Maryland’s Department of Environment has closed part of the Potomac River to shellfish harvesting, after a reported sewage overflow in St. Mary’s County.
The emergency order, issued Monday, affects about 180 acres of the river near St. George Island.
According to the department, the St. Mary’s County Metropolitan Commission reported the overflow on Monday. It began Nov. 24 and was stopped Sunday morning. The overflow reportedly entered ditches that drain into the Potomac.
About 2,500 gallons are estimated to have flowed into the river, “and an estimated 11,000 gallons were vacuumed from ditches,” the department said in a statement.
There are no aquaculture leases in the affected area, and while it’s unknown whether any commercial harvesting has happened since Wednesday, such harvesting is not allowed on weekends.
Because shellfish are filter feeders, overflows bring the risk of disease-causing organisms, especially in shellfish that are served raw or partially cooked. Such was the case recently, when contaminated oysters from St. George Creek, not far away, sickened dozens in Virginia. (That was blamed on an earlier sewage overflow.)
The department was set to sample the water starting Tuesday, and the area could reopen to shellfish harvesting as soon as Dec. 20.
The emergency closure does not apply to fishing and crabbing.
