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Tuesday, 21 September 2021

Seen equipment moving into Narrabeen lagoon? Every 3-4 years we do a major excavation of sand from the entrance of the lagoon to help reduce flood risk and increase tidal flow. The excavator is moving in to start this work today.

Repairs to the abutments of Ocean Street Bridge will be done simultaneously to minimise disruption to the community.

The works will take about 12 weeks to complete (weather dependent) with the entrance reopened in time for the summer holidays.  These works are generally timed to avoid the disruption from the winter storm season but to reopen in time for the peak swimming season.

There may be minor traffic disruption and some limits to access to parts of the lagoon entrance during the project.

These major sand clearances are conducted periodically as swell and tides gradually push more and more sand into the lagoon. Council completed the last Narrabeen Lagoon entrance clearance in 2018 and has had to undertake more frequent mechanical openings in recent months as the sand has built up.

Works will be conducted using amphibious excavators to pump the excess sand through flexible pipes to a central stockpile location next to Birdwood carpark. From there it will be trucked down to Mactier Street where a bulldozer will spread it along Collaroy-Narrabeen beach.

Once the major excavation is complete, the lagoon is expected to remain open for a number of years, although as always, we are at the mercy of mother nature as to how long.

To understand how Council manages the lagoon please please watch the video explainer.