Levee maintenance works to strengthen city's flood protection
Published on 05 January 2024
The City of Launceston will next week begin remedial works to top up the Invermay flood levee between the Charles St Bridge and the Victoria Bridge.
These works are expected to take approximately two months.
Since record-keeping began, there have been more than 40 significant floods in Launceston.
The Launceston levee system has been in operation since the 1960s, and has undergone a series of upgrades over the past 70 years.
Today the Launceston flood levee defence system comprises more than 12km of earth and concrete flood levees, 19 floodgates, and a series of river level gauges in Northern river catchments.
The last major upgrade was carried out between 2008 and 2012.
City of Launceston Mayor Matthew Garwood said the Invermay Flood Levee ran along the northern bank of the North Esk River, from the Charles St Bridge to Vermont Road.
"Launceston's flood levee defence system consists of a series of concrete and earth levees," Mayor Garwood said.
"Over time, the earth levees are exposed to wind, rain, erosion and subsidence and therefore require regular maintenance and topping up to ensure our flood levee defence system is functional.
"In 2017, a CRC Research report found that during the 2016 floods, Launceston's flood levee defence system prevented losses of more than $216 million to the city and region.
"However, it is important for Launceston residents to be aware that the levees are not a guarantee against flood.
"There will always be a risk of a flood event greater than what the levee system can provide protection for.
"Given the ground conditions in Invermay there is also a risk of failure. Although the Council and the Launceston Flood Authority continually inspect and maintain the levee system, the adequacy of the system can't be guaranteed in every scenario.
"That is why it's important for residents in low-lying parts of the city to familiarise themselves with flood risk, prepare an emergency kit, and make plans with friends and family for the potential relocation of pets or valuables."
City of Launceston Water Team Leader Erica Deegan said the remedial works would see the levee reinstated to its designed level of 4.85mAHD its lowest point close to the Charles St Bridge.
"The proposed remedial works involve raising the levee crest to its design level and then providing an additional top up of 300mm to the area of the levee where settlement has been greater," Ms Deegan said.
"The additional top up is to provide a settlement buffer so that as the levee settles and the underlying silts consolidate, the levee crest design level is maintained for at least five years."
Mayor Garwood said anyone living within Launceston's levee-protected areas was strongly encouraged to have their own emergency plan to enact in the event of a flood.
"We have a range of helpful resources available on our website to help residents and business owners understand their risks and develop appropriate emergency plans," he said.
Information and resources are available here: www.launceston.tas.gov.au/Emergency-ManagementHub/1.-Understand-your-risk/Flood