Remote crossing sets new record for M-Lock® bridge

The longest Rocla M-Lock® bridge in Australia (and the second longest in the world) was completed in WA.

The 456-metre long road bridge provides a reliable two-lane crossing over a flood plain near Carnarvon.

The Bibbawarra Road crossing replaces a gravel road across the dry bed of the Gascoyne River that is used by local traffic, tourists and the Aboriginal community at Ingada Mission.

Every time the river flowed the road was washed out, resulting in it being closed for as much as five months of the year and forcing a 34km round trip detour via the Gascoyne River Bridge.

Main Roads WA provided funding for the bridge, which is to be managed by the Shire of Carnarvon. The Rocla M-Lock® precast bridge system was adopted to reduce design and construction risks.

The 456-metre long bridge is 8.4 metres wide and includes 38 spans, each of 12 metres.

It is supported on 156 Rocla Duraspun® concrete piles, each 12 metres long and 585mm in diameter.

The bridge deck is set approximately 1.5 metres above the riverbed and includes precast castellated kerbing cast to the edge planks on every span. Bridge components were manufactured at Rocla’s Perth factory.


Project: Flood Crossing, WA

Location: Carnarvon, WA

Owners: Main Roads WA/Shire of Carnarvon.

Construction Contractor: Bocol Constructions

Design Consultant: Bruechle Gilchrist & Evans

Precast Bridge System: Rocla Pipeline Products

Spun Concrete Piles: Rocla Concrete Poles