Does South Africa have a water crisis or simply a water problem?

[noxibox]

If it is a distribution and losses problem then there is no point discussing desalination or more dams. The distribution failures would probably just get worse and consume the additional supply.

If you have rain all year round then harvesting for personal use is a viable option and you won’t need substantial tanks. If you mostly get rain in the cold months, then it won’t help you if water supply is interrupted during the hot months. Unless you have space for big tanks.

Reusing grey water makes a big difference. You can recycle water quite a few times at home without any issues. For instance shower water that went through a settling tank is fine for washing machines, toilets, garden etc

Based on experience the toilet is pretty much the only thing for which I would use grey water.

 

[B-1]

If it is a distribution and losses problem then there is no point discussing desalination or more dams. The distribution failures would probably just get worse and consume the additional supply.

If you have rain all year round then harvesting for personal use is a viable option and you won’t need substantial tanks. If you mostly get rain in the cold months, then it won’t help you if water supply is interrupted during the hot months. Unless you have space for big tanks.


Based on experience the toilet is pretty much the only thing for which I would use grey water.

I agree that it will more likely be an infrastructure issue. If there is a total collapse of infrastructure all these measures won't help much as there are other issues like food, sewage, safety etc that are harder to be self sufficient on. Its more realistic to have something that can sustain you for a week or two while repairs are done to pipes or pumps similar to our power issues.

But reusing grey water is still good as its such a waste to just dump that water down the drain when its perfectly fine to use in the garden.

 

[Geoff.D]

RO system under the sink/counter-top RO system?

Yes, in PTA we had the filter installed in a cupboard below a prep sink. In CT the filter is outside at the moment connected to a new pipe I have installed, which be moved into the kitchen when we get round to the renovations. I have used a normal tap for this system.

 

[Geoff.D]

If it is a distribution and losses problem then there is no point discussing desalination or more dams. The distribution failures would probably just get worse and consume the additional supply.

We have all the problems, no new dams, no infrastructure maintenance and no political will to do anything.

If you have rain all year round then harvesting for personal use is a viable option and you won’t need substantial tanks. If you mostly get rain in the cold months, then it won’t help you if water supply is interrupted during the hot months. Unless you have space for big tanks.

Ja. And most new developments have no place to undertake mass water storage. Those small Jojo tanks are just to make people feel good. To be effective, one has to be able to store sufficient water to tide you over for the full duration of the dry period. So, say it is 6 months and the monthly consumption is 20 kl, then the storage required would be 120 kl! That is 120 000 litres! The average home pool is 40 000 l which means you need 3 of them! Way beyond logic to try and do.

Even if the monthly consumption is 6 kl, that still means you need to store 36 000 litres - one home pool.

Based on experience the toilet is pretty much the only thing for which I would use grey water.

Agreed. You can't do anything with grey water in the home except flush toilets and then only after filtering the grey water. The only relatively easy use of grey water is to use it in the garden, and then again, it would need at least some filtering first.

 

[Paul_S]

Those small Jojo tanks are just to make people feel good. To be effective, one has to be able to store sufficient water to tide you over for the full duration of the dry period. So, say it is 6 months and the monthly consumption is 20 kl, then the storage required would be 120 kl! That is 120 000 litres! The average home pool is 40 000 l which means you need 3 of them! Way beyond logic to try and do.

A lot of people don't do those sums and then they are really surprised at how little they can water their garden from four or five 1500L rain water catchment tanks. If there is adequate rainfall in the area which is replenishing the ground water then it makes much more sense to drill a borehole for water.

If rain water is all one has access to and boreholes are banned then I guess it makes sense to go that expensive route.

 

[bwana]

Ja. And most new developments have no place to undertake mass water storage. Those small Jojo tanks are just to make people feel good. To be effective, one has to be able to store sufficient water to tide you over for the full duration of the dry period. So, say it is 6 months and the monthly consumption is 20 kl, then the storage required would be 120 kl! That is 120 000 litres! The average home pool is 40 000 l which means you need 3 of them! Way beyond logic to try and do.

Six months seems a little excessive. And who is filling a 40,000l pool on a regular basis?

With my rainfall patterns I can manage quite well on the 12Kl I have, though if I were to go completely off grid I might add another 5Kl for maintenance and I'd connect the other 2/3rds of my roof to the system. As I mentioned though it's not really cost effective. Municipal water is cheap.

What those smaller JoJo tanks can offer though is a stop gap for "water shedding" or other outages.

If there is adequate rainfall in the area which is replenishing the ground water then it makes much more sense to drill a borehole for water.

How much does a borehole cost where you live? Ballpark estimate.

 

[Geoff.D]

12Kl I have,

12 000 litres is impressive. At 6 000 l per month, that is two months' backup. At our place in CT, we would only be able to install 2 x 750 = 1500, which equates to 1-week water based on the 6 kl per month target we are trying to get to.

 

[Paul_S]

How much does a borehole cost where you live? Ballpark estimate.

A year ago I paid just over R60 000 to have a 96 meter deep hole drilled (R500/meter). That included some steel casing at the top in the overburden and 96 meters of PVC casing to the bottom. The pump costs about another R10 000 to R20 000 depending on quality/brand.
The going rate can be up to R1000/m but I shopped around.

It costs me about R2 in electricity to pump one kL of water but that will become zero once my solar is installed. I now have cheap, clean and potable water all year long which I'll hook up to the house next year (I need to install a calcite filter to correct the pH of 6.4 to above 7 else it will corrode the copper plumbing).

 

[bwana]

A year ago I paid just over R60 000 to have a 96 meter deep hole drilled (R500/meter). That included some steel casing at the top in the overburden and 96 meters of PVC casing to the bottom. The pump costs about another R10 000 to R20 000 depending on quality/brand.
The going rate can be up to R1000/m but I shopped around.

It costs me about R2 in electricity to pump one kL of water but that will become zero once my solar is installed. I now have cheap, clean and potable water all year long which I'll hook up to the house next year (I need to install a calcite filter to correct the pH of 6.4 to above 7 else it will corrode the copper plumbing).

I like the idea of a borehole but around here most of what people are pumping up is somewhat brackish. I think they're tapping into a series of underground springs rather than the water table because they're probably only going 15m down. Unfortunately my own borehole is going to have to wait a while.

My rainwater storage cost me around R1 a litre and the pump was another grand or two and it's entirely scalable. If our day zero materialises I can quickly install more tanks.

12 000 litres is impressive. At 6 000 l per month, that is two months' backup. At our place in CT, we would only be able to install 2 x 750 = 1500, which equates to 1-week water based on the 6 kl per month target we are trying to get to.

We have a lot of roof space and a corresponding amount of room for tanks. However due to the way our roof is segmented we have we're only currently utilising about 100 sq m for collection, There are at least another 8 downpipes I could harvest from - connect a 1000l slimline (or even a cheap 1000l flowbin) to each of those and I'd never have to worry about municipal water again. Even below monthly average rainfalls would be sufficient.