Speed Up of $3.7 M Perth Flood Prevention Plan to Protect Homes

Posted on August 15, 2023

Northern Midlands Council aims to bring forward work to speed up completion of a $3.7 million project to protect homes around Perth from extreme event flooding.

Northern Midlands Council Mayor Mary Knowles said Council started planning the works in 2016 following receipt of a report that assessed the risk of flooding from Sheepwash Creek.

The Sheepwash Creek catchment is about 954 hectares in overall size. A 613-hectare upper area of the catchment passes through Mackinnon’s Dam, which lies to the north of Perth. Overflows from this dam pass to the creek line which makes its way through the west Perth urban area.

Mayor Knowles said the work was vitally important to protect residents and their properties.

“There are currently multiple undersized crossings of the creek which increases risk to residential properties. Flood issues are exacerbated by the topography in the urban area, which is very flat in comparison to the upper catchment,” she said.

“Climate change is very real and all levels of governments have a responsibility to plan and take action now to mitigate against future flood and storm damage,” Mayor Knowles said.

She said Council had successfully sought funding under the Commonwealth Government’s Disaster Ready Fund (DRF) to enable three road and one rail culverts to be designed and constructed on a 50-50 funding basis. The Commonwealth will also reimburse 50 per cent of the cost of works and land acquisition undertaken since 1 July 2019 to progress the overall flood mitigation strategy.

“In the grant application we proposed to stage the project over the 2023/24, 2024/25, and 2025/26 financial years. However, we are now keen to condense the project into a 2-year timeframe and are currently preparing a Project Implementation Plan with a new target completion date of 30 June 2025,” Mayor Knowles said.

“Action taken to date includes the acquisition of 35,550 square metres of private flood-prone land of which 28,932 square metres, or 81 per cent, has been designated as open space to create a natural flood plain, creek widening, improving culverts and installing swales to take water away from homes,” Mayor Knowles said.

The remaining 19 per cent of that total area was subdivided into nine residential blocks for sale to partially offset Council costs of the stormwater improvements.

“After completion of these improvements there remains 60 properties likely to be affected to varying degrees by flooding exceeding normal annual levels due to climate change. When completed, the remaining works will protect most private property from flooding in an extreme event,” Mayor Knowles said.

Mayor Knowles said an important side benefit of project was the creation of a public green space for residents.

“Eventually Council plans to build walking tracks and other facilities through this open area for the community to enjoy,” she said.

It is expected the work will also vastly improve the local environment by helping to reduce siltation further down the South Esk River catchment.

Improvements planned under the Sheepwash Creek Flood Mitigation Strategy include:

• Installation of a weir and gauge above Phillip Street, for improved calibration of the flood model (completed).
• Land acquisition and creek widening between Phillip Street and Edward Street (completed).
• Land acquisition and creek widening between the rail line and Drummond Street (completed).
• Removal of the redundant Cemetery Road culvert and trees immediately upstream of Drummond Street (completed).
• Phillip Street culvert upgrades.
• Edward Street culvert upgrades
• Abandonment of the Youl Road culvert/crossing, to be undertaken when Youl Road is handed over to NMC by the Department of State Growth.
• Installation of a new culvert under the Western Rail Line, inclusive of a pedestrian underpass, to realign the creek to a more natural alignment. (Currently the creek runs alongside Youl Road before passing under the existing road and rail culverts which are at right angles to the direction of flow).
• Drummond Street culvert upgrades (design in progress).

The Disaster Ready Fund is a $200 million Australian Government initiative to fund medium to long-term projects in partnership with state, territory and local governments to build resilience and reduce risks of disasters caused by climate change and other natural hazards.

For further information, please contact Mayor Mary Knowles OAM on 0408 766 625.