Press Release

BALTIMORE, MD (August 26, 2011) – With Hurricane Irene bringing the potential for flooding and large amounts of stormwater runoff, the Maryland Department of the Environment has issued an emergency closure to shellfish harvesting in Maryland waters.

MDE is temporarily closing the Maryland portion of the Chesapeake Bay, including all tributaries, and Maryland’s coastal bays to shellfish harvesting effective Sunday, Aug. 28. Areas previously open to shellfish harvesting are to reopen for shellfish harvesting Saturday, Sept. 3.

The closure could remain in effect beyond that date if water-quality monitoring shows additional concerns. It could be lifted before that date if the storm’s effects on water quality are less than expected.

The closure applies only to the harvesting of shellfish (oysters and clams); it does not apply to fishing or crabbing.

“Maryland is taking this emergency action to prevent the potentially harmful effects of eating shellfish exposed to contaminated waters,” said MDE Secretary Robert M. Summers. “This ensures that Maryland maintains its reputation for safe and wholesome seafood products.”

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. The Department is required to close areas that do not meet the strict water quality standards for shellfish harvesting waters, and it has a longstanding policy to reopen areas to shellfish harvesting when water quality improves. These actions ensure that Maryland remains in compliance with the requirements of the National Shellfish Sanitation Program.

As Hurricane Irene approached Maryland, MDE determined that tidal flooding from the storm could affect septic systems and cause sewer systems to overflow, creating the potential for shellfish harvesting waters to be contaminated. Receding tides and large amounts of stormwater runoff could also carry contaminants to waterways.

The commercial oyster season in Maryland does not begin until October 1, and it is anticipated that the effects on shellfish water quality from Irene will have dissipated by then. The emergency closure affects, in addition to the harvesting of clams, the harvesting of oysters from leased beds and through aquaculture operations. Those oysters can normally be harvested throughout the year.

MDE issued a similar, week-long emergency closure to shellfish harvesting in the Chesapeake Bay and its tributaries due to flooding caused by Tropical Storm Isabel in September 2003.

For additional information on Maryland’s preparations for Hurricane Irene, go to