Email Battle Over Sprawl And Density Rages

The Sierra Club, Demographia and Thoreau Institute battle it out over a new "sprawl calculator."

1 minute read

June 22, 2001, 11:00 AM PDT

By Chris Steins @planetizen


The Sierra Club sent an email advertising its new web-based "Environmental Impacts of Sprawl Calculator," which compared the results for a neighborhood developed at what the Sierra Club called an "Efficient Urban" density of 500 housing units per acre and to one housing unit per acre "urban sprawl". In response, Wendell Cox of the consulting firm Demographia posted a satirical email to two mailing lists noting that the 500 unit per acre density assumed by the Sierra Club is 3.4 times the highest density census tracts in Manhattan and more than double the most dense wards of Mumbai (Bombay) and Kowloon (Hong Kong), which are generally considered to be the most dense communities in the world. Soon thereafter, Thoreau Institute economist Randal O'Toole posted an email taking the arguments somewhat further. Mr. O'Toole's post was converted into a Thoreau Institute Vanishing Automobile commentary, which is also reprinted. Shortly after the Cox and O'Toole postings, the Sierra Club changed the "Environmental Impacts of Sprawl Calculator," to exclude the 500 units per square mile column and to replace it with three columns with lower densities, the lowest of which is "efficient suburban," at 10 housing units to the acre. The entire fascinating email exchange and articles are documented on the Demographia website.

Thanks to Chris Steins

Friday, June 22, 2001 in Demographia

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