FISH LADDER

Darebin Creek fish ladder in the Darebin Parklands in Alphington. A fish ladder, also known as a fishway, fish pass, fish steps, or fish cannon, is a structure on or around artificial and natural barriers (such as dams, locks and waterfalls) to facilitate diadromous fishes' natural migration as well as movements of potamodromous species.

Most fish ladders enable fish to pass around the barriers by swimming and leaping up a series of relatively low steps (hence the term ladder) into the waters on the other side. The velocity of water falling over the steps has to be great enough to attract the fish to the ladder, but it cannot be so great that it washes fish back downstream or exhausts them to the point of inability to continue their journey upriver.

Carried out by Melbourne Water, the $350,000 project in Darebin Creek involved installing a series of carefully designed rock works placed downstream of the structure in Darebin Parklands. This ‘rock ramp fishway’ allows water to cascade through the structure forming eddies that act as a refuge for fish so they can move freely through the waterway.

The design targets fish species that migrate from saltwater to freshwater environments to complete their life cycle including Common Galaxias and Short Finned Eel. The fish ladder was constructed with imported locally sourced rock. The project was constructed on site where materials were matched to complement the natural waterway and the environment.

This post is part of Roentare’s Water Meme

and also part of the Wordless Wednesday meme

and also part of the Nature Notes meme