Why is the discharge of boat sewage overboard a public health and water quality concern?
Boat toilet waste is much more concentrated than domestic sewage. Thus, Vessel sewage contains biological contaminants that can be harmful to humans. The chemicals used to treat vessel sewage can also pose an environmental and health risk. Some potential health hazards include infectious hepatitis, diarrhea, and cholera. A single overboard discharge from a boat toilet or holding tank in a low dilution environment, such as a marina, can be detected for at least one square mile from the discharge point. Sewage acts as a fertilizer in the marine environment, leading to uncontrolled algae growth and subsequent depletion of dissolved oxygen. Low levels of dissolved oxygen can lead to the death of fish and valuable marine plant life. In addition, shellfish can concentrate microorganisms discharged to the Marine environment, thus resulting in possible ingestion of an infectious dose of such microorganisms by those eating the shellfish. Shellfish beds, swimming areas and fishing areas may have
