Integrated Watershed Economic Model for Non-Point Source Pollution Management in the Upper Big Walnut Creek Watershed, OH

Abstract

Today, non-point source pollution (NPS) is one of the major sources of water quality impairments globally (UNEP, 2007). In the US, nutrient pollution is the leading cause of water quality issues in lakes, streams, and estuaries (USEPA, 2002). Nutrient enrichment in an ecosystem would seriously degrade the integrity of that ecosystem and impair the variety of services provided by the ecosystem (Carpenter et al., 1998). In recognition of the value of ecosystem services, the United States Environmental Protection Agency (USEPA) mandates individual states to implement the Total Maximum Daily Load to limit the off-land loading of nutrients (USEPA, 2002). Additionally, federal and state governments are working on expanding the use of conservation management practices in agricultural lands to reduce the pollution load from agriculture (Ice, 2004; Mausbach and Dedrick, 2004). The cost of expansion of conservation management in agriculture has to come from the society. In addition, farmers have to bear the opportunity cost of allocation of land for conservation management. Thus, economic efficiency criteria need to be applied to prioritize conservation choices. In this context, economic efficiency would imply the combination of crop mix and conservation practices that would equalize the marginal social costs and benefits of conservation management expansion. Hence, information about economic efficiency of conservation practices are important in NPS policy making, so that planners, conservation experts and local watershed groups can prioritize conservation program in their watershed and show the worthiness of expansion of conservation management. However, the ever-increasing water quality impairment by