Beyond imperviousness- Investigating the influence of urban form and socioeconomic characteristics on urban stream water quality in the Continental United States
Abstract
Urban development impairs 30,000 miles (13%) of streams in the United States, resulting in higher water temperature, lower dissolved oxygen, increased sedimentation, and enhanced level of nutrients, metals, bacteria, and other constituents. Current research investigating the impact of urban development on stream water quality relies on the fundamental relationship between the amount of imperviousness and pollutant generation, transportation processes. For example, it was found that the total impervious cover of an urban watershed causes stream degradation at the threshold of 10% to 15%. However, given the similar impervious percentages, urban landscapes still have high variations in their spatial pattern (location and geometry of impervious area), development intensity, and neighborhood demographic characteristics. Here, we conducted the first continental-scale urban stream water quality study with a comprehensive social-ecological framework to investigate (1) the social inequities with respect to stream water contamination exposure; (2) the characteristics of the built environment (e.g. building footprint, street length, land use spatial pattern) associated with urban stream water quality; and (3) the spatial variations of how urban form and socioeconomic drivers influence urban stream water quality, particularly the variations in different climate regions. We compiled a continental-scale dataset to document various urban form and socioeconomic drivers of urban stream water quality degradation by integrating remotely sensed data, census tract data, and other open-sources data with pollutant indicators of total suspended solid, total phosphorus, and total nitrogen derived from U.S. Water Quality Portal. With Bayesian hierarchical model, we found that the category (e.g. different types of streets), location (e.g. urban development on different types of soils and topography), and the configuration (e.g. sprawl versus compact development) of impervious area all have strong associations with stream water quality after controlling for the impervious surface percentage. Moreover, watersheds with more rented houses and lower household income have a higher TSS concentration, implying a potential environmental justice issue. We expect the outcome of this research can help us learn more about underlying social mechanisms of urban stream water quality degradation and suggest urban planning and regional development policy to remedy the degradation.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2022
- Bibcode:
- 2022AGUFM.H12G..02W