Managing coastal hazards through beneficial reuse of dredged sand and an adaptive work strategy

Royal HaskoningDHV was appointed by Shoalhaven City Council to develop a strategy to deal with increased demand from the community for improving navigation and boating safety at a number of estuarine locations within the Shoalhaven Local Government area. 

This strategy was documented in the Shoalhaven City Wide Dredging Feasibility Study that was prepared in consultation with nominated community members of Council’s Natural Resources and Floodplain Management Committees.  Dredging proposals at Currambene Creek, Sussex Inlet and Lake Conjola each received funding from the NSW State Government through the Rescue our Waterways Program.

The three separate dredging projects all involve the removal of clean sand suitable to be beneficially reused as foreshore and beach nourishment. Four beach and foreshore areas were considered feasible for nourishment activities to assist with managing coastal hazards, two of which are “authorised location” beaches; namely at Mollymook, and Callala Beach.

Council had previously developed conceptual designs for “end-state” protection of property at its “authorised location” beaches however, these are costly to implement and are presently unaffordable.  Therefore, an adaptive works strategy was developed for moving from “make-safe/make-good” to “endstate” protection.  Due to suitable sand becoming available as a result of the dredging works, components of adaptive works strategy are being implemented.

The approach of beneficially reusing dredged sand for area in need of nourishment and development of the adaptive works strategy is providing opportunities for Council to manage coastal hazards in a more timely and cost effective manner.

CONTACT US

Gary Blumberg

Sydney, AU

gary.blumberg@rhdhv.com