Rainwater harvesting is the collection of rainwater before it flows into the general water system which is then reused for domestic, commercial or industrial purposes.
Although there is no real water shortage in the UK, rain does not fall consistently and in recent years there have been droughts and hosepipe bans. Before designing a system you need to decide how much water you need to store by calculating how much you use in a day. Rainwater is best used for supplying household appliances and in the garden. A complex filtration and purification system is needed in order to ensure drinking water is safe. Rainwater is most commonly harvested by collecting rainwater from the roof guttering into barrels or tanks, and from areas of paving or tarmac. In the UK rainwater harvesting can reduce mains water usage by up to 50%. Rainwater harvesting offers many advantages. There is no need to use mains water for laundry/ car washing or flushing the toilet and in addition to it being free, rainwater is free from harmful chemical free which is better for plant health and soil conditions.