Study Topics
Boats in Action Section Quiz Site Map
Human Waste Disposal
Pumpout Services

What it all means...

This national symbol is used to show boaters where onshore pumpout services
are located. You’ll need to know this symbol if you use a portable toilet or Type III
MSD (holding tank) on your boat.

Federal law says that untreated sewage (even if it's been dosed with a deodorant product) can NOT be discharged in inland or coastal waters. This means the sewage from a portable toilet or a Type III holding tank can not be discharged unless you are in the ocean more than 3 miles offshore.

Federal law also states that if you have a holding tank with a "Y" valve allowing direct overboard discharge of untreated waste, it must be secured in the closed position while operating in all inland and coastal waters. Using a non-releasable wire tie, padlock, or removing the valve handle is considered adequate securing of the device.

Operating in a federally designated “No Discharge Area” further restricts what sewage you can discharge overboard. In these areas, there is no treated sewage discharge allowed from boats. That means if you have a Type I or II MSD, you are not allowed to discharge it while in those waters. There is a trend towards more local waters being designated as No Discharge Areas, so if you rely on using your Type I or II MSD, check a cruising guide before venturing into new waters.

What about grey water?

Grey water is the water discharging from your sink and shower, while black water is the sewage/water discharging from a toilet. In the United States, there are no federal requirements for the containment of grey water. However, in Canada, and in some inland lakes, there may be additional restrictions. Please check your local cruising guide or with your local state boating agency for more details. Are You In Compliance?

Equipment on Boat Legal? Restrictions and Comments

Installed toilet without MSD


Installed toilet with macerator


USCG regulations require that all installed toilets have an attached MSD. Macerator does not count.

Installed toilet with Type I MSD*

Yes (But not ok in No Discharge Areas)

Ok on boats <65'. Discharge is <1000 per 100 milliliters of fecal coliform bacteria with no visibly identifiable floating solids.

Installed toilet with Type II MSD**

Yes (But not ok in No Discharge Areas)

Ok on any size boat. found on larger boats because of electricity and space requirements. Discharge is <200 per 100 milliliters of fecal coliform bacteria with <150 milligrams of suspended solids per liter.

Installed toilet with Type III MSD**


Keeps waste out of water by using a holding tank. Discharge at onshore pumpout facility or via "Y" valve while more than 3 miles offshore in the ocean.

Portable toilet

Legal on any boat.*

Does not fall under USCG regulations of MSD's.

No installed toilet


Remember No Discharge Area rules.

Note: Some states have additional restrictions.

For example, in Florida, houseboats may only have a Type III MSD or a permanent sewer line to shore. Check on your state's laws.

** Must be USCG certified

* Not legal in the province of Ontario