Ecommerce and Logistics Sprawl: A Spatial Exploration of Last-Mile Logistics Platforms

The rise of ecommerce helped fuel consumer appetite for quick home deliveries. One consequence has been the placing of some logistics facilities in proximity to denser consumer markets. The trend departs from prevailing discussion on “logistics sprawl,” or the proliferation of warehousing into the urban periphery. This study spatially and statistically explores the facility- and region-level dimensions that characterize the centrality of ecommerce logistics platforms. Analyzing 910 operational Amazon logistics platforms in 89 U.S. metropolitan statistical areas (MSAs) between 2013 and 2021, this study estimates temporal changes in distances to relative, population centroids and population-weighted market densities. Results reveal that although some platforms serving last-mile deliveries are located closer to consumers than upstream distribution platforms to better fulfill time demands, centrality varies due to facility operating characteristics, market size, and when the platform opened.

Ecommerce has transformed the “consumption geography” of cities. These transformations have major implications for shopping behaviors and retail channels, last-mile operations and delivery mode choice, the management and pricing of competing uses for street and curb space, and the spatial ordering and functional role of logistics land uses. In the latter case, researchers have observed a diversification of logistics platforms to more efficiently serve home delivery demand. These platforms range from “dark stores” and “microfullfilment centers” that fulfill on-demand deliveries and omni-channeled retail without a consumer facing storefront, multi-use urban distribution centers that convert unproductive sites (e.g., abandoned rail depots) to more lucrative land uses, and “microhubs” that stage transloading between cargo vans and e-bicycles suited for dense urban neighborhoods.

Logistics spaces play an important role in improving urban livability and environmental sustainability. Planning decisions scale geographically from the region-level to the curb. Facilities such as urban consolidation centers and loading zones can mitigate common delivery inefficiencies, such as low delivery densities and “cruising” for parking, respectively. These inefficiencies generate many negative externalities including climate emissions, air and noise pollution, congestion, and heightened collision risks, especially for vulnerable road users such as pedestrians and bicyclists. Limited commercial data has made it difficult, however, to observe spatial patterns with regards to ecommerce logistics platforms.

Using detailed proprietary data, this paper explores the evolving spatial organization of ecommerce logistics platforms. Given the company’s preeminence as the leading online retailer in the U.S., the paper presents Amazon as a case study for understanding warehousing and distribution (W&D) activity in the larger ecommerce space. Utilizing proprietary data on Amazon logistics facilities between 2013 and 2021, this research explores the geographic shape and explanatory dimensions of ecommerce within major U.S. metropolitan areas. In the following section, this study defines the state of research related to broader W&D land use and its implications to ecommerce’s distinct consumption geography. Afterwards, two methodologies for measuring logistics centrality are tested: a temporally relative barycenter-based metric, the prevailing method in literature, and another GIS-based, population-weighted service distance metric. The two measurements reveal nuances between facility- and region-level differences in the spatial organization of ecommerce platforms, which has yet to be fully researched. After presenting results from an exploratory regression analysis, this study discusses implications for future urban logistics land use and transport decisions.