The recent publication of British Standard 8515 for rainwater harvesting systems, available via http://www.bsigroup.com/, establishes for the first time a yardstick against which systems being supplied in the UK can be measured.
Harvesting rainwater to supply household needs is one of the oldest and most durable forms of supplying water worldwide, although until recently practiced in the UK mainly in the context of garden irrigation, following the introduction by the Victorians of mains-supplied water.
Due to modern lifestyles and population growth, however, UK mains water supplies are now coming under varying degrees of stress – particularly in England south of the Humber where the stress is generally severe (see Environment Agency map).
This is reflected in the mains water consumption requirements set out in the Code for Sustainable homes, and commercial equivalents such as BREEAM assessments. Up to a point, these requirements can be met by economising on water use, but if lifestyle (baths and showers etc) is not to be compromised then substituting recycled water for mains water becomes necessary.
The easiest and most cost-effective way of doing this is to use harvested rainwater instead of mains water for non-potable uses such as toilet-flushing, clothes washing machines, car washing and irrigation. This reduces mains water consumption by around 50% in the home and by more than 80% in any building that combines a large roof with a high demand for non-potable water.
BS 8515 now sets the standard for how systems as a whole (see schematic diagram) and
components within the system should function. Very simply, the aim is to route the rainwater falling on the roof to a storage tank, filtering it beforehand to remove any solid impurities. When needed, the water is then pumped (directly or via a header tank) to its point of use via pipework dedicated to non-potable water.
From the users perspective, using rainwater in this way is indistinguishable from using the normal mains supply, with the associated controls automatically controlling all functions and ensuring, using a mains water backup when needed during prolonged dry spell, continuity of supply.
Harvesting rainwater to supply household needs is one of the oldest and most durable forms of supplying water worldwide, although until recently practiced in the UK mainly in the context of garden irrigation, following the introduction by the Victorians of mains-supplied water.
Due to modern lifestyles and population growth, however, UK mains water supplies are now coming under varying degrees of stress – particularly in England south of the Humber where the stress is generally severe (see Environment Agency map).
This is reflected in the mains water consumption requirements set out in the Code for Sustainable homes, and commercial equivalents such as BREEAM assessments. Up to a point, these requirements can be met by economising on water use, but if lifestyle (baths and showers etc) is not to be compromised then substituting recycled water for mains water becomes necessary.
The easiest and most cost-effective way of doing this is to use harvested rainwater instead of mains water for non-potable uses such as toilet-flushing, clothes washing machines, car washing and irrigation. This reduces mains water consumption by around 50% in the home and by more than 80% in any building that combines a large roof with a high demand for non-potable water.
BS 8515 now sets the standard for how systems as a whole (see schematic diagram) and
components within the system should function. Very simply, the aim is to route the rainwater falling on the roof to a storage tank, filtering it beforehand to remove any solid impurities. When needed, the water is then pumped (directly or via a header tank) to its point of use via pipework dedicated to non-potable water.From the users perspective, using rainwater in this way is indistinguishable from using the normal mains supply, with the associated controls automatically controlling all functions and ensuring, using a mains water backup when needed during prolonged dry spell, continuity of supply.
No comments:
Post a Comment