Urban stream deserts: Mapping a legacy of urbanization in the United States

• We map urban stream deserts (UrbSD) within 11 Megaregions of the United States.
• These UrbSD accommodate 73 + million residents within 11, 400 km2 of urban land.
• Detroit and Chicago have some of the largest UrbSD in the U.S.
• UrbSD are core areas of urbanization, with excessive impervious surface coverage.
• UrbSD are unique, but ambiguous, components of the urban ecosystem.

Protecting, as well as restoring, natural resources within the urban landscape has environmental and economic importance, especially as the global population continues to shift towards urban areas. One extreme legacy of rapid development and urbanization is stream burial. Here, riverless urban areas are mapped in 11 Megaregions within the United States, with additional focus on the Great Lakes, using a semi-automated, geoprocessing workflow completed within ArcMap10.2. Combining U.S. Census Bureau Urban Areas (UAs), Impervious Surface Coverage (ISC) from the 2011 National Land Cover Dataset (NLCD), and National Hydrography Dataset (NHD) flowlines, allowed the delineation of urban stream deserts (UrbSDs), or watershed areas where stream channels have likely been buried or removed. Approximately 6.2% of the area of UAs (or 11,490 km2) within the 11 Megaregions are UrbSD, and they are most prevalent in major cities in the North California and Great Lakes Megaregions. More specifically, 537 UrbSD exist within the Great Lakes Megaregion, with Detroit (MI) and Chicago (IL) comprising some of the largest UrbSDs in the United States. Regardless of Megaregion, UrbSDs represent the most intensely urbanized components of the urban environment, as UrbSDs have higher population densities, impervious surface coverage and developed land uses than adjacent urban areas. UrbSD are unique, but poorly understood, components of the urban ecosystem that highlights the consequences of sacrificing long-term environmental sustainability (e.g., ecosystem services) for short-term economic growth (rapid development).