This research proposed to develop a framework that will integrate hydrologic, ecosystem, and economic analysis to quantify nonuse values of water quality improvements in the Upper Sangamon River Watershed (USRW) (Figure 2). The research design presented in this study will evaluate the hydrologic response of the watershed using integrated physically-based watershed (MIKE-SHE) and river (MIKE-11) models. The integrated models were used to simulate flow, sediment, and nutrient movements across the watershed due to different water quality improvement scenarios. Sediment load and nutrient concentration were used as measures of water clarity and nutrient reduction, respectively. Downscaled climate projections were assembled for USRW and were used to determine the response of the watershed to different water quality improvements under changing the climate. Flow characteristics (e.g., minimum flow, maximum flow, average flow, coefficient of variation, sediment load, and nutrient concentration) from the integrated models of the different water quality improvements were then correlated with the number of fish species (i.e., richness) at different sampling sites across the watershed to derive the contemporary relationship between flow characteristics and fish species richness.  A choice experiment survey of people living in and near the watershed was carried out to estimate the benefits that the improvements convey to society.

Figure 2. Components of the integrated modeling framework to quantify non-market values of watershed management projects in the Upper Sangamon River Watershed.