beach

More details from the DPH can be found here.