The coastline around Lake Cathie is particularly exposed to coastal processes that threaten private and public assets. Coastal erosion has occurred south of the Lake Cathie entrance and has led to exposure of coffee rock that underlie the dune system. Coffee rock is formed by the process of induration - which is the hardening of soft sand. This coastal erosion is likely to increase over time under current predictions for climate change and the projected sea level rise. Lake Cathie has been identified as one of fifteen (15) coastal erosion “Hotspots” along the NSW coast by the Office of Environment & Heritage (OEH)
The Coastal Zone Management Plan (CZMP) process for Lake Cathie3MB pdf(PDF, 3MB) came about after the following studies were undertaken.
- The Lake Cathie Coastal Hazard Study - completed in 2008 and later revised in 2010 to take into account the introduction of the NSW Government’s sea level rise planning benchmarks (NSW Sea Level Rise Policy, 2009).
- The Lake Cathie Coastline Management Study - Stage 1 - completed in 2009 provides a preliminary assessment of 13 potential options to address coastal hazards for this area.
- The Lake Cathie Coastline Management Study - Stage 2 - completed in 2012. This report identified the need for Council to address Coastal Management options and the following 4 options were assessed in more detail and included in community consultations.
- 400m Revetment protection for Illaroo Road
- Beach Nourishment
- Planned retreat including acquisition/voluntary purchase
Community consultation concluded with an overwhelming support for a revetment wall with beach nourishment.
(Lake Cathie / Lake Innes Coastal Model Development and Investigation)
The Lake Cathie CZMP incorporates a revetment and beach nourishment as the management option in particular for Illaroo Road and will guide the management of the Lake Cathie foreshore into the future to ensure the most beneficial outcome for local residents, the community and the environment.
Under Section 55G of the Coastal Protection Act 1979 the CZMP requires certification from the minister. In a letter dated March 2015 the Minister for the Environment requested a number of actions be undertaken before the CZMP would be certified.
a) Updated costs of the revetment wall.
b) A Cost Benefit Analysis (CBA) be undertaken.
c) Consider reviewing the management of stormwater to minimise the direct outflow of stormwater onto the beach.
Council completed these actions and additional information has been incorporated into the Lake Cathie CZMP including the results of a social and economic assessment of coastal protection options, which supports Council’s preferred option of a revetment as the main long-term management option in the CZMP.
The revised CZMP was adopted by Council in April 2016 and was certified by the Minister for Planning on 1st November 2016. The CZMP was published in the NSW Government Gazette on 27th January 2017.
The finalisation of the certification came with a further list of required actions to implement. The key actions items being a Funding Model to develop a workable funding model based on a distributional analysis that accords with the provisions of the new NSW Government Coastal Management Manual.
As of February 8th 2021, Council is engaging with the property owners that would be directly benefitting if a revetment wall occurs, along with the surrounding Lake Cathie community, to discuss the findings of the CBA and the Funding Model. This engagement will determine if the property owners directly, and indirectly, benefitting from the construction of a revetment wall have the capacity or willingness to fund the revetment wall that will mitigate the coastal erosion issue.
For more information about Illaroo Revetment Wall with Beach Nourishment project download the informational brochure.
Illaroo Rd Revetment Wall Information Brochure913KB pdf(PDF, 913KB)
This page was last updated on: 09 February 2021