KWT Fish Pass
The KWT Fish Pass is used when tilting weirs, stop boards, penstocks,
sluice gate
s or a dam structure blocks fish to return to higher waters. Usually, such Fish Pass is incorporated into a KWT tilting weir, overshot-, undershot- or sluice gate to form an integrated and fish-friendly flow control device.Application
Every fish require a different fish pass. For that reason, KWT developed several designs to accommodate a variety of fish, like Elver, Salmon, Trout and other natural water fish. In all cases, a continuous flow of water stimulates fish to swim upstream, regardless the differential head of both sides of the sluice gate or dam.
Design variations
KWT Fish Pass will be designed according to available requirements and is therefore always bespoke.
KWT supplied the following designs over recent months:
- De Wit boxed fish pass: a large box structure (illustration below left and picture above right) consisting of individual chambers. It is used when the differential head is limited as well as in shallow waters, generally in a fairly flat country side. The De Wit fish pass can be made from stainless steel, HDPE, or pre-stressed concrete.
- Elver pass: a fish pass dedicated to Elver (young eal) made from stainless steel and a rough green brush.
- Salmon / Trout pass: straight stainless steel construction with V-shaped ribs that generate a wild water effect.
Read the UK Environment Agency's Innovation Briefing #10 on fish friendly flap valves designed, manufactured and supplied by KWT International.
