MARINE SANITATION DEVICES
(Marine Toilets) USA only
A guide to Marine Sanitation Devices
for recreational boat builders.
The following is mostly mine but has
been contributed to by Peggie Hall, a specialist in Marine
Sanitation Devices. Peggie has kindly corrected my
Author "Get Rid of Boat Odors - A Guide To Marine
Sanitation Systems and Other Sources of Aggravation and Odor"
Peggie can be found on many other on-line boating sources such as:
Community on MSDs
There is no law in the USA that says you have to
have a toilet on a boat, except of course the law of nature, or maybe
your wife; but if you do have a toilet there are laws regulating what
kinds of toilet systems you must have.
Back in the 1970s Congress (see
How Laws Are Made) directed the Environmental Protection Agency to
write regulations for toilets on boats. At the time this seemed to
many people in the boating industry to be a bit of overkill considering
how much impact a boat has on clean water as compared to a city like New
York or Los Angeles, but the regulation came to be anyway. Of course the
EPA was not the agency that would have to enforce these rules. That fell
to the Coast Guard who had to write regulation for certifying Marine
Sanitation Devices and who reluctantly began educating boat
manufacturers and owners concerning requirements.
Basically it works this way. If you have a boat
under 65 feet in length and you have a toilet on board it must be a
portable device, or connected to a certified Type I or Type II device,
or a Type III (a holding tank)
So what's the difference? The portable device is
that you can buy at any camping, RV, outdoor, or even hardware store.
They usually hold around five gallons and will last a day or two
depending on how many people use it, and you take it home and dump it in
your bathroom toilet. You cannot dump them overboard. If you do, and you
get caught, you will receive a hefty fine. They are commonly used on
small day cruisers, overnighters, cuddy cabins, etc.
A Type I is a device connected to a permanently installed toilet
that treats the raw sewage until it is relatively clean and pumps it
into the surrounding water. These are found on boats that do a lot of
offshore cruising. The reality is that many areas of the USA are no
discharge zones ( see link below to no-discharge zones) and so you can
not discharge any waste, treated or otherwise. So the Type I becomes an
option only if you do most of your boating in an area the allows
discharge, or you are in international waters.
type II is similar to a Type I but is designed to deal with much
larger capacities of sewage. The Type II output, the effluent, is
treated to a much higher level than a Type I. Typically Type II
devices are found on much larger yachts and commercial vessels. On
a boat that is 65 feet in length or more you must have a certified Type
II device or a Type III system. Again a Type III is a holding tank
and many larger boats, and even ships, that could use a TYPE II system
have holding tanks instead, and hook up to the local sewer system when
A type III is a permanently installed toilet
connected to a holding tank that retains the sewage. When you return to
the marina it is pumped into the local sewer system at a pump out
station. This is the most common system and most boats sold in
USA, that have toilets, have a holding tank. The reality of this
situation is that there is a serious lack of pump out stations. Many
times the stations do not work, and marinas really do not want the
expense of maintaining them.
How do you know if a device is a Type I or II
device? MSDs have to be
US Coast Guard Certified. This means that they have to meet the
requirements, and the manufacturer has to submit a request for
certification to the Coast Guard. The Coast Guard has the device tested
for compliance. If it passes, they send a letter of certification to the
device manufacturer. The manufacturer then must attach a label to each
device. There should be a certification label somewhere on the device.
If it doesn't have a label, assume it is not a certified device. A type
III system is not required to be certified by the U. S. Coast Guard, and
may have a label but is not required to have one.
Image showing the symbol for a pump out site. To
find pump out facilities look for this symbol.
Type I MSD: A flow-through discharge device
that, under the test conditions described in 33 CFR 159.121,
produces effluent having a fecal coliform bacteria count no greater
than 1000/100 milliliters, and no visible floating solids. A Type I
MSD is commonly a physical / chemical type (macerator /
Type II MSD:A flow-through discharge device the,
under the test conditions described in 33 CFR 159.121, produces effluent
having a fecal coliform bacteria count no greater than 200/100
milliliters, and suspended solids no greater than 150 milligrams/liter.
A Type II MSD is commonly a biological (aerobic digestion) plant, but
several physical / chemical plants are certified as Type II MSDs.
