Increased flooding in West Tamar’s stormwater system has prompted additional upgrades, says the West Tamar Council’s manager of infrastructure, Ian Howard.
Subscribe now for unlimited access.
$0/
(min cost $0)
or signup to continue reading
Mr Howard said roughly $300,000 in funding could be relocated from road works to stormwater upgrades, in addition to the council’s 2016/17 capital works program, after it is taken to the next council meeting.
“We’re getting much heavier rain events, we’re getting much shorter, sharper storms which cause flash flooding, and we’ve noticed this over the past three years,” he said.
“Especially this year, areas that have never flooded before have experienced flash flooding.”
In its September meeting, the council finalised tendering for stage two of upgrading the stormwater systems in Pitt Avenue, Gray St and Manning St, which was identified as deficient.
Upgrades will also be conducted in Ocean View Drive, Greens Beach.
Mr Howard said the council generally addressed the urban areas first as they were most at risk of damage.
He said about a year-and-a-half ago the council begun a program analysing stormwater catchments in the municipality, using hydraulic modelling and field work to investigate pipe sizes.
Mr Howard said analysis had so far been conducted in Trevallyn and Riverside, with plans to continue in Legana.
“What this is showing is there are areas, especially some of the older areas, where pipe sizes are not adequate.
“Quite often because of development that’s taken place over the last 20 years and some of the pipes are quite old.”
He said the hydraulic modelling analysed areas with properties at risk of flooding.
“The accepted design frequency in Australia in a residential area is to design your system so it will handle a one in 10 year storm...and see what size pipes you need.”
A report by the Antarctic Climate and Ecosystems Cooperative Research Centre showed the average rainfall in West Tamar was projected to increase from 2010 to 2039 both in the summer and winter.
