December 5, 2014

A Century of Urban Sprawl in the United States

Time

1:40 p.m. – 3:00 p.m.

Location

1605 Tilia, Room 1103, West Village

Speaker(s)

Adam Millard-Ball, Assistant Professor, Environmental Studies Department, UC Santa Cruz

Abstract

The urban street network is one of the most permanent features of cities. Once laid down, the pattern of streets determines urban form and the level of sprawl for decades to come. We compute street connectivity metrics, such as the proportion of cul-de-sacs, at the level of individual road intersections for the entire United States, and merge them with land parcel records to create a new, high-resolution time series of sprawl for the past 100 years. Sprawl appears to have started well before private car ownership was dominant, and grew steadily until the mid-1990s. While recent urban developments continue to add to the stock of low-connectivity neighborhoods characterized as sprawl, new additions since the mid-1990s have become significantly more connected and grid-like than prior to 1990, in accordance with the prescriptions of New Urbanism. In this sense, the peak in sprawl in the US was over two decades ago. We analyze spatial variation in these changes and estimate their quantitative impact on vehicle emissions.

Biographical Sketch

Adam Millard-Ball is an assistant professor in the Environmental Studies Department at the University of California, Santa Cruz. A planner and an economist, Adam’s current research focuses on explaining the history of urban sprawl; cross-national patterns of land-use and transportation; and parking management. He was formerly a Principal with NelsonNygaard Consulting Associates.