Rainwater Harvesting

Rainwater can be collected for non-potable purposes such as for flushing W.C’s, general cleaning or for irrigation systems. Rainwater is collected in the traditional manner from the building outlets and is piped to a storage tank or tanks. The tank is generally sited underground as this helps to maintain a low storage temperature and helps prevent possible algae growth. Separate non-potable distribution pipework is installed to service the outlets within the building with suitable booster pumps and filtration units.

A back-up cold water mains supply is installed to the storage tank in order to top-up supply. Rainfall quantities very rarely coincide with the building demand, therefore suitable storage is necessary to ensure efficient use of this resource. Also, taking into account the amount of contaminants in the water will be a factor in assessing the amount of reclaimed water stored relative to the number of days the water remains in storage.