Notes III

Carhenge, Alliance, Nebraska

©EOP

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.

Related articles by Zemanta

• Downstream residents dodge bullet after Lake Delhi dam fails (gazetteonline.com)
• Dam Fails in Eastern Iowa (nytimes.com)

Urban Water Supply

Fairmount Waterworks, Philadelphia, PA 1998

© EOP

Spending several days in Philadelphia earlier this week, I have not done much work on  the water course. The issue of water was not completely absent, for on a visit to the Philadelphia Museum (brown temple like building in the upper section of photo), we parked in a lot above the Fairmount Waterworks, some classic revival buildings of substantial architectural interest on the eastern bank of the Schuylkill River near downtown Philadelphia.With its museum honoring the city's waterworks, the building is also of substantial interest as a surviving element of one of the oldest municipal water supply systems in the world. Originally opened in 1815, the pumping station has been closed for over a century, but it marks the initial source of a reliable supply of clean water for the residents of the Pennsylvania city and the origins of the idea that a supply of potable water was essential for urban success.

Upstream from the waterworks and the dam on the Schuylkill is Fairmount Park. It was originally created to protect the quality of the city's water by limiting development of its watershed, an idea still very much in the forefront of urban water supply planning. Philadelphia today draws its water from a much larger area, but the green space remains one of the largest urban parks in the United States. A number of urban innovations had their origins in Philadelphia, including a fire department created through the efforts of Benjamin Franklin.Its growth to become one of the largest cities in the United States depended on increasing its water supply. Today's water system supplies a vastly larger population spread over a much larger land area than the Fairmount Park pumping station supplied. A good website called Philly H2O has all kinds of information about the city's water supply, including a great map collection.

Oil, Gas and Water

 Oil on the Surface of the Gulf of Mexico, 7 June 2010, Source: NASA Earth Observatory

The catastrophic oil leakage into the Gulf of Mexico would seem to be rather remote from issues to be discussed in the autumn course on water (though it may have direct bearing on the spring course when food supplies are to be examined; more on that at a later date), but the dangers from oil and gas spillage into bodies of water are not limited to salt water. There is a long and sad history of freshwater bodies contaminated by oil and gas leakage, and that history may have some additional catastrophic chapters before the age of hydrocarbons comes to its inevitable end. The dumping of raw petroleum and various byproducts was sadly common in the early years of oil exploration and exploitation in the United States, first in western Pennsylvania and Ohio and later in petroleum boom areas of California, Texas, Oklahoma and elsewhere. More rigorous laws have forced the petroleum companies to use greater care, and large spills on land have been rare in North America over the past half century. Small spills, on the other hand, are quite common. Recently there have been a number of reports of spillage along the Alaska pipeline. Comparable cases could be found almost everywhere that petroleum and natural gas are found close to lakes and streams. Only a few of the spills are catastrophic, but even a small spill can upset the local ecology and render water unfit for human or domestic animal use.

The Delaware is one of America's iconic rivers, and it is also the most threatened by drilling for natural gas. It was recently named one of the most endangered rivers in the United States as gas wells have been sunk into the Marcellus Shale, a natural gas rich geological formation that stretches southward from central New York State into Pennsylvania. Last week a major accident occurred with a large quantity of material, including drilling muck, spread across some Pennsylvania forest land near the river. There has been relatively little public notice of the event, and it has not figured in news reports from the major media sources. The accident points to the substantial dangers inherent in drilling for gas and oil on land. As the American Rivers report indicates, the Delaware River, flowing to the Atlantic where there are important fishing grounds and passing through some of the most densely populated zones of the United States, could be the recipient of huge quantities of toxic material should a spill occur in its Pennsylvania or New York State watershed.