All flood studies across the Wollongong area may need to be reviewed and potentially rewritten, the city's councillors have decided.
With a review taking place into the council's culvert blockage policy some time this year, councillors have realised how far its consequences could reach.
At Monday night's meeting, Cr Greg Petty's call for the Woonona flood study to be reviewed was voted down, as councillors wanted to await the outcome of the blockage policy review.
Adopted in the wake of Wollongong's 1998 floods, in which many culverts became blocked with debris, this policy has been blamed for sending insurance premiums skyrocketing.
This is because it can exaggerate the risk of flooding by assuming all culverts and drains are 100 per cent blocked during a significant rain event.
Cr Petty told Monday's meeting he was convinced there was "a new co-operation to get this right" within the council.
"We are acting on incorrect information," he said.
"Now we know the information we need to fix it."
Cr Janice Kershaw said the blockage review could have far-reaching consequences for the flood studies, which inform the management plans in each catchment area.
"I would imagine every flood study that was done would have to be reviewed," she said.
"Not just Woonona, all of them."
About 30 residents affected by the policy watched from the public gallery on Monday night.
Cr David Brown said council should not be blamed for insurance premiums rising, as that was a matter between individuals and their insurance companies.
"It might sound harsh but that is your personal business," he said. "What we do with our flood data is for our business. What other people do with it is their business."
He said the council should proceed cautiously given the potential for injury and property damage from flooding.
Meanwhile, the council has now said the Woonona flood study is not being reviewed yet - despite a spokesman telling the Mercury last Friday that this review was already under way.
It had become an issue after the blockage policy had been blamed for producing a skewed result for some properties in the catchment area there.
On Wednesday a council statement said the Woonona study would have to wait.
"The blockage policy is under review, but not the flood study for the combined catchments of Whartons, Collins and Farrahars creeks, Bellambi Gully and Bellambi Lake which was completed in March 2011," it said.
"As per council's resolution on Monday night, once the review of the blockage policy has been completed, a decision will be made whether the catchment studies also need to be reviewed and, if necessary, amended. Right now, council is developing a process and timeframe for the review of the blockage policy."
Under Monday's resolution, an article will be written on the council's website addressing residents' concerns, and briefings on the issue by council staff will be made available to neighbourhood committees.
From the moment the first raindrop hits the ground, residents of Surfrider Caravan Park in Barrack Point prepare the emergency flood kit and get ready for evacuation.
After the floods of March 21, 2011, when the park was inundated with water that reached chest height, residents feel they have been "left out on a limb" regarding future flood planning for the area.
Over the past four years, Shellharbour City Council has been working on finalising a flood management plan for the area, originally estimated to take three years.
Frustrations are mounting among residents and park management because plan proposals have been pushed back until August this year.
"We can't be left out on a limb or we'll just float off if there is another flood," resident Marie McCormick said. "Every time it rains I get out my gumboots, raincoat, mobile phone and torch and keep my eyes on the lake.
"Most people living in this park are elderly and we're all on our tippy toes."
Ms McCormick formed a flood committee for the park residents which included a notification and evacuation process in the event of a flood.
The Elliot Lake-Little Lake Floodplain Risk Management Study and Plan reports were presented to the committee on March 19 and a council spokesperson said the council was finalising the meeting minutes to go up on the council's website.
"The delivery of the Elliot Lake-Little Lake Floodplain Risk Management Study and Plan has been delayed due to the extensive amount of data collection undertaken for the study, altered scope of the study and long flood model run times associated with model calibration during the modelling stages of the study," the spokesperson said.
Park owner Barry Creary said the delay had prevented him from starting improvements to the park.
"I'd like to raise the cabins up, but council won't give me a flood height until the report is done," he said.
"Council promised they would do something to relieve the problem and we were told investigations would take three years and still nothing has happened."
- by Eliza Winkler