On behalf of the Zoological Society of London (ZSL) and The Environment Agency, a company caled Frog Environmental has designed a revolutionary new eel pass structure to allow juvenile eels, also known as elvers, to travel through the weir alongside Osterley Lock on the Grand Union Canal in West London.
Leela O’Dea, Technical Director for Frog Environmental, explains: “This totally new and bespoke structure will be the final piece in the jigsaw enabling more baby eels migrating along the River Thames to reach the freshwater environment of the River Brent, where they can feed and grow to become adult eels.
“Sadly the previous eel pass installed two years ago wasn’t strong enough to withstand the force of the water and debris passing over the weir alongside Osterley Lock, the final barrier to overcome on the Grand Union Canal before it connects with the River Brent.
These creatures undertake the most incredible journey in the hope of reaching freshwater where they can thrive and grow, so it’s vital that we enable them to complete the very last section of that journey by installing successful eel passes.
With strength in mind and to avoid a further failure, the inner structure of this new eel pass is made of a single piece of polypropylene, an extremely strong plastic that is both chemically and heat resistant. Reinforced with steel it offers deflection and better protection from trees and other debris moving through the weir.