Lower Yarra River Dredge Study

Background

Client: Parks Victoria

Commercial and recreational boating in the lower Yarra River is constrained by siltation of navigational channels. Dredging operations to remove the siltation material are also challenged by restricted access and few dredge material management options.

Assessment of a proposed dredging and material management strategy included 3-dimensional (3D) hydrodynamic and sediment transport modelling of the lower Yarra River, a stratified ‘salt-wedge’ estuarine system. The modelling represented the density gradients through the water column and the influence this has on the advection-dispersion of dredge plumes and resuspension of the bed sediments. The assessments demonstrated that lower Yarra River water quality objectives could be met during the proposal operations. 

Outcomes and Benefits

This project assisted Parks Victoria with a potential strategy to address siltation issues in the lower Yarra River. The outcomes may be used to support an approvals application to undertake the proposed works.

Services and Expertise Provided:

• Bathymetric survey analysis;
• Dredging and material placement design;
• Sediment quality data analysis;
• 3D hydrodynamic and sediment transport modelling using TUFLOW FV;
• Environmental risk assessment (water quality); and
• Recommendations for further sediment sampling and analysis to meet requirements of national dredging guidelines.