Toilets drain sewage

Outdoor & Camping Magazine

On-board toilets have one thing in common: They are primitive, cramped, uncomfortable and usually smell pretty musty. But: when things get really urgent on tour, the best toilet is still the closest one can be reached. We dare to take a look into the world of on-board toilets of the most diverse means of transport - from ship to train to airplane - and clear up the most persistent latrine rumors about what happens when a man or woman press the flush.

The myth of the ship toilet - disposal in the sea?

Ship toilets are preceded by the myth that human metabolic products flow straight into the sea after they have been flushed. After all, the sea is an ecosystem that cleans itself anyway. But is it really true that ships and steamers drag all excretions behind them as a brown carpet?

No, toilet contents on board ships must not simply be conveniently disposed of in the sea (source). The top priority in the maritime space today is Water protection: More and more seas are now under environmental or nature protection and do not allow the feces to be discharged into the blue water world.

Fact: What is really happening on board?

Public ships and ferries

On-board toilets usually flush with sea water, which is pumped up from the sea. The wastewater is then collected in tanks and only emptied in ports, where it is treated in appropriate systems. In general, only metabolic products and toilet paper go into the toilet! Modern and mostly large ships have their own sewage treatment and sewage treatment plants. Only then - in a clean state - may the excretions, which are now de facto no longer present, be returned to the water. The solids filtered out, the so-called "sewage sludge", is ideally dried and pressed and disposed of in the next port (source).

Private boat toilets

In private, bathing on the high seas is often used as a toilet.

On small sailing boats or similar things are very different: According to voices in some sailing forums, it is common practice among private boat owners to go to the toilet and give the fish a bit of food with their faeces during a bath. If that is not for you and you also want to do without going to the public toilet at the port, it is best to build your own toilet. However, you should be aware here: anything that is not fixed will fly at some point in rough seas. It is therefore imperative that you find out in advance how you can best install your toilet.

A chemical toilet is definitely the cheapest and most practical choice to create your own quiet place on board. A mobile toilet is a hygienic alternative, especially for small sailing boats whose space is limited. So using the toilet only becomes adventurous when the sea is too rough. If you use the right sanitary fluid - that is, one that is environmentally friendly like Ensan Green - you can even dispose of the wastewater directly in the sewer system and do not have to go to designated disposal points. Read more about this and about saving water here.

Tip: Depending on where you have placed your chemical toilet on board: Note the weight when the tank is full. If it is far below deck, it is often difficult to carry the completely full toilet upstairs. Therefore, it is better to empty the tank in good time when you have the opportunity. Also the regular cleaning of the toilet is recommended. This allows the odor pollution below deck to be extremely reduced. Here it is advisable to flush the tank with citric acid or special agents.

The myth of the railroad toilet - disposal on the tracks?

Defecation at the locus on rolling wheels - and the excretions are gone. No rinsing necessary, no odor! What is the truth of the myth that the feces - similar to an outhouse - come from the quiet part of the train directly on the route fall down

In rail vehicles it was actually the rule until a few years ago: Gravity made flushing easy and excretions fell on the spot through the wagon directly onto the tracks. In 2004 around 3000 German wagons were still in operation with this type of sewage disposal system (source). These so-called downpipe toilets even allowed through the toilet bowl a look at the train tracks! You have never been so close to the disposal point for your excrement. That was also the reason why there is usually a sign on train toilets that says "Please do not use the toilet when you are in train stations" to find - and above all very justified - was.

This myth persists because not all vehicles with such a disposal system have so far been withdrawn from circulation. From time to time there are still wagons or foreign trains entering Germany that have an open disposal facility.

Fact: How is it actually today?

In modern trains today that is closed toilet system common. The water including the faeces is pumped out by means of a negative pressure. The feces are then collected in containers that are vacuumed out when the trains are cleaned. Unless you're traveling with a rickety steam locomotive from the turn of the century, you can usually use the toilet without restrictions today - even if you're at the train station. (Source)

The myth of the aircraft toilet - blue ice: emptying it in the air?

Again and again there are reports of blue "ice bombs" coming from the air and breaking through houses or causing other damage (source): A legend stuck in the minds of many inhabitants of this earth says that lumps of feces are thrown from the aircraft toilets from time to time frozen in the atmosphere (source)! What is it about the story?

However, this myth is only partially true! Because what is flushed down in the toilet does not always end up in the clouds. And no, the feces are not deliberately dropped in blocks. The “blue ice” phenomenon is still a fact: blue lumps of ice occur when the outlet valve on the toilet tank leaks or when a solid is trapped. Then toilet sewage comes out along with the blue disinfectant and freezes on the outside of the aircraft. This video (from approx. 1:00 min) shows and simulates in an experiment how this “blue ice” forms. During the approach to landing and the increasing warming of the outside temperature, the lumps then loosen and fall off.

Fact: What really happens when a plane is flushed?

It will be similar to rail and ship Sewage collected in a tank and only emptied after landing. Only the hand washing water is released directly from the plane, but atomized so finely that no dangerous blocks can form. (Source)

However, since the risk of the potential formation of "blue ice" is very high, a new type of toilet has been installed in aircraft that works with much less fluid: there is no flushing of water like on the ground in the aircraft for reasons of weight. James Kemper applied for a patent in 1975 for the vacuum toilet, which was also used for airplanes from 1982. This works like a vacuum cleaner - the contents of the toilet bowl are sucked in with negative pressure. Advantageous in the aircraft: The air pressure outside the aircraft is much lower than in the cabin. This means that only little water is required to clean the toilet bowl and, by the way, it is also impossible to overflow or clog the toilet (source). Then it will hold tight until the next landing.


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