Rainfall run-off management for urban developments

This project developed a simple tool for people, who are not experts, to find out what drainage systems a new development is likely to need.


Rainfall runoff management for developments - summary (96KB) PDF

Rainfall runoff management for developments - Welsh summary (87KB) PDF

Rainfall runoff management for developments - technical report (7.2MB) PDF

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This guide gives advice on designing drainage for stormwater for new building developments. The advice was based on current Defra and Environment Agency views on managing stormwater and controlling what’s discharged to drains and sewers from developments.

The guide gives an easy method for setting limits on how much stormwater can be discharged from a site. It explains how to work out how much storage is needed to control stormwater and meet the limits. It uses a simple manual calculation based on look-up tables which means there’s no need to refer to other documents or use specialist software. It should only be used at the planning stage to get an indication of the volume of storage that will be required. It should also be followed up at later stages with detailed designs.

The guide includes explanations and examples based on five UK cities with different types of soil and water systems. It means people who are not experts in drainage can get a quick assessment of what drainage might need to be built into a planned development.

The project started in 2003 and was completed in 2009.

Published 18 February 2021