Coarse fish and salmonids like brown trout will have access to more of the river, helping link up isolated fish populations and making spawning easier. Improvements have also been made to the habitat, providing fish and invertebrates a refuge from high flows and predators.
This work will help boost fish populations and benefit the wider ecology of the river.
Previously, fish could swim freely up the 14km of the River Witham from Stamp End in Lincoln to the Aubourn weir south of the city. But now that the weir has been removed and a fish pass installed, they can also swim up the next 20km between Aubourn and Claypole.
Nearly 1,000 tonnes of stone – mostly Leicestershire granite – was used to complete the rock ramp, considered the best and most natural means of passage at this location. Boulders and carefully-placed smaller stones form bars across the channel to make it easier for fish and eels to get upstream, with three rows of piling keeping the stone in place.
Environment Agency Fisheries Officer Matthew Parr said:
This fish pass will help increase the number and hopefully the variety of fish within the river system and boost the ecology, helping us achieve more for wildlife and the environment.
We’ve worked very closely with the local angling club, using their expert knowledge to create 15 areas of new habitat over a kilometre stretch of river, including in-channel berms, deeper pools, and woody material to provide shade and cover. These will also increase the overall health of the river.
It’s timely that we’ve finished it the week before World Fish Migration Day, which falls this Saturday, 21 May and aims to highlight the work going on around the globe to help migrating fish.
To mark World Fish Migration Day, the Environment Agency has revealed that more than 20,000km of England’s rivers have been opened up to improve fish migration over the last four years – the equivalent distance of London to Rio and back.
Notes to editors:
World Fish Migration Day helps raise awareness of the importance of open rivers and migratory fish and takes place on Saturday, 21 May 2016. You can find out more on the event’s website.
The £100,000 project took 3 months to complete and was installed after the Aubourn weir, which serves no flood defence purposes, was decommissioned.
The project was completed by Environment Agency framework contractors Balfour Beatty (in conjunction with their sub contractors A&V Squires, WaterCo and Forest Farm Tree Services).