Calder Highway Capacity and Safety Improvements Project

The Calder Highway Capacity and Safety Improvements Project was located within the city of Greater Bendigo. At the time of the project, the most direct access to Maiden Gully from central Bendigo was via Marong Road/Calder Highway. Rapid residential growth was occurring to the west of Bendigo and there were concerns over the capacity and safety of the section of Marong Road between Ironbark and Maiden Gully.

VicRoads engaged Octave Acoustics to carry out a noise impact assessment for the project. This assessment was required to determine traffic noise impacts and identify potential mitigation measures associated with the proposed works. Noise monitoring was undertaken at seven locations adjacent the project corridor. The results of this monitoring were used both to assist in defining the Project Objective Noise Levels (PONL) and to validate/calibrate the traffic noise model developed for the assessment. Model validation involved the comparison of model/calculation results for the current year (2019) with the results of noise monitoring. This process indicated an excellent level of correlation and hence the noise model was determined to to be validated and robust.

The input parameters to the noise model were then amended to reflect the Design Year 2031 (being ten years after the opening of the project) under two scenarios:

  1. The project had not proceeded (Do Nothing)
  2. The project had been completed (With Project)

The results of the Do Nothing scenario were then used to finalise the PONL and then the ‘With Project’ scenario was run. Results of the ‘With Project’ scenario indicated no instances of PONL exceedance. The lack of instances of PONL exceedance was not surprising as the goal of The Project is to reduce network congestion without increasing the road width significantly, by making improvements to intersections along the road corridor.

Modelling results showed that 27 residential dwellings were expected to receive traffic noise levels above the criterion that triggers the VicRoads Retrofitting policy. However, as the road was constructed before 1979 and is not classed as a Freeway, the policy did not apply in this instance.

As such, was determined that no noise mitigation measures were required as part of the project.