Concrete is out and natural flood remedies are planned on Bransholme, our woodland gully correspondent Angus Young reports.
In June 2007 hundreds of homes in Bransholme and Kingswood were flooded when the Bransholme pumping station failed during prolonged heavy rain. Nine years later a massively-upgraded pumping station was opened after a £16m investment by Yorkshire Water. As part of the facelift, six 92 ft-long screw pumps were installed to help move rainwater from the sewage system serving the wider area into an adjacent storage lagoon before being slowly released into the River Hull. Even with the new pumps, efforts continue to divert surface water away from the sewerage system wherever possible to reduce the risk of flooding because of its limited capacity to cope with extreme rainfall.
Projects large and small have been completed ever since the 2007 floods and one of the smallest is about to get underway in Hemble Drive in Kingswood. As part of a £100,000 scheme, four roadside gully drains in the street will be disconnected from the main sewer and instead linked to a new natural water storage area set to be created in an adjacent woodland.
The woodland – variously known as Midmeredales or Millennium Wood – was planted just before most of Kingswood was built. It’s now relatively mature but the flat clay ground it stands on means flooding already happens on a regular basis during wet weather, damaging trees and making public access almost impossible at times.
Hiatt Jackson, senior flood risk management officer at Hull City Council, explained: “The woodland is a valuable resource for the local community but it is prone to flooding. When complete, the water will enter the woodland through a surface channel, called a swale. This will look like a long depression in the ground and will be home to wildflowers and reeds. The wetland will use nature-based solutions to completely clean the water of contaminants and will store some of the water for most of the year, providing valuable habitat for amphibians, invertebrates, birds and plants. Any overflow from the wetland will travel along another swale and towards an old agricultural surface channel that empties into Wawne Drain. Water will only travel along this path in very large storm events or during very wet years. This system will reduce flood risk in Kingswood and help the green space to empty during wet weather which will help the woodland to maintain long-term health.”
A second phase of the scheme will see the installation of a new trash screen and a set of steps on nearby Foredyke Drain to help keep the watercourse clear of littler and free-flowing. Rather than using concrete, an earth embankment will be constructed at the site to provide access.
Hiatt added: “Concrete has a very large carbon footprint, so we are aiming to use less of it and to use innovative techniques instead to ensure bank stability and create operational assets that will last for a minimum of 30 years. This watercourse suffers from a high degree of fly-tipping and litter, largely shopping trolleys and drinks bottles and cans so we are hoping that ongoing work with local schools helping to educate young people on the importance of our open watercourses in providing flood resilience and wildlife habit really has an impact.”