Lead Brook runs into the River Dee where it reaches the sea. It is currently fragmented by a reservoir which impacts the migration of elvers upstream into the headwaters of the brook. To improve their chances of successfully migrating upstream, reservoir spillway retrofit is required.
Eel pass will span approx. 200m
Design a low maintenance eel pass that would help elvers to migrate upstream along the reservoir spillway and obtain consent from NRW.
A site visit was conducted with NRW and Essity Ltd to discuss potential options for eel passage at the beginning of the project. After a consensus was reached on the best way forward, we prepared outline designs for a mussel spat eel pass and constructed a prototype to aid in the constructability of the design. The outline designs were reviewed by the client and the Environment Agency and NRW were consulted throughout, building on their experience of mussel spat rope eel passes to ensure that the design was as effective as possible. The Eel pass is made of multiple strands of mussel spat rope to create a low flow route along the edge of the spillway which will vegetate up and provide a safe passage route.
Construction issued designs including buildability statement and designers risk assessment. Consent from NRW.