The apparent madness of using fresh drinking water to flush the toilet or water the garden partly explains the appeal of reusing bath and shower water or rain from the roof for these purposes.
However, for UK homes, it is more cost effective to save water than to reuse rainwater or greywater. Also, efficiency measures save energy and CO2 emissions, whereas greywater and rainwater systems often increase the total amount of energy and emissions.
Where gardens need a lot of watering, simple, low cost greywater diversion systems can save considerable quantities of water at a time of peak demand. Similarly, the humble water butt is able to capture rain from summer showers, allowing gardeners to apply the water where it is needed most.
See below to find out more about how you can reuse greywater and rainwater for garden watering and toilet flushing
Collect and reuse rainwater
You can help the environment by reducing the demand for mains water so less has to be taken from the environment.
Collecting rainwater is really easy, it doesn't cost much to do and means you can keep watering during the summer or whenever there are water restrictions. Most plants prefer rainwater to tap water.
Using rainwater you use less tap water, which will save you money if you're on a meter.
Top tips for collecting rainwater:
- Buy a water butt from your water company, gardening or DIY centre or online
- Fit a water butt on every downpipe on your house, shed, garage or greenhouse
- Increase your storage by connecting several water butts together or just get one big butt if space allows
- Remember: be safe with your water butts - always follow the manufacturers' fitting instructions and make sure they have tight-fitting lids and cannot topple over
Longer term solution - rainwater harvesting
If you have the space and money, you could think about installing a rainwater harvesting system at your house. You sink a large tank in your garden, which you could then pave or deck over. This collects water to use in your garden and in the house to flush toilets.
Install a greywater system
Wastewater from all sources in a property other than toilets is known as greywater.
Most greywater recycling systems collect and treat wastewater from showers, baths and wash basins, excluding the more contaminated water from washing machines, kitchen sinks and dishwashers.
Greywater recycling systems collect this water, treat it and re-use it for purposes that do not require drinking water quality. This recycled water can be used to flush toilets, water gardens and sometimes feed washing machines.
Greywater recycling systems can be installed in new or existing buildings and have the potential to meet a significant proportion of domestic demand for water.
For more information see our document:
Further information
Read The New Create an Oasis with Greywater: choosing, building, and using greywater systems, includes branched drains by Art Ludwig
This information gives guidance only. It should not be treated as a complete and authoritative statement of measures to be adopted and their results. You are advised to make your own investigations before deciding on any course of action. The Environment Agency does not endorse the use, purchase and/or the performance of the goods or services provided by companies mentioned herein.
