Re-using and harvesting water

Find out about re-using rainwater and greywater recycling systems.

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. Doing this will save energy and reduce CO2 emissions, whereas greywater and rainwater systems often increase the total amount of energy and emissions.

When gardens need a lot of watering, simple, low cost greywater diversion systems can save considerable quantities of water at a time of peak demand. Water butts can collect rain from summer showers, allowing gardeners to apply the water where it is needed most.

Collect and reuse rainwater

You can help the environment by reducing the demand for mains water.

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. You will also save money if you're on a meter.

Top tips for collecting rainwater:

  • Buy a water butt from your water company, gardening or DIY centre.
  • 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.

Longer term solution - rainwater harvesting

If you have the space and money, you could install 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:

More information

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.