Underwater Rock Barrier for Fremantle Inner Harbor
An underwater rock mound has been constructed in Fremantle Inner Harbor to protect the Fremantle Rail Bridge from the risk of ship impact, the Fremantle Ports said in its latest release.
The underwater rock mound is about 60 meters long and 20 meters wide. Rocks used for this project were a minimum of 20cm in diameter and pre-washed to minimize plume during placement.
“The highest point is visible only in some low tidal conditions. It is not located in the path of port vessels maneuvering in the harbor or commercial/recreational vessels travelling through the bridge spans,” according to the announcement.
The work began in early July and was completed mid-August.
The decision to install this barrier follows shipping incidents in 2011 and 2014.
The underwater rock mound is providing additional protection for the north-eastern section of the bridge.
The remaining sections are already protected by the Wongara Shoal and by structures installed in front of some of the bridge pylons by the Public Transport Authority and Main Roads WA.