Adopted by Council
Tuesday 27 September
Narrabeen Lagoon is one of the Northern Beaches’ greatest natural and recreational assets. However, it is also prone to flooding and Council has been managing its entrance to reduce the risk of flooding for close to half a century.
We have developed a strategy which reviewed current practices and processes and established the most effective way to manage the Narrabeen Lagoon entrance moving forward.
Between 6 May 2022 and 19 June 2022, we publicly exhibited the Draft Narrabeen Lagoon Entrance Management Strategy. We received 53 submissions during the consultation period.
Thank you to everyone who provided feedback. The draft strategy and its recommendations were generally supported by the community. We also received a number of suggestions for improvement. All submissions were considered by both Council and our consultant and some amendments were made to the document in response to the feedback.
At the meeting on Tuesday 27 September 2022, Council adopted the Narrabeen Lagoon Entrance Management Strategy.
- View the Council minutes (Item 11.1, page 16)
- View the Council Report (Item 11.1, page 83) and Attachment Booklet (Item 11.1, page 126) that includes the adopted strategy document and the community engagement report.
The final adopted strategy includes a range of priority actions which we will now begin to implement including:
- trialling more frequent but smaller sand clearance operations (every two-three years rather than four-five years)
- developing a more flexible set of the conditions which trigger Council intervention to open the lagoon if required
- adjusting the alignment for the pilot channel
- reshaping and revegetating the denuded part of Birdwood Park dune to assist with sand stabilisation
- investigating the financial viability of mobile sand pumping as a longer term alternative to trucking.
Public exhibition outcomes
In 2021, we released an options paper for community input that informed the development of the more comprehensive draft strategy which was subsequently put out for community feedback in mid 2022.
Consultation feedback on the draft Narrabeen Lagoon Entrance Management Strategy indicated a strong level of support for mobile sand pumping. Feedback also indicated support for
trialling of more frequent, smaller scale entrance clearance operations and a desire for
the lagoon entrance to be open.
Mechanical opening was supported as a necessary intervention for flood mitigation purposes, however some differing views were expressed with respect to the trigger conditions for action, the pilot channel position and the management of Birdwood Park Dune.
Feedback received during the public exhibition led to some changes being made to the draft strategy, and there will be further investigation of sand pumping as an alternative to trucking.
Shaping the ongoing entrance management
As part of the development of the Draft Narrabeen Lagoon Entrance Management Strategy, we investigated all aspects of entrance management, including emergency response arrangements, clearance work improvements and long term entrance-specific options involving the installation of a more permanent structure.
During the public exhibition of the draft strategy, we invited you to read the full document, read the snapshot document or watch the explainer videos. Further below on this page, we presented the different sections of the draft strategy.
Submissions on the draft strategy closed on Sunday 19 June 2022.
Draft Strategy snapshot
Click on the lower right corner to expand the view of the snapshot document.
We created some videos to help you navigate through the information. There is one tab with a video explainer of the current Narrabeen Lagoon entrance management and another tab with a video explainer of the main options investigated in the draft strategy.
Click on the video below to learn more about Narrabeen Lagoon entrance and how Council currently manages this complex issue.
The draft strategy
Click on the video below to learn more about the main options investigated in the draft strategy for future management of the lagoon entrance.
We want to thank Greg Britton, a Technical Director with Royal HaskoningDHV, who features in the video.
Delve into the detail
Includes a summary of the initial stage of consultation conducted in Feb-Mar 2021 where we sought feedback on options to be investigated further.
2: Understanding Narrabeen Lagoon
Includes info about the lagoon environment, flood-related plans and current entrance management practices.
3: Review of Entrance Management
Includes background to ICOLL entrance management and explores state, national and international models.
4: Short term closed entrance management
Includes a review of mechanical opening practices, emergency response for flooding, options for improving practices and recommendations.
5: Medium term entrance management
Includes a review of current entrance clearance practices, options for improving practices and recommendations.
6. Long term entrance management strategy options
Includes the description, evaluation and analysis of long term management options and recommendations.
7. Implementing the strategy
Outlines the suggested prioritised implementation strategy and recommendations going forward for management of the Narrabeen Lagoon entrance.
Includes the literature list, modelling and cost benefit analysis.