The structures will help various species of fish to swim upstream to spawn
A series of panels costing £180,000 are to be installed in a Devon river to help fish swim upstream to spawn.
The Environment Agency is installing three types of panels to allow various species to bypass a large weir on the River Culm at Silverton near Exeter.
Structures are being incorporated into the river to interrupt the current and slow it down to enable salmon and sea trout to swim upstream in stages.
Panels are being added to help eels and lampreys access the upper river too.
Special plastic panels with bumps on their surface are being added around the edge of the water to assist eels while the addition of stainless steel plates will help lampreys navigate the weir using their sucker-shaped mouths.
Coarse fish such as perch, roach and chub are also expected to benefit from the structures to reach new spawning grounds upstream.
Kevin Woodley, from the Environment Agency, said: "This scheme will open up previously inaccessible stretches of the River Culm to a wide range of fish species and should achieve some major environmental gains and benefits.
"We are hoping to see a significant rise in the fish population as species colonise new areas and have greater breeding success."
The work is being funded by Defra and supported by the National Trust which owns Silverton Mill and the adjoining weir.