What keeps people living in areas know to be high hazard areas? I cannot answer since I am not one of them. [Living in the metro Washington, DC area has its risks, but most of them are not life threatening!!]
See: Racing the Clock and a Storm Way of Life in Tornado Alley. NY Times, May 24.
What keeps these people in their risky cities?
Recovery Diva 
Following Dr. Plodinec, I offer the first few lines from Pat Conroy’s The Prince of Tides:
“My wound is geography. It is also my anchorage, my port of call.
I grew up slowly beside the tides and marshes of Colleton; my arms tawny and strong from working long days on the shrimp boat in the blazing South Carolina heat. Because I was a Wingo, I worked as soon as I could walk; I could pick a blue crab clean when I was five. I had killed my first deer by the age of seven, and at nine was regularly putting meat on my family’s table. I was born and raised on a Carolina sea island and I carried the sunshine of the low-country, inked in dark gold, on my back and shoulders. As a boy I was happy about the channels, navigating a small boat between sandbars with their quiet nation of oysters exposed on the brown flats at the low watermark. I knew every shrimper by name, and they knew me and sounded their horns when they passed me fishing in the river.”
This, and variants on it, is precisely why many choose to stay in the SC Lowcountry. I suspect that there are similar reasons for many others in other disaster-vulnerable communities.
I moved to Charleston six weeks before Hurricane Hugo hit in 1989. Though I jokingly refer to that time as my “so much for southern hospitality” days–Hugo was no laughing matter. During my first few years here I had no doubt that if the area experienced another significant hurricane I would leave. Every year I dreaded it when June 1st, the beginning of hurricane season, rolled around. Life was low-level anxiety. i had some friends who moved here from other places who eventually yielded to that anxiety and left.
For my part, sometime in the late 90s (even as Hurricane Floyd hit the area) i began to embrace this place and grow some roots. I had learned how to catch shrimp and crab, how to cook grits that were actually delicious. I look forward to early morning walks on the beach. And, so, some 24 years later, here I find myself–not thinking about living anyplace else and yet understanding that my home is not only subject to hurricanes, but also earthquakes.
My point here is the same as John’s: There is just no objective accounting for how we come to settle in a place and find it more and more difficult to think about living some place else.
Claire,
There are at least two reasons why people tend to locate or rebuild in disaster-prone areas:
1. People like to live where it is beautiful – coastlines, mountains, river valleys.
2. People like to stay where they feel a sense of “homestead and attachment” – farms, urban neighborhoods, “home towns.”
In some cases, people live where they can afford to live. Historically, “cheap” land has often been in vulnerable areas. There is also the issue of “access” – to jobs, public transportation, and services. No telling how many individual reasons there may be that outweigh mitigation or recovery costs, especially when recovery costs are often subsidized.
The “stickiness” of community (according to my good friend Andy Felts). Memories – the currency of social capital – enrich us emotionally just as money enriches our material well-being. If you talk with those who could not return to NOLA after Katrina you will hear a sense of loss every bit as gut-wrenching as talking to a bankrupt, even if it was the comparative squalor of the Lower Ninth Ward they left behind. It is those memories of people and places that tie us even to risky locales. We hear their haunting echo in Gov Christie’s vow to rebuild the Jersey Shore so his kids could experience what he once knew. We see their power in the stubborn resolve to rebuild Greensburg, KS. Intellectually incomprehensible perhaps, but carrying a kind of cockeyed nobility as well. Deep in our gut, we all know that our human connections mean as much to us as our money; we all know that to lose those connections is to lose an important part of ourselves. Part of the saddening maddening wonderful humanity we all share.