The Law

Clean Water & Boat Sewage

Sewage waste discharged from boats may degrade water quality by introducing disease-causing microorganisms into the marine environment and depressing oxygen levels as the sewage decays. Shellfish beds with a fecal coliform bacteria count of 14 per 100 milliliters of water must be closed. Waters with a count of 200 fecal coliform bacteria per 100 milliliters are closed to swimming and other primary contact recreation activities, which hurts tourism and deteriorates the quality of life for all of us. 1 gallon of sewage from a boat has as much bacteria as 10,000 gallons of treated municipal wastewater.

What Do The Laws Say?

Federal law prohibits the discharge of untreated sewage from vessels within navigable waters of the United States, which include territorial seas within three miles of shore and most bays and estuaries. Boats with Type I and II marine sanitation devices (MSD’s) may discharge treated effluent in coastal waters unless they are in a no discharge area.

No-Discharge Areas


Under the Clean Water Act, states may petition the EPA to designate no-discharge areas where discharge of all sewage, treated or not, is prohibited. The EPA will not approve a no-discharge area unless there are adequate pump-out facilities available to mariners. Type III MSD’s are the only type that can be used legally in a no-discharge area, and must be emptied at a pump-out station. Clear Lake is currently the only no-discharge area on the Texas coast.

Marine Sanitation Devices

The Federal Clean Water Act requires that all boats with an installed head have one of three types of Coast Guard approved marine sanitation devices (MSD’s) attached to the toilet. Failure to comply can result in a $2,000 fine. Type I and II MSD’s are flow-through systems that treat the sewage using chemical, electrical and/or incineration methods before discharging the waste overboard; i.e., Lectra-San or Microphor. A macerator pump is not an MSD. Type III MSD’s are holding tanks that store sewage on the boat. The waste is not treated in a Type III device, even if odor-reducing chemicals are added. It is illegal to discharge or empty the contents of your boat’s holding tank in U.S. territorial water ( within a three-mile limit). Some boats are equipped with a “Y” -valve that allows for the direct discharge of raw sewage. This valve can only be used outside the three-mile limit. Coast Guard regulations require that the “Y”-valve must be secured in the closed position (by padlock, non-resealable tie, removal of handle or other physical barrier) when the boat is within three miles of shore. Boaters can be fined for non-compliance. If you use a portable toilet, remember it is illegal to dump it overboard. Use shore side facilities to empty it. SPECIAL NOTE: Waste treated by Type I and II MSD’s is unhealthy for marine waters because (1) chemical treatment often sanitizes only the outer surfaces of waste clumps, (2) chemicals routinely used in MSD’s are harmful to sea life and water quality (chlorine, formaldehyde, formaline, phenol derivatives, ammonia compounds), (3) poorly maintained MSD’s may not treat effluent to the prescribed standards, and (4) even treated sewage contributes nutrients and lowers dissolved oxygen levels in water, lowering water quality for marine life.

How Does This Affect Me?

Complying with vessel sewage discharge laws and regulations, and using pump-out facilities are necessary to protect water quality, public health and the marine environment. Mariners are encouraged to get ready for no-discharge areas all along the Texas Gulf Coast by retrofitting their boats with holding tanks. This may not seem fair to those who have done the “right thing” earlier by installing Type I or II MSD’s, but the national movement toward designation of no-discharge areas is changing the rules.

If you have a Type I or II MSD, don’t discharge it while in confined shallow waters, marinas, shellfish beds or contact recreation areas. Use shore side restrooms before going out to sea and when docked or moored in the harbor, and dispose of port-a-potty waste properly on shore.

Certify Your Device

Texas has a program to certify your marine sanitation device.

If you operate a boat on Clear Lake which is 26-feet or longer and have permanent sleeping quarters on board, your boat must have a marine sanitation device and be certified. If your boat is less than 26-feet but has a marine sanitation device, it also must be certified. To apply for your decal, please complete TCEQ-0117. Owners will receive a decal which must be displayed on the hull of their boat after submitting their application.

The Texas Parks and Wildlife Department is now enforcing the Texas Clean Water Act on Lake Texoma and is inspecting boats for compliance. In the interest of public health, they have ruled that by December 31st 2010 all of the vessels in the Clear Lake/Galveston Bay area must have their marine sanitation device certified.

Clean Vessel Act

Wildlife & Sport Fish Restoration Program