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Hydro Tasmania announces Australia’s first eel bypass for downstream migration

Hydro Tasmania announces it will install an eel bypass in its Trevallyn Dam to allow the downstream migration of short-finned eel (Anguilla australis), which travel from the Tamar Estuary to spawn in the Coral Sea near New Caledonia.

Hydro Tasmania Chief Executive Officer Steve Davy said World Nature Conservation Day on July 28 is appropriate for announcing this initiative because the day is about raising awareness of best practices for the protection of natural environments and habitat.

“Hydro Tasmania is Australia’s largest water manager and Tasmanians expect us to look after the waterways under our care, and that includes protecting the species we’re sharing these areas with,” Davy said. “Though not endangered in Australia, similar species of eels are listed as threatened in the Northern Hemisphere, so the responsibility is on water managers like Hydro Tasmania to take action.”

Trevallyn Dam, on the South Esk River in Launceston, was commissioned in 1955 and diverts water for a 95.8-MW powerhouse that operates in run-of-river mode.

Hydro Tasmania first installed an eel ladder at Trevallyn Dam in the 1990s, for upstream migration of juveniles, according to aquatic scientist David Ikedife. “Until now, their annual downstream migration has relied either on the dam spilling, or the eels trying to pass through the Trevallyn Power Station intake.

“This is the first time any dam in Australia has been fitted with an eel bypass for downstream migration, so a lot of research and development has gone into this, and population numbers will be carefully monitored to see what effect it has.”

The new eel bypass will operate from December to April each year.