Perry Lakes Replenishment Project Makes a Splash

Published on 06 February 2023

The Town of Cambridge has launched its $3 million Perry Lakes Replenishment Project, enhancing the amenity for nearby residents and visitors to Perry Lakes while also preserving natural groundwater resources through the redirection of fresh stormwater in a bid to restore historic water levels.

Mayor Keri Shannon, Elected Members and Acting CEO Kelton Hincks gathered with former Environmental Protection Authority CEO Barry Carbon, University of Western Australia Hydrogeologist Adjunct Professor Don McFarlane and representatives from civil construction company Civcon and Newman College today to celebrate the project launch and turn on the scheme, allowing water to flow from the Herdsman Main Drain into Perry Lakes.

The Town of Cambridge (the Town) has been grappling with increasing pressure on its water resources, including declining groundwater levels, for a number of years. The Town has undertaken managed aquifer activities at Perry Lakes to recover fresh stormwater that is otherwise discharged to the ocean through the Herdsman Main Drain and redirect the precious stormwater resources to recharge groundwater levels and replenish the Lakes.

With an average 27 megalitres of water per day being lost to the ocean through the Herdsman Main Drain, the Town’s project works will allow an average 4.7 megalitres per day to be diverted to Perry Lakes. In the course of a year, this equates to nearly 4,000 Olympic-sized swimming pools of stormwater being lost, with the Replenishment scheme able to redirect just over 680 Olympic-sized swimming pools to the Lakes. The redirection of fresh stormwater mimics natural processes, supporting the maintenance and seasonally occurring fluctuations of water levels at the Lakes through the year. It is expected that a prolonged impact on water levels as a result of the project will be measurable from spring this year.

The scheme was developed in consideration of the Department of Water’s managed aquifer recharge recommendations. Through more efficient management of groundwater levels at Perry Lakes, the Town will be able to draw on and redirect water supplies from sources that may be otherwise wasted, improving water availability, and eliminating the need for bore water pumping to the east lake. The project provides environmental, social, and economic benefits for the local and wider Perth community, improving the availability of limited but valuable freshwater resources.

In addition, the scheme will restore and sustain this incredible natural area, which is highly valued by the community and visitors. The Town recognises the uniqueness of our local environment and remains committed to ensuring the longevity of our biodiverse landscape for future generations.

The project has included the installation of more than 85,000 wetland plants which have been planted as part of a State Government Grant to aid in the improvement to water quality. The lakes act as a source of drought refuge for local wildlife in the area, and it is hoped that as a result of these efforts to restore historic water levels and reinstate native vegetation, the project will stabilise lake banks, improve water quality, and provide an improved feeding habitat for birds, frogs, and invertebrates.

The Town committed $3 million in capital works funding to this important project and received $300,000 in grant funding from the State Government for revegetation works at the parkland.

Town of Cambridge Mayor Keri Shannon said:

“For over 10 years the Council had considered various ways to replenish the Lakes. In November 2017, as Mayor, I was contacted by Mr Barry Carbon, former CEO of the Environmental Protection Authority, who recommended this solution and assisted the Town with professional advice to deliver it. The Town is indebted to Mr Carbon. The Council has been proud to lead the replenishment project at Perry Lakes using this solution and water source.”

With pressure on finite water resources steadily increasing, it becomes more important than ever for local governments to implement innovative water management approaches to improve and sustain supply.

The works undertaken not only conserve water resources otherwise lost to the ocean, but also support the recharge of groundwater levels in the aquifer. This more efficient management of resources improves limited water supply elsewhere in the community.

This project will create real and lasting change for the Town and is demonstrative of this Council’s commitment to championing sustainability and conservation for our locality.”

Acting CEO Kelton Hincks said:

“The Perry Lakes Water Replenishment Scheme was a unique project that presented many challenges for our project team. These were overcome through working closely with our key stakeholders who assisted in making this project a success.

This new scheme will automatically divert stormwater to Perry Lakes that would otherwise be wasted resulting in both positive benefits to the environmental and community.”