When it comes to bodies of water such as lakes, it is not uncommon to see water quality dip from time to time, particularly during the summer months when warm water temperatures, combined with low oxygen levels and high nutrient loads lead to algae blooms and bacterial infestations. Pollutants such as chemicals from garden fertilisers and pesticides that are washed into the lake through stormwater run-off from the surrounding areas, animal droppings and other debris such leaves also contribute to a decline in water quality.
Peter Hopper Lake is a large lake and requires substantial rainfall to be able to “refresh” itself frequently. When this doesn’t occur, the water can become stagnant, adding to issues of water quality.
Council has been working to address the poor water quality we are seeing in the lake by undertaking a number of different actions, including adding binding agents to help improve the water quality (the binding agents help remove excess phosphorus in the water) and installing four air dispersers to help oxygenate the water at its deepest and most stagnant locations.
We will also continue to apply a specialised treatment which is designed to increase the oxygen levels in the water.
Unfortunately though, we are seeing that these efforts are not making a significant difference and further, more substantial work is required to improve the long-term health of the lake.
Council is currently in the design phase and we expect to install a Gross Pollutant Trap at the lake’s inlet in the new year to help prevent further contaminants such as silt and litter from entering the lake.
Rectifying water quality in a lake the size and age of Peter Hopper Lake is not a simple fix.
When the lake was constructed in the mid-70s the design standards were different to what they are today and as such, the lake does not contain the necessary functionality (such as appropriate litter screening and built-in vegetation to capture silt and absorb nutrients) to be able to effectively manage the water within the lake. This means that interventions and treatments, such as those Council have been undertaking, are required in the first instance.
However, as there are multiple factors contributing to the poor health of the lake, Council has had to consider more complex engineering solutions to ensure that the lake can continue to provide long-term benefits to the local wildlife and community.
We have been working with a team of specialist consultants over many months to thoroughly investigate the most appropriate improvements that will provide the best long-term outcomes for the lake.
The investigations have shown that more significant infrastructure is required to restore the lake to a healthy and functioning lake.
The installation of a Gross Pollutant Trap will form one part of the long-term improvement works and will assist in the reduction of further gradual contamination entering the lake. However, we know that more is required to ensure the long-term health of the lake.
Council is committed to addressing both the causes and symptoms of the lake’s poor water quality to ensure that the lake can continue to be an asset to the local community for years to come.
Council has engaged specialist consultants to investigate a range of long-term options for the lake and we will be presenting further information and seeking community feedback on this in the coming months.
As part of the long-term solution development, we will be working with the Department of Environment, Water, Land and Planning on developing a long-term, localised solution for the birds.
Visitors to the lake should:
- Avoid contact with the lake water and keep dogs on a leash. No access into the lake is permitted.
- Not handle birds or other wildlife.
- Not feed the birds as this can attract further wildlife to the site.
- Not fish in the lake.
- Don’t leave rubbish behind.
If you see any sick wildlife, please contact Wildlife Victoria on 8400 7300 or visit their website to lodge a request to have the animal attended to. Please do not handle the animal yourself.
If you see any dead animals in or near the lake, please contact Council on 9217 2170 to have the animal removed safely. Please do not handle the animal yourself.
You may be surprised to know that you can certainly make a difference to the quality of the lake by making some simple changes at home – particularly if you live within the “catchment” area of Peter Hopper Lake.
The catchment area refers to the large area of surrounding streets where water run-off – for example from rain or when you wash your car, flows into stormwater drains and then collectively ends up in the lake.
If you live in the catchment area of Peter Hopper Lake, these simple actions can make a big difference:
- Avoid using lawn fertilisers, herbicides and pesticides on your garden
- Wash your car on your lawn or at a carwash that reclaims the water
- Avoid washing anything into the stormwater network including soapy water and grass clippings
- Do not feed wild birds
You can also make a difference at the lake itself by making sure that you don’t leave any rubbish and food waste behind that could potentially end up in the water.
Getting involved in planting days or Clean Up Australia Day events is also a great way to do something that will improve your local area.