Arrival to Christchurch, New Zealand
An earthquake investigation team arrived one day after the September 4th, M7.1 Canterbury Earthquake. We witnessed damage to historical downtown buildings and wide spread soil liquefaction failures in Christchurch. Miyamoto International sent a structural engineering team to investigate the extent and causes of the damage and assist people with our expertise immediately after the earthquake. The emergency response was immediate and effective. So far no fatality has been reported however, there are many untold stories of human tragedies. There are numerous businesses and people who will be affected for many months or years to come by this earthquake. We would like to share their stories and facts, so all of us can prepare for earthquake disasters we will eventually face.
This is a journal entry by Jeff Crosier, S.E.
Journal Entry #1
September 5, 2010
I arrived this morning in Christchurch, NZ the day after the M7.1 Canterbury earthquake centered near Darfield. When I left Los Angeles on Friday evening, the status was not clear as to the extent of damage in the affected area or even if the Christchurch airport was operational. The flight crew fortunately provided updates on the situation in Christchurch throughout the flight, before we landed in Auckland we knew the airport in Christchurch was open once again. I saw no visible damage at the airport with all services and stores open. The airport closure was to assess the condition of the runways and infrastructure of the airport.
Our assignment here is to investigate the earthquake damage and also assist people as we see fit. . As I drive from the airport, I get to see Christchurch for the first time, it is a beautiful city with many modern progressive buildings mixed well with 19th century architectural classics.
The City Center area of Christchurch has become the set up area for the Emergency Operations Center (EOC.) They have taken over the Art Center building which is a modern steel framed building with vision glass wall panels on all sides, it is a beautiful building with no apparent damage. I arrive downtown less than 30 hours after the earthquake and Urban Search and Rescue teams from Auckland have already been on scene and cordoned off many of the downtown blocks as well as marked off hazardous areas near damaged portions of buildings. The USAR teams are also working with Civil Defense workers to rapidly assess and post buildings for earthquake damage. They are using paper placards approved by the Christchurch City Council similar to those developed for the ATC-20 protocol that has been widely used in the United States and other parts of the world. I am very impressed that all of the damaged buildings in the downtown area have been or are being assessed and barricaded as necessary. There are very few people in the streets aside from the USAR teams and Police who are maintaining the street closures. The area is under curfew from 7 pm to 7 am. Though power has been restored to many of the buildings in the area, few businesses are open and those that are primarily coffee shops. I see many hand written signs on storefronts stating they were closed due to loss of power.
When I arrive downtown I meet up with our team member Marga Lamoreaux. She is a young American structural engineer who lives in Christchurch. I know her since she was the SEAOC president of the Cal Poly SLO student chapter that upon graduation came to Christchurch for graduate studies and then to start her career in structural engineering. It is great to see her again and she knows Christchurch well as well as all of the structural engineers that we keep meeting.
The damage we see downtown is primarily limited to the unreinforced masonry (URM) buildings. Many chimneys have collapsed and walls have pulled away from roofs where not adequately anchored. I understand that there is an ordinance in the works to mitigate the hazards of URM buildings here, but the program is not complete.
Once outside the City Center area, the damage becomes limited to the occasional URM wall collapse and chimneys for many residential buildings. From the City Center, we head to New Brighton to investigate reports of liquefaction. The reports turn out to be true, there are many areas we see that have liquefied and sand has boiled from the ground. There are many underground utility pipe breaks in the New Brighton area with water and sewer lines severed due to ground movement. Much of the New Brighton area seems to have suffered ground damage as it is adjacent to the sea. We discovered a gas station that had its slab and continuous edge footings that cover their underground gas tanks pushed out of the ground from liquefaction. I suspect that the tanks themselves may have been pushed up as the soil liquefied but we weren’t able to investigate the subterranean conditions. We also saw numerous cases of lateral spreading and vertical offsets of the soil and even a row of power poles that are leaning severely due to loss of support at their bases once the supporting soil has liquefied. The underground utilities may have been amongst the hardest hit in this area as there are numerous water and sewer line pipe breaks. The city of Kaiapoi has lost its water and sewer and has evacuated residents, as of now they are uncertain when those utilities will be restored. Marga and I tried to go there but Police had the town roadblocked and were not allowing passage.
My first impressions after one day is that the emergency response here is exceptional and that this plan has been carefully planned and teams have maintained training to have activated as quickly as they have. Also, the engineered buildings behaved very well. Tomorrow I plan to go to Darfield and other areas closer to the epicenter.