Using Street Intersection Density to Model Urban Sprawl: The Case of Las Vegas

This project investigates the use of street intersection density to model urban sprawl in Las Vegas from 1992 to 2006. The methodology is based on four premises: 1) streets are a necessary prelude to development; 2) intersection density is a bellwether of development at the edges of a city; 3) intersections can be derived from Census TIGER (Topologically Integrated Geographic Encoding and Referencing system) files using data processing routines; and 4) the updating cycle for TIGER is useful for measuring change on an annual basis.

Street intersection points (latitude/longitude) were derived from TIGER data for the Las Vegas area for 1992, 1998, and 2006. The points were loaded into a GIS for analysis where intersections per square mile were calculated. A grid generated within the GIS was used to produce a geostatistical surface (kriging) for each of the test years. Results showed that the methodology produces a pattern of urban sprawl over time acceptable for visualization and analysis. Change over time was analyzed with the best-fit curves of the relationship between distance from the center of Las Vegas and intersections per square mile. Anomalies were found to be a function of terrain, protected areas, and major transportation arteries.

Courtesy of University of Wisconsin–Eau Claire.