Avon Barriers Project, South Lanarkshire

Product: Heidelberg Materials ColourCrete 

Client: Rivers and Fisheries Trust of Scotland (RAFTS)

Volume supplied: 200m³

Overview: Heidelberg Materials supplied coloured concrete to produce 200 ‘Lego’ blocks that were used to construct fish ladders as part of the Avon Barriers Project in Scotland.

Project description

Scotland has long-harnessed water energy through weirs and other structures. Although power is now largely sourced from other industries, many of the weirs still remain, preventing fish species such as salmon from migrating upstream to their natural spawning areas.

Two abandoned weirs on the Avon Water in South Lanarkshire – Ferniegair and Millheugh – were identified by the Rivers and Fisheries Trust of Scotland as particularly obstructive to fish, as they close off large areas of riverbed.

Following a feasibility study carried out by design and project management consultants Atkins Ltd, the preferred option for opening up these inaccessible areas to spawning fish was through the construction of fish ladders.

As a result, Blockwalls was chosen to supply its Stackabloc heavy duty interlocking wall blocks to form the fish ladders. The blocks needed to blend with the clay riverbed and, after a series of trials, Heidelberg Materials ColourCrete was specified as it provided the best colour match.

Bob Evans, managing director of Blockwalls, said: “The quality of the coloured concrete supplied by Heidelberg Materials was spot on and the support we received from the technical team ensured that the production of the blocks went very smoothly. The 200 two-tonne interlocking blocks have been used to great effect to create the new fish ladders, which have resulted in around 200 kilometres of river being opened up to spawning fish.”