Work has started on the $110 million Mandurah estuary bridge duplication, which is aimed at easing traffic congestion and reducing travel time.
Construction started this month on building a second two-lane bridge and 4m-wide shared path on the south side of the existing bridge.
Vegetation has been cleared in areas designated for construction and project staff are holding geotechnical testing.
Road surveying and testing of the existing pavement is being done at night, with lane closures in place.
Passersby might notice activity in the estuary, with cone penetration testing (CPT) occurring to discover the soil properties below the estuary floor, which will assist in preparing the detailed design for the piles to support the new bridge.
A barge carrying the CPT rig will be launched from Mariners Cove boat ramp. Main Roads has warned parking and access at the boat ramp may be congested on the days when the barge is launched and collected, with traffic management in place during these times.
A fenced site compound is also being built on the north-east corner under the bridge, restricting access under the bridge via the footpath. Pedestrians have to detour via the lights at Leslie Street.
The picnic table on the south-east corner of the bridge will also be closed during construction and part of the median along Waterside Drive and three car parking bays will be removed.
The Federal and State governments are each contributing $55 million for the project, which is being delivered by Georgiou Group.
The bridge is expected to be finished in early 2026.
State Transport Minister Rita Saffioti previously said the bridge duplication would help commuters get home quicker and more safely.
“Duplicating the bridge will significantly ease the congestion currently experienced on approach to the bridge and cut the travel times for the thousands of commuters every single day,” she said.