We were privileged today to enjoy a guided tour of the Louth Flood Storage Reservoir. As many locals will know the river Lud runs through the centre of Louth and has over topped it’s banks several times (1920, 68, 93 and 07) flooding adjacent homes and businesses. To reduce the risk of further flooding a pair of reservoirs have been created that limit the maximum flow of water through the two tributaries that form the Lud.
The flow of each tributary is limited by a float attached to a rotating disk of increasing diameter – a device know as a Hydra Slide. As the float rises the disk rotates reducing the size of the opening and a constant rate of flow is maintained even though the water pressure has increased. In this way the peak flow is reduced with excess water backing up and filling the reservoir. When the incoming flow of water reduces, the Hydra Slide will continue to govern it’s drainage at the same controlled rate until the levels drop and it can be de-activated.
The cost/benefit ratio for the project didn’t look good but by creating a partnership, local agencies where able to unlock the £6.5m required. Opened in July 2017 the reservoir was successfully activated on Easter Monday in 2018. For those at risk the likelihood of being flooded in any given year has fallen from 1:20 to 1:150, a very significant achievement.
Thanks to Paul Arnold, Peter Davenport and Keith Hughes-Marshall who guided us around the project and answered our many questions. Thanks also to Rotarian John Handley who was kind enough to arrange the visit.