Transport for NSW proposes to widen Bridge 152 over the Woronora River (referred to as the Heathcote Road bridge) and its approaches (the proposal). The proposal is located about halfway along Heathcote Road between New Illawarra Road in Lucas Heights and Princes Highway in Heathcote, New South Wales (NSW) within the Sutherland Shire local government area (LGA). Key features of the proposal include:
• widening of the bridge by about 1.4 metres on each side to provide one wide 3.5 metre lane in each direction with 1.2 metre shoulders
• widening and adjustments to the northern and southern bridge approaches about 250 metres either side of the bridge to improve the road alignment, increase lane and shoulder widths and reinstate the existing breakdown bays either side of the bridge
• new bored-pile retaining walls to support the slope along both bridge approaches, which would be up to two metres high and range in length up to 100 metres
• slope stabilisation measures including rock scaling, shotcreting, rock bolting, rock netting, and vegetation removal
• new and modified drainage infrastructure including replacement and extension of existing cross culvert pipes on the approaches for the widened road pavement, improved drainage gutter along the base of the rock cuttings, new longitudinal drainage outlet at each abutment and scour protection at all discharge points
• adjustments to optical fibre conduits for the length of the proposal area
• repair and maintenance work to the existing bridge structure including: o repairs to cracks o replacement of all bearings o joint replacement o application of an anti-carbonation coating on the bridge structure including piers o installation of new steel maintenance staircase for side access to the bridge for bridge inspections
• other ancillary work required to support construction of the proposal including two off site construction compounds and establishment of a temporary access track, waterway crossing and crane pads
The proposal would require the full closure of Heathcote Road between New Illawarra Road and the Princes Highway for up to six months during construction due to the constraints of the location including the steep terrain of the surrounding area and narrow width of existing roadway. Construction is proposed to be carried out 24 hours per day, seven days per week to minimise the duration of full road closures required.
It is anticipated that construction would start in late 2021 and take up to two years to complete, subject to weather.