Below are photographs of a new combined canoe and fish pass at Porters Lock on the River Medway in Kent. The pass is the first of its type in the UK. It is located approx 3 miles West of Tonbridge. The structure is based on a German design that uses artifical reeds known as "fish brushes" fixed to a 1.5 metre wide steel channel on a 1 in 12.5 slope. 1 in 12.5 is the maximum gradient that this type of pass can successfully operate at.
Quite simply the fish brushes are designed from Recycled plastic that is flexible enough to allow canoeists to glide over the top of the them and yet rigid enough to create back-flows and eddies which allow fish to traverse the pass upwards.
As you can see from the photographs, there was a simple fixed crest weir at the head of the channel. This was demolished and in its place a steel channel was designed and fabricated by Hunton Engineering, with installation assistance by Breheny Civil Engineering. The total cost including design, construction and supevision was £94k.
For any further techincal information on brush passes please contact Chris Downs at Halcrow on 01732 424184.
For further information on the design of the steel channel and supporting structure please contact Sean Trow at Hunton Engineering 01622 820643.
The fish pass is located here
The design
Photos below.
The following photographs show the construction of the pass:
For further information on canoeing on the Medway click here
Below are photographs of the new portages the Environment Agency have installed at 3 sites on the Upper Medway in early 2009.
TONBRIDGE LOCK UPSTREAM
TONBRIDGE LOCK DOWNSTREAM
EAST LOCK UPSTREAM
EAST LOCK DOWNSTREAM
OAK WEIR LOCK UPSTREAM
OAK WEIR LOCK DOWNSTREAM
For further information on canoeing on the Medway Click here
