Climate Change & Water Demand
57,000 UK homes flooded in 2007
With average UK annual temperatures predicted to rise by up to 3.5°C over the next 70 years, climate change is already driving the need for innovative solutions to the management of rainfall and surface water. Changing rainfall patterns are likely to lead to wetter winters and drier summers, sea levels are expected to rise and extreme weather events look set to become far more commonplace. The summer of 2007 gave a clear indication of the consequences that these sorts of changes can bring when 57,000 UK homes were affected by surface water flooding which caused £3 billion of damage. With so many homes and commercial developments, plus much of our major road network in the UK currently facing a real risk of surface water flooding, now is the time to take action.
Water consumption up 50% in 25 years
The average person in England and Wales now uses 150 litres of water every day - almost 50% more than 25 years ago. Washing and toilet flushing account for much of this figure, with drinking, cooking, car washing and garden watering also playing large parts. Yet while continental countries such as Italy and Spain enjoy water supply capacities of on average 2,785 m³ per person, per year, England and Wales has a surprisingly low capacity of just 1,334 m³ per person. The high population densities in areas such as South East England mean that there is even less water available to each person in these regions.
Rainwater re-use reduces demand
Rainwater re-use solutions offer a way to address this increasingly important issue by collecting and recycling rainwater, rather than simply allowing it to drain away. This not only reduces the demand for mains water for toilet flushing, laundry, vehicle washing and irrigation purposes, but also eases the potential for flooding which can be created when rainwater deposited by extreme storms is simply left to run to ground.
On average a non-domestic building uses approximately 2,600 litres a day, with up to 80% of the water delivered for non-potable applications such as toilet flushing. Much of this could be provided by harvested rainwater.
On average a domestic dwelling uses 150 litres per person per day, with approximately 50% of the water delivered for non-potable applications such as toilet flushing, washing machines and garden irrigation. Much of this could be provided by harvested rainwater.