The fish pass alongside the Victorian weir at Bevere, as one of the UK's rarest fish is getting the chance to return to historic breeding grounds on the River Severn which have been cut off by weirs for 170 years. PIc: PA ONE of the largest conservation projects of its kind will see a rare species of fish return to Worcestershire for the first time in 170 years – and you can help. The endangered twaite shad was cut off from historic breeding grounds in the city’s stretch of the River Severn through the installation of Victorian weirs. Now, the Unlocking The Severn project by the Canal & River Trust, Severn Rivers Trust, Environment Agency and Natural England is in the process of making available to the fish 150 miles of the river by creating routes around four major weirs.