Maylands Lakes

In 2024, the City engaged a specialist consultant to prepare a Maylands Lakes Environmental Restoration Masterplan that will approach the water quality issues in a holistic manner.

As part of developing the Masterplan, the consultant Alluvium has been provided with all previous research and data from the City and undertaken additional analysis to better understand the water quality challenges.

This has included reviewing lake water and groundwater assessments undertaken by GHD, and others associated with the Maylands Lakes project. GHD had previously developed estimates of water balance that Alluvium has further refined by considering additional catchment runoff and nutrient concentrations.

Alluvium has also considered international literature around the rates of contributions from birds (Hahn et al 2007) and estimates of cormorant numbers from observations and those reported by community members. The Hahn paper highlighted a per capita loading rate of non-breeders of between 4.5–11.5g Nitrogen per day and 2.1–3.2g Phosphorus per day in great cormorants. Using groundwater contributions of 0.23mg/L and surface runoff contributions of 0.1 mg/L for total phosphorus, Alluvium used the water balance estimations to calculate the loads from the various water sources (groundwater, surface water and lake water), and then estimates of the bird numbers, which ranged from 30 to 300 birds, conservatively estimating 100 birds present for nine months of the year. Alluvium also investigated similar estimates for total nitrogen.

This research has shown the bird contribution is significant (up to a third), and if bird numbers were much lower, the contribution would still be a factor in the overall function of the lakes. Advice received from ecologists, water quality scientists and hydrogeologists indicate algal blooms in Perth occur whenever the water conditions are favourable and there is sufficient phosphorus to ‘feed’ the blooms. Any source of phosphorus, whether it be from groundwater, surface water, sediments or birds, is going to provide the necessary ‘food’ for algal blooms to occur.

Reducing these inputs is a primary focus of the City’s actions, therefore focusing on reducing nutrient inputs, including those from birds, will all help make conditions less favourable for future algal blooms. The City will be planting vegetation on the islands across our winter planting seasons. These works will include establishing appropriate endemic species on the islands to support a more diverse habitat, including sedges which will also act as a natural filter to remove nutrients.

The City will be applying Phoslock to Brickworks Lake as part of ongoing efforts to improve water quality within Maylands Lakes.

The current condition of the lake has been impacted by elevated phosphate levels, resulting in algal blooms. To address this, the City has chosen Phoslock, a scientifically proven and environmentally safe treatment, to bind excess phosphorus and prevent it from contributing to further algae growth. Phoslock is safe for aquatic life, plants and people, and is an effective measure to restore the ecological balance of lakes.

Works will commence on Monday 20 January 2025 and are expected to be completed within the day. Contractors will apply the treatment to the water directly, and all work will be undertaken during business hours. The water will be cloudy as a result.

If you have any questions, contact the City’s Environment Manager Alex Devine on 9272 0660.

The City is undertaking works to prune vegetation on the islands in Lake Brearley and Bungana as indicated in the aerial map below.

Contractors will prune vegetation to one metre in an effort to deter the cormorant population.

Cormorants using the island vegetation during winter are contributing to water quality challenges within the lakes.

Pruning will limit the volume of guano produced by the cormorants, therefore reducing additional nutrients entering the lake.

This action is part of the City of Bayswater’s continuing efforts to mitigate water quality issues within the Lakes.

Works will be undertaken from Monday 20 January and continue into February. Works will include the use of chainsaws and machinery and will be undertaken during business hours.

Local native species will be planted on the islands in winter 2025.

If you have any queries regarding the above, please contact the City’s Manager of Environment Alex Devine on 9272 0660.

On Thursday 12 December, the City held its third Maylands Lakes Community Forum at the Maylands Sport and Recreation Club.

The workshop report and slides can be found below and in the Documents section to the right-hand side of this page.

• Workshop Report
• Slides

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On Thursday 14 November, the City held a Community Listening Post for residents to share their experiences of the lakes. Facilitated by Tony Weber from Alluvium Consulting and Paul Verity and D'Arcy Hodgkinson from Josh Byrne and Associates, input from the event will help inform development of the Maylands Lakes Masterplan.

Thank you to those who attended. If you were unable to make it, your input is still invited via the City's Maylands Lakes Masterplan webpage until 5pm, Wednesday 4 December.

A reminder the next Maylands Lakes Community Forum will be held in December as part of the City’s commitment to addressing the water quality and midge issues at Maylands Lakes. This will be the third forum.

Maylands Lakes Community Forum

Date: Thursday 12 December 2024

Time: 5.30pm (for a 6pm start) – 7.30pm

Location: Main Function Hall, Maylands Sport and Recreation Club, 50 Clarkson Road

RSVP: By 5pm, Friday 6 December 2024 to Coordinator Executive Services, Nicole Ceric, via nicole.ceric@bayswater.wa.gov.au or 9272 0622

The City will be installing permanent fencing around the Peninsula Estate playground this month for improved safety.

From Monday 11 November, the City will be trialling a new water additive in Brickworks Lake aiming to reduce algal blooms.

The City will monitor outcomes of the trial over the next three months.

Over the past month, rainfall and warmer temperatures have provided optimal conditions for midge breeding within Maylands Lakes.

In October, a larger larvicide treatment was undertaken for midge within Lake Brearley, in accordance with the City’s Australian Pesticides and Veterinary Medicines Authority (APVMA) permit. While monitoring has revealed midge numbers are reducing, it is expected there may be some fluctuation over the coming weeks as a result of further rainfall.

The City will continue to undertake treatments and raking on a 14-day rotation with another larger treatment scheduled for December.

Four additional midge traps have also been deployed around the lakes this week, bringing the total to 20 traps.

The City continues to actively work on reducing midge numbers through the application of larvicides to the maximum permitted levels within the lakes and the raking of midge breeding areas.

The City is installing two water tanks around Brickworks Lake reserve to irrigate surrounding areas.

The City has turned off the pump that previously extracted irrigation water from the lake as a precaution due to the presence of cyanobacteria.

A temporary tank will be operational later this month, with a permanent tank to be constructed next to existing bore infrastructure. The permanent tank will be operational from late January 2025 and the temporary tank then removed. Both tanks will allow irrigation to be supplied directly from the bore without connection to Brickworks Lake, eliminating any risk associated with cyanobacteria.

The City will manually water the reserve in the coming weeks using water trucks until the temporary tank is operational. Any yellowing of turf is expected to recover when the temporary tank is in operation.

The temporary tank location (November to January) is shown in blue, with the permanent tank location shown in orange.

Temporary pipework will be visible for connecting the temporary tank to existing irrigation infrastructure. Vehicles will be required to access the reserve during construction of the tanks, with appropriate traffic management in place.

Two trees will be removed to make way for the permanent tank. These trees have been assessed by an arborist as poor quality and will be replaced with 10 Marri trees (Corymbia calophylla) in the 2025 winter planting season. Marri trees have been chosen due to their suitability as a foraging plant for Carnaby's black cockatoo.