This page relates to my water supply at Wantadilla in the
Adelaide Hills in South Australia, where I lived from 1997 to 2007. I currently don't have
a corresponding page for my present house in Dereel.
Some people characterize South Australia as being the driest state in the driest continent
on Earth. We have no mains water supply.
Nevertheless, we don't have much of a problem with water. The rainfall here is many times
the state average, and on our 20 ha (50 acres) of land we get an annual rainfall of about
150,000 cubic metres (about 33 million gallons). We can't collect all of that, of course,
but we have a rainwater tank which holds about 75 cubic meters. Water from a large
proportion of the roof drains into the tank, keeping it full in the winter. In a typical
summer it drops to about half full. In the following photo you can see two green pipes
leading down from the gutter behind the tank, and a 4" white up pipe from the other
part of the house.
It's made by Davey, with whom we
are not satisfied. It's quite a concern to have
your only supply of potable water fail on you, usually on a holiday.
The tank needs cleaning from time to time, about every five years. So far the only time was
on 6 August 2003, and they found an incredible mess in there.
It's a rather stupid place for a dam: it's in the corner of the property, where it hardly
collects any rain water. Closer to the house we have a creek which runs through the property
and carries a lot of water in the winter, but it would cost a significant amount of money to
build a new dam there, and so far we haven't seen a reason to do so.
By the dam we have a “bore”, a pump sunk into the water table 60 metres below.
In this photo you can also see the house in the distance.
The pump delivers a large volume (rated as 9000 gallons per hour, or somewhat over 10 litres
per second) of relatively saline water (about 2200 ppm) into the dam, where it evaporates while
waiting to be used, thus further increasing the salinity. We're thinking of putting in a header
tank and an automatic switch to improve things there.
but in fact they're not really the controls at all. One day we had problems with the pump
and opened the box on the left and found something that looked relatively modern. I even found
a circuit diagram for the thing, which I'm putting on line so
I don't lose it.
We had trouble with dirt in the system, so we installed a filter. The results were
astonishing: just about every day we collect this much junk on the element:
Finally, we have a second water tank partially hidden behind some trees in the garden. It's
full of dam (or bore) water, and it's intended to run the fire pump in case of bushfire.
