The Culter burn is the second largest tributary of the Dee catchment, draining 151 km2. For at least 200 years, this habitat has been blocked to migrating fish – salmon, sea trout and lamprey – by a 6 m- high dam located 1 km above the confluence of the tributary with the Dee. Removing this dam, or making it passable to fish, is a challenging task, requiring money and engineering expertise.
One of the tasks of the Project Biologist is to assess the 125 km of tributary length above this dam and determine its potential to support stocks of fish. Due to agricultural and industrial impacts affecting this tributary, in some areas at least, water quality and instream habitat is severely degraded. To predict the likely increase in fish populations if the dam is made passable to migratory fish, we must incorporate measures of habitat quality into our estimations, and subsequently our ability to improve degraded habitat.
The Project Biologist’s assessment will demonstrate the expected benefits to fish populations if the dam is removed. Engineers will be bought on board to help us design an optimal solution to enable fish passage and these costs can then be weighed. There are several other dams on the system that will also be addressed in the assessment. The Trust will then have a finalised plan to see the restoration of the Culter burn through to completion.