Trevallyn Power Station was commissioned in 1955, replacing the Duck Reach Power Station. The construction village, named Marrawaylee, is now part of the suburb of West Riverside and is accessed by Pomona Road. The power station and the open land for the transmission lines now serves as a border between the Launceston suburbs of Riverside and Trevallyn.
The 3.3-kilometre (2.1 mi) long penstock pipeline for the power station runs underground for its entirety except for a short, 100-metre (330 ft)-long, portion that leaves the ground near Pitt Avenue due to a valley intersecting the tunnel's course. The pipeline splits underground into four smaller pipes immediately before entry into the station's turbines. The tunnel through which the pipeline runs is cut through dolerite and was excavated by a French tunnelling company. The bay that the used water is discharged into was excavated using mostly steam driven equipment and tram ways with the two tailing mounds now forming the Tailrace Park (south side) and the Tailrace Convention Center (north side). The Tailrace Bay has been adapted to serve recreational purposed and also provides a safe anchorage for yachts.