The Traffic Impact Assessment prepared by AECOM discusses the traffic impacts associated with the Project.
The methodology used for the traffic impact assessment included:
- Collation and analysis of relevant traffic data;
- A review of proposed access to and within the wind farm site;
- Identification and review of construction traffic transport routes from ports and on local routes to the Project site;
- Over-dimensional swept path assessments to identify access mitigation measures and any native vegetation removal requirements (subject to detailed design); and
- Consultation with Regional Roads Victoria, Latrobe City Council, South Gippsland Shire Council, and Baw Baw Shire Council.
Legislation and Policy
The Key legislation and government policies considered in the preparation of the Assessment are as follows:
- Roads Management Act 2004;
- Victoria Government Gazette – Road Management Act 2004, Code of Practice, Worksite Safety, Traffic Management 2010;
- Department of Transport (VicRoads) – General Guidance;
- Department of Transport (VicRoads) Heavy Vehicle Network Maps in Victoria;
- National Heavy Vehicle Regulator (NHVR) website / journey planner;
The proposed site is bisected by the Strzelecki Highway (B460) that links the Princess Highway (M1), via Marrets Road with the project site. Local roads that will be used to access the site are Deans Road, Golden Gully Road, Smiths Road and Creamery Road – all from intersections off the Strzelecki Highway.
Impacts and Mitigation
Wind farm developments typically consist of three stages: construction, operation and either re-powering or decommissioning.
A total of 12 site entrances are proposed to the Project site from the public road network for heavy vehicles. Wind turbine and terminal station components are expected to be delivered to the site via Princes Freeway, Marretts Road and Strzelecki Highway using the existing Over Dimensional route before turning off at key local intersections at Golden Gully Road, Smiths Road, or Creamery Road for the wind turbine components and Deans Road for the terminal station infrastructure. Some intersection upgrade works will be required to accommodate the vehicle sizes needed to deliver wind farm components – Golden Gulley Rd and Smiths Rd require only minor temporary overturn hardstand upgrades, whereas Creamery Rd requires a major reconfiguration of the intersection. No upgrade works are required at the Deans Road intersection. Formal approvals for site access routes between the delivery port and site relating to height and weight of vehicles will be sought once a delivery port has been selected.
Aggregate for the project is expected to come from the Driffield Quarry on Smiths Road to meet the aggregate demands of the project, with concrete to be mixed at two temporary batch plants on Smiths Road before being transported to the relevant wind turbine sites.
General vehicle traffic will likely be concentrated during the morning and afternoon peak with staff arrivals and departures. 60% of construction staff are expected to approach and depart from the wind farm site along Strzelecki Highway from the north, and 40% expected to arrive and depart along Strzelecki Highway from the south. The Project is expected to employ 75 full time workers at its peak, therefore 75 light vehicle trips are expected during the AM peak. Even at peak volume, the traffic generated is significantly less than the typical one-way road capacity of 900 vehicles per hour and as a result the general traffic impacts are predicted to be negligible given the existing rural traffic volumes.
Vehicle movements associated with the operation of the Project will consist of daily maintenance activities and it is anticipated that up to 13 staff vehicles will commute per day to and from the site to undertake general maintenance activities.
Re-powering or decommissioning
The eventual decommissioning of the wind farm site will involve the removal of all above ground structures, excluding part of the foundations, sub-surface cables and access tracks. Re-powering the site would involve similar de-commissioning activities and the existing wind turbine components replaced with newer technology wind turbines and associated infrastructure. Similar vehicles as those used in the construction stage is expected in both instances, however the frequency would be reduced as no concrete batching plant would be required.
- Driver distraction: There is no clear conclusion from studies undertaken that wind turbines impact on driver safety. The potential for distraction from shadow flicker is mitigated by a high degree of natural shadow flicker or light variation along public roads due the extensive roadside vegetation in this area. Viewing areas are proposed to be provided to allow people to pull off the road to view turbines should they wish.
- Access and operating speeds: As a result of construction there will be an increase in slowing and turning vehicles on the public road network which could result in increased risk of vehicle collisions. These will be addressed as part of the TMP, with possible mitigation measures including increased signage, reduced speed limits and widening or overtaking lanes if required.
- Noise and dust: Construction traffic can generate noise and dust, which will require mitigation measures to minimise environmental impacts. These would need to be addressed as part of a Construction Environmental Management Plan.
- Adverse weather: Adverse weather conditions carry increased risk to road users during the construction period with RRV noting the area can be subject to heavy fog at times. Considerations to manage this risk might include a change in working hours and other possible measures which will need to be included in the TMP.
Typically on wind farm projects, any planning permit that is issued will include a condition requiring a Traffic Management Plan. Accordingly, a key further action in relation to traffic and transport matters will be the preparation of a TMP, in consultation with key stakeholders. A TMP is usually developed once a contractor has been commissioned to construct the Project. In parallel with the preparation of the TMP, there is a need for concept plans and mitigation measures to be prepared for road and intersection design development, in conjunction with RRV and relevant Councils.