We regularly monitor blue-green algae and E. coli levels at lakes Legana, Illawong and Carramar. We notify residents if these exceed the recommended standards, in accordance with Victorian Government advice.
Like any urban lake, water quality is impacted by recent rain and the surrounding environment. High nutrient levels in the stormwater entering the lakes, low water flows and warm weather can combine to trigger algal blooms. Water quality deteriorates significantly after rainfall, and on average takes approximately 48 hours to recover.
Water samples are tested by an independent, accredited laboratory. Upon being notified of blue-green algae in a lake, we put up signage advising people to avoid contact with the water until we receive three consecutive negative results back from the lab. Read more about the health effects of blue-green algae.
Water quality improvements
Bore flushing at lakes Legana and Illawong
Under licencing from Southern Rural Water, we discharge on average 2ML of bore water per day to Lake Legana, up to an annual maximum of 730ML. We monitor this closely to ensure that our water entitlement is used according to our licence conditions.
Since bore water pumping was introduced, blue-green algae outbreaks in lakes Illawong and Legana have declined appreciably.
Bore flushing charge: 1 July 2024 to 30 June 2025
An annual Bore Flushing price is charged to individual Quiet Lakes properties that border Lake Legana or Lake Illawong. It was developed following a bore water flushing trial and pricing consultation with all residents.
In 2021, the Essential Services Commission approved an annual charge of $149.64 for a five-year period from 2021/22 to 2025/26. The charge is applied and itemised on your water bill from South East Water, starting 1 July 2024.
Through-flow options for Lake Carramar
Following the Essential Services Commission’s decision regarding lakes Legana and Illawong, we advised we would assess potential solutions enabling water to flow through to Lake Carramar.
Further options and cost-benefit analyses are still underway for Lake Carramar, as moving water in and out of the lake is not as effective at reducing blue-green algae compared to Legana and Illawong.
Further updates will be provided once the analysis is complete.
How you can help
There are simple actions you can take to help protect water quality in the lakes. These include:
- stopping litter, including lawn clippings, from entering the lakes and drains
- reporting blocked sewers to South East Water
- improving stormwater quality by:
- using low-phosphate detergents
- using less fertiliser
- washing your car at licensed car washes
- keeping beaches clear of garden and organic waste
- disposing of garden waste in green bins.