The western suburbs of Perth rely heavily on groundwater to irrigate public open space and residential gardens. Declines in Superficial aquifer water levels and quality present a risk to long-term water security and groundwater-dependent wetlands such as Lake Claremont and Perry Lakes. Potential leakage through the underlying Kings Park Formation induced by deep aquifer abstraction was considered responsible for declining groundwater levels, along with climate change and abstraction from the Superficial aquifer.
We investigated the Kings Park Formation in partnership with the Western Suburbs Regional Organisation of Councils (WESROC) and the Town of Cambridge. We aimed to better understand the evolution of the Kings Park Formation and how it impacted groundwater flow in the surrounding aquifers.
We completed the investigation in 2020 as part of our flagship State Groundwater Investigation Program.
What we did during the investigation
During the investigation we:
- drilled a total of 2,632 metres and installed 25 monitoring bores in the Superficial, Mullaloo, Leederville and Yarragadee aquifers
- collected and analysed 71 groundwater samples and 21 surface water samples
- worked with Curtin University to complete three seismic and seven Electrical Resistivity Imaging surveys
- developed a 3D geological model of the project area, mapping out the Kings Park palaeochannel under Perth
- developed new Superficial aquifer groundwater recharge estimates using a combination of land use (urban monitor remote sensing data), groundwater levels, chloride mass balance and groundwater age dating.
Key findings and how we are using the information
Key findings from the investigation included:
- Deep aquifer abstraction does not impact Superficial aquifer levels in the project area.
- The Mullaloo Sandstone aquifer could be a potential target for managed aquifer recharge in the future.
- We now have better estimates of groundwater recharge in the area, based on multiple lines of evidence and applying new methods in partnership with the CSIRO.
We will use the improved monitoring data and hydrogeological understanding to support the assessment of alternative water supplies, such as managed aquifer recharge, in the Perth’s western suburbs. The results will also inform future water allocation planning, Integrated Water Supply Scheme planning and groundwater licensing.
Where to get more details
You can ask for copies of the internal technical reports for this investigation by emailing groundwater.info@dwer.wa.gov.au. These include:
- Hydrogeological investigation of the Kings Park Formation, Perth, Western Australia: Review and scoping report, HR381 (Clohessy 2017)
- Bore completion report: Kings Park Formation groundwater investigation, HR397 (Davey et al. 2019).
Go to our Water Information Reporting portal to access data from the monitoring bores installed during the investigation.
You can access all government-commissioned airborne geophysical surveys via the Department of Mines, Industry Regulation and Safety website and download them free of charge from ‘Geophysical Surveys’ in GeoVIEW.WA or from the Geophysical Archive Data Delivery System (GADDS).
Read more about our groundwater investigations by region across Western Australia.
