Outer London boroughs could use green spaces such as parks and playing fields to help reduce flooding risk in the capital, the London Assembly heard yesterday.
The Assembly’s Environment Committee is currently investigating river and surface water flooding in London; it is estimated that in the capital around 100,000 properties are at risk from river flooding and up to 680,000 at risk from surface water flooding.[1] [2]
Robert Oates, of the Thames Rivers Restoration Trust, told the Committee that small tributaries buried underground or diverted through concrete channels could be broken out and redesigned so they use existing green spaces as flood plains, keeping water away from homes and buildings. He said almost every single outer London borough has the potential to use open areas such as parks and school playing fields in this way and it could be more cost-effective than trying to restore ageing concrete systems.
Dave Bedlington, of the Environment Agency, also told the Committee that if London were hit by the kind of severe storms that affected other parts of the UK in 2007, flooding could occur within minutes, with fast flowing water in some streets, and he would expect lives to be lost. Nick Starling, of the Association of British Insurers, added that if similar storms hit London he would expect the cost to be considerably greater than the £3 billion cost of the 2007 floods.
Darren Johnson, Green Party Assembly Member, and Chair of the London Assembly Environment Committee, said: "Flooding is a serious risk for thousands of Londoners and the events of 2007 should act as a warning to the capital.
"Using green spaces to restore flood plains is an innovative solution to this problem and may in the long run be more cost effective than building higher and higher concrete walls. We have seen for ourselves some excellent projects that exist in the capital, and the Committee is keen to explore whether more can be done to help protect Londoners from the risk of flooding."
As part of the investigation, members of the Environment Committee recently visited two river restoration projects, the River Quaggy at Sutcliffe Park in Greenwich[3] and Cornmill Gardens in Lewisham.[4]
Notes for Editors:
1. The risk of flooding for the 100,000 identified properties, with existing protective measures, is typically one to five percent in a year. See the Mayor’s draft Water Strategy, page 62
2. Detailed maps do not yet exist to calculate surface water flooding risk in detail but it is thought there are up to 680,000 properties in London at risk with a likelihood of at least 0.5 percent in a year. See the Mayor’s draft Climate Change Adaptation Strategy, page 42, based on Environment Agency data.
3. London is at risk of flooding from five sources: tidal, river, surface water, sewer and groundwater.
4. The Committee’s investigation is focused on surface water and river flooding. Further details of the investigation are available here.