Across the world, water barriers such as dams have caused a significant decline in freshwater fish stocks over the past 50 years.
Dams interfere with the reproductive cycles of fish by preventing them from migrating to their spawning destination. Now, some engineers at UNSW Sydney have come up with a brilliant invention to tackle this problem. It's called the Fishway tube, and in fact it's a real highway for fish to pass over the dams.
A brilliant invention
If we could reconnect our rivers and give fish the ability to navigate them safely, we would see more reproductive and healthier native fish populations in our rivers.
This is why the Fishway tube can hit the mark. This device works by pumping fish at high speed through a tube that runs over any dam or weir barrier to get the fish safely into the water on the other side.
An aquatic causeway
“The global population of freshwater fish has declined by more than 80% in recent decades. This is partly due to the hundreds of thousands of dams, weirs and barriers that block their movements,” he says in a release the professor Richard Kingsford, Director of the Center for Ecosystem Science, UNSW School of Biological, Earth and Environmental Sciences.
Fishway: economical and ecological
The device guarantees the protection of the fish by pumping a sort of "water cushion" which transports it quickly and without trauma. The invention is inexpensive and environmentally friendly, as it requires very little energy.
Another important aspect of Fishway is versatility which makes it easily adaptable to various local environments.
“Our numerical modeling work shows that this system will work reliably for pipes at least one meter in diameter, lifting fish more than 100m high. This is potentially a game changer in the ecological management of large dams,” he said Bill Peirson, Assistant Professor at UNSW Engineering.
The first tests were not easy: Fishway does not yet work very well with too high differences in altitude, and the team tries to perfect the invention for a "softer" journey without too many traumas.
The principle is nice: “There's no reason,” says Peirson, “why we can't have both healthy river systems and dams or other systems together. water basins functioning."
