Cr Greg Petty is running as an independent in the seat of Heathcote, which runs from Wombarra up to Menai in Sydney's south.

He has drawn attention to Wollongong City Council's flood zone maps, which he says produce exaggerated flood risk results.

He said if elected he would call for a parliamentary inquiry into the issue.

"The residents of the Wollongong LGA have an expectation that council and state government agency flood plan studies and mapping are based on verified empirical data, reflect historically recorded flood levels, and do not unnecessarily negatively impact ratepayers, especially after the 1998 event in Wollongong," Cr Petty said.

He said the council's maps and modelling were sometimes based on an "ultra-conservative, poorly verified and now entirely outdated" policy for calculating whether drains and culverts become blocked in floods.

The result is neighbourhoods being listed as more at risk than they may otherwise be.

These views are shared by some senior hydraulic engineers familiar with Wollongong's geography.

"All flood studies conducted since 2002 have resulted in design flood levels that are completely distorted, are not based on historical levels, and as such, have sterilised valuable land, forced people's insurance premiums through the roof, and made the most basic renovation a complete nightmare," Cr Petty said.

He cited the example of Hewitts Avenue in Thirroul, where residents have had to plan for much higher floods than have ever occurred, and have watched insurance premiums "rocket" past $20,000.

"These matters demand a parliamentary inquiry," Cr Petty said.

The council has promised to review its blockage policy.