Project Overview
SKCE provided structural engineering design, documentation and certification for retaining structures forming part of the upgraded Gundagai Sewage Treatment Plant for Cootamundra-Gundagai Regional Council. Located within the Murrumbidgee floodplain in southern NSW, the project required a highly resilient structural solution capable of withstanding a 1-in-100-year flood event, significant hydrostatic loads and challenging foundation conditions.
SKCE engineered approximately 210 metres of retaining walls, ranging from 2.7 to 5.7 metres in height. Using a Dincel 275 mm permanent formwork system, the design provided the strength and stability required for extreme flood conditions while enabling a more efficient construction methodology.
SKCE Services Delivered
- Structural engineering design
- Structural documentation and certification
- Geotechnical review and wall system analysis
- Hydraulic loading assessment
- Retaining wall and footing design
- Flood-resilient structural design
- Construction methodology and pour sequencing review
- Site inspections and construction certification
- Technical coordination with the project team
Value to the Client
SKCE’s design addressed significant structural challenges presented by the floodplain location, including combined earth and hydrostatic pressures, groundwater, variable soil conditions, differential settlement and the potential for full submergence during major flood events.
The Dincel permanent formwork system reduced the need for conventional formwork and extensive temporary works, enabling full-height continuous pours of up to 5.7 metres with limited external bracing. This simplified site operations, reduced labour requirements and construction time, and delivered cost efficiencies compared with traditional formed concrete retaining walls.
