Beloved natural asset Lake Illawarra was back on the agenda for both Wollongong City Council and Shellharbour City Council this week as the councils work to manage erosion in the entrance channel.
Acting under the Lake Illawarra Coastal Management Program, which is funded and endorsed by the NSW Government, the councils have just completed an Entrance Options Study. The study considered a range of ways to manage erosion which has occurred since the lake was manually opened in 2007 by the former Lake Illawarra Authority.
Watch: Changes to the entrance channel from 2004 through to 2024.
The two-stage study was undertaken by experts from the University of NSW Water Research Laboratory alongside experienced coastal staff.
Stage 1 reviewed historical data and literature of Lake Illawarra and other similar systems. More than 50 management options were initially considered and reviewed to narrow down a shortlist of 5.
In Stage 2, the shortlisted options were further assessed to determine their impact on water quality, recreational safety, flooding, cultural heritage, coastal storms, fishing, flora and fauna, and boating access. The community was asked what they thought of the options and, with a trade-off required, which values of Lake Illawarra they would most like protected.
Lord Mayor of Wollongong Councillor Tania Brown praised the 550 residents, stakeholders, and representatives from the local Aboriginal community who got involved to help find the option that best balanced benefits with potential impacts.
"The local knowledge and lived experience shared was invaluable. Responses showed a clear passion for preserving and protecting Lake Illawarra and all that it offers," said Cr Brown.
"We have said all along there is no silver bullet to resolve the complex erosion issues. Anything we do to stop or slow the current will reduce flushing of the lake and therefore aspects of water quality, a value key to residents."
"Lots of respondents also appreciated the complexity of the issue and asked that we be measured in how we manage it."
"However, with even the 'cheapest' option, estimated to start at tens of millions of dollars, we councils can't do this alone. With the completed study under our belt, we now know what we can do ourselves and what we will need help to deliver."
Both councils this week resolved to call on the NSW Government to "resource and undertake a Strategic Business Case to deliver a long-term management solution" considering "Option 4 and Option 5 or variations thereof" from the Lake Illawarra Entrance Channel: Management Options Assessment report.
Cr Brown explained that Option 4 would see low-lying rock barriers installed into the channel at an estimated cost of between $145 and $240 million. Option 5 would involve works to return the lake to its natural state of opening and closing intermittently ($35-$70 million).
Shellharbour City Mayor Chris Homer echoed Cr Brown's comments that these resolutions were the next step in a process needed to protect the lake.
"I love the lake. I swim there frequently and we want the best outcome. If bringing the State Government in is the best solution, then I'm all for it," said Mayor Homer.
"There is still a lot of work that needs to be done, we have already had lots of expert advice and community input. We will continue to work together with Wollongong Council and State Government departments."
