Council Watch

Watching Central Coast Council on behalf of fair-minded and reasonable people.

Central Coast Council Watch

Community needs to live with flooding

by

Flooding in Tuggerah Lakes can not be eliminated, says report

Council has announced that the Tuggerah Lakes Entrance Management Study has been completed and is on the council website.
The study was prepared by the NSW Government’s specialist advisor, Manly Hydraulics Laboratory (MHL) and included an Interim Entrance Management Procedure.
The aim of the study was to develop an evidence-based Interim procedure to reduce the risk to life, public and private infrastructure and public health.
The Study’s executive summary says: “It is important to note that flooding in Tuggerah Lakes cannot be eliminated.”
“The impacts of flooding will continue to be experienced even under the implementation of the proposed interim management procedure and will likely worsen with sea level rise.
“It is important that the community in the Tuggerah Lakes Floodplain understand their level of flood risk as well as adapt and prepare to live with the impacts of flooding.
“Reviewing and updating planning controls will be vital for future flood risk management in Tuggerah Lakes given the significant low-lying development situated in the Tuggerah Lakes foreshores,” the executive summary said.
The management study was commissioned in July 2020 and was finalised this month.
The report’s conclusion states that the interim procedure does not seek to maintain a permanently open entrance and the entrance channel will naturally constrict with sand, particularly during dryer periods with low rainfall and scour to a wider entrance during wetter periods with increased rainfall.

“The interim procedure seeks to allow natural entrance processes to operate with minimal disturbances in accordance with the Policy and guidelines for fish habitat conservation and management.

“Entrance works are to be undertaken immediately prior to flooding to assist in providing flood risk reduction.

“Regular ongoing entrance berm works to continuously maintain flood-ready berm conditions were not considered to be feasible given the highly dynamic nature of the entrance including berm rebuilding and channel infilling processes.

“The interim entrance management procedure is to be reviewed following flood events as required,” the conclusion stated.

The Interim Entrance Management Procedure was used to manage the channel during this year’s flood events, Council said.

“This procedure is supported by flood intelligence tools that provide real-time predictive lake level modelling and data to ensure a proactive and informed response from Council when flood events are predicted,” Council said.

“This Interim Procedure will be included in the SES’s Central Coast Local Flood Plan, which provides guidance on flood response.

“The Interim Procedure is intended to guide Council’s channel management until an Entrance Management Strategy can be completed through the Tuggerah Lakes Coastal Management Program.

“Community input will be sought as part of upcoming consultation on the Coastal Management Program, which is currently in development.”

Council met with the SES, police and State Members last week to discuss flood mitigation and preparedness.

Council told the meeting t had received funding from the NSW Government to review and update the 2014 Tuggerah Lakes Flood Study which will inform an updated Floodplain Risk Management Study and Plan.

“This project is now underway and will allow for an updated understanding of flood risk and behaviour within the Tuggerah Lakes floodplain in order to better identify and mitigate flood risk,” Council said.

“The updated study will be able to take into account intensified development within the catchment since the last study.

“It will not only update anticipated flood frequencies and heights, but also identify flood velocities within the floodplain to better understand current flood risks.”

See the report on the Council website: search for Tuggerah Lakes Entrance Management Study.