Why was the assessment undertaken?
Transportation associated with construction and operation of wind farms can impact on local and regional road networks.
A Traffic Impact Assessment (TIA) (contained at Appendix G.7 of the Modification Application Report) was prepared by SMEC to consider the change in potential traffic and transport impacts as a result of:
- Selection of the Preferred Transport Route via the local road network
- Consideration of three over-dimensional and heavy vehicle transport routes
- Modification of the wind farm development footprint, increase in the turbine size and reduction in wind turbine numbers that has influenced the amount of construction material, water and equipment requiring transportation to site
What was the approach?
The TIA was prepared considering the relevant conditions of the Development Consent and in accordance with the Director General Requirements for the Original Environmental Impact Statement (EIS).
What did we find and how does it compare to the approved project?
At the time the Development Consent was granted, a preferred transport route for heavy and over-dimensional vehicle traffic via the local road network had not been selected. The Development Consent authorises the use of several transport routes along local roads and as part of the Modified Project, we’ve selected a preferred route. This route is shown in the figure below.
A Preliminary Road Investigation helped us identify this route based on the condition of the local roads and potential impacts to native vegetation. As part of this assessment, we also identified sections of road we might need to upgrade.
The Development Consent considers the option for heavy and over-dimensional vehicles to be transported from Port Kembla. As part of the Modified Project, two additional route options have been considered (both from the Port of Newcastle). This is to allow greater understanding of the different options and give flexibility with the final selection of wind turbine, as different wind turbine suppliers have different preferences of ports. Whilst several modifications to roads and intersections would be required to accommodate over-dimensional vehicles, all routes are considered viable options.
Consistent with the Approved Project, the Modified Project will generate a large amount of additional traffic, particularly during the construction phase of the Project. Operational traffic is expected to be low, limited to operational staff carrying activities during standard work hours.
As a result of the 13% reduction of wind turbines from the Approved Project, the Modified Project is estimated to decrease heavy vehicle traffic generated during the construction phase of the project by 0.1%.
The 0.1% reduction is in comparison to the Approved Project where construction traffic generation has been re-baselined against the approved 92 wind turbine layout. The re-baselined figure of 33,031 heavy vehicle traffic movements reflects the actual traffic generation (based on improved assumptions and more accurate information) of the Approved Project, should it have been constructed.
What are the proposed mitigation strategies?
Measures to mitigate potential impacts to local traffic during the construction period will be outlined in a Traffic Management Plan (TMP) in accordance with the existing conditions of the Development Consent. The TMP will be prepared in consultation with the relevant road authorities (including Councils) to ensure that applicable and appropriate safety standards are achieved and disruption to local traffic is minimised.
Assessment against Development Consent
The selected Preferred Transport Route for over-dimensional and heavy vehicles along the local road network, and consideration of two additional transport routes from the Port of Newcastle is to form part of the Modified Development Consent. The Modified Project can comply with the existing conditions of the Development Consent relating to the preparation of a TMP.