Rain Water Harvesting
Rain water harvesting involves the collection of rain water from the roofs of buildings, storing the water in a tank and then pumping the water back out for later use. Depending on the amount of rainfall in your area you could see upto a 50% reduction in main's water usage.
Benefits can be even greater for industry who often have much larger roof areas to collect water on and much higher water usage compared to domestic users.
Rain is collected in your existing guttering which is then directed through a filter and into a storage tank. This storage tank can be located either above or below ground. This is connected to a rain water manager (known as MAX) that can be sited in your house. The manager controls flow to the various sources of water usage around the house. If the manager detects that the water tank is empty it will automatically switch to mains supply until the rain water tank can takeover again.
To size a system a calculation based upon roof size, annual rainfall and water usage is made. This is to make sure the correct size of tank is used to avoid running out of water too often and to avoid wasted tank space. The amount of rainfall for your area is acquired from the MET office and your roof area calculated. These two figures along with a run-off coefficient are used to calculate how much rainfall will be captured by your house and this can be used to size your tank.
