Challenge

Consultants Atkins conducted a feasibility study into the viability of a flood defence scheme for the River Lud at Louth.

Two online flood storage areas were identified and the volume of storage would be dependent on the method selected to control flows.

The design of the project required a balance of two factors: maintenance costs and storage volume.

Using options with no moving parts such as fixed weir, orifice and vortex type flow controls, which solely limit the flow, would result in increased storage, but have very low maintenance costs. Low storage volumes can be achieved through the use of mechanical and electrical systems, however these would have maintenance costs and potential reliability issues.

Solution

The consultants accepted that there could be some moving parts within the solution, and therefore maintenance, and this allowed ELIQUO HYDROK to install, as the right solution, a HydroSlide® flow control.

A HydroSlide® consists of seesaw on a pivot with a plate at one end and a float as the counter balance at the other. As the water level increases the float rises causing the plate to close across the orifice opening and restricting outflow.

Although it has a moving part, the discharge curve holds tightly to the optimum discharge +/-5%.