We have undertaken extensive field studies to gain an understanding of the environmental features, technical challenges and opportunities.
These have included:
- geotechnical and ecological surveys – to gather information about soil, rock and native habitats
- hydrology studies – to examine flooding and surface water movements
- noise, air quality and vibration surveys – to measure these levels at key project sites
- utility identification surveys – to identify infrastructure such as gas and water pipelines
- land and heritage surveys – to identify property boundaries and investigate any evidence of Aboriginal and non-Aboriginal artefacts and heritage
Site investigations, environmental assessments and field studies will continue to occur during this stage as we consult with landowners, councils and other key stakeholders. Field investigations and surveys will occur on public land, road reserves and the Queensland Rail corridor. Investigations on private property will be arranged on a voluntary basis with individual landowners. All investigations are weather permitting.
Crossing the Condamine floodplain
Since the release of the proposed Condamine floodplain crossing model and design in late 2018, we have continued consulting with landowners and key stakeholders to update the flood model and crossing design.
The flood model has been expanded to include additional local flow paths, in particular within the Back Creek catchment, and has been validated against the 2013 flood event.
Works have included:
- conducting further tests to determine how inflows from local creeks may impact water levels and velocities in a rare flood event
- improving our flood frequency analysis using additional data from the Warwick and Cecil Weir stream gauges
- gathering anecdotal data of historic flood events prior to 1921
While this work has improved our understanding, it has not resulted in any significant changes to the overall floodplain model or required us to make considerable updates to the crossing design.
Local community feedback has informed the proposed Condamine floodplain crossing design. The proposed design remains within the existing rail corridor, and includes:
- building six bridges (6.1km total bridge length)
- constructing approximately 500 culverts (900mm – 2.1m in diameter)
- extending the proposed bridge over the North Branch by approximately 250m north
- moving the proposed Yandilla rail bridge further south and combining with the proposed Grasstree Creek bridge
- increasing the number of proposed culverts near Yandilla grain silos to ensure the drainage channel to the south of the silos has enough culverts to convey flood water
Assessment of the proposed Condamine floodplain crossing design indicates that in a 1% Annual Exceedance Probability (AEP) event, the solution is likely to change flood behaviour at 23 private properties that already experience some degree of flooding. This includes changes in peak water levels of 10-50 mm at six houses. We are continuing to work with landowners to develop mitigation measures to minimise and manage any changes to flood behaviour.
The proposed Condamine floodplain crossing design is subject to assessment as part of the Environmental Impact Statement process and may change as a result of conditions of approval, further investigations, or detailed design.
Consultation with affected landowners is ongoing.
Environment planning and approvals
The Environmental Impact Statement (EIS) is a tool the government uses to assess the project environment and evaluate any potential environmental, economic and social impacts and examine our proposals to avoid, minimise, mitigate and/or offset those potential impacts.
The project’s draft EIS was submitted to the Queensland Office of the Coordinator-General (OCG) for review in late 2019.
The draft EIS is expected to be available for public comment in late 2020, subject to feedback from the OCG.
November 4, 2020
Made in the shade with Southbrook Central State School
We’re proud to give back to our communities that are home to Inland Rail. Last month we helped Southbrook Central State School plant for the future with an Inland Rail Community Sponsorships and Donations program grant.
November 4, 2020
Sign up for a business capability workshop
The Inland Rail Skills Academy is ensuring local businesses are provided with opportunities to build capability and supply chain readiness to meet the requirements of major projects.
November 4, 2020
November 2020 project update for Border to Gowrie
Last month on the Border to Gowrie project we continued to meet with community members at our Yelarbon and Pittsworth drop-in sessions, launched a new project procurement and packaging plan, and helped Southbrook Central State School plant trees for the future.