Council is responsible for the management and maintenance of the lower Lake Cathie estuary (Lake Cathie Creek), the surrounding foreshore reserves and nearby beaches. Periodic dredging of the lower estuary is undertaken to ensure that recreational amenity is maintained within the waterway, with the dredge spoil being used to nourish nearby areas subject to erosion.
The lower Lake Cathie estuary is periodically dredged with the dredge spoil placed on Lighthouse Beach to create a sand buffer from coastal erosion impacts. In the intervening years after dredging occurs, sand accumulates into the lower estuary and can impact on the amenity of the recreational activities generally undertaken in the lower waterway. The sand buffer on Lighthouse Beach is typically also lost during this time due to the erosional nature of the beach environment.
This work is typically undertaken with a ‘suction/cutter’ dredge. The beach nourishment work involves placement of dredged sand in front of the properties along Illaroo road to form an artificial dune. The placement of this sand is typically undertaken by an excavator with the sand being pumped to the beach via a pipe from the dredge.
To aid in preserving the amenity of lower Cathie Creek, Council has identified periodic maintenance dredging as a suitable means to remove accumulated sand banks within the waterway. The Dredging Strategy (2007)1MB pdf(PDF, 1MB) proposes ongoing dredging every 5-10 years. The Lake Cathie Coastal Zone Management Plan (2016) identifies excess dredged sand to be placed on Lighthouse Beach to act as a mitigation measure for predicted long term coastal recession.
This page was last updated on: 30 April 2019