EA project to save fish from saltwater flooding

The saline incursion management project is centred on streams near Ludham on the Norfolk Broads, where Environment Agency and Anglian Water staff are helping thousands of fish that are forced into small waterways when saltwater floods their natural habitat.

Stephen Lane, EA Technical Specialist, Fisheries, discovered that thousands of bream, roach and perch were getting trapped at Womack Water, which runs from a dyke off the River Thurne.

“North westerly winds and tidal surges push the salt water a long way inland. If it stays up long enough, it can trap and kill fish in dead ends. We needed a source of raw water that we could use to pump in there, to dilute the salt and create a little freshwater refuge area,” explained Stephen.

He approached Anglian Water for help and found they have a pumping station directly opposite the ditch, which pumps foul sewage from the catchment to the treatment works. The treated final effluent from the works then gravitates back to the pumping station where it’spumped to Womack Water to a discharge point.

As the quality of the effluent is superb, Anglian Water agreed to install an electric pump in the final effluent sump, to which they connected some piping. They can run this across the road and into the ditch whenever it’s needed.

“We’ll be able to turn the pump on and monitor the salt levels to see how the fish respond. It’s a novel idea that could help to provide valuable refuges for fish at other critical sites within the Broads,” added Stephen.