Roadford Reservoir Mitigation Project in Cornwall

A summary of one of the Conservation Awards finalists: 

The construction of Roadford Reservoir, in Cornwall’s Tamar catchment, led to the loss of natural flows, spawning areas and habitat for all wild salmonid life stages; for over 30 years, compensation from South West Water took the form of a fish rearing and stocking programme. This project, however, a collaboration of Westcountry Rivers Trust, South West Water and the Tamar & Tributaries Fisheries Association, aimed to work on habitat improvement across the entire catchment, dividing it into three parts: the Lyd, the Inny and the upper Tamar. A suite of interventions has been implemented, including the reduction of abandoned coppice, gravel cleaning, debris dam removal and electric fishing monitoring.

The project has mapped areas for rehabilitation through 11km of walkover, established 16 new electric fishing monitoring sites, cleaned gravel at 65 sites (approx. 1,300 m²), thinned abandoned coppice on 27 sites along 3.8km of river to increase light penetration to the river and tackled six impassable debris dams. The aim, exceeded by more than double, was to increase smolt output by nearly 4,000 fish, excluding any increased migration from the debris dam work. 

A major feature of the project has been a shift in focus from the hatchery to habitat improvement, benefiting not only migratory salmonids but also those that stay at home and the entire river ecology. Monitoring is ongoing and is key to demonstrating the impact of the work. WTT judges appreciated the whole ecosystem habitat approach of this project; many species (of fish and other organisms) are benefiting, trout perhaps most so. The messages gleaned from this project will hopefully influence management practice across the West Country, precipitating less interest in hatcheries to attempt to support fish populations. 

Roadford project comp