In an earlier post regarding our water management strategies for our off-grid permaculture property in Baja California Sur, Mexico, I mentioned that using a dry composting toilet system would be a great way to save about 30 000 litres of water per person each year. It is a great solution to reduce water consumption, especially in our dry desert climate.

In this post I would like to discuss another option for those who do decide to keep using a more conventional flushing toilet. This would be a vermicomposting toilet.

Why are we considering a flushing toilet if the water consumption is so incredibly high?
In our ‘modern’ society, flushing toilets have become the norm, and it is hard for some people to change to a dry composting toilet. They are afraid it would smell, or they do not want to deal with the regular maintenance they require. Many people even falsely believe that these systems are not hygienic.
Although we do not agree with these opinions and ideas, it is still the reality that many people are conditioned to think this way, and therefore will not give up on their beloved flushing toilets.

As we are planning to develop our permaculture property as a demonstration site, we would like to be inclusive to everyone, and as a result we would like to demonstrate systems that can be implemented and which improve on the current standards.

Another reason why we are considering a flushing system is that we intend to develop extensive plant systems and gardens on our property. These will need watering at certain stages of their establishment. Therefore, if we can use the same water to accomplish two tasks (or more), then it is a possible to have ‘the best of both worlds’.

So how do we combine the flushing of the toilet, the resulting black water, and watering the garden? How do we treat the water in such a way that it is safe to use, and healthy for us and the environment we live in?
We are choosing a vermicomposting system to do this task.

Why are we opting for a vermicomposting system, and how does it work?
The vermicomposting system works in a similar way to a traditional septic system. The plumbing and toilets inside the house are all conventional, obviously using the systems that consume the least amount of water.
The difference lies in the receptive tank, where instead of an anaerobic septic system, we install a vermicomposting system. This system breaks down the solid wastes aerobically, with the help of a complex and extremely biologically active ecosystem contained in a tank. This happens much faster than in any anaerobic system.
From the tank, the water then passes through a normal biological reed bed filter, before being used to water certain areas of the garden.

A system that is correctly sized according to the amount of people who regularly use it, it will be completely self-regulating, as the composting worms adjust their populations quickly according to the amount of material that needs to be processed. As a result, the tanks will never need to be pumped out, as you do not have a buildup of solid materials. In a traditional septic system, you would need to pump out solid wastes every few years, and then that waste requires further treatment and disposal off-site.
The vermicomposting system has no access solid waste products that need to be taken care of.

The second benefit of this system is that the water that exists the worm tank is much cleaner than that released by a traditional septic system, thanks to the higher efficiency of aerobic composition. Not only is it cleaner, but it now contains a much higher content of microorganisms, worm eggs, and nutrients, etc. All of these enrich the soils wherever the water is used, which in return results in happy and health plants, and a much healthier ecosystem in general.

A third benefit of a vermicomposting system is the ease, and relatively low cost, of installation. They are commercially available in some parts of the world. They can however be self-built fairly easily, with simple components that can be sourced locally in most places.

The maintenance of a vermicomposting system consists of adding a few carbon rich materials every couple of months to keep the nitrogen/carbon ratios balanced. Thats about all it takes.

To find out more about these vermicomposting system, and for instructions on how to build them, visit VermicompostingToilets.com.

In Conclusion:

The composting toilet is a great solution, and at the top of the list of any sustainability comparison. I am a big advocate for them, and for contexts where the water is not available or where there is no need or desire for irrigated plant systems, I would suggest to keep it simple and responsible by using a dry composting system.

Due to the reasons I mentioned earlier, we will be building both, the dry composting toilet, and the vermicomposting system for a flushing toilet.

With the right design, this system will be completely passive, working entirely with gravity (no additional energy inputs), and fully automatic.
Each time you use the loo, you’re actually watering the garden and feeding the soil.

By doing this, we achieve multiple functions without using any additional resources, time or effort. This is only achieved by good design, stacking functions and working with simple, yet complex, natural systems. Nature has done this job since the beginning of time, and will keep doing it forever, effectively, and for free.

Thank you for your time, and I do hope you found this post helpful and informative.
Again, for more information regarding these systems, check out VermicompostingToilets.com

For any questions or observations, do leave a comment below.
Until next time.