A preliminary seismic assessment of Tauranga City Council’s Spring Street car parking building has signalled a need for a further detailed assessment and initial work to address aspects which may not meet Building Act earthquake rating standards for existing structures.
Corporate Services General Manager Paul Davidson said a report received by the council today (30 June) reflects a precautionary approach based on learnings from the Christchurch and Kaikoura earthquakes.
He said the expert engineering advice the report is based upon did not highlight any risks which would affect the continued use of the building. “The building’s date of design means that a seismic assessment was not a requirement, but experience with the precast concrete floor construction method used has highlighted the need for a proactive approach to ensure the structure is safe for community use, if a major earthquake did occur,” he said.
While the assessment indicated that the structural walls and seating of the precast floors are likely to meet the required seismic resistance standard for existing buildings, work was required to secure the block wall on the north-eastern side of the building. Planning is underway to have that work completed floor-by-floor, at an estimated cost of $141,000. Building users will experience some minor localised disruption when that work progresses.
A detailed seismic assessment, which will include a geotechnical investigation of ground conditions, has also been initiated and is expected to be completed in around three months. This will confirm any other work required.
The Western Bay of Plenty area sits within the medium seismic risk area defined by MBIE, and as such, the statutory timeframe for completing any required strengthening is relatively long at 25 years.
“We therefore have time to assess and implement any remedial works which are considered appropriate, in a manner which will ensure the long-term safety of the building and minimise any impacts on CBD parking availability,” Mr Davidson concluded.