§ Mr. Llew SmithTo ask the Secretary of State for the Environment what assessment he has made of the effects of the construction of housing on river flood plains exacerbation of recent floods in the south and east of England.
§ Mr. JackI have been asked to reply.
In December 1992, the Ministry together with the Department of the Environment and the Welsh Office, issued updated guidance to local planning authorities on the need to take account of flood risk due to increased run-off from new developments and the need for measures to be taken to alleviate this as a condition of granting planning permission. The National Rivers Authority provides advice to local planning authorities on application for developments in flood risk areas.
The Ministry has an ongoing programme of research into the flood response of rivers to rainfall and the development of design procedures which can take into account changes within river catchments such as urbanisation. Changes in flood run-off can be assessed in a number of ways, including by reference to 1975 flood studies report by the Institute of Hydrology, which has been substantially updated through Ministry-funded research. It is for the National Rivers Authority and the other responsible flood defence bodies to assess the causes of flooding on individual rivers using these techniques.