Effects of Urban Sprawl on the Vulnerability to a Significant Tornado Impact in Northeastern Illinois

Abstract

A sprawling U.S. population continues to spread into the fringes of urban development placing both populations and property in areas that were once largely unoccupied. Population tallies, housing unit totals, and housing values for 1990 and 2000 are examined to determine the extent to which this growth has affected the tornado hazard in northeastern Illinois. The growing town of Plainfield, Ill., located southwest of Chicago, is examined to determine how vulnerability to a tornado impact has changed in the town since an F5 tornado stuck the community in 1990. The population and housing data indicate an increase of 8,629 persons and 3,058 housing units affected if the tornado were to have occurred in 2000 rather than 1990. Estimations of housing value affected by the Plainfield tornado indicate a 50% increase in 2000 compared with 1990 values. In addition to studying the impacts on Plainfield, four other scenarios are examined in suburban Chicago counties using the 1990 Plainfield tornado as a model for a potentially devastating strike. The large increase in total value of homes affected for each scenario highlights the overall increase in wealth throughout the study area, specifically along the urban fringe of development. The physical vulnerability throughout the study area has increased with the rise in population, but the most socially vulnerable areas appear to remain in the older urban centers.