Memories of 1996 come flooding back
By GRAEME SINGLETON
HOW high is 20 millimetres?
It's roughly the thickness of a vegemite sandwich or the height of a stack of 10 20-cent coins.
To many Coffs Harbour residents it may also be the difference between staying dry and being flooded during the next big '1996-style' rain event in the city.
Twenty millimetres is how much higher floodwaters are expected to rise when the 'contouring option' bridge selected to cross Coffs Creek as part of the Hogbin Drive Extension is in place next year.
The issue sparked rare debate and division at Thursday night's city council meeting where the endorsement of council staff's preferred option for the bridge was a surprise late inclusion.
Councillor Rod McKelvey said he was concerned that council was being asked to approve the contouring option bridge ? a five-span 130-metre-long bridge with 200 metres of contour banks and costing approximately $5 million ? when modelling showed it would raise creek levels in the event of a one-in-100 year flood by 20 millimetres 500 metres upstream.
"We are seeing that because of
global warming flood events are
becoming worse around the world,' Cr McKelvey said.
"I can't see why we can't come up with some configuration (of a bridge) that wouldn't add to the misery of people in this city affected by flooding."
Cr Ian Hogbin was also concerned that the bridge design had not been put to community consultation along with other alternatives.
"We should be trying to avoid any backing up of water," Cr Hogbin said.
"We should know the cost of the bridge that doesn't cause water levels to rise.
"We need to make the best long-term decision for the city." The council's acting director of City Services, Geoff Newton, said he didn't believe extending the bridge by adding up to three more spans would reduce the impact of flooding. He said it would cost around $800,000 per span to make the bridge longer.
Cr Jenny Bonfield also wanted the council to do more modelling before settling on a bridge design.
"Twenty millimetres might not seem like much but there are more homes in the 1:100 flood zone now than there were in 1996, so it could result in a lot more properties being inundated by floodwaters," Cr Bonfield said.
"The 1996 storm event cost this city $300 million, so investigating a bridge design that doesn't raise creek levels by 20 millimetres will prove a relatively cheap exercise in the long run.
"We need to be assured that we won't be making flooding worse."
The mayor, Cr Keith Rhoades, was all for a decision being made on the night.
"We've got to move forward with this project," he said.
The contouring option bridge was adopted by six votes to three, but Cr Kelvey, supported by Crs Hogbin and Bonfield, lodged a rescission motion in a bid to generate more debate at the next council meeting.
Later in the meeting when Cr Bill Palmer asked if council should consider some way to mark the 10th anniversary of the 1996 storm event, Cr McKelvey quipped the contouring bridge might just be the monument council would be remembered for.