MARBLEHEAD – Town officials want to make it illegal for boat owners to dump sewage in Salem Harbor.The Harbors and Waters Board and selectmen have voted to sign on to Environmental Protection Agency New England’s goal to have the entire New England coastline designated No Discharge Areas (NDA) by 2010.At this time, only 440 miles of the 1,784 miles of the Massachusetts coastline have been designated "no discharge," and all of that area is south of Boston.Barbara Warren of Salem Sound Coastwatch told selectmen that Lynn, Saugus and Swampscott are working on applications to the Massachusetts Office of Coastal Zone Management as well.Harbormaster Charles Dalferro and Harbors and Waters Board Chairman Gary Gregory told the selectmen the Coast Guard and harbormaster will enforce the restriction and there will be fines for violations, but "This will affect less than two dozen boats."The town currently maintains a pump-out station on shore and a pump-out boat. The town plans to apply for a $32,500 grant to build a second pump-out station.Salem Sound Coastwatch surveyed boat owners in the Danvers River, Beverly Harbor and Salem Harbor (Marblehead and Salem). SSC received 871 responses from a total of 4,063 mooring permit holders, or a 21 percent return.Of those respondents, 96 percent were aware that federal law prohibits discharge of untreated sewage from vessels within three miles of the coast, and more than 80 percent were aware that sewage might cause problems at beaches and increase health risks.However, 25 percent did not know of any pump-out facilities in Salem Sound and 58 percent have never used pump-out services, which included 11 percent of the boat owners with holding tanks.