Underpass in the Southern Zone
9 Apr 2015

Underpass installation surpasses expectations

Expectations were surpassed when Gateway WA’s latest underpass was installed ahead of schedule, providing early access for motorists to the section of Roe Highway that had been closed last weekend.  

As part of the Gateway WA project an underpass is required for the Principal Shared Path network to cross Roe Highway, west of Tonkin Highway, in the project’s Southern Zone. In order to undertake the work safely, a section of Roe Highway had to be closed to all traffic over the Easter weekend.

There were a number of steps involved in the completion of the underpass at this location. The work began with traffic control set-up and detour implementation which was carried out on Thursday evening.

By Friday the team was focusing on bulk excavation and foundation work. This was closely followed by the installation of the precast concrete structures that form the underpass.     

Backfill and sub-base placement were next on the agenda with asphalting forming the last major step in the process. The road was re-opened in the early hours of Monday morning, well ahead of schedule.

A high level of co-ordination was required between the various disciplines working on the underpass installation, including civil, structural, traffic, asphalt, community, environment and quality teams.

The underpass provides connectivity for the 21 kilometres of Principal Shared Path that will provide improved facilities for cyclists and pedestrians in the project area.