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It's the Law

Discharge of Sewage and Waste


You are not required to have an installed toilet on your vessel. Many people use portable toilets and dispose of the waste at a public launch that has a pump-out station equipped for portable toilets.

For long outings, equip your vessel with toilet facilities. See Idaho Boat Pump-Out & Sanitation Sites for a list of pump-out and sanitation sites.

If your vessel does have an installed toilet, federal law requires a U.S. Coast Guard–certified marine sanitation device (MSD) that is working properly.

Types of MSDs

Types I and II MSDs treat waste with special chemicals to kill bacteria. If you have a Type I or II MSD, it must have a holding tank for untreated waste and a “Y” valve that must be secured in a closed position while operating in U.S. waters.

Type III MSDs provide no treatment and are either holding tanks or portable toilets. Collected waste should be taken ashore and disposed of in a pump-out station or onshore toilet.

Marine Sanitation Device (MSD)

The "Y" valve must be secured so that waste cannot be discharged into the water.