Key impact - Water scarcity

Rainfall varies across the country but it's not always available where and when we want it. In the UK, the three regions area gets the least rain, but with the highest population density. As it is, there is only just enough water to go round. A long, hot summer can put pressure on our reservoirs and lead to hosepipe and sprinkler bans - or even standpipes in the streets.

Climate change projections suggest that by 2040, we'll get a third less rainfall in the summer than we do now. Although winters will be wetter, we don't have enough places to store water all year round. Currently, rainfall varies from year to year - 2006 was a drought year, but 2007 saw plenty of rainfall and reservoirs were full. This variation will continue in the future.

In addition to the impacts of climate change, more housing developments are being built in the south east, so increased usage of dishwashers and washing machines in these homes will add to the strain on the water supply. There will be less water to go around, and more of us using it.

It is vital that we are more careful with the water we've got. Adapting your home to use less water isn't difficult. If you have a water meter, a few simple measures will pay for themselves in under a year by saving money on your water bill.

• Being more efficient with hot water means saving on fuel bills - and reducing your carbon emissions at the same time
• Using a water butt avoids using mains water for plants, and efficient toilets can cut the volume you flush away by half
• Low-flow shower heads are designed to use less water without sacrificing water pressure

Although they use less water, all of these devices have been designed to work as well as - or better than - a standard, water-guzzling equivalent.