Land Use Change in NW Arkansas: Implications for Runoff Potential on the West Fork Watershed

Northwest Arkansas is rated as one of the top 10 fastest growing metropolitan areas in the U.S. This urban growth has resulted in a rapid change in land use/land cover patterns over the last 30 years. Land use/land cover in turn affects weather patterns, extreme weather events, rainfall runoff and water quality. This paper evaluates the changes in land use patterns in the Northwest Arkansas region for the period 1977 through 2006. Five Landsat images were classified into 5 land use types. The traditional soil conservation service-curve number (SCS-CN) method of determining runoff was applied to the 321 km² watershed of the West Fork of White River in Northwest Arkansas to evaluate the landscape´s runoff generating potential. Maps of distributed runoff generation potential were developed in a geographic information system (GIS) environment from the runoff model for each year of study. Overall classification accuracy ranged between 85% and 97% with Kappa coefficients between 0.78 and 0.95. Results indicate a linear increase in runoff generating areas coming from urban and grassed areas. This study has direct implications on water quality and quantity and the methods could be adopted as a tool for land management.