Study Topics
Boats in Action Section Quiz Site Map
Human Waste Disposal
Marine Sanitation Devices (MSDs)

Anyone that spends a day on a boat with a head has the dubious pleasure of using the “onboard facilities.” Whether you are on a 16’ outboard or a 40’ ketch, the "call of nature" is a regular part of our boating experience. So what's the big deal about using the water as a big bathroom?

The primary environmental concern with your sewage is not the urine (which is basically sterile) , but the feces. Human feces contains bacteria, pathogens, and nutrients. The idea behind federal regulations concerning sewage on boats is to keep untreated sewage out of our inland and coastal waters, so we don’t have to swim in it or drink it. Read on for the regulatory details.

Sanitation Regulations

In most inland and coastal waters, boats with installed toilets are required to have a sanitation system on board in order to control pollution. Standards have been set by the Environmental Protection Agency, and regulations have been Issued by the Coast Guard, covering the certification and use of Marine Sanitation Devices. Sanitation systems consist of an installed head (toilet), a waste-treating device (MSD), and/or a holding tank.

As with most Coast Guard Certified equipment, there are different classifications to cover most every
marine application.

Type One MSDs typically discharge treated waste directly overboard.