Project Updates

Stay up to date on the review of Freshwater Lake.

Project background

We are reviewing the way Freshwater Lake (also known as the Delfin Island duck ponds) on Delfin Island at West Lakes operates and exists. Freshwater Lake is located within Freshwater Lake Reserve.

Freshwater Lake was constructed in the 1970s as a key water feature of the West Lakes Delfin Island Development. It was built to the standards of that era and now requires a high level of ongoing maintenance due to its unique design, structure and age.

Given the high level of ongoing maintenance needed and the resources this requires, we are doing work to review how we are managing this site now and into the future. This includes the identification of short and long-term costs and potential maintenance planning requirements.

Freshwater Lake - much loved by our community

In March 2022 we asked our community what they love, or would like to change, about Freshwater Lake. Feedback received through this first stage of the Community Engagement has identified a strong community preference for the retention of Freshwater Lake.

Of the 632 residents who submitted a feedback form, 96% wish to keep Freshwater Lake in its current form.

Feedback has identified that any option to change or reduce the size of the lake or eliminate the water body completely was not supported by our community.

Read our one page summary of the community sentiment gathered during the first stage of community engagement.

Focus on options that keep Freshwater Lake

Given the strong community support for Freshwater Lake, Council responded and refined the scope of the review to the two options that retain the lake in its current form. Other options have been removed from the scope.

This option proposes to continue to operate Freshwater Lake as we currently do. This option requires the lake to be drained and de-sludged (de-watered and cleaned). The desludging operation is conservatively estimated to cost around $600,000 . This desludging operation is an ongoing requirement of lake management (approximately every 10 years).

De-sludging is necessary to remove the build-up of nutrient containing sediments and improve the overall water quality of the lake. As sludge builds up over time, it reduces the amount of water above this sludge layer, making the water body above more shallow and more prone to warming and greening.

Desludging alone will not provide a permanent improvement to water quality. It will provide a limited improvement for approximately 5-10 years, depending on the prevailing conditions.

This option does not address lake seepage (leaking), water circulation issues, high evaporation, treating the bottom of the lake to make future de-sludging easier and more effective, or reviewing the source of water for filling the lake (currently drawn from groundwater).

This option proposes to continue to operate Freshwater Lake as we currently do but with improvements to permanently enhance lake performance and quality, operations and management. This option requires the lake to be drained and de-sludged. The desludging operation is conservatively estimated to cost around $600,000. This desludging operation is an ongoing requirement of lake management and with improvements to lake performance and quality, operation and management, this may occur less frequently than every 10 years.

De-sludging is necessary to remove the build-up of nutrient containing sediments and improve the overall water quality of the lake. As sludge builds up over time, it reduces the amount of water above this sludge layer, making the water body above more shallow and more prone to warming and greening.

Desludging alone will not provide a permanent improvement to water quality. It will provide a limited improvement for approximately 5-10 years, depending on the prevailing conditions.

Maintaining the lake in its current form but with improvements to permanently enhance lake performance and quality, operations and management will also need to consider:

  • Means of making long-term improvements to water quality and fix the leaks to the lake.
  • Treating the bottom of the lake to make future de-sludging easier and more effective.
  • Addressing poor water circulation.
  • Reviewing the source of water for filling the lake (currently drawn from groundwater).
  • Managing aquatic plant and animal life, including controlling carp.

Recent action and next steps

We have now considered engineering options and community sentiment, and we are preparing for the next stage of engagement which will start in late July 2022.

We understand that Freshwater Lake and Reserve is incredibly important to our community. We want to reassure our community of our commitment to be open and transparent in this process. We want our community to be fully informed of the options being explored, and we encourage everyone to have a say.

We will continue to inform and update our community at key points in the process.

Project background and previous community engagement

To read more about the background of this project and community sentiment gathered during the first stage of engagement, refer:

  • the section on this page titled "More information"; and
  • the section on this page titled "Document library".