Rainwater harvesting simply collects the rain which fall onto roofs, then stores it in a tank until required for use. When required, the water is then pumped to the point of use or to a secondary tank (header tank or break tank), thus displacing what would otherwise be a demand for mains-water. In the process, a volume of water is kept out of the storm-water management system, thereby helping to reduce flooding risks.
The interest in Rainwater Harvesting has been growing in recent years and was given a significant boost during 2006 with the introduction of severe water use restrictions across the south. Without the ability to undertake supplementary watering with a hosepipe most people realise that a simple water butt is no longer sufficient for their needs. Combined with rising water costs and the desire to be more environmentally friendly many are looking for more comprehensive options.
With this in mind we have brought together a range of products to cater for most applications, from 650 litre surface mounted wall tanks with simple downpipe diverter, to 36,000 litre underground GRP tanks.
It is worth noting that many householders assume rainwater and grey water are the same thing (grey water being from showers, baths, sinks and some washing machines). Whilst there are filtering systems that are designed to cope with this type of water it is more involved and more costly.
In some cases the client may insist that they wish to collect grey water therefore you should make them aware that organic detergents/shampoos should be used, the filter will require very regular inspection and cleaning, that this type of water may not store well over longer periods and it should not be used on vegetable or fruit gardens.
Collecting rainwater is straight forward, using existing roof drainage systems the rainwater is filtered and diverted to exclude the larger leaf debris and other particles, with secondary filtration occurring in the storage tank via settlement with heavier particles falling to the bottom and lighter particles floating to the top. This process is all done by gravity and the cleanest water is then pumped out via either a floating suction filter or a pump placed on a platform above the accumulated particles on the bottom.
This water is then distributed to required locations around the property i.e. garden taps or irrigation system. During prolonged dry periods, and the tank is empty, there are several easy ways of providing an automatic mains water backup supply to the storage tank.