Composting Toilet & Greywater System

What is greywater?

Greywater is a kind of wastewater.

Wastewater is used water from houses or establishments. It is initially fresh or raw water that goes through a process that mixes it with substances such as soap from washing and bathing, human waste from flushing, and other waste.

A regular house produces wastewater, and there are two kinds of it.

Blackwater is wastewater from toilet plumbing. It carries human waste and is very much contaminated with bacteria and hazardous for humans and the environment.

Then there is used water from all other sources, which is called greywater. To put it simply, it is anything not from the toilet. It includes kitchen and bathroom sinks, baths and showers, and washing machines.

Here is where eco toilets, specifically composting toilets, come in.

What is a composting toilet?

A regular toilet collects poop and pee and then flushes them down. A composting toilet does the same thing. Almost. This is because while a regular flush toilet uses water (in liters!), the composting toilet uses none of that. And because it does not use water to carry the waste to septic tanks or treatment facilities, a composting toilet does not produce wastewater.

Before we understand how it helps the environment on a bigger scale, you might first wonder, how does a composting toilet work? This toilet stores the solids in the composting chamber while separating the liquids through another pipe. Composting chambers use the composting process, where waste is broken down and turned into compost. This is possible with carbon material and a well-maintained chamber. And instead of adding up waste to throw away, compost can be a great natural fertilizer for the soil.

This article about composting toilets shares more info about this.

How do they work together?

A household with a composting toilet can still produce wastewater. This can be a drawback if you’re all eco-friendly for the environment. Unlike blackwater, which is toilet waste, greywater comes from the shower, kitchen, and washer. An advantage of this used water is that it contains fewer contaminants, making it still reusable for the outdoors (such as gardening) and even for regular toilet flushing. This means using less clean water for other needs at home.

Greywater systems help direct and collect used water for other household purposes. It is explained more in this quick guide, which also lists the different types. Greywater systems follow these steps— pretreatment, filter, storage, and then irrigation or where you decide to use it.

The filtering process can use a sand and gravel filter or a surge tank to separate the dirt and sediments from the used water. The surge tank slows the flow, allowing the solid bits to slowly sink first before the cleaner water gets carried on outdoors and into the gardens.

We can see how we can reuse greywater at home, but you cannot do the same for blackwater unless it is first sent to treatment facilities. With that kind of waste, it helps not to produce it in the first place. When you decide to use a composting toilet instead of the regular flush toilet, it will complement the greywater systems water use.

Environmental Benefits

We’re all about conserving water as much as we can. And even with a composting toilet, we still can’t help using water for our other day-to-day activities. Good thing that when following the correct procedure for the greywater systems, we can still reuse around 75% of used water at home. That saves the clean water we usually use by half.

With the global concern about the earth and our environment, we have this chance to be responsible for our choices. With the practice of maintaining composting toilets, we have already reduced our water consumption daily. Adding the greywater systems, what we do in our homes becomes an essential role in responsible and sustainable living. It serves a bigger purpose in boosting the well-being of our environment. We are no more going about our business, pooping and peeing just for it to go to waste. Instead, we make fertilizer out of it and then give it back to the soil. Not a liter of water gets wasted in the process. And when we do use water at home, we are committed to putting it to another use and back to the environment.

How hard is it to maintain

Both composting toilets and greywater systems need regular maintenance. The upkeep efforts will depend on how often it is used and how much goes through them.

These must be considered and regularly checked for a composting toilet to function well for a long time.

  • Carbon materials such as sawdust, coconut fiber, and dried leaves must be placed on the poop to balance the carbon-nitrogen ratio. This balance keeps a suitable environment for the microorganisms that decompose the solid waste.
  • A proper diverting pipe is needed to separate the liquid from the solid waste to keep the compost mix from becoming too wet. The compost in the chamber must remain moist for the microorganisms to thrive.
  • Unwanted elements (such as insects) can enter and compost the mix. Always closing the lid when it’s not being used can keep them out.
  • Since the waste doesn’t go to sewers and septic tanks, the chamber will get full in time and must be emptied every few weeks to a few months, depending on how often it is used.

As for greywater systems, this will depend on the type installed.

  • As much as we try to reuse all the used water in the household, it is crucial to separate water contaminated with some detergents and those from the dishwasher and kitchen sinks that likely have chemicals, salt, and fats. Some of its ingredients can affect filtration and are toxic to plants. Leaving this out from the used water that goes through greywater filtration keeps the stored water free to use in the garden and outdoors.
  • Maintaining a filter ensures small and light materials like hair and other sediments don’t mix with the cleaner water.
  • Using the treated greywater regularly. You cannot store greywater for more than a day because bacteria can grow and contaminate the already cleaned used water.
  • We must be mindful of the temperature that keeps the stored water as clean as possible. Warmth allows bacteria to thrive, so keeping it at a colder temperature is best because the heat allows bacteria to thrive.
  • Like any device and equipment, regular check-ups can help make sure all the parts in the greywater system are working well.

How much does it cost?

Where you live and where you will buy can affect the price. But before putting everything into place, it is best to make sure first all the regulations of the city or state you’re in about installing composting toilets and greywater systems.

In getting greywater systems for your home, knowing what kind works best for you can save up on the cost. There’s already a big difference in how much is spent in retrofitting a greywater system into a home compared to setting it up while the house or space is still being built. It would be best to consider what your treated greywater is for. The level of purity needed for the treatment will matter in the cost. Say, if you’re getting it to water vegetables for eating, you will need to invest in a more advanced treatment system.

A greywater system can be around 4,000 Australian dollars with all the essential treatment features. The cost depends on the quality of the materials for the valves, surge tanks, hoses, filters, and pumps built. There is also that consideration for extra plumbing for houses with many places producing greywater.

The more complex the greywater system, the more money you will need to invest. But even with that, it is helpful to know that better-treated greywater can have more uses at home and in the garden. A complex greywater system cleans used water better to make it close to the clean water we use daily.

Like composting toilets, investing more can be beneficial to the eco-friendly practice. A properly maintained composting toilet with a fully-equipped composting chamber will keep out the problems of smell and compost quality.

Prices of a composting toilet can go from around 1,000 Australian Dollars. Of course, once you’ve installed a composting toilet and a greywater system, you still need to spend on its maintenance. But that shouldn’t be a problem with how much water we are saving and how much we are helping the environment in the long run.

Using greywater systems and composting toilets in our routine saves up on the cost of water and the effects of wasting water. Buying and installing this equipment can initially seem complicated and intimidating with how different it is from a normal one. There are few differences in how we poop, pee, and use water. We still do it every day. But the ecological effect of this change in our household systems is a big move for us and the environment.

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