The decision by St. Mary's College in southern Maryland to house some of its students on a docked cruise ship has prompted the state to close that area of the St. Mary's River to shellfish harvesting.

The move announced today puts off limits a portion of an oyster bar on the bottom of the river that is commercially harvested by local watermen. The Maryland Department of the Environment's release notes that a larger portion of the Seminary bar is already closed to harvesting because it's been declared an oyster sanctuary.

The college moved 250 students to a rented cruise ship, the Sea Voyager, while working to remove mold from their dormitories.  School officials have told state regulators they plan to collect wastewater in a holding tank onboard the rented 268-foot ship and periodically pump it to a wastewater treatment plant.  But MDE said it's closing nearby waters to shellfish harvesting because of the potential health risk from any spill or accidental discharge from the vessel.

The closure took effect Tuesday and will remain in effect until the cruise ship departs, according to MDE.

(Sea Voyager docked in St. Mary's River.  Washington Post photo)