Seashore Engineering was commissioned by the City of Bunbury, with the support of Bunbury Port Authority and the Department of Transport, to investigate erosion occurring at Koombana Beach, Bunbury and determine an appropriate coastal management strategy that achieves optimal outcomes for both the short and long term.
Concept designs for eight preliminary coastal management strategies to address the existing and ongoing erosion threat to coastal infrastructure were developed based on a detailed level of understanding of coastal processes at Koombana Beach developed through desktop review and survey analysis. Each strategy was reviewed in conjunction with the City of Bunbury and Bunbury Port Authority based on engineering performance and financial sustainability to select two preferred strategies for a more detailed evaluation. The two selected were;
- Renourishment using sand from the Outer Harbour sand traps and a revetment along the Bunbury Port Lease Area;
- Groynes with renourishment and a revetment along the Bunbury Port Lease Area.
Detailed evaluation consisted of a design of appropriate layout and cross-sections, capital and maintenance cost estimates, recommended beach monitoring and identification of potential adaptation pathways. The renourishment strategy was concluded to provide low initial cost, a greater degree of flexibility and lower impacts to amenity and access along Koombana Beach and its implementation was subsequently recommended.