Quake-prone buildings concern
Thousands of Christchurch buildings could prove dangerous in future earthquakes, and a new campaign is targeting those that could collapse on the public.
Under new laws all councils must identify quake-prone commercial and multi-unit residential buildings, and order owners to strengthen or demolish them within set time frames.
Christchurch City Council estimates up to 10,000 Christchurch buildings, including those built before 1974 and many others, are potentially affected.
The council is now launching a public consultation programme to find quake-prone buildings near busy roads or walkways, or on routes of strategic importance, which it must target under the new laws.
Despite large numbers of demolitions and repairs since the earthquakes, Christchurch has the second-highest number of listings, behind Wellington, on a national register of quake-prone buildings. This is due to engineering assessments done after the earthquakes to identify at-risk properties.
The 588 buildings already on the Christchurch list include buildings at Christchurch, Burwood and Hillmorton hospitals, central city buildings including the former chief post office and old Odeon theatre, buildings at schools including Christchurch Boys’ and Shirley Boys’ high schools and St Margaret’s College, shopping complexes such as The Palms, both the city’s cathedrals, factories, fire station and office buildings, and a raft of small buildings from toilet blocks
to sports pavilions and community libraries.
As a high-risk area, Christchurch has 21⁄2 years to assess and
71⁄2 years to repair high priority buildings, such as hospitals, schools, emergency sites and central city buildings.
Lower priority buildings must be assessed within five years and strengthened or demolished within 15 years. Owners will also need to display a notice warning the public of the building’s quakeprone status.
Buildings left damaged and dangerous by the earthquakes are already required to be cordoned off until repaired, so are not included in the new process.
Ann Brower, who was the only survivor when a building collapsed on a bus in the February
2011 earthquake, made submissions to the Government before the new law was passed and later said she was ‘‘delighted’’ that it would force owners to strengthen buildings sooner.
A total of 40 people died in the Christchurch 2011 earthquake because of the failure of unreinforced masonry buildings.
The council’s head of building consenting, Robert Wright, said although about 4000 buildings had been assessed, an estimated 6000 remained to be done.
About half the owners who had been asked for detailed engineering evaluations (DEEs) by Canterbury Earthquake Recovery Authority (Cera) after the earthquakes have provided them.
Wright said those reports would suffice as the detailed seismic assessments (DSAs) now required by the new laws.
Although the council still had many quake-prone buildings to identify, owners in the city ‘‘recognised the risk aspect’’ better than those in other centres.