Greywater describes household water which has already been used in showers and baths, or collected from rain sources. It can then be used for a variety of additional non-drinking purposes, such as watering the garden or flushing the toilet, and it acts as a powerful measure to reduce waste. After all, why do we need to use fresh drinking water simply to flush our toilets, or to water garden plants!
Households that are looking to save carbon emissions and costs by reducing their water intake can further increase the benefits by installing low-cost greywater systems. The most common solution is via outdoor water butts, which collect rainwater and make it instantly available to gardeners. Water butts are cheap, easy to install, and greatly help the environment. They also benefit plants, which prefer natural rainwater to chemically-filtered tap water. You can buy a water butt from your local DIY centre or garden centre, or from your water company.
Those with space and resources to do so may wish to install a larger harvesting system for rainwater in their home by sinking a collection tank into the garden – under decking for example – to collect water for garden use, and toilet flushing.
There are various greywater systems available commercially too. They can generally be installed in both new and older buildings and they offer the potential of meeting a large proportion of the average household’s demands for water.
The Environment Agency [http://www.environment-agency.gov.uk/] is a good starting point for further information, along with the UK Rainwater Harvesting Association: [http://www.ukrha.org/]