In international water management, “virtual water” analysis has been a useful tool for discussing the flow of water resource benefits amongst nations. Conceptually, an analogy can be made with “commute shed” research — the geospatial analysis of workers and where they travel to for work, created for regional developers and labor economists. Based on the rationale that clean water supply and infrastructure “produce” healthy, able workers that can generate economic output, I argue that flows of labor are thus also flows of water supply benefits. Subsequently, workers who work outside of their water utility service area are exporting these embedded economic benefits. Commute sheds can thus represent the transfer of water supply benefits within a region.
Using OnTheMap 3, a recently developed software from the United States Census Bureau, I compile commute sheds for municipalities within and neighboring the Upper Neuse River Basin, North Carolina. I interpolate the water supply benefits embedded in these commute sheds, using estimated annual earnings as a proxy for economic output. Results show that within the Upper Neuse, there is a net flow of benefits from other cities into Durham. Also, there is a net flow of benefits into the Upper Neuse from cities supported by neighboring water systems, particularly by Jordan Lake.
To my knowledge, this is a novel demonstration of applying OnTheMap to regional water supply management and virtual water flows. OnTheMap can be used to illustrate aspects of interdependence amongst regional water users, improving decision making in water supply management efforts and help forecast future water demand by location. Complemented with benefit valuation research, commute shed analysis can inform negotiations on water transfer agreements and collaborative infrastructure financing.
Author: BEN YOUNG LANDIS*
Masters project submitted in partial fulfillment of the requirements for the Master of Environmental Management degree in the Nicholas School of the Environment of Duke University, 2009. Thesis Adviser: Randall Kramer.
Keywords: commute sheds, virtual water, regional analysis, water supply benefits, interbasin transfers, infrastructure financing, Falls Lake
Author’s Note: This website was created in October 2013, presenting the contents and findings of this masters thesis as originally published in April 2009. Since the time of publication, water management policies in the Upper Neuse River Basin have continued to evolve, and the U.S. Census Bureau has made continuous improvements to its OnTheMap software. As such, the reader should consider the findings and methodology of this thesis in its historic context. Nevertheless, it is my hope that the commute shed analysis ideas presented herein still have relevant applications, and can stimulate continued discussions in the field of watershed management theory.
*Current Affiliation: U.S. Geological Survey, Sacramento, California