Construction of Rock Ramp Fish Easement, Lower Darwen

Tender description

Blackburn's Rivers Important to Lancashire's Landscape and Natural Capital Economy (BRILLIaNCE) is an ambitious project supported with funding from the European Structual and Investment Fund to deliver physical improvements to the Rivers Darwen and Roddlesworth within Blackburn. We are seeking interest from suitable Civil Engineering Contractors to deliver the creation of a fish easement in the form of a rock ramp. Specifically the works are required to construct a fish easement on Lower Darwen Weir on the River Darwen. The weir is a high sloped horse-shoe concrete and stone weir. This is a barrier to the migration of fish such as trout and eels. The fish pass will be created by building a channel on the (true) left of the weir. An embedded rock-ramp will be constructed in the new channel, enabling fish to swim up and over the weir. The rock ramp will have a rough surface to create a turbulent flow. Access is expected to be off the B6231, and requires demolishion (and subsequent re-construction) of a boundary wall, and creation of a suitable access route to the weir.