Rainfall Intensity for Sewer Design - Technical Guide

Price: £50  

UK water and sewerage companies do not have a way of assessing the growing risk of customer flooding and pollution from CSOs. Previous research for UKWIR used UKCIP02 and UKCP09 projections and data. However, short-period rainfall statistics used to assess existing and new sewer systems are largely the result of convective rainfall.  Convective rainfall processes are not well simulated by Regional Climate Models (used in UKCP09 and predecessor projections).
Addressing this issue, this project has produced estimates of rainfall intensity change over different parts of the UK using a combination of climate analogue data and a high-resolution (1.5km) climate model developed by the UK Met Office both approaches capturing or resolving convective rainfall events. The resultant rainfall intensity change estimates are, in general, higher than existing UK guidance suggests.

Sewer flooding frequency and volume, and frequency of pollution events are also investigated for five locations; indicating that these are also likely to increase in the future. It is recommended that further work is undertaken to add confidence to the results produced and to inform future UK guidance.



UKWIR Reference :- 15/CL/10/16-1Published Date :- 06/07/2015
Retail Price (£) :- 50ISBN :- 184057 771 1


Supporting Material and Reports

Rainfall Intensity for Sewer Design - Guidance to Water Companies