The Maryland Department of the Environment has issued an order to temporarily close a portion of the Choptank River to shellfish harvesting due to a sewage overflow.

The emergency closure, issued May 2, became effective immediately to prevent the harvesting of oysters and other shellfish from the area in the immediate future. It applies to about 262 acres of the Choptank River near the mouth of Jenkins Creek.

MDE was notified last week of a sewage overflow following heavy rains and a reported blockage at a Cambridge Wastewater Treatment Plant pumping station.

The release of sewage flowed through swales and eventually a canal that drains to an area of the Choptank River that is approved for shellfish harvesting.

The overflow is reported to have begun April 30 and stopped May 1. An estimated 100,000 gallons of highly diluted wastewater is estimated to have been released into the river.

MDE is working in coordination with the Maryland Department of Natural Resources. There is no known shellfish harvesting occurring at this time in the affected area. Maryland Natural Resources police will patrol to ensure no harvest occurs during the closure period.

The closure will remain in effect until May 23, when the area will be reopened for shellfish harvesting.  

Shellfish are filter feeders with the ability to filter water and get food from microscopic organisms in the water. If the waters are polluted, this filtering process can concentrate disease-causing organisms associated with raw sewage and other sources, such as animal waste.

Oysters and clams are often eaten raw or partially cooked and must come from waters that are not polluted. MDE monitors bacteriological water quality and conducts pollution source surveys to determine which areas are safe for the harvesting of shellfish.

This order does not impact harvest in other areas that are approved or conditionally approved for shellfish harvest.

As a protection to consumers, all shellfish are to be tagged by harvesters and dealers as required under the National Shellfish Sanitation Program. Tags include the date and location of harvest and, in Maryland, can only come from approved or conditionally approved waters.