Multiple Dimensions of Sprawl: How Does LA Stand Up?

1. Multiple Dimensions of Sprawl: How Does LA Stand Up? George Galster, Wayne State University Royce Hanson, U. Maryland-Baltimore Co. Hal Wolman, George Washington U. Presented at the Conference: “Planning in the Post-Sprawl Era” University of Southern California, Nov. 30, 2001

2. Overview of Presentation • Sprawl has multiple dimensions • Possible to develop meaningful, objective measures of multiple dimensions of sprawl • Despite its lack of predominant core, LA is NOT very residentially sprawled relatively on most dimensions; it’s well above-average in housing density and proximity

3. Density Continuity Concentration Compactness Centrality (Mono-)Nuclearity Mixed Uses Proximity Dimensions of Sprawl

4. A Definition of Sprawl A pattern of urbanized land use exhibiting low levels of some combination of the aforementioned dimensions

5. Density The average amount of the given urban land use per areal unit of developable land

7. Concentration The degree to which a given urban land use is located disproportionately in relatively few square miles of the developed area

9. Centrality The degree to which a given urban land use is, on average, located close to the core of the developed urban area

11. (Mono-) Nuclearity The degree to which development is characterized by a single-node pattern of the given urban land use

13. Proximity The degree to which observations of a single (or different) urban land uses(es) are close to each other across the developed area

15. Measuring Sprawl: A Prototype • 13 Urbanized Areas • 5 Dimensions of sprawl operationalized • Housing Units (HUs) is land use considered • GIS used to construct database of HUs in one square mile grids, extracting from 1990 Census block files • Z-scores calculated for individual sprawl dimensions, plus unweighted average index

17. Prototype Measures of Sprawl • Density: # Housing Units / Square Mile • Concentration: Dissimilarity of Housing Units vs. Land Area Across Grids (Delta Index) • Centrality: Inverse of Ave. Distance of HUs from City Hall, Weighted by Square root of HUs • Nuclearity: % of HUs in all Nodes (grids in top 1% of HU density) located in Contiguous Core • Proximity: Inverse Ave. Distance between HUs, Standardized by Ave. Grid Centroid Separation

18. Sprawl Rankings: Least to Most

19. Are There Sprawl Archetypes? Lesson: Density alone does not sprawl make (nor does any other single dimension)

20. Urbanized Areas’ Profiles of Residential Sprawl Measured on Five Dimensions StandardizedIndicators Expressed as Proportional Differences from the Sample Mean Source: Constructed from data reported in George Galster et al (2000), Table 1

21. Future Directions I Expand Study Area Beyond Urbanized Area Add grids within PMSA/UA counties having: 30%+ commuters to UA and 60+ housing units

23. Future Directions II Use U.S. Geological Survey’s NLCDB: Residential & non-residential uses Vacant but “developable” land “undevelopable” land

24. Conclusions • Possible to develop meaningful, objective measures of multiple dimensions of sprawl • Despite its lack of predominant core, LA NOT very residentially sprawled relatively on most dimensions; well above-average in housing density and proximity