Description

 

Rainwater harvesting is simply the collection of rainwater falling upon a roof area which is subsequently filtered and stored in a tank for later use. When required, the water is pumped to the point of use, thus displacing what would otherwise be a demand for mains-water and its intense energy consumption associated with cleaning, production and transportation. Furthermore, the stored rainwater reduces flooding risks by maintaining an equivalent amount of water in the storm water management system.

 

Rainwater harvesting is not a new concept; however, over the last century its use has diminished with the availability of a clean, cheap and reliable water source through the mains supply.

 

More recently, water demand has started to exceed supply, and localised flooding has become an issue. Industry experts are now recognising the important role that rainwater harvesting (also known as rainwater recycling, and greywater recycling) has to play in alleviating both these problems.

 

Rainwater harvesting systems overview

 

Rainwater is captured from the roof(s) and brought to a central point, via normal guttering and drain-pipes, to enter a storage tank (frequently underground), where it is filtered on entry. A highly efficient and reliable submersible pump delivers the water to the location required on demand; alternatively delivery can be to a normal header tank instead.

 

The size of the storage tank is determined by considering the amount of water available for storage (a function of roof size and local average rainfall) and the amount of water likely to be used (a function of the building's occupancy and function).

 

Reasons for rainwater harvesting

• Rainwater harvesting (including rainwater recycling and some versions of greywater recycling) displace a large proportion of the water that would otherwise be provided by the mains supply - thus reducing overall water supply costs and the energy embodied in cleaning and transporting it.
• It can provide an off mains supply for remote areas ensuring security of supply.
• It enhances a property and gains Eco-homes rating points.
• It can form part of an attenuation and rainwater management scheme, by reducing storm-water runoff and controlling the flow rate off site.
• Increasingly planning departments are looking more favourable towards the concept of rainwater harvesting.

 

Please feel free to get in contact with us by email or call 0845 189 9894 to discuss any of your requirements.