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The Total Maximum Daily Load (TMDL) study for Pineview Reservoir was completed in 2002 and has been accepted. As is often the case, the data used in the TMDL analysis was sparse. Concerns over the accuracy and implementation of the TMDL led the Utah Water Research Laboratory and the Weber Basin Water Conservancy District to collaborate on a study of the reservoir starting in October 2007. The objective of the research work was to expand the information available about the sources of nitrogen and phosphorus to Pineview Reservoir and to improve the description accuracy of nutrient transport through the watershed. Preliminary findings were: 1) Thermal stratification occurred to varying degrees depending on location within the reservoir; 2) Nutrient concentrations responded to anoxic conditions and water column turnover; 3) Turnover and nutrient integration appeared to be related to both draw-off of the hypolimnion and wind-mixing under near-isothermal conditions; and 4) Nutrient availability varied throughout the reservoir due to differences in water column depth and loading sources. These findings led to a detailed study of watershed processes influencing nutrient transport. Nutrient transport through surface and ground water has been estimated. Grab sampling and high frequency monitoring of both ground water and surface water are being conducted. Surface and ground water flows, turbidity, ortho and total phosphorus, ammonium and nitrate nitrogen, dissolved organic nitrogen and dissolved iron are being measured. Nutrient loading to the reservoir exceeds the reservoirs TMDL study estimates.