A Tragedy in Haiti
On January 12, a 7.0 seismic event centered close to Haiti’s capital, Port Au Prince, caused massive devastation. The collapsed structures and untreated injuries may cause up to 200,000 deaths.
The past few days have been a nightmare for people on the ground. The EQ knocked out much of the country’s fragile infrastructure. Haiti was a nation that was already in need of major assistance, having experienced 4 full-scale hurricanes last year and decades of political instability. A 7.0 EQ is absolutely a major event, and coming so close on the heels of last years problems is just horrible.
To put it in perspective, California’s Northridge EQ in 1994 was one of the USA’s worst disasters causing $20B worth of damage and it only registered a 6.7 magnitude. Haiti’s EQ caused strong lateral movements, and judging from the USGS map the accelerations were almost as strong as gravity. This is the structural equivalent of taking a building and turning it on its side, again and again.
Very few buildings can survive this type of movement undamaged. Haiti was even worse off because of their building materials. Many of the buildings were built from unreinforced, hand-mixed concrete blends. The images on TV show the results well enough, the TV crews probably don’t even need to look very hard to find examples.
As a structural engineer, it is always difficult to see the problems caused by improper construction and to know that many of the problems could have been avoided. Of course once an earthquake hits, engineers are powerless.
Using a list of simple rules engineers can easily design buildings that, for the most part, will preserve life safety. Designers of critical structures such as police buildings, hospitals, and bridges know in advance that they must make sure the structure will be operational in even the worst of events. The hospitals, bridges, and government buildings in Haiti appear to be worse off than other buildings, even.
So why do events like this happen? Engineers understand earthquakes, but that is only one step in the chain of safe construction. Simply stated, it is a political failure. Building codes are rolled back by politicians, with the excuse that they are too expensive. Contractors pay bribes to inspectors to pass suspect materials and shoddy workmanship. Engineers are asked to turn a blind eye in the name of patriotism. The problem with this “build quickly” theory is that the buildings remain and the legacy of poor construction becomes a ticking time bomb.
I am not trying to lay this problem at the feet of Haitians. I doubt many of them knew they were sitting on a fault line. They probably didn’t understand that reinforcing is required in columns for earthquake resistance. The engineering community needs to make a greater effort to encourage seismic resistant buildings in developing nations.
The engineer’s sole weapon against natural disasters is good design. If engineers aren’t proactive in the political realm or if engineers cede their responsibilities, then they will fail in their duty to protect the public welfare.
Anyone interesting in helping the efforts in Haiti should donate to the American Red Cross disaster relief foundation. Engineers wanting to donate specific skills should go to the ASCE Disaster Assistance page.
The observation I heard–simple, but powerful–was the earthquakes don't kill people; bad buildings do. I was amazed when just yesterday I learned that Haiti actually did have building codes. Enforceability is of course a huge problem in a country where 80% of the population is in severe poverty, many of them living in informal housing (which of course is badly built). Money will always be a barrier to good construction in Haiti, but so will political will, since this is the first major quake there in two centuries. I've often wondered how cities like St. Louis and Memphis will do when New Madrid gets hit with the next big one.
It's absolutely true that most earthquake deaths are preventable. Of course, a nation like Haiti would need a different solution from our own building code. A lot of work has been going into simple construction rules that prevent collapse.
Obviously any disaster like this serves as a good wake-up call to other countries to take this seriously, so maybe seismologists can use this as an opportunity.
Here in the US, a lot of engineers have been concerned about similar situations where a large city is directly above a fault line capable of large movements over long recurrence intervals. The New Madrid Seismic Zone is a great example, but is not the only one.
In the case of New Madrid, I think St. Louis would fare much better than Port-Au-Prince. Much of the city's essential services have been reinforced. Newer research suggests that the New Madrid Zone may not present the hazard that it once did. While that is welcome news for the city, it doesn't change the facts that every US city must take this issue seriously.
A large earthquake happening under a US city is bound to happen. Likely culprits include the Seattle Fault that runs across Puget Sound and a repeat of the 1886 Charleston event.
Structures in the US are rarely built to escape an event undamaged. Engineers are only asked to keep the buildings standing, not operational. Thus, any event will cause a huge amount of property damage but relatively few deaths compared with what happened in Haiti.
Very well said. I've been wanting to post an article about Haiti but have yet to find the time. I've heard a lot of people ask about what we might learn, as structural engineers, from the Haiti tragedy. Unfortunately, I think the answer is not much. Many of the structural failures, as you said, were avoidable. I think, from the perspective of the structural engineering community, a tour of Haiti would essentially be a tour back in time. We've already learned those lessons; we may have built them that way at some time in the past but have already seen those un- and undereinforced structures fail.
Brett – Well said, I completely agree.