A snapshot of Tauranga's slope hazard risk mapping featuring The Lakes and Tauriko area. Image / TCC
A snapshot of Tauranga's slope hazard risk mapping featuring The Lakes and Tauriko area. Image / TCC
Tauranga City Council is under fire for issuing ‘‘inaccurate’’ slope hazard maps that a property industry group claims have caused land sales to fall through and settlements to be withheld.
Tauranga’s Urban Task Force believes many property owners are unaware their Land Information Memorandum (LIM)has now been tagged as having a slope hazard based on “outdated” maps from 2019. It believes the “serious” issue needs to be “urgently addressed”. It also criticised the council commission for not agreeing to meet on the issue.
However, the council’s chief commissioner says some of the criticism is “uninformed” and the task force should focus on “working co-operatively with the people who can address and resolve their concerns”.
Urban Task Force is a collective of the city’s property developers, property owners and business communities and its comments come after the council sent more than 1300 letters to property owners in October informing them local slope hazard zones were updated. Drop-in information sessions were also held.
Slope hazard maps identify areas of either existing or potential slope instability. Landslides could occur in heavy rain or earthquakes, or during land development activities such as earthworks.
Chairman Scott Adams said the group was “deeply disturbed” by the updated warnings.
Adams said some properties, such as the newly built Winstone Wallboards - GIB Factory, had significant earthworks since 2019 when data for the maps was collected.
“There are massive implications if the accuracy of the data is not correct. Some of the areas concerned ... are now flat as a pancake. But TCC have put this slope stability clause over the property,” Adams said.
He said the maps were “clearly wrong and inaccurate” and there were “numerous sites” in Tauriko included in the mapping that contained no slopes.
Adams said the task force generally supported the council’s plans to update natural hazard records.
“However, our review of this recent mapping leads us to conclude that there are a number of problems with the accuracy of the maps and the duty of care applied by both the consultants and the council staff involved,” Adams said.
A snapshot of Tauranga's slope hazard risk mapping featuring The Lakes and Tauriko area. Image / TCC
An aerial view of Winstone Wallboards, located at Kaweroa Drive Tauriko. Photo / Supplied
Adams said, in his opinion: “Clearly, there is a question to be asked around competency here, as council staff are fully aware that the area has been redeveloped through recent subdivision resulting in significant landform change to create flat residential building sites supported by geotechnical completion reports which certify the lots.”
Adams said, in his view, geotechnical completion reports - which certify lots - superseded the slope hazard mapping but appeared to have been “ignored”, as were geological profile, vegetation, drainage, and engineered improvements.
The task force previously raised similar concerns about the accuracy of the council’s Plan Change 27 to address flooding and areas such as Kennedy Ridge at The Lakes was now acknowledged as a reassessment area. The same subdivision was now subject to the slope hazard mapping which the task force considered to be a ‘‘double whammy”, he said.
“The property development community is deeply disturbed by these inaccuracies and UTF members now face significant costs as a result, including sales needlessly falling through,” Adams claimed.
Adams also claimed settlements were being withheld on business land until the mapping errors were resolved.
“This is a serious issue which must be urgently addressed.”
Urban Task Force chairman Scott Adams, pictured at the Panorama Towers build in November, says there are concerns with recent slope hazard map data issued by Tauranga City Council. Photo / Alex Cairns
Adams said the task force requested an urgent meeting with the commission but was told by chairwoman Anne Tolley the matter was not a governance issue.
Adams said, in his opinion: “If council’s governance cannot ensure staff are doing their jobs with a duty of care, based on accurate information ... then this does fall from the top.”
In response, Tolley told the Bay of Plenty Times the task force’s criticism of the council’s governance was “uninformed”.
“The issues UTF has raised are highly technical and should properly be dealt with by geotechnical professionals. Council staff with the appropriate professional backgrounds were already scheduled to meet with UTF early in 2024 and the requested meeting would not have achieved any useful outcome.
“Rather than making overblown claims, UTF should focus on working co-operatively with the people who can address and resolve their concerns,” Tolley said, in her view.
Council general manager of infrastructure Nic Johansson said the slope hazard maps were an update to those created 20 years ago and were based on data from 2019, the latest data available.
Commission chair, Anne Tolley, pictured at a Tauranga City Council meeting, says issues raised by the Urban Task Force are 'highly technical'. Photo / Alex Cairns
The estimated project cost for the updated maps and the landslide susceptibility study, done at the same time, was $480,000.
Asked what steps were taken to ensure the maps were up-to-date, fair, and an accurate representation of Tauranga, particularly the newly developed Tauriko area, Johansson said the council was working on this.
“Council has been in touch with the GIB factory and explained that we are in the process of updating the slope hazard zone map for this property as a result of the earthworks undertaken,” he said.
The council was aware of two other properties where earthworks changed the slope hazard zone maps, he said.
Anyone in a similar situation was invited to contact the council to ensure their information was updated, if appropriate, he said.
Johansson said the slope hazard maps did not supersede geotechnical completion reports, or any other site-specific mitigations or geo-professional reports undertaken for a property.
“This is covered in LIM reports with a statement that any further development may need to be supported by a report from a Category 1 Accredited Geo-professional and subject to stormwater design.”
If someone was selling their property and had concerns about a slope hazard zone, they could contact the council at naturalhazards@tauranga.govt.nz, he said.
A Winstone Wallboards spokesperson said it was aware of the issue and was working constructively with the council “to rectify the error and make the required changes to our property report at LIM”.
The consultants were approached for comment.
Kiri Gillespie is an assistant news director and a senior journalist for the Bay of Plenty Times and Rotorua Daily Post, specialising in local politics and city issues. She was a finalist for the Voyager Media Awards Regional Journalist of the Year in 2021.
