Fish & Elver Passes
Martin Childs Ltd are constantly developing and improving our range of fish friendly products to enable the movement of migrating fish and elvers over and around water control structures. We strive to find solutions for the many different problems whether they are aggression of the tide, heavy silt deposits or general debris build up, there is always another situation awaiting a solution.
MCL manufacture various types of Fish Friendly Flap Valves, based on the standard top hinged flaps and side hinged saloon door flaps, that allow the movement of fish through the structure over a longer period before sealing off the flow of water up stream. On larger flap valves more than one fish flap can be fitted increasing the window of opportunity even more.
Depending on the speed of the flow of water, the rate at which the flap closes up can be controlled by sliding the floatation tank up or down the flap and by adding or removing ballast to the floatation tank. This combination provides the maximum time for fish to migrate and not pose a threat of flooding up stream.
To allow eels and elvers to travel up stream MCL have produced the Elver pass which can be fitted to concrete walls over a weir, or where there is a tilting weir, a self-regulating elver pass can be installed. This is adjustable with the use of floating tanks to allow the right amount of water to trickle through the substrate to encourage the elvers through the bristles and up stream.
Where there isn’t a natural flow of water a small pump can be installed to create the gentle flow required. These can be powered by mains electricity or, in remote situations, wind or solar power could be utilised.