Flood hazards are depicted in blue and purple in the new modelling maps. Graphic / Tauranga City Council
"Inaccurate" was the word of the day in Tauranga City Council's chambers yesterday.
It was how several submitters characterised citywide flood hazard modelling maps released last year.
Four independent commissioners, chaired by David Hill, heard day two of submissions on the council's proposed Plan Change 27, which takes a regulatoryapproach to reducing the risk to people and property of flooding from intense rainfall.
Plan Change 27 was publicly notified a year ago, and given legal effect. New one-in-100-year event hazard maps were released at the same time.
The plan change introduces regulations for the development of new and existing properties deemed at risk of flooding.
Many submitters yesterday took issue with the accuracy of the flood modelling, particularly for their own properties.
Fears were raised about the impact on property values and insurance costs of being labelled "floodable" and some said the predictions did not line up with what they had seen water do during storms.
Council staff offered to take another look at the modelling or do a reassessment of several of the properties raised.
Submitter Lincoln Taylor, an engineer from Matua, said in his view it was unreasonable for the council to rely on the "inaccurate" modelling to such an extent, or to use it to "impose inappropriate restrictions and costs on residents".
"The model, on a property-by-property basis, is wrong."
He said he had the council reassess the modelling for his own home and staff found it was wrong. He said knew of other areas on the map that had flooded badly in the past but had little or no modelled flooding. He did not know of any mitigation work.
He said an infrastructure-led approach was needed: "You might as well get on and own up to the fact that us ratepayers are going to have to fix this problem. It's expensive."
John Pullar, a Whakatāne District councillor, spoke on behalf of the body corporate of Sun Pacific Villas in Mount Maunganui.
He said he considered the council's regulatory response "unreasonable" and "unfair".
"It is an easy solution for [Tauranga City Council] but devastating for owners in terms of resale and insurance."
In his view, it would be more practical for the council to take some action to mitigate the flooding risk via infrastructure changes.
Commissioner Hill noted the panel had heard a lot of questions and comments questioning the integrity of the mapping. He put questions to several of the submitters about what alternatives they considered would be acceptable.
The submission hearing is set to continue until Friday.