Our next Water File addresses the issue of sanitation. Many people in drought-affected areas are worried about what will happen when we don’t have enough water to flush toilets. There are alternative dry sanitation solutions you can start looking at now.
1. After Day Zero will I still be able to flush my toilet with rain water or grey water?
You should be able to do so as long as the sewerage systems are still functional. It would be wise to use as little of your precious daily allocation of drinking water for flushing so it is worth considering alternative dry options.
2. Why can’t I just flush with seawater?
Flushing with seawater in the metropolitan area is not an option as it will increase salt in the wastewater treatment plants. If the salinity levels get too high, the microbes which treat the sewage can’t survive and the treatment plants will stop working. The same principle applies to septic tank systems which rely on microbes to decompose the sewage.
Suburbs on the Atlantic Seaboard (Green Point, Sea Point, Camps Bay to Hout Bay) discharge sewage out to sea via a pipeline. Under
emergency conditions you can flush with sea water in these areas.
3. Will the sewerage systems still work after Day Zero?
The City has indicated that the sewerage systems will continue to work after Day Zero. They intend to flush the system at appropriate points to keep the sewage moving. The City engineers are working at ensuring the system continues to function to protect the health of the public as well as the infrastructure.
4. What is more dangerous, urine or faeces?
Urine is essentially sterile, which means it is free of bacteria. If you can urinate in your garden on to soil, it will be absorbed and not present health problems, providing the volumes aren’t too high. Spread it around so it doesn’t get concentrated and smell.
Faeces present a health hazard as they contain disease-carrying bacteria and microbes. Our waterborne sanitation system has been designed to safely remove poo and pee and ensure we don’t come into contact with it. Good sanitation, combined with hand-washing, dramatically reduces the risk of disease.
5. So what is the simplest
solution for Day Zero?
Many people are looking into dry sanitation. The easiest option is a dry compost toilet. This is a bucket housed in a box to support your weight with a toilet seat of your choice and organic material to cover the poo. This can be sawdust or decomposed compost (lots of good bugs). If you use a dry compost system, it’s important to keep your face clear when handling the
buckets and use kitchen gloves you can clean and reuse for the task.
6. How does a dry toilet work?
The ideal is to separate the pee and the poo as much as possible, because if the mixture is too wet, it hampers decomposition. The aim is to keep the poo bucket, which is the highest risk, from filling up too quickly.
One person produces about 1 to 1½ litres of urine a day, which can be disposed of in a green space or in your compost heap.
For people in high rises, the urine can still go in the conventional toilet but dispose of the paper separately. There are products that mask the smell. The poo has to be properly managed to avoid diseases and can be converted into “humanure” (compost). There are many websites on how to construct your own compost loo and how to safely process the waste.
7. Can a dry toilet be used in
a flat without a garden?
Yes, using a bucket system with cover material should prevent it from smelling. Separating out urine is more important in this case. High rises and high-density areas could collaborate to get bulk cover material and compost safely or arrange bulk collection of the material to get composted elsewhere.
Ideally you should be talking to your body corporate about alternative sanitation systems. This could range from sourcing an alternate supply of grey water to flush the toilets, installing a commercial dry toilet system or chemical toilets in the grounds of your building and also advising people on how to minimise blockages by putting toilet paper into a separate bin.
8. What are the features of
a good compost toilet system?
It should not be too wet because then it rots. If it’s too dry it doesn’t compost. It shouldn’t be soggy but have the consistency of good moist soil. You should use a 25-litre bucket with a lid as this is the easiest to carry, and won’t get too heavy. Smell management is done with dry organic material such as sawdust.
9. How do I know if a dry
toilet is working properly?
A dry (bucket) toilet works properly if your material doesn’t leak out of the container/bucket, if you can pick up the container comfortably, and if the container can be closed. A composting toilet works well if it doesn’t smell. If it smells of ammonia, add more organic material. If it rots, there is too much liquid.
10. What other alternatives are there?
Pit latrines: Many people will probably be thinking of the old “long drop” or pit latrine system often found in rural areas. Pit latrines are deep pits in the ground used to collect poo - but they can be smelly and difficult to maintain depending on the geology of the soil. Pit latrines are also problematic in urban areas as they can contaminate the groundwater supply and bring health risks such as worms. It’s advisable to take deworming tablets every six months.
Commercial composting toilets: Another option is to invest in a commercial composting toilet system that uses the natural process of decomposition to break down human waste, yet it is self-contained. There are a number of commercial self-contained dry toilets available in South Africa but these are not always suitable for small dwellings. You would need to research the suitability of each for your needs and reach out to the local authority to see if they might install these in communal spaces. Some are already in use in public areas such as on the top of Signal Hill and in CapeNature rest camps.
Chemical toilets: Chemical toilets are often used by caravanners or at music festivals. These, however, will also need to be serviced so be sure to establish if that is feasible.
DAY ZERO PREP
* Work out what is going to be the best option for you depending on your circumstances: Do you have a garden? Do you have alternative water sources to flush with? How many people? What can you afford?
* Do some research now on your preferred method - there is a lot of information on the internet, and we link you to some reliable sources below.
* Think about doing a ‘dry run’ and test your method (if it’s something simple like a bucket) so you know what you need.
* Weiss is media manager for World Wide Fund for Nature SA.