KEILOR Downs neighbours John Tanner and John Condello want to know why their driveways — which run parallel — are sinking and how they can get the problem fixed.
The neighbours, who live on the corner of Tarella Drive and Woona Place, say the sinking driveway is damaging their cars, as the back ends tend to hit the footpath that runs in front of their properties.
The problems have been apparent for about three months, particularly after Mr Tanner’s wife tripped over the concrete while opening the gate.
Mr Condello said his family noticed the issue when the family bought a second car.
“It (concrete) hits all the exhaust pipes,” Mr Condello said.
Mr Tanner said he contacted Brimbank City Council looking for answers but was told the problem was more than likely a sewerage problem.
After contacting City West Water — the company who has two manholes in front of the Keilor Downs neighbours’ driveways — two months ago, Mr Tanner received a letter on 14 November saying the manholes passed an inspection in August.
A letter from Brimbank City Council’s engineering services manager Adrian Ashford on 25 October to Mr Tanner stated council had contacted City West Water after council staff had investigated the matter and found no council infrastructure could cause the driveways to sink. It was stated in the letter that a road opening permit would need to be obtained before the start of any works that may be needed in the road reserve (nature strip).
Another cause of the movement in the driveway could also be related to the expansive clay soil prevalent in the western suburbs of Melbourne, according to Mr Ashford.
Deakin University geology expert Dr Mark Warne said the sinking driveway issue could have been caused by a number of factors.
He said firstly, the clay under the driveway could cause the problem as the clay shrinks when it is dry and expands when it is wet.
Dr Warne said an underground leaking pipe, which in effect had caused a land cavity, could also cause it.
“It’s (leaking water or sewerage) slowly going to erode the soil,” he said.
Dr Warne said tree roots could also cause a driveway to shift. However, it was more likely the driveway would rise.
He said the only way to be certain was to have a geotechnical company to test the soil to see if there was clay or moisture.
Dr Warne said in the past two to three years, the drought had had a huge impact on soil in Melbourne, with houses that were built in the 1950s now experiencing cracking for the first time.