Type III MSD: A device designed to prevent the
overboard discharge of treated or untreated sewage, or any waste derived
from sewage. Most Type IIIs are holding tanks, but there are also vacuum
collection systems, incineration systems, recirculation systems, and a
Portable Toilets: portable toilets are not
defined in the law. They are simply toilets you can pick up and carry
off the boat. They are not permanently installed on the boat.
Permanently installed is defined in many standards as meaning that tools
must be used to remove the device.
In addition to the above, some really large
vessels have incinerators to dispose of waste.
Regulations and links to the EPA.
The Marine Sanitation Device Regulations for Recreational Boats a
List of No Discharge Zones
Cornell Law School, The US Code on MSDs
Justia.com Code Of Fed Regs on Marine
Sanitation Device Standard
Some Coast Guard And Law Enforcement Policies.
If you have a Type I or II MSD and are in a
No Discharge Zone, the device must be locked so it cannot be
accidentally or deliberately discharged. This means you must
have some sort of locking device on the through hull valve to keep it in
the closed position. Any lock will do. With some law enforcement
agencies simply locking the door to the head will do but that is the
rare case. Most look for a lock on the valve that allows it to discharge
into the water, or removal of the valve handle. However, some boats have
a combination of two or more switches that must all be pressed at the
same time to activate the pump. The Coast Guard Office Of Boating
Safety has said this is legal on recreational boats (see
USCG letter to US Marine). For more
See 33 CFR 159.7 for Acceptable Ways to Secure a System
Here is an excerpt from Florida's boating
"Under federal law, if your boat has a valve
allowing direct overboard discharge of untreated waste, it must be
closed while operating in all inland and coastal waters. It is suggested
you use a non-releasable wire tie, lock, or remove the valve handle to
secure the device. When you are more than 3 miles offshore in the ocean,
the valve may be open allowing direct discharge overboard.
A valve may also be found on boats having both a
Type I or II and a holding tank. This gives the boater an option to
discharge treated waste overboard or to contain it for pump out later.
In certain waters, discharge of all sewage (whether Type I, II or III)
Many boats with a holding tank, have a Y valve
installed which allows the tank to be pumped out at a pump out station,
or discharged directly overboard.
Inside US waters this valve must be locked!
Beware; many people think that all they have to do is go three miles
offshore and they can dump the tank. Under Federal
regulations this is true, but some coastal states, such as Rhode Island,
have passed laws extending this distance. In Rhode Island it is
Almost all inland lakes and rivers are no
discharge zones. Here I need to explain what this means. There are
navigable waters and non-navigable waters. These are legal terms used to
divide waters into those under Federal and State laws, and those that
are controlled solely by the state or local authorities. For example,
The Hudson River up to a point north of Albany NY, is a navigable
waterway and is under both Federal and State laws. Beyond that
point it is non-navigable and controlled solely by the state. Clear Lake
in California is sole state (or non-navigable water), while Lake Tahoe
is a navigable waterway. You need to ask the local authorities or
your state Boating Law Administrator (see NASBLA ) about the waters you
plan to use. The best plan is to assumme it is no-discharge until told
otherwise by competent authority. So when I say inland lakes and rivers
I am speaking of non-navigable waters. This does not mean they can not
be used by boats.
All of the waters of the state of Rhode Island
are a No Discharge Zone.
I repeat, never assume an area is a discharge
zone. Always assume it is a no discharge zone until you are informed
otherwise by competent authority.
For Boat Builders:
Recreational boat regulations and commercial
vessel regulations are enforced in separate ways. For recreational
boats, the boat builder has the responsibility to insure that the boat
meets the regulations that apply. The Coast Guard does not
routinely inspect recreational boats at the factory. You may be
visited by a representative (a contract employee) of the Coast Guard who
will help you to comply with the laws. But it is your responsibility to
certify that your boats comply with the law.
Many commercial vessels, especially passenger
carrying vessels that carry more than six passengers, are inspected by
the Coast Guard. You must submit plans, have them approved, and
undergo routine inspections during construction, and a final inspection.
All this is because it is the Coast Guard's responsibility to certify
these boats. There may be additional requirements for the marine
sanitation systems on commercial vessels. You should contact the
Coast Guard Marine
Safety Center or the Marine Safety Office in your area about this
before starting construction.
Links to Information on Marine Sanitation Devices
BoatUS on MSDs
Links to state laws on MSds
National Assoc of State Boating Law Administrators Reference Guide to
State boating Laws
Boating Basics On Line