Lake Cathie

While we aren’t responsible for water quality of Lake Cathie, we do undertake water quality and algal testing for forward planning purposes. If you have concerns about the quality of the water and want to find out if it is safe to swim or fish, contact NSW Health or NSW Fisheries.

It is recommended by NSW Health that you do not swim:

• within 24 hours of heavy rain at ocean beaches
• within three days of heavy rain in estuaries or rivers

From time to time NSW Health offers general health advice for users of recreational water bodies across NSW where there is potential for contamination to cause disease and illness in the community.  If a pollution incident should occur, we will advise the community via our news channels. 

Revive Lake Cathie operate a Remote Smart Water Quality Sensor Monitor in Lake Innes that measures water quality parameters. They also monitor results as part of the Waterwatch NSW program. 

Over many years, we have been working with the community to explore a feasible option to manage the potential coastal erosion risk to private and public infrastructure at Illaroo Road. This has involved costal hazard studies, options assessments, extensive community engagement and collaboration on our forward plans.

In 2021, we engaged Rhelm and Bluecoast to carry out a co-design process to develop a reasonable, feasible and achievable solution. The findings of the report were considered at the October 2022 Ordinary Council meeting.

Council unanimously resolved to:

• Note the findings of the Illaroo Road coastal protection options review and co-design project undertaken by Rhelm and Bluecoast Consulting.
• Note that all coastal protection options identified remain available, including a high crested revetment wall, low crested revetment wall, artificial reef and groynes.
• Continue to progress short term mitigation measures for coastal erosion adjacent to Illaroo Road, including sand nourishment and stormwater protection measures and, undertake emergency works as necessary should damage to stormwater and road assets occur.
• Advise people who participated in the co-design process or made submissions to this process of Council’s determination and develop community information to keep the community informed.

We are committed to finding a sustainable long-term solution for the coastal erosion issue through the Coastal Management Plan, and to providing short term and emergency mitigation works to provide certainty that ongoing protection and access to properties will be maintained.

The results of the co-design project will be built on in the development of the Coastal Management Plan through broader community engagement.

View the final report and the associated attachments below.

• Illaroo Road coastal hazard protection options review(PDF, 2MB)
• Attachment A - data collation and review report(PDF, 7MB)
• Attachment B - options development report(PDF, 6MB)
• Attachment C - co-design workshops report(PDF, 19MB)
• Attachment D - visualisations(PDF, 3MB)

Our opening strategy guides the decision making process with respect to opening Lake Cathie to the ocean. It aims to:

• minimise adverse effects on the ecology of the area
• minimise build-up of sand in the lake entrance
• reduce impacts of flooding
• ensure residents and visitors have opportunities for recreational activities

We follow a standard operating procedure(PDF, 2MB) that outlines our required actions to manage and mitigate flood risks once Lake Cathie reaches 1.6 metres AHD (Australia Height Datum). When water levels are at 1.6m, this is not the point that water inundates sewer infrastructure or resident's home, but it is the point where we begin to closely monitor water levels.

Council monitors water levels at Lake Cathie twice daily, the frequency of monitoring increases once the 1.6m level is reached as conditions can changes quickly.

To mitigate flood risks, we scrape the high sand berm back to a level of 1.6m. The 1.6m trigger level represents the point that our staff are able to mobilise and prepare to act should these certain conditions present. It does not automatically initiate our responsibility to scrape the berm. 

At this point, we start planning and mobilising to undertake works to allow water levels to reduce before it inundates sewer infrastructure and resident’s homes. Enacting flood mitigation measures also relies on other factors, including substantial rainfall confirmed on the long-term forecast, water levels continuing to rise, and optimum tidal conditions.

Artificial openings occur on average once every 12 months and involve dredging the sand between the lake and the ocean with an excavator.

Dredging involves removing accumulated sand banks to improve the recreational capacity of the lake.  This requires permission from the state government. Excess sand is placed on local beaches to help prevent beach erosion.

You can read more about dredging in our Dredging Strategy.

The coastline around Lake Cathie is particularly exposed to coastal processes that threaten private and public property.

We have completed an extensive number of plans and studies in relation to coastal management. The Lake Cathie Coastal Zone Management Plan addresses coastal management options.

The Lake Cathie Community Plan(PDF, 9MB) is a community-led, 5-10 year plan, which was developed through a partnership between Council and the community.

The plan:

• highlights what is special and unique about the area
• reflects community’s vision for the future
• identifies key priorities and actions to achieve the community’s vision.

Heavy penalties apply for members of the public who attempt to open Lake Cathie without approval.

Port Macquarie-Hastings Council is committed to long-term planning for Lake Innes and Lake Cathie, working with NSW Government agencies while also having protocols in place to manage potential flooding and to minimise environmental impacts.

Attempting to open Lake Cathie through the lake’s entrance sand-berm is an offence under several pieces of Legislation.

Government agencies with responsibilities under this legislation will take action against persons found to be digging, scraping, excavating, dredging or moving sand in an attempt to open the lake’s entrance without authorisation, which is located on Crown land.

Maximum penalties of $110,00 for an individual or $200,000 for a corporation apply to digging up or disturbing soils on Crown Land, under the Crown Land Management Act 2016 and Regulations. Maximum penalties of $110,000 for an individual and $220,000 for a corporation apply to carrying out dredging work on water land without a permit, under the Fisheries Management Act 1994 and Regulations.

We have collated frequently asked questions about Lake Cathie, view as a PDF document(PDF, 624KB) .

We have also collated the Council's responses to Revive Lake Cathie's questions regarding dredging, mosquito monitoring, Kenwood Drive Bridge, low water levels, acid sulphate soils, marine life and fresh water sources. View the responses(PDF, 41KB) as a PDF document.