How do urban drinking water supply reservoirs shift local demographics?Michael Youth (mdyouth@ncsu.edu), George Hess, Melissa McHale, M. Nils Peterson

North Carolina State University – Department of Forestry and Environmental Resources

Infrastructure designed to improve urban sustainability can induce four basic processes that raise environmental justice concerns:

Background

HypothesisBuilding a dam to create an urban drinking water supply reservoir in North Carolina, USA, tends to initiate a gentrification process in the community neighboring the new reservoir.

Results

Acknowledgments

• Triangle Urban Long-Term Research Area (ULTRA) (http://www.triangleultra.org)

• National Science Foundation (Award No. 0948229) • Minnesota Population Center (http://www.nhgis.org)• ncONEmap (http://www.nconemap.com) • NCSU Libraries Geospatial (GIS) Data Services • NCSU Urban Ecology Labgroup• Danielle Spurlock and Ben Coakley

•Boom-and-bust hydrological cycles predicted in association with climate change may prompt the building of additional urban drinking water supply reservoirs.

•Our results are consistent with the hypothesis that North Carolina urban drinking water supply reservoirs generally induce race and income gentrification.

•Further research is needed to (1) extend the temporal analysis and (2) determine whether the observed inequality generally reflects inequity or something else, such as cultural preferences.

Methods• 66 urban drinking water supply reservoirs

in North Carolina, USA (maps to right)

• 1990 and 2000 high-resolution U.S. Census data, re-aggregated to four “buffers” around the reservoirs: 0-0.5 mi, 0.5-1 mi, 1-3 mi, and 3-5 mi

• ANOVAs (α = .05) comparing mean white population (%) and mean per capita income for each buffer and for the county the reservoir sits in (bar graphs to right)

• T-tests (α = .05) comparing standardized 1990 and 2000 buffer means

Different letters atop bars = significant difference (α = .05)

• The communities in the 0-0.5 mi lakeside buffers have a significantly higher proportion of white people than (1) the communities living in the 1-3 mi and 3-5 mi buffers and (2) the counties in which they sit.

• The proportion of white people in the 0-0.5 mi lakeside community increased significantly between 1990 and 2000 (after standardizing the mean percentages white to the overall state percentages).

Different letters atop bars = significant difference (α = .05)

• By 2000, the communities in the 0-0.5 mi lakeside buffers tend to have a higher per capita income than (1) the communities living in the 1-3 mi and 3-5 mi buffers and (2) the counties in which they sit.

• Though per capita income increased significantly in all buffers between 1990 and 2000, the largest absolute mean increase occurred in the 0-0.5 mi lakeside community.

White Population (%) Per Capita Income

Conclusions

•The community within ½ mile of urban drinking water supply reservoirs tends to have (1) a higher proportion of white people and (2) higher per capita income than more distant communities.•Temporally, the data are consistent with race and income gentrification.

White Population in 2000 (%) Per Capita Income in 2000 (Year 2000 $)