Twenty years of conservation effects assessment in the St. Joseph River watershed, Indiana

Lake Erie has a long and storied history with water quality impairment and conservation. Following the passing of the Clean Water Act in the 1970s, total phosphorus (P) loading to the lake substantially decreased through permitting of point sources and through conservation efforts to decrease sediment loss from agricultural fields. While total P losses to Lake Erie have remained relatively stable since the 1990s, dissolved P has increased and resulted in increases in the extent and severity of algal blooms over the past two decades (Smith et al. 2015b). Both agricultural industry and environmental quality are vital to local and regional economies. To achieve a balance between these important resources, there is a critical need to better understand the effect of agricultural practices on crop production and water quality in the national priority Lake Erie watershed.