All beaches on Plum Island in Newburyport reopened for swimming Sunday morning, while a New Hampshire ocean beach remains under advisory for high levels of fecal bacteria.

Swimming was prohibited at the Newburyport beaches on Friday, July 14, by the Massachusetts Department of Health after testing of the water revealed higher than acceptable bacteria levels.  The 55th Street was reopened Friday when new results showed the five-test average within the state allowable limit.

Test results came back Saturday evening from all Plum Island testing sites, with much lower levels. All beaches were open to swimming Sunday morning.

Two Plum Island beaches in Ipswich are also under advisory for high levels of bacteria.

The ocean water at North Hampton State Park Beach is under an advisory issued Friday for a high level of fecal bacteria. The next sample will be tested Monday, with the results due Tuesday.

Where is the Bacteria Coming From?

The EPA says possible sources of fecal bacteria include leaking septic systems, stormwater runoff, sewage discharged or dumped from recreational boats, domestic animal and wildlife waste, improper land application of manure or sewage, and runoff from manure storage areas, pastures, rangelands, and feedlots.

There are also natural, non-fecal sources of fecal indicator bacteria – including plants, sand, soil, and sediments – that contribute to a certain background level in ambient waters and vary based on local environmental and meteorological conditions.

Potential health risks from exposure to the contaminated water include nausea, vomiting, diarrhea, and fever.

Contact reporter Dan Alexander at Dan.Alexander@townsquaremedia.com or via Twitter @DanAlexanderNH

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