As a follow up it is worth noting that proposed changes to the building regulations are currently out for consultation.
The proposals include increasing the scope of the regulations to cover water efficiency and alternative supplies for certain uses.
The consultation document can be found at www.communities.gov.uk/publications.
Efficiencies are only proposed for new dwellings since BREEAM is the driving force for other building types.
As a result, we see examples of rainwater harvesting providing grey water for secondary uses thereby reducing the demand for treated water and the quantity of waste water discharge.
DAVID CLEMENTS (M), district surveyor, Department of Environmental Services, City of London, PO Box 270, Guildhall, London EC2P 2EJ