Toowoomba council endorses new West Creek master plan to prevent impacts of future rain events

It’s a part of the Toowoomba CBD known for creating rushing torrents and flooded streets — now the council has endorsed a $4.4m plan to help ease its impacts.

One of the Toowoomba CBD’s most notorious flood zones could see water levels reduced by up to 150mm if the council moves ahead with a $4.4m plan to upgrade West Creek.

Councillors at Tuesday’s committee meetings voted to endorse the new West Creek Masterplan stretching from James to Herries Streets in Toowoomba City.

The plan, designed by engineering consultants Engeny Australia, would see a series of weirs and baffles installed to slow the flow of water during significant rain events.

It comes after parts of the West Creek suffered degradation due to recent flooding, most notably in February 2022.

According to the report by drainage planning principal Avril Campbell, continued concrete repair works were not considered a viable long-term solution, as they would cause increased water velocities during heavy rain events.

“Under this current remediation approach, the waterway would eventually result in a fully hard lined waterway profile which would introduce destructive water velocities downstream,” she wrote.

“As this reach of West Creek is subject to high velocity flows, a fully natural solution is not practical to construct and maintain in the limited corridor available.”

West Creek, James to Herries masterplan

Engeny’s proposal would see West Creek maintain its “green spine” image while reducing the risk of flooding during 1-in-100 chance events by 150mm in some parts.

“It is proposed to construct a larger waterway profile within the limits of the existing banks, and a series of low flow weirs to retain some standing water and provide a more aesthetic appearance to the reach while ensuring stability of the underlying creek bed,” Ms Campbell’s report said.

“This would be further softened by significant embankment plantings of native vegetation to enhance the natural appearance and conceal some hard surfaces.

“Energy dissipaters will also be incorporated downstream of the weirs to aid in managing velocities.

“Hydraulic modelling of the preferred masterplan approach has indicated that water levels in the nominal 1 per cent AEP (Annual Exceedance Probability) flood event have been reduced by up to 150mm in some areas.”

The entire project has been budgeted at $4.4m in a staged delivery.

It will now be added to the council’s 10-year capital works budget, to be delivered in the future and potentially brought forward if external funding was secured.