The lower reaches of the Wandle from Earlsfield downstream to the Thames are highly urbanised, with long stretches where public access is difficult (even the Wandle Trail has to follow the road rather than the river for a long distance from Trewint Street to King George’s Park).

Most of the lower river’s course is heavily canalised, with sheer concrete or sheet steel piling banks that offer very little refuge for fish in high, flashy urban flows.

At the mouth of the Wandle, a mid-20th century tide weir has now collapsed and is being removed, but a small number of historic barriers to fish passage still remain.

One of these is at Trewint Street, on the site of an old gunpowder mill, where the Wandle Trust is collaborating with the Environment Agency to fit fish passage baffles to a complicated concrete structure.

Current and future projects:

• Trewint Street weir fish pass