Understanding Boat Toilets: A Guide To Marine Sanitation

Marine toilets, or heads, are an essential part of sailing adventures, but they work quite differently from the toilets we use at home. In this article, we will explore the different types of marine toilets, from manual and electric to chemical and cassette, and how they operate. We will also discuss the dos and don'ts of using a boat toilet, including what not to flush, and how to maintain and empty the waste tank. So, whether you're planning a sailing holiday or simply curious about how boat toilets work, read on to discover the ins and outs of marine sanitation!

Flushing: manual vs electric

Marine toilets, also known as "heads", are an essential part of sailing adventures. While they may appear similar to standard toilets, their operation is quite different due to the unique environment. One of the main differences is in the flushing process. Marine toilets can have either a manual or an electric pump.

Manual Pump

Manual pumps require more effort and attention than electric pumps. To operate a manual pump, you need to move a lever back and forth, which activates a piston that pushes the waste out. This process can be intimidating at first, but with practice, it becomes second nature. It's important to handle manual pumps carefully as they are delicate and can be easily damaged if misused.

Electric Pump

Electric pumps automate the flushing process with the push of a button. Some advanced models even handle everything automatically, similar to the toilets on ships or planes. However, electric toilets tend to be noisy, so if you're sailing at night and want to avoid disturbing others, a manual pump might be a better option.

Flushing Process

Regardless of the pump type, the flushing process in marine toilets is different from standard toilets. When you flush a marine toilet, its contents are pumped out through a hole in the hull, either directly into the sea (direct discharge) or into a holding tank. This direct discharge method is not environmentally friendly and is prohibited by marine sanitation legislation in many countries. Therefore, modern boats are increasingly equipped with holding tanks that store waste, allowing for more environmentally friendly operations.

Environmental Impact

Holding tanks are particularly beneficial when docked at a marina, anchored in a bay, or near protected areas. They usually have a capacity of about 40 litres and are located near the toilet they serve. It's important to empty the holding tank frequently, keep it clean, and dilute the contents with seawater to minimise unpleasant odours.

In summary, while manual and electric pumps offer different levels of convenience, both types of flushing systems on boat toilets differ significantly from those on standard land-based toilets.

What not to flush

Boat toilets, also known as marine toilets or "heads", are quite different from the ones at home. They require more attention and careful handling to avoid clogging and damage. Here's what you should avoid flushing down a boat toilet:

Toilet Paper

Although some modern boats have integrated shredders, it is generally advised not to flush toilet paper. It can cause clogs in the pipes, leading to unpleasant maintenance work. Instead, dispose of toilet paper in separate trash bags or bins provided near the toilet.

Sanitary Products and Other Hygiene Items

Do not flush sanitary towels, tampons, dental floss, or any other feminine hygiene products. These items are not designed to break down in marine sanitation systems and can cause serious blockages. Use the designated trash bins or bags for proper disposal.

Food Scraps and Large Solid Waste

Be cautious with food scraps and avoid flushing them. Large or solid stools can also lead to clogging issues. To prevent this, ensure you consume adequate fibre, fruits, and vegetables, and stay properly hydrated.

Foreign Objects

Avoid flushing any foreign objects such as old parking tickets, hair, or other items that could potentially cause blockages. Keep in mind that the pipes in boat toilets are narrower than those in domestic plumbing.

Chemical Cleaners

Do not use household cleaners to clean the boat toilet. Instead, opt for commercially available septic system cleaners designed specifically for marine sanitation systems.

Remember, the key to maintaining a boat toilet is to be mindful of what goes into it. By following these guidelines, you can help ensure a smooth and trouble-free experience while enjoying your sailing adventures.

Holding tanks

To empty a holding tank, you will need to disconnect the toilet seat from the lower holding tank and transport the tank to an appropriate disposal location, usually at a marina or pump-out station. It is important to keep the tank clean and odour-free by rinsing it with seawater or using septic tank treatment tablets.

The use of holding tanks ensures that waste is disposed of properly and helps to preserve the marine environment. It is crucial to follow good toilet etiquette and only dispose of human waste and toilet paper in the tanks, as other items can cause clogs and require manual unblocking.

