Water Resources Research Act Program

Details for Project ID 2015VT77B

System-wide quantification of streambank erosion

Institute: Vermont
Year Established: 2015 Start Date: 2015-03-01 End Date: 2016-02-28
Total Federal Funds: $38,542 Total Non-Federal Funds: $78,673

Principal Investigators: Mandar Dewoolkar, Jarlath ONeilDunne, Donna Rizzo, Jeff frolik

Project Summary: Rill erosion from farmland and streambank erosion are common non-point sources contributing to suspended sediment and pollution into streams and waterways. Streambank erosion is estimated to account for 30-80% of sediment loading into lakes and waterways. Langendoen et al. (2012) recently conducted a study involving extensive fieldwork and BSTEM (Bank Stability and Toe Erosion Model) modeling for the State of Vermont to estimate sediment loadings from streambank erosion in main stem reaches of Missisquoi River. Using the flow records between 1979 and 2010, they predicted that 36% of the total suspended-sediment load entering Missisquoi Bay (31,600 t/yr) was derived from streambank erosion. These estimates were based on “one-time”, yet labor and resource intensive, field work conducted at 27 sites that were extrapolated to 110 km of stream length and across 30 years in time. Although this study demonstrated that the estimates of streambank erosion can be obtained at the watershed level, this approach requires tremendous resources. Recent approaches such as aerial LiDAR have proved effective for watershed level assessment, but airborne LiDAR data collection is costly. Terrestrial LiDAR is more affordable if the equipment is available, but the equipment is bulky (especially for reaching remote locations) and data collection is time consuming and limited to relatively small areas. Therefore, cost-effective approaches to reliably quantify streambank erosion at the watershed level have remained an elusive goal for the stream geomorphology community. Recent developments in Unmanned Aerial Systems (UAS) provide opportunities for rapidly and economically determining streambank erosion and deposition at variable scales (from site specific to watershed scale). The objectives of the proposed study are to: (1) develop decision support tools to effectively acquire and process continuous streambank profiles using an affordable UAS fitted with appropriate camera; (2) compare the results at select sites from terrestrial and airborne LiDAR-based surveys; (3) develop and validate a methodology to reliably quantify annual system-level streambank erosion and deposition rates; and (4) develop and incorporate related educational modules for The University of Vermont (UVM) coursework and conduct professional development workshops for Vermont state and government personnel. The project capitalizes on significant expertise that have been developed at UVM in UAS and terrestrial LiDAR technologies, and current field campaigns conducted in the Mad River Watershed, which has been proposed as the study site. The Mad River Watershed experienced substantial damage during Tropical Storm Irene and also has been one of the major subjects of study during the current NSF EPSCoR RACC project. This study area is scheduled to be covered by airborne LiDAR in 2015. The educational component of this project includes graduate and undergraduate researchers and the incorporation of research methods and results of this project into PIs’ courses and professional development workshops developed and conducted for Vermont state and government personnel. This work should have substantial impact on the understanding of bank stability and sediment input to Vermont streams. In particular, we will be able to provide a field-validated methodology that will allow reliable quantification of the contribution of streambanks to sediment loadings in waterways, using Vermont as the case study. In many cases, this sediment is carrying important pollutants, such as phosphorus. The developed methodology will be cost-effective for measuring rate and quantity of streambank erosion and transferrable to other regions in and outside of Vermont.