HR: 15:25h
AN: B32C-07    [PDF]
TI: Forest Disturbance Through Alpine Ski Area Development: Results of a Paired Watershed Study in the Northeastern U.S.
AU: * Wemple, B
EM: bwemple@zoo.uvm.edu
AF: Dept. of Geography, Univ. of Vermont, 202 Old Mill, Burlington, VT 05401
AU: Shanley, J
EM: jshanley@usgs.gov
AF: U.S. Geological Survey, P.O. Box 628, Montpelier, VT 05602
AU: Waichler, S
EM: scott.waichler@pnl.gov
AF: Pacific Northwest National Laboratory, P.O. Box 999, MSIN: K9-36, Richland, WA 99352
AB: Disturbance to forested watersheds through suburbanization and resort development is increasingly common, particularly in densely populated regions. We are examining the effects of ski resort development on flow dynamics and water quality through a paired watershed study in northern Vermont. Our watersheds include the West Branch basin (11.7 km2), which encompasses an alpine ski resort, and the Ranch Brook basin (9.6 km2), which serves as our undeveloped control. Our analysis includes empirical interpretation of three years of streamflow and water quality data, as well as model simulations of flow dynamics under current and proposed future conditions, including proposed development of expanded snowmaking, ski trails and slope side village amenities in the West Branch basin. Our results show distinct differences in hydrologic response between the two watersheds, including elevated streamflows and delayed peaks during snowmelt in the developed watershed that may be attributable to trail clearing and snowmaking. Water quality data suggest that runoff from parking lots and other disturbed surfaces result in higher suspended sediment concentrations in the developed West Branch, particularly during the early part of snowmelt and during intense summer rains. Salting of parking lots and roadways within the West Branch basin resulted in elevated chloride concentrations year round (up to 700 ueq L-1 during snowmelt). Nitrate peaked near 70 ueq L-1 in both basins during snowmelt, but generally remained somewhat higher at West Branch. Otherwise, stream chemistry at both sites was dominated by weathering solutes (Ca, Mg, Si). We argue that disturbance to forested watersheds through this form of development may be more persistent than disturbance associated with traditional forest management activities (e.g. forest harvesting) and suggest that the results of our study may provide improved insight into the effects of new forms of human disturbance in the alpine environment.
DE: 1803 Anthropogenic effects
DE: 1806 Chemistry of fresh water
DE: 1815 Erosion and sedimentation
DE: 1860 Runoff and streamflow
DE: 1871 Surface water quality
SC: Biogeosciences [B]
MN: 2003 Fall Meeting