Type 3 MSD are appropriate for what length of vessel

It is illegal to discharge any treated or untreated sewage into the waters of Nevada. For the health of Nevada waters, vessels with onboard toilets should be equipped with a holding tank, which must be discharged at pump-out stations or onshore toilets.

Vessels with onboard toilet facilities must be equipped with a working US Coast Guard-approved marine sanitation device (MSD).

Vessels up to and including 65 feet in length must be equipped with a Type I, II, or III MSD. Vessels over 65 feet must have a Type II or III MSD. Type I and II MSDs must display a certification label affixed by the manufacturer.

Although “Y” valves are permitted on Nevada waters, it must be secured during operation to prevent the discharge of untreated sewage. Vessels with a Type II MSD must ensure that all pathways for overboard discharge are blocked to prevent any discharge (accidental or intentional) into Nevada waters show the onboard sewage lines ben disconnected or blocked.

It is illegal to dump garbage and plastics into any federally controlled or state waters. Litter can kill birds, fish and marine mammals.

If on federal waters, you must display a 4” x 9” placard on any vessel 26 ft. or longer which notifies passengers and crew about discharge restrictions.

Discharge of oil and other hazardous substances:

• It is illegal to discharge oil or hazardous substances.
• It is illegal to dump oil into bilge of the vessel without means of proper disposal.
• You must discharge oil waste to a reception facility.
• On recreational vessels, a bucket or bailer is adequate.

Littering

It is unlawful to litter in state waters. Litter must be contained until it can be disposed of properly onshore.

Type I is a an on-board treatment device using a physical/chemical based system that relies on maceration and chlorination. After treatment the treated waste can be discharged.

Type II is also an on-board treatment device that uses biological or aerobic digestion based system. After treatment the waste can be discharged. Type II systems are more often seen on large commercial vessels than recreational boats.

Type III is a holding tank or similar device that prevents the overboard discharge of treated or untreated sewage.

• Use enzyme deodorizers for holding tanks and portable toilets.
• Pump out before you haul your boat for the winter.
• Know where your closest pumpout stations are located, and height or draft restrictions, seasonal closures and hours of operation.
• Consider using a pumpout boat service if one is offered in your area to make pumping out more convenient.

Written by Joshua Thibodeaux | Nov 10, 2020 4:30:00 PM

When you’re crafting, purchasing, or maintaining your vessel, it can be easy to get caught up in the exciting specifics of boat care: the equipment you use to perform daily tasks, the engines and motors your boat needs, and other aesthetic or performance upgrades.

Other systems, such as your vessel’s marine sanitation device (MSD), can often go unnoticed. However, your MSD is crucial to the enjoyable, safe function of your boat. Just imagine what would happen if you didn’t have a properly working sewage treatment system. The resulting smells, sights, and gross sludge would be unpleasant, to say the least. 

Just as there are a wide variety of vessels and offshore rigs, there are different types of marine sanitation devices that suit various types of boats. Having the wrong MSD might seem like a trivial matter, but that’s not the case. Having the wrong MSD can result in:

- Overloading your system (leading to smelly, unsafe conditions)- Coast Guard fines- Frustrating and time-consuming maintenance projects

- High replacement costs

Fortunately, it’s relatively simple to find out which type of MSD would best suit your vessel. In this blog post, we’ll cover the different types of marine sanitation devices you’ll see.

The Different Types of Marine Sanitation Devices: What You Need to Know

There are three different types of marine sanitation devices, according to designations set by the U.S. Coast Guard. 

Type I 

Type I marine sanitation devices consist of an onboard treatment device that the sewage you generate can flow through. As the sewage flows through, it gets treated so that you can safely discharge the byproduct off your vessel. 

This type of marine sanitation device takes a physical approach to treating sewage. This means that a Type I MSD pulverizes and macerates all sewage it pipes in. After that, the resulting mass is disinfected with specialized chlorine tablets. These tablets work to neutralize the sewage, reducing the levels of harmful bacteria it hosts down to safe (and Coast Guard approved) limits. 

In some cases, a Type I marine sanitation device might use electrodes to speed up and enhance the disinfection process.

Once the sewage mass is safe, a Type I marine sanitation device will discharge it from your vessel (as long as you’re in an area in which that is an accepted practice). Typically, you’ll see Type I MSDs on smaller recreational boats—ones that are 65 feet in length or smaller. 

For larger vessels, we turn to another class of device. 

