Midwest Flooding – Collection of Links
Press Releases
New Study Shows Odds High for Big California Quakes
Released: 4/14/2008 12:02:15 PM
California has more than a 99% chance of having a magnitude 6.7 or larger earthquake within the next 30 years, according scientists using a new model to determine the probability of big quakes.
The likelihood of a major quake of magnitude 7.5 or greater in the next 30 years is 46%-and such a quake is most likely to occur in the southern half of the state.
[Editor] At Left: Figure 1. The colors on this California map represent the UCERF probabilities of having a nearby earthquake rupture (within 3 or 4 miles) of magnitude 6.7 or larger in the next 30 years. As shown in the table, the chance of having such an event somewhere in California exceeds 99%. The 30-year probability of an even more powerful quake of magnitude 7.5 or larger is about 46%. [/Editor]
Geologic Hazards
Flooding in Supai Canyon
There have been a number of reports on the flooding in Supai Canyon, near the Grand Canyon this past weekend. I think the best description of the event and the subsequent rescues was from the AZ211 website which I found by way of the Arizona Geology Blog (quoted after the break). The flood was impressive. I hope the areas near Havassu Falls and Mooney Falls were not too heavily damaged. I was fortunate enough to hike and camp that location back in College, the travertine is just amazing and makes the water so green. Mooney Falls and the area downstream are particularly breathtaking. [Photo credit: National Parks Service]
Many reports I’ve seen attribute the flood the result of the failure of the Redlands Dam. But again, the Arizona Geology Blog quotes the National Park Service as saying that the dam is a minor one meant to create a pond for livestock and wasn’t a significant factor in the flooding. The latest reports I saw was that 11 hikers who were missing were located today (by way of Geology.com)
Geologic Hazards
New Orleans Repeats Deadly Levee Blunders
That is the title of a Seattle Post-Intelligencer article on post-Katrina levee issues in New Orleans (by way of ASCE Smart Brief). I think the article is somewhat sensationalized, but they do cite some interesting parallels between the levee reconstruction efforts made after Katrina and the levee construction/reconstruction that occurred after Hurricane Betsy in 1965.
The article also discusses a recent US Army audit with some disturbing although not unexpected findings:
An initial September 2010 target to complete the $14.8 billion in post-Katrina work has slipped to mid-2011. Then last September, an Army audit found 84 percent of work behind schedule because of engineering complexities, environmental provisos and real estate transactions. The report added that costs would likely soar.
A more recent analysis shows the start of 84 of 156 projects was delayed – 15 of them by six months or more. Meanwhile, a critical analysis of what it would take to build even stronger protection – 500-year-type levees – was supposed to be done last December but remains unfinished.