Transport for NSW
In September 2016, the West Wyalong to Forbes section of the Newell Highway corridor experienced a 43-day closure due to heavy rain and flooding of Bland Creek and within the wider Lachlan Catchment. About 20km of the Newell Highway flooded between West Wyalong and Forbes in 2016.
The Bland Creek system at Marsden between West Wyalong and Forbes is a series of causeways and is usually the first part of the Newell Highway cut during large widespread events. The Bland Creek system flows into the Lachlan River System. In total flood water crossed the Newell Highway at seventeen locations between Compton Road, West Wyalong and Hereford Street, Forbes. The length of these flooded sections varied from 0.16km to 4.5km, while the depth of the flood crossings varied from 100mm to 800mm depending on the topography.
In March 2019, the Coalition Government announced it would spend $200 million flood proofing the Newell Highway between Forbes and West Wyalong.
The objectives of the project were to design options to achieve a trafficable road network between West Wyalong to Forbes that achieved a minimum flood passable level of service for an equivalent 2016 flood event; a minimum flood immunity of 1 in 20 ARI; and assess and value manage options for flood immunity passable for up to a 1 in 50 flood event.
Bellwether functioned as the constructability advisor and workshop facilitator.
Our team facilitated the Health and Safety in Design (HSiD) Workshop and the Risk Management Workshops.
We provided certainty on the constructability of this project though our reviews of the program & methodologies and our risk inputs during HSiD phases.