Northern Beaches Council is about to begin the task of clearing the entrance of Narrabeen Lagoon.
During the works, around 50,000 cubic meters of sand will be shifted and used to replenish Collaroy–Narrabeen Beach which suffered devastating erosion in the June East Coast low.
While the overall size of the lagoon is large the entrance is only approximately 30 meters wide and due to wave, current and wind processes, marine sand slowly closes this entrance approximately every three to five years.
“The sand that finds its way to Lagoon entrance is part of the same beach system that includes Collaroy–Narrabeen Beach and it is important that the sand is returned there to ensure ongoing replenishment of the area,” said Northern Beaches General Manager, Mark Ferguson.
As well as assisting with the replenishment of the beachfront, the removal of the sand from the lagoon entrance increases tidal flushing, improving both biodiversity and water quality and helps reduce some low-lying flooding.
These major entrance clearance works are undertaken in late winter to minimize storm and recreational impacts. Approximately 100 truckloads of sand per day will be removed from the eastern and western sides of the Ocean Street Bridge between July and October 2016.
This will be the 9th major clearance project at the entrance since 1975, with the most recent being in 2011.