A quarry-side cliff in Fremantle, Western Australia has been stabilised to ensure the safety of the state’s oldest building, the heritage-listed Round House.
The former Arthur Head quarry was used between 1833 and the 1960s to build much of Fremantle Port and the adjoining railway, but more recently it has posed safety issues to pedestrians and the adjacent Round House.
The Round House was the first permanent building in the Swan River Colony and originally opened as a jail.
The limestone cliffs at Arthur Head had been fenced off to pedestrians since 2018.
Stage two of the stabilisation works are now complete, with a limestone retaining wall in place to match a similar stage one job nearby.
Arthur Head project officer Paul De Young told the Australian Senior News the task was trickier than first imagined.
“Our original intent was to anchor the new limestone wall to the eroded cliff face and then backfill it with concrete, but when we started drilling the anchor points we discovered a large number of voids in the cliff and that the whole face was quite unstable,” De Young said.
“We revised the angle of the wall design to make it a gravity retaining wall, which we had to build layer by layer and then backfill with concrete as we went.
De Young said that the use of limestone as a nod to the area’s history also added difficulty to the job, as the slow-drying material was hampered by wet weather.
Stage three of the project will now begin on a new rockfall canopy above nearby Whalers Tunnel, as well as similar cliff stabilisations.
The project has received $500,000 each from the City of Fremantle Council and the state government, but any works past stage three are subject to further funding.