Type II

Type II marine sanitation devices are also flow-through devices: Sewage is deposited in one end of the sewage treatment system, piped through, treated, and then discharged off your vessel. This type of system is nice because you don’t have to hold sewage sludge on your vessel for a long period of time. 

Type II MSDs differ from their Type I counterparts in the way they treat sewage. Whereas Type I MSDs take a physical approach to treatment, Type II MSDs rely on biological or aerobic digestion of the waste. Through the use of oxygen-dependent bacteria, the waste is broken down and then treated with a disinfectant. 

Wondering what sets this type of device apart from Type I devices? Bacteria-enabled biological treatment often produces lower bacterial levels than Type I physical treatment—which makes it easier to meet Coast Guard standards for safe discharge, and less likely that you’ll face fines. These MSDs are common on larger commercial boats and production platforms because they’re efficient at what they do. 

Type III 

Type III marine sanitation devices are simpler than the previous types. These MSDs simply consist of a holding tank, which prevents the overboard discharge of untreated sewage. Because they’re less complex, but also less effective at treating waste, these MSDs are usually appropriate only for smaller recreational boats.

Need Help Determining Which Type of MSD Is Best for You? 

When you’re choosing an MSD for your vessel, you need to make sure that you’re making the right decision. Doing otherwise could lead to steep fines and excessive maintenance before ultimately forcing you to replace your system. Save yourself that trouble and pick the right MSD for your vessel the first time around. 

If you need any assistance with maintenance for your sewage or water treatment systems, H2O LLC is a knowledgeable, accessible, and friendly resource for your questions, as well as any support and maintenance you need. To make choosing the ideal marine sanitation device easy, check out H2O LLC’s easy-to-use online calculator.

Signs like this one are posted at pump-out stations.

State law prohibits vessels from discharging any sewage, treated or untreated, into fresh waters of Virginia. If you have a recreational vehicle with installed toilet facilities, it must have an operable marine sanitation device (MSD) on board.

There are three types of MSDs.

• Types I and II MSDs are usually found on large vessels. Waste is treated with special chemicals to kill bacteria before the waste is discharged. Types I and II MSDs with Y valves that would direct the waste overboard must be secured so that the valve cannot be opened. This can be done by placing a lock or non-reusable seal on the Y valve or by taking the handle off the Y valve.
• 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.

Vessels 65 feet or less in length may use a Type I, II, or III MSD. Vessels more than 65 feet in length must install a Type II or III MSD.

All installed devices must be USCG–certified.

Page 2

The Act to Prevent Pollution from Ships places limitations on the discharge of garbage from vessels. It is illegal to dump refuse, garbage, or plastics into any state or federally controlled waters. Many forms of litter can kill birds, fish, and marine mammals.

• You must store trash in a container while on board and place it in a proper receptacle after returning to shore.
• If boating on federally controlled waters and your vessel is 26 feet or longer, you must display a Garbage Disposal Placard in a prominent location. The Garbage Disposal Placard is a durable sign that is at least 4 × 9 inches and notifies passengers and crew about discharge restrictions.

Page 3

If your boat discharges oil or hazardous substances in the water, notify the National Response Center by calling 1-800-424-8802. Also, notify the Virginia Department of Health by calling 1-804-864-7468.

Page 4

If boating on federally controlled waters and your vessel is 26 feet or longer, you must display a 5 × 8-inch placard made of durable material, fixed in a conspicuous place in the machinery spaces or at the bilge pump control station, stating the following:

The Federal Water Pollution Control Act prohibits the discharge of oil or oily waste upon or into any navigable waters of the U.S. The prohibition includes any discharge which causes a film or discoloration of the surface of the water or causes a sludge or emulsion beneath the surface of the water. Violators are subject to substantial civil and/or criminal sanctions including fines and imprisonment.

Oil Discharge Placard: A 5 × 8-inch sign that states the law pertaining to oil discharge

Page 5

Oceangoing vessels that are 40 feet or more in length with cooking and sleeping facilities must have a written Waste Management Plan.

• The captain of the vessel is responsible for implementing the plan.
• The Waste Management Plan, identifying the vessel’s name and home port, should be posted and should include directives to all persons on board about:
  • Discharging sewage and hazardous substances
  • Discharging garbage and other food waste
  • Disposing of plastics, bottles, and cans
  • Reading applicable placards for additional information
  • Advising the captain in case of oily discharges or diesel spills