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In the posting about dams, I failed to note one major issue, the possibility of failure. Well-engineered dams rarely fail, but poor engineering, extreme weather events and lack of proper maintenance can lead to failures. In a few cases so can bad water management as illustrated by the first pages in Powell's Dead Pool, where the author describes what could have been a catastrophic failure of Glen Canyon Dam on the Colorado River. Under the worst of circumstances, a catastrophic failure can lead to hundreds or even thousands of casualties. The most famous dam failure in the United States was at Johnstown, PA in 1889 when a badly maintained dam broke and killed 2,200 people. (That same benighted city had further floods in 1936 and again in 1977, devastating to property but not nearly as deadly for people, and neither was the consequence of a dam failure but rather of extreme weather.) Two days ago a small dam in Iowa collapsed after torrential rains. Knowing the failure was likely, deaths were apparently avoided, but several downstream towns had to be evacuated, and there was substantial property damage.
The St. Francis Dam, a water supply dam built in the early 1920s and designed by the famed California water engineer William Mulholland, catastrophically failed on 12 March 1928 due to an engineering error. The ensuing flood killed 450 people and washed away towns and farms in the Santa Clarita Valley NW of Los Angeles. Another badly engineered dam failure was the collapse of the irrigation retention Teton Dam in Idaho in 1976 leading to 11 deaths and tremendous property damage downstream (see some pictures of the collapse on the website of a civil engineering faculty member at San Diego State University. Driving through the area later that summer, I stopped in Rexburg, Idaho to witness some of the devastation, but I have not scanned my slides as yet).
Shortly after posting the piece on glaciers yesterday, I read the New York Times (NYT) Sunday 25 July issue. While I am no fan of their regular columnist Thomas Friedmann, he has an interesting op-ed on global warming worth a read. This has been one of the hottest summers ever recorded in the eastern United States, and if current trends continue it could be the hottest yet recorded. Despite that heat (which it must be noted may be completely unrelated to climate change) the Senate has killed even the feeble climate legislation pending before it. Perhaps that is all to the well, for sometimes half measures like those in the bill now dead are worse than no action at all, but the lack of attention to the matter of climate change and the overuse of petroleum products in a hot summer with the Gulf oil gusher only temporarily capped is quite disturbing. It would seem those topics should be the subject of a national frenzy and demand for action. This morning's NYT has a good piece by their regular columnist and Nobel laureate Paul Krugman bemoaning the Senate's action, or or more exactly their lack of action placing a substantial share of the blame on the unprincipled ex-presidential candidate McCain and showing how the demands of the coal and petroleum oligopolies have trumped the public interest.
More water woes in the DC area. The drought may have broken for a time with heavy rains and strong winds accompanying a thunderstorm yesterday afternoon. The storm led to numerous electrical supply problems, and one facility loosing power was a major filtration facility of the Washington Suburban Sanitary Commission causing it to once again issue mandatory water usage limitations for Montgomery and Prince Georges Counties. While water supply systems are often discussed in the abstract and without reference to other elements of urban infrastructure, storms and other catastrophic events illustrate how interdependent those elements are.
