Climate change is already affecting our weather. The UK is coming out of the coldest winter for over 30 years and rainfall patterns are changing too. The old saying "Rain before 7, fine before 11" no longer seems to apply and the UK climate is likely to continue to change - but not even the experts can predict how. Let's face it, they have been fairly wrong up to now, as flooding, not water shortages due to the UK's predicted 'Mediterranean Climate', seem to be the norm.One thing is certain though, household water consumption is increasing per capita, and if the climate warms other usage will increase, so new ways will have to be found to reduce, reuse and store water for our homes and businesses.
Rainwater harvesting must be considered as a plan towards more sustainable development. The advantages to us and the wider environment of preventing flooding are imeasurable.
The first step towards sustainability should always be to reduce the amount of water we use by installing water efficient appliances, taps, shower heads and toilets. Next we should look at replacing the high quality drinking water we use for low grade uses such as toilet flushing, process water in commercial applications and water for irrigation and animal husbandry. There is no point in using expensive clean drinking water for washing the floor and 50% of all the water used in the home does not need to be of drinking quality. Rainwater Harvesting is not a new idea. The Victorians used it extensively and in the 1980's the Germans made it into an industry. Most of the systems currently available in the UK are either German or use German components, though some Companies now manufacture them in the UK. This reduces their intrisic carbon footprint and the need for the tanks to be assembled on-site, which can lead to problems with leaking tanks.
Rainwater Harvesters not only store the water for reuse, but they also help to avoid the flash run-off which contributes to the flooding of rivers. This will occur as a result of run-off from covered ground and sealed surfaces. Sustainable Urban Drainage Systems (SUDS) are becoming more of an issue and are often a condition of planning permission. The developer is required to slow down the water run-off rate from the site. There are many ways of doing this but it makes sense to reuse the water.The water authorities are now asking for considerable price increases. This is where rainwater harvesting systems will reap big rewards and the pay-back time will vastly reduce. The pay-back period for many commercial sites with large roof areas and a high water demand is already measured in only months.
