East Cambridgeshire District Council Water Cycle Study Detailed ...

1.6 Water Use – Key Assumption
Stage 2 Water Cycle Study: Final Report
Sept 2011
18
Cambridgeshire Horizons
East Cambridgeshire – Detailed WCS
For all wastewater and water supply assessments, an assumption was made on the likely use
per new household going forward in the plan period. It was agreed with AWS that a starting
assumption of 150l/h/d would be used to calculate wastewater generation and water use per
person, and that this figure would also allow for estimated use in schools, hospitals and
commercial property.
It is acknowledged that this figure exceeds the current Building Regulations requirement of
125l/h/d for all new homes. However, in their asset planning AWS will continue to assume this
higher water use for new homes as their analysis has shown that even when homes are built to
a standard of 125 l/h/d, the average household use increases over time due to various factors.
AWS are required under their remit to the industry regulator Ofwat, to plan for the expected
actual use and hence it is important that conclusions made on infrastructure capacity within this
study are consistent with AWS’ planning strategies.
This study has however considered the effect that achieving lower average per person
consumption would have on infrastructure capacity and the water environment to assist in
developing policy that supports and helps lead to a lower per capita consumption.