Whooshh Fish Passage System (WFPS)
Contents
Quick summary
Date: 2019
Developed by: Whooshh Innovations, Seattle
Suitable for the following [[::Category:Measures|measures]]:
Introduction
Upstream and downstream fish migration is among the main concerns regarding ecological sustainability of hydropower schemes. For small weirs and dams conventional approaches such as various types of fish passes or natural bypasses are available. However, upstream migration over dams higher than 20 or 30 m is considered technically unfeasible and too costly. The Whooshh fish passage system (WFPS) is an innovative and highly cost effective method to enable upstream migration across dams of any height. The WFPS was designed using novel, innovative ecotechnology to allow autonomous, selective, volitional upstream fish passage over low and high head dams. The technology provides fish passage through the application of differential air pressure to glide the fish rapidly through a soft, flexible tube, with controlled deceleration and smooth exit. This provides safe, timely, efficient and effective fish passage.
The WFPS was originally developed and tested for Pacific Salmon. Salmon are excellent swimmers and actively enter the WFPS through a so-called false weir where they are dewatered and from where they slide into a scanner equipped with six cameras. For European rivers a different entry device was developed that uses a traditional entry structure, similarly like for other fishways, with multiple entrances, attraction flows etc. Once inside the entrance basin fish are eventually drawn into a Archimedes screw type fishlift which is lifting the fish out of the water, drains the water and lets the fish glide into the above mentioned scanner. For the entrance design some more options are existing. They are designed according to the local situation regarding topography and water levels, as well as to the different fish species to be enabled to migrate upstream.
Once in the scanner the fish is scanned and an artificial intelligence based system determines the size of the fish and the species. It can also differentiate between wild fish and hatchery fish if the adipose fin is removed from hatchery fish. The system then determines if the fish is to be transported upstream in one of the installed tubes, taken into a holding tank or back into the tailwater area (e.g. for preventing invasive species to migrate upstream). This is done by a system of opening or closing gates the fish glide through. The entire process of scanning and sorting takes 1-2 seconds.
From the scanner and gating system the fish are gliding into a so called accelerator where a gentle pressure difference of 0.1 bar is applied to move the fish into and along soft, water lubricated tubes of different size. The fish are moving in a mist of air and sprayed water with a velocity of several meters per second along the tubes. A distance of several hundred meters can be overcome and dam heights up to 300 m can be crossed. At the end of the tube the fish are gently released into the headwater and can continue their upstream journey.
Application
The WFPS is a modular and highly flexible scheme. It is custom designed for every individual site. The design and particularly the entrance solution is adjusted to the local situation, upstream and downstream water levels and their fluctuations and to the fish species that are to be enabled to migrate or blocked from migration. In European rivers where usually many different species are abundant that vary in size and body shape it is necessary to install several tubes with different diameters to allow sorting and transportation according to the shape and size of the individual fish. The combination with the Archimedes screw fishlift ensures that all fish species, including bottom fish and poor swimmers, can actively enter the WFPS. The Archimedes screw fishlift has demonstrated its capability to lift fish over a range of lengths and all species tested so far. A WFPS can be installed within months rather than years and it is considerably less costly than comparable traditional fish ladders such as vertical slot passes. Since only negligible flows of water are used for the operation, it may even pay for itself in situations where no environmental flows must be released, e.g. in hydropower dams where the power house is at the bottom of the dam.
Other information
So far around 20 studies have been performed to evaluate the effects of fish passage through the WFPS in comparison to passage through conventional systems such as vertical slot passes. The following aspects were investigated and no negative effects were detected:
- Short-term and long-term survival after WFPS passage
- Injuries and physiological stress
- Reproductive consequences (health of eggs)
- Energetic costs of migration
The results are published in peer-reviewed journals, governmental and internal reports. All information can be found on the Whooshh website, including links to several youtube films. The costs for the system depend on the site specific design, the entrance system, the length of transport and the number and size range of species and therefore the complexity of the sorting system and the number of tubes. Typically, the cost savings in comparison to a traditional, e.g. vertical slot, fish pass, reach up to 80% for higher dams whereas for dams around 12 m of height the costs are similar for both types of systems. The operating costs are caused by maintenance of the components and the energy consumption for the compressed air blower and other components such as pumps. In stand-by mode the system needs around 1 kW and as soon as a fish enters, the consumption rises to 20 kW. But that level of consumption is only needed for a few seconds until the fish has left the system. An energy cost per fish can therefore be calculated. On the other hand, the system requires hardly any water and therefore can be highly favourable and cost saving in comparison to a traditional fish ladder.
Relevant literature
- Geist DR, Colotelo AH, Linley TJ, Wagner KA, Miracle AL. 2016. Physical, physiological, and reproductive effects on adult fall Chinook Salmon due to passage through a novel fish transport system. Journal of Fish and Wildlife Management 7(2):1-16.
- Mesa MG, Gee LP, Weiland LK, Christansen HE. 2013. Physiological responses of adult Rainbow Trout experimentally released through a unique fish conveyance device. North American Journal of Fisheries Management. 33(6): 1179-1183.
- Fryer J. 2017. Results of a PIT tag study at Priest Rapids Dam to assess the impact of the Whooshh Fish Transport System on upstream migrating Sockeye Salmon. (April 2019; http://www.ucsrb.org/science-on-the-street-february-2017/)
- Hansen W. 2015. Whooshh Volitional Entry. (April 2019; https://www.youtube.com/watch?v=bFj-Fj5-bPY)
- Whooshh. 2018. Whooshh Study Results. (April 2019; https://www.whooshh.com/studies.html)
Contact information
Whooshh Innovations Ltd
Representative for Europe and the Himalayan region:
Dr. Klaus Jorde
KJ Consult
Klagenfurt, Austria
Tel.+43 664 2429748
klaus.jorde@kjconsult.net
