Siphon fish ladder The FishFlow siphon fish ladder is an innovative Principle and cost-effective fish way, which can be applied The FishFlow siphon fish ladder consists of a at dams, weirs, sluices and pumping stations to conventional fish ladder that is placed inside a facilitate fish migration. Many waterworks closed box. Partitioning walls have been placed in obstruct the migration of fish by blocking or the box to create a series of compartments. In the restricting the connectivity between adjacent siphon fish ladder a vacuum pump raises the water water bodies. The siphon fish ladder can be applied until it spills over the partitioning wall between the to restore fish migration routes and contributes to the development of more natural fish stocks. The upper compartments in the fish way and water starts fish way can therefore be used to effectively flowing through the fish way. The vacuum pump will improve ecological conditions and can contribute subsequently control the volume of air that is present to the achievement of the goals set in the in the system. The volume of the air bubble defines European water framework directive. the water flow over the fish ladder. FishFlow Innovations Dissel 4 1671 NG Medemblik, the Netherlands telephone 0031 227 570 020 fax 0031 227 547 356 www.fishflowinnovations.nl Siphon fish ladder Advantages Monitoring results Key characteristics of the FishFlow siphon fish ladder The first FishFlow siphon fish ladder was installed on are: a weir in the river Hertogswetering in the Low water consumption. Local water availability Netherlands in 2006. Upstream migration through is used as a guideline for dimensioning a fish the fish ladder has been monitored during one year. ladder. The siphon fish ladder can function star For this purpose a fyke net was attached to the ting at a flow rate of several liters per second upstream end of the fish ladder. Adjustable flow rate. The flow rate can be adjusted to suit existing needs Over 88 days a total of 612 fishes representing 11 fish Low energy requirement. In the siphon species were caught. Perch, roach and gudgeon were construction there is no need for water pumps, most abundant in the total catch. Species with lower which results in a low energy requirement swimming abilities (spined loach and gudgeon), Flexible positioning. The fish ladder is a crayfish and tadpoles were also found to have prefabricated system that can be placed in any successfully passed the fish way. The length of the position (near, on top, above or inside) in a caught fish varied from 4 to 67 cm. The length migration barrier or in a levee frequency distribution that was found was similar to Low maintenance. The system is easy to the distribution found during a fish stock assessment maintain and is fitted with shutters in the in same river in 2003. Fish passage outside the partitioning wall that allow flushing of the fish typical seasons for fish migration showed that fish ladder to prevent the accumulation of sediment easily migrate through the fish ladder and no longer and debris consider the weir a migration barrier. Flexible design. The design of the FishFlow siphon fish ladder can be adjusted for integration species total catch percentage length in the landscape or to suit decorative or of catch range educational purposes. Additions such as the bleak 8 1 % 4-14 installation of a viewing window or a fish counter european perch 163 27 % 6-17 are optional bream 48 8 % 9-42 Cost effective. In comparison to conventional roach 153 25 % 5-15 fish ladders the costs of the construction of the FishFlow siphon fish ladder are estimated spined loach 35 6 % 4-10 to be at least 50 % lower river gudgeon 168 28 % 4-16 Provides passage to a large variety of fish pikeperch 1 0 % 32 species, including bottom-dwelling species. pike 1 0 % 12 white bream 1 0 % 5 tench 1 0 % 5 european eel 33 5 % 20-67 total 612 4-67 FishFlow Innovations Dissel 4 1671 NG Medemblik, the Netherlands telephone 0031 227 570 020 fax 0031 227 547 356 www.fishflowinnovations.nl Siphon fish ladder FishFlow Innovations FishFlow Innovations develops and produces innovative products to facilitate fish passage and fish deflection. In addition to strobe lights, FishFlow Innovations produces: Airlift (to prevent cyanobacteria) Eel ladders Siphon fish ladders Fish-way for pumping stations Fish-friendly pumps and hydro turbines Rotary drum screen for cooling water intake Bypass-systems For more information on the strobe lights or our other products, please contact us via [email protected] or visit our website www.fishflowinnovations.nl/en FishFlow Innovations Dissel 4 1671 NG Medemblik, the Netherlands telephone 0031 227 570 020 fax 0031 227 547 356 www.fishflowinnovations.nl .