An earthquake is the biggest hazard risk for Hamilton city, according to a study into what major facilities could be damaged in an emergency.
This week’s Environment Waikato Environment Committee meeting heard that ground shaking and liquefaction from earthquakes was the event likely to cause the most hazards in the city, as an earthquake could affect every part of the city causing deaths, widespread damage to buildings, utilities and facilities.
Waikato University Masters student Hugh Blackstock completed the research with support from a Millennium Scholarship from Environment Waikato. The results will form the basis of Hamilton’s emergency management planning by identifying critical facilities and allowing the city to measure their vulnerability.
As well as earthquakes, ash fall from a volcanic eruption, tornadoes and the release of hazardous substances were also a potentially major threat to a large part of the city. Ash could cause roofs to collapse and disrupt crucial facilities such as the water treatment station and wastewater treatment plant.
Tornadoes were random and could cause extensive damage to all structures as well as hurting people. In a hazardous substances spill, or an explosion of acetylene or LPG vapour much of the city would be affected. Facilities which could be affected included the water treatment station, bridge approaches and wastewater treatment plant and pipes next to the Waikato River.
These would need further in-depth investigation to determine which would be most vulnerable, Hugh Blackstock said.
“Technological events have shown the potential to cause many hazards but the processes behind such events are poorly understood and records pertaining to the storage of hazardous substances is incomplete.”
He said Hamilton’s potential vulnerability to hazards was heightened by its proximity to the Waikato River, which exposed it to flooding and to the threat of high winds as the river acted as a channel.
The study will be used with Environment Waikato’s own hazard mapping, lifelines studies and flood warning and hazard information to develop strategies to protect specific sites.