Poo, ahoy! Composting toilets on boats

Boats, yachts and similar watercraft usually use conventional on-board toilets. Many people resort to mechanical pumping, others swear by the electronic version, and some people use chemicals to combat the hustle and bustle on board. But there is a simple and sustainable alternative: the composting toilet. Find out about old methods and new opportunities in this guide.

What's the story with the on-board toilet?

It is often rumored that on ships and boats the daily business is drained into the waters after rinsing. This is not correct. From a purely legal point of view, the leftovers may not simply be dumped in the cool water. The waters are protected, so going overboard with poop should be avoided as much as possible.
The International Convention for the Prevention of Pollution from Ships (MARPOL) regulates how and where wastewater from ships may be disposed of. For example, waste and sewage may only be disposed of once a minimum distance from the coast has been reached. On inland waters, "wild dumping" of feces is an absolute no-go.

And how is the disposal done?

On public vessels, seawater is used for flushing and pumped to the on-board toilet. Large and small trades are collected in the tanks of the toilet and disposed of in the harbor. There are special facilities for this purpose. Only excrement and toilet paper may be placed in the on-board toilet. In the large ships, a fecal treatment plant is often available. If one is available, it is permitted to discharge the treated excreta into the waters. The solids are filtered and produce sewage sludge. This is dried and compressed. It can then also be disposed of in the harbor.

What is the situation on a private boat or yacht?

With small boats the whole thing looks different. Thus it is to have occurred here already the one or other time that bucketfuls of heaps went over the railing. Especially on inland waters or near the coast, this is neither allowed nor the right thing to do. On the one hand bacteria contaminate the waters, on the other hand nobody wants to cross the path of a foreign sausage while swimming. However, if you want to be on the water for a longer time or anchor in a dreamy bay in the last evening sunshine, you need a toilet on board. This should be firmly anchored so that it cannot become independent. 

What kind of on-board toilets are there?

The mechanical on-board toilet

Mechanical on-board toilets have two simplified functions: Pumping and flushing. There are two switches and a lever for this purpose. To get the business out of sight, the pump-down switch is flipped and the pump lever is operated at the same time. Then the switch is reset and the flush switch is operated. With the flush running, the lever is also operated several times to flush down large and small stores. To empty the toilet bowl, the switch is returned to "pump down" and the lever is again operated several times. Afterwards, the pump lever is locked and the on-board toilet is ready for the next pop. Sounds complicated? It kind of is!

The electric on-board toilet

The electrically operated version of the on-board toilet works on the same principle as its mechanical sister. However, there is no need to operate the pump lever manually. With one switch for pumping and one for flushing, the system is easier to use. 

Special features of on-board toilets

Regardless of whether you rely on manual operation or electronic assistance, flushing with drinking water is recommended for both types of on-board toilet. It is possible to use a seawater pump, but this can cause unpleasant odors. 
If the toilet is flushed with seawater, the connections are located below the waterline. Due to the suction effect, there is always a risk that the toilet will overflow. A gooseneck reduces the risk, but it cannot prevent such a fiasco. If the swell is strong and the boat heels, unpleasant flooding can basically occur. 
Toilet paper can be disposed of in the on-board toilet if it has a shredder. Otherwise, there is a risk that the hoses and pump will become clogged. To eliminate this risk, many collect the paper in a separate container. Similar to diaper pails, these spread their uncharming odeur when you loupe the lid, which you thus close again faster than you opened it.
 
Disposal of the contents of on-board toilets takes place near the shore in the harbor. The wastewater is collected in a holding tank, which is then disposed of at a station in the harbor. Depending on how many water sports enthusiasts have the same idea at the same time, you may have to wait in line here.

The chemical toilet

The chemical toilet is the low-cost and easy-to-install version of the on-board toilet. They are quite compact, so they are mainly used in small boats. However, in heavy seas, this can become a bit of an adventure. To ensure hygiene, chemicals are required. This ensures that the stores are decomposed and can be disposed of in a liquefied form. They are therefore emptied at special disposal stations in ports. Until you get to these, however, you are literally stuck with what you have left behind.

A disadvantage of the chemical toilet is that it can be quite heavy. If it is located deep below deck, carrying the toilet quickly becomes difficult and uncomfortable. That's why it's important to find a remedy. The chemical toilet cassette should be disposed of soon enough, as soon as the opportunity presents itself. In addition, this toilet should be cleaned regularly. This reduces unpleasant odors and ensures general well-being.

The composting toilet and its characteristics

Characteristic of a composting toilet is that you do not need water for flushing and therefore no connection to the sewer system. This makes these toilets the perfect alternative on boats to the environmentally unfriendly chemical toilets. In addition, the sewage system experiences a relief. Composting toilets, which separate solid from liquid, are particularly suitable. This prevents unpleasant odors. Due to these properties, such models are called composting toilets.
Unlike a chemical toilet or a regular toilet, a composting toilet may seem a little strange at first. After all, in ordinary toilets, all business goes into one container and then disposed of, depending on the system. This is not the case with composting toilets. The separating insert of the toilet separates the small business from the big business already when going to the toilet. Urine goes down the drain at the front into a canister, solids and toilet paper go through a large opening at the back into the bucket provided for them. After that, some litter is added to the leftovers to remove the existing moisture from them. The drying process ensures that there are virtually no odors. Suitable as litter are sawdust, small animal litter, coconut fiber, fine bark mulch, Terra Preta, dry coffee grounds or special composting toilet litter with activated carbon, which additionally binds odors.

Also good - the composting toilet does without chemicals

If you want to do something good for the environment, such a composting toilet is best suited for you. The separation function prevents odors from developing and allows you to dispose of solids and liquids independently of each other. This makes the use of chemicals unnecessary.

How do you dispose of the excrement in the composting toilet?

Urine can be disposed of in any normal toilet. If you want to be on the road for a longer period of time, you can use a second canister. You equip the solid waste container with a garbage bag. This way it can be collected cleanly together with the litter and toilet paper. When the bag is full, it is tightly closed and can be disposed of in the normal household waste. The cleaning is very easy. You need nothing more than diluted vinegar or citric acid. Alternatively, you can also use cleaners with effective microorganisms.

The use of composting toilets is absolutely hygienic and comparable to ordinary toilets at home. The disposal of the leftovers is easy and protects the environment. The formation of odors can be reduced to a minimum. In addition, you are absolutely self-sufficient with composting toilets. So you are absolutely independent on boats and yachts. Would you like to know which Trelino® best suits you and your boat? Here you can find all models and variations.