Greater Shepparton City Council is continuing to prioritise stormwater drainage asset management across the region, with recent extreme rainfall events putting pressure on the ageing infrastructure.
In summary:
- Council prioritizing stormwater drainage due to ageing infrastructure and extreme weather events.
- Over 450km of pipes and 60 pump stations, mostly 40-50 years old, struggle with increased rainfall intensity.
- Council working on Drainage Investigation Priority Program to address known drainage issues.
- Lenne Street in Mooroopna receiving $200,000 for investigation and design of new pump station and drainage improvements.
- Interim works aim to improve water flow while long-term solutions are developed.
There are more than 450km of stormwater pipes and over 60 pump stations across Greater Shepparton, with the majority designed and constructed 40-50 years ago. With design standards having changed since the construction of these pipes, Council is dealing with areas of the system that are under capacity and are unable to meet the increased demand.
Recent data from the Bureau of Meteorology predicts storms in Victoria are going to become more intense over the next 20-30 years with storms occurring less often, however more rainfall will occur in a shorter amount of time. Similar weather patterns have been experienced in recent months, with several extreme rainfall events hitting the region.
Council's Manager Engineering and Assets, Ben Gannon, said the region's stormwater pipe network is not designed to deal with these extreme types of weather events which are becoming more common.
"The standards for stormwater drainage have changed over recent years to cater for the extreme weather patterns we are experiencing, which means our current infrastructure is struggling. Because of this you will see more water sitting stagnant on roads and footpaths for a few hours following a storm event, before if eventually drains away," he said.
"The water will eventually recede, however it will take longer than normal as the stormwater pipes are not designed to cope with extremely large amounts of water in such a small space of time."
Council is continuing to prioritise the maintenance of its current drainage system to prepare for future predicted stormwater and riverine flooding. As part of this, Council is working on a Drainage Investigation Priority Program based on a list of known stormwater drainage issues across the municipality, prioritising factors such as flood frequency, community disruption and Occupational Health and Safety risks. Priority sites will be further investigated for new drainage design.
Such investigation works are currently underway for Lenne Street, Mooroopna, with the area regularly suffering flash flooding in stormwater events and was severely impacted during the October 2022 flood event. A total of $200,000 was allocated in the 2023/2024 Budget for investigation and design of the stormwater drainage improvements for the area, which will see detailed design plans developed for a new pump station and upgrades to existing reserves to enable them to store an additional 12,700m3 of stormwater.
Mr Gannon said these interim works would improve drainage in the area, allowing the water to flow into these catchments while it works its way through the drainage system.
"We thank residents for their understanding while investigation works have been underway to determine the next steps to improve this drainage," he said.
"While these renewal and upgrade projects are ongoing, proactive maintenance will continue to ensure the current stormwater drainage is operating at the best of its ability."