A £50 million flood defence scheme has opened in Leeds, in the north of England, which uses moveable weir technology, a first for flood risk reduction in the United Kingdom.
“As could be seen by the devastation at Christmas 2015, providing increased flood protection in Leeds is essential in terms of reassuring our residents and businesses,” said Judith Blake, Leader of Leeds City Council. “The clever use of the mechanical weirs is a brilliant idea, and they have also brought about environmental benefits with the improved river quality bringing salmon and otters.”
The first phase of the Leeds Flood Alleviation Scheme not only uses new flood defence engineering techniques, but also is one of the largest river flood alleviation schemes in the country. Led by Leeds City Council in partnership with the Environment Agency, the scheme will provide more than 3,000 homes, 500 businesses and 300 acres of development land with increased protection against flooding from the River Aire and Hol Beck.
More than 22,000 jobs will be safeguarded over the next 10 years due to the increased level of protection and through the scheme’s development and construction, 150 jobs and apprenticeships have been created. It comprises three main elements: mechanical weirs, the merging of the river and canal and floodwalls and embankments stretching 4.5 kilometres through the city centre.
“We’re always looking for new ways that we can use technology to reduce flood risk so it’s exciting that this scheme is also a first for flood risk management in the UK thanks to the use of the moveable weirs which can be lowered when river levels are high,” said Emma Howard Boyd, Chair of the Environment Agency. “On a day-to-day basis, people won’t even know they are being protected, and they can enjoy the river which is a key aspect of the city’s South Bank regeneration plans.”
It is the first time that moveable weirs have been used in the UK for flood alleviation purposes. The new weir gates are supported by giant inflatable neoprene bladders that can be lowered when high river flows are expected. It takes around two hours for the gates to lower, and thanks to the installation of these weir gates, it has been possible to keep flood defence wall heights to a minimum so as not to spoil views of the city centre waterfront.