To ask the Secretary of State for Environment, Food and Rural Affairs what assessment his Department has made of the effect of combined sewers on flooding; and what estimate his Department has made of the cost of (a) removing and (b) phasing out combined sewers. (175988)

The Government's Foresight (2004) ‘Future Flooding’ report estimated that currently 80,000 properties are at very high risk from surface water flooding (10 per cent. annual chance), causing on average £270 million of damage each year.

Water and sewerage companies have a statutory duty under section 94 of the Water industry Act 1991 to ensure that their area is effectually drained. The water industry sponsors research on a range of projects related to sewerage systems and the organisation, UK Water Industry Research is, I understand, undertaking one specifically “exploring the cost benefit of separating surface water”.