This report reviews how nitrogen and phosphorus, especially the refractory compounds, are defined in the input, interactions, and output of water quality models and to provide recommendations for model updates. It highlights the need to understand nutrient speciation and refractory compounds and why it is important to use this information in water quality modeling to improve water quality simulations to provide the most accurate portrayal of current and future conditions when nutrient management activities are undertaken. Published by WE&RF. 108 pages. Online PDF. (2016)
Originally funded as WERF project NUTR1R06aa.