Creamery Weir Removal: The Immediate Improvements for Migratory Fish

The dis-used Creamery Weir and sluice gate, at the Creamery Building on the Old Mill Burn, near Twynholm, presented a complete barrier to migrating fish species and was identified as crucial to improving the #aquatic ecology and long-term #ecological gain of Old Mill Burn and Tarff water in Dumfries and Galloway.

The aim of the engineering work

In 2016, Ebsford Environmental Ltd carried out in line with the SEPA and RAFTS objectives to improve fish passage along the watercourse by removing the old unused weir and restoring a more natural #river channel. For fish such as Atlantic salmon, sea trout and lampreys, free passage between the ocean and freshwater environments is an essential part of their lifecycle for breeding and spawning.

Removing obstacles

Obstacles that block these migration routes therefore helps the recovery of damaged fish stocks, while also preserving the natural ecology of Scotland’s watercourses. Specialist works carried out by Ebsford’s water civils team included the removal of the redundant three metre high Creamery Weir and associated sluice gate, and the installation of an engineered rock step-pool sequence. The works were completed under close supervision to protect the original geomorphology of the burn.

Connecting path and watercourse

Once complete the clear path once again connected with the main watercourse allowing for the free and safe passage of all aquatic species of interest in long-term ecological gain for the area. By removing the fish barrier around 10 km of river was once again made accessible to native migrating fish.

In 2017, during the first year of post-work monitoring, salmon were found in one of the two sites electro fished upstream of the demolished weir site, (indicating that successful spawning of wild salmon had taken place during the winter of 2016). Salmon were also found within the single electrofishing site fished downstream of the creamery weir site in 2017.

Client satisfaction

Comments from client Rob Mitchell from RAFTS said: “Migratory fish species such as salmon and sea trout are under pressure due to a number of different factors. In the river environment, increasing and improving habitat is the most effective way to increase juvenile production.

The easement or removal of barriers to fish migration such as the Creamery Weir is a very effective way to enable access to otherwise inaccessible habitat. Francis Hayes from SEPA’s Water Environment Fund said: “The Creamery Weir Project is an exciting opportunity to allow salmon, sea trout and other native fish species to once again access river habitat upstream. It is an example of work happening across Scotland to help achieve our objectives set out in the River Basin Management Plan.”