Water Resources Research Act Program

Details for Project ID 2011VT58B

Use of Acoustic Doppler Current Profiler data to estimate sediment and total phosphorus loads to Lake Champlain from the Rock River

Institute: Vermont
Year Established: 2011 Start Date: 2011-03-01 End Date: 2012-02-28
Total Federal Funds: $20,988 Total Non-Federal Funds: $30,251

Principal Investigators: Breck Bowden, James Shanley

Abstract: Reduction of phosphorus loading to Lake Champlain is a major management objective for the state of Vermont, so monitoring phosphorus transport to the lake is an essential task. For nearly twenty years this task has been accomplished by standard methods to estimate solute loads, based on manual sampling at discrete and relatively infrequent intervals. Most of the phosphorus is transported on sediments and so suspended sediment concentrations (SSC) are an excellent surrogate of total phosphorus transport. SSC can be measured relatively easily and continuously with acoustic Doppler current profilers (ADCPs). This presents the opportunity to measure a surrogate of total phosphorus concentration at a finer scale of temporal resolution than has ever been practicable before. The objective of this project is to calibrate a new ADCP that has recently been installed on the Rock River near Highgate, Vermont to estimate SSC. The instrument was installed primarily to measure discharge, but the data can be used for the purposes of this project if calibrated against manual SSC measurements. Once calibrated, we can use the ADCP data to explore the dynamics of sediment and total phosphorus transport at scales ranging from individual events to seasonal and interannual. At the very least this project will provide data that will help the Vermont Department of Environmental Conservation (VTDEC) decide if the ADCP provides a viable alternative to the current manual sampling program for sediment and total phosphorus. More importantly, the continuous record provided by the ADCP will quantify whether the current intermittent sampling program significantly biases estimates of total phosphorus loading.