In order to address these limitations, Drs. Jennifer Tank, University of Notre Dame, Michelle Baker, Utah State University, and Robert Hall, University of Wyoming, and Dr. Rosi developed a new method to measure nutrient uptake in a large river (Tank et al. 2008). These data are some of the first empirical measurements of nutrient uptake in a river and we are extending this research to include measurement of nutrient uptake in other large river ecosystems throughout the Western and Midwestern US.