WWF-funded wetland saves Doncaster homes from flooding

England and Wales were hit by record flooding in June that caused damage estimated at more than £1 billion by the Association of British Insurers. On 25 June, up to a month’s rain to fall in 24 hours in many areas of the north and west. Severe weather conditions caused 15 rivers to burst their banks, flooding 27,000 homes and affecting 5,000 businesses. Five people lost their lives.

Yorkshire suffered its wettest June on record. In the town of Catcliffe, the River Rother rose more than six metres in a matter hours, partly owing to water being pumped from the Ulley Dam, which was in danger of collapse.

Rob Oates, manager of WWF’s Natural Rivers programme, visited South Yorkshire shortly after the floods had subsided, to compare the town’s hard defences with the more natural system in South Doncaster, where the WWF-backed Potteric Carr wetland nature reserve is designed to store floodwater in the case of such extreme events.

The new wetland extension at Potteric was completed last year at a cost of £1.4 million including £440,000 from WWF, delivered through our Investing in Nature partnership with HSBC. The new wetland covers 75 hectares and was designed to provide habitat for rare wildlife such as the bittern. It also helps to filter and clean waste water from 10,000 homes and acts as a recreation area for some 27,000 visitors per year.

It has acted as a natural flood defence system far sooner than expected. As drains carried storm water from South Doncaster, and the River Torne backed up as far as Potteric Carr, flood waters spilled safely over the banks onto the reserve and the new extension.

“The banks of the new wetland have stood up to the worst floods ever seen in this area,” said Rob Oates. “And the wildlife has taken refuge on the islands designed for it. We had expected this wetland to help cope with increased flooding from climate change, but we had not expected that to come just six months after construction!”

The floods have increased calls from politicians and others for more flood defences to be built. The Environment Agency has asked government to increase its flood management budget from £500m to £650m, rather than the £15m of cuts imposed last year. Experience from Potteric Carr shows that multi-functional flood water storage areas would be a cost-effective use of the funds for many towns around the UK.

A similar WWF project on the River Devon in Scotland has shown that natural flood management techniques, such as restoring wetlands in the upper parts of rivers, can cost just one tenth of the amount required to build traditional hard defences further downstream.

Around five million people in England and Wales live at risk of river or coastal flooding. Some two million homes have been built on flood plains or vulnerable parts of the coast and there are plans to build 200,000 more on land behind flood defences in the Thames estuary.

Gordon Brown’s pledge to provide greater numbers of affordable homes will only add to the pressure. His new ministers at Defra need to ensure that the Environment Agency gives higher priority to producing Catchment Flood Management Plans for rivers and that it follows its own policies in creating multi-functional wetlands similar to that in Potteric.

WWF will be expanding and promoting its work on freshwater adaptation to climate change over the next five years as part of the HSBC Climate Partnership. For more details visit www.hsbccommittochange.com

Posted 10th July 2007