Marine sanitation laws

Marine sanitation is an important aspect of sailing adventures, and understanding the laws surrounding it is crucial. Here are some detailed information and instructions regarding marine sanitation laws:

Marine Sanitation Devices (MSDs)

The Clean Water Act (CWA) regulates sewage discharges from vessels in US waters by mandating the use of Marine Sanitation Devices (MSDs). An MSD is defined as "any equipment for installation on board a vessel, designed to receive, retain, treat, or discharge sewage, and any process to treat such sewage." The US Environmental Protection Agency (EPA) and the US Coast Guard jointly regulate MSDs.

Who Needs to Use an MSD?

Section 312 of the CWA requires vessels equipped with installed toilets and operating on US navigable waters, including the three-mile territorial seas, to use operable, US Coast Guard-certified MSDs. Vessels without installed toilets, such as those with "porta-potties," are exempt from this requirement.

Types of MSDs

The US Coast Guard categorizes MSDs into three types:

• Type I MSDs: Flow-through treatment devices using maceration and disinfection, suitable for vessels up to 65 feet in length. They must produce an effluent with no visible floating solids and a low bacterial count.
• Type II MSDs: Flow-through treatment devices that may employ biological treatment and disinfection, suitable for larger vessels. They have more stringent effluent requirements than Type I and can be installed on vessels of any length.
• Type III MSDs: Holding tanks that store sewage without treating it onboard. These are designed to prevent the overboard discharge of sewage and can be installed on vessels of any length.

Sewage Discharge Regulations

It is illegal to discharge raw or untreated sewage within three miles from the shore or within a No-Discharge Zone (NDZ). Sewage must be treated using a US Coast Guard-approved Type I or Type II MSD or stored onboard in a Type III MSD holding tank. Treated and untreated sewage discharges are prohibited in freshwater lakes, reservoirs, rivers without interstate vessel traffic, and NDZs.

Compliance with No-Discharge Zones (NDZs)

When operating in an NDZ, overboard discharge from MSDs is generally prohibited. To secure a flow-through device (Type I or Type II MSD), vessel operators must close the seacock, remove the handle, padlock the seacock, use a non-releasable wire tie, or lock the door to the space enclosing the toilets.

Reporting Violations

Violations of vessel sewage regulations should be reported to the local US Coast Guard office, the National Response Center, and the local marina if appropriate. Discharging raw or untreated sewage inside US waters can result in a civil penalty of up to $2,000 for each violation.

International Conventions

According to international conventions on ecology, discharging faeces into the sea near the coast is discouraged due to its polluting impact on the marine environment and coastal areas. Sailors typically discharge waste tanks further offshore or use pump-out stations at marinas, although this varies by region.

Cleaning and maintenance

To keep your boat toilet in good working order, regular cleaning and maintenance are essential. Here are some detailed instructions to keep things running smoothly:

Emptying the Waste Tank

It is important to empty the waste tank frequently, especially if you are using a holding tank to store waste. This will help to minimise unpleasant odours, which can be more noticeable in hot weather. Most marinas have waste disposal locations where you can empty your waste tank. Ask the harbour master for guidance on waste disposal locations.

Flushing the Tank

To further reduce odours and keep the tank clean, flush the tank with seawater. This will help to dilute its contents. If odours persist, some tanks have a deck fitting that allows you to pour hot water into the tank for a more thorough clean.

Pump-Out Stations

At some marinas, you can use a pump-out station to empty the tank more thoroughly. This is particularly useful if you are unable to completely empty the tank at a standard waste disposal location.

Using the Correct Toilet Paper

To avoid clogs, it is important to use RV-friendly toilet paper that is designed for marine toilets. While some standard toilet paper can be used, it should not be flushed and should be disposed of separately.

Avoiding Clogs

To prevent clogs, do not put anything other than human waste and RV-friendly toilet paper into the disposal tank. This includes dental floss, feminine hygiene products, and other sanitary products. These items should be disposed of in a separate sanitary receptacle or rubbish bin.

Regular Cleaning

Even with proper waste disposal practices, the marine toilet will need to be cleaned regularly. Rinsing the toilet each time you empty the waste tank is ideal, and most dump sites provide a water hose for this purpose.

Using Septic Tank Treatment Tablets

Periodically, you should treat the waste tank with eco-friendly septic tank treatment tablets. These tablets will help to break down solid waste, neutralise odours, and prevent backups and other potential issues. On average, use treatment tablets every 4-5 times you empty the waste tank.

Frequently asked questions