Water Supply in Dry Areas

Living with a limited water supply

Increasingly people are finding themselves living in areas with very limited water supply. By checking our water usage we will probably find we are using a lot of water and this can be reduced without a great deal of difficulty though we may have to be willing to change the way we live. Here we look at steps to take to reduce how much water you use and even become self sufficient with water.

A Dry Area As An Example

People who live in dry areas will often have problesm with their water supply. An area in Southern Bali is a high area of limestone which drains quickly, the trees have been removed and as a result it is a very dry area. Some 10 years ago the residents banded together and collected money to pay for government water supply pipes. Pipes were installed and people were able to get government water. This system worked well for many years but some time ago, without warning, the supply was turned off.

Many residents have now had to revert to their earlier arrangements. They buy in tankerloads of water. Some are buying as much as a full tanker a day at a cost of $20 for a 5,000 litre truck. That's a lot of water to say nothing of the cost and we have to wonder what they are doing to use so much.

There are unfortunately further problems. Different truck operators have their established turf. Local people insist that only certain water truck operators can supply in their areas. With a monopoly the water truck drivers have the residents at their mercy.

The trucks go to Jimbaran to pick up their loads of water from a bore. The water is often polluted with sand and salt.

So what can people do? Let us consider their options.

Install a Bore

You might consider installing a bore, though this may be challenging. In tis area the land is coral stone with a thin layer of topsoil. Coralstone is a weak chalk-like stone and the thing about this kind of rock is that it is very porous, it doesn't hold water at all so the water table here is very low and probably as low as sea level.

Because of this a bore will have to be as much as 150 metres deep, that's deep. To pump water up from this depth you will need a powerful submersible pump. A pump of this type will be very expensive and will use a lot of power.

We found someone who had a bore drilled but unfortunately the driller made a mistake and the bore hole has a bend in it, the pump jams in the bend and so cannot reach the water below.

Harvest Rainwater

You might consider installing a large water tank and some guttering to fill the tank with rainwater from the roof. If you are building a new house you might consider building a large capacity tank into the foundations to store rainwater. This may sound like a drop in the ocean compared with what your demand might be but don't be too sceptical. Concrete water tanks are being built in remote areas around the world where they have exceptionally long dry seasons and it has been found that one such tank in Bali quickly fills in the wet season then provides water for over 30 families for the rest of the year.

Reduce the water you use

It goes without saying that you will need to minimise how much water you use.

Find and repair any water leaks

Start off by checking that you don't have any leaks. We can all do this no matter where we live on the island. Make sure everything is turned off and go and listen to the water pump. Many of us have 2 pumps, one for the bore or well which pumps water to a water tank and a second one to pump water from the tank to taps, toilets and showers. If you have 2 pumps identify the pressure pump, the one after the water tank, this is the one you check. If you only have one pump then check that one.

if everything is turned off the water pump should not be running. If it keeps switching on and off you have a small leak. If it continuously runs you have a large leak. If you do have a leak start off by checking that toilets are not running or taps are not dripping. If you still have a leak call someone, it can be very frustrating trying to find a leak in your water supply system.

Are you using a lot of water to top up that swimming pool everyday? You will naturally lose water from evaporation but this shouldn't be too much. If you are topping up a lot perhaps you have a leak somewhere in the swimming pool or, more likely, the pipework for the pool.

Check your water usage

Ok, no leaks, what next? Perhaps you need to work out a plan to manage you water usage, a 5,000 litre truck every day is a lot of water. It is amazing how little you need if you are careful. A starting point might be to check out your usage on the water usage calculator on our website at http://www.mrfixitbali.com/waterusagecalculator.html

Rcycle grey water

Some people are recycling their grey water (from showers and washing machines) to irrigate the garden. I recently saw some very efficient drip feed watering systems that use a fraction of the water to keep plants healthy simply by measuring the supply and placing exactly where it is needed.

Hydroponic gardens

Another possibility is hydroponic planting. Hydroponic growing of plants uses a fraction of the water needed for plants growing in an open garden. You can have lush green vegetation while using minimal water.

Plant Trees

Planting trees might be a good idea, nice green trees. Shade will reduce the amount of water the garden needs.

Backwashing wastes water

Beware of backwashing water filters and purification equipment. I have seen a number of reverse osmosis machines that use a very substantial amount of water to backwash the filter membrane. Swimming pool, sand filters and water softeners also use backwashing which of course throws water away. Perhaps your backwash could go into a tank to be used for the garden later.

Change Your Lifestyle

By changing lifestyle we can save a lot of water, this can make harvesting rainwater a viable proposition.

Get rid of the swimming pool, they waste huge amounts of water.
Install low usage showerheads and toilet cisterns
Replace gardens that need watering with dry climate gardens.
Wash the car in town.
Use a brush rather than a hose to clean the garage and drive.
Bath with a friend.