Issdotv2 Methodology, Uncertainty, and Applications For Measuring Bed-Load Transport

Bed-load transport is an important process impacting riverine morphology, habitat suitability, the development of sediment budgets, flow resistance, and flood protection; however, limited measurements are available due to the difficulty in quantifying bed load on large river systems. The Integrated, Section Surface Difference Over Time, version 2 (ISSDOTv2) method provides a means of quantifying the bed load in large, sand bed rivers using high-resolution acoustic multi-beam data. The numerical code was validated using flume measurements for various flow rates for both steady and unsteady conditions. The results indicate that the accuracy of the ISSDOTv2 method was improved with higher transport rates. Additionally, the laboratory flume results were used to test a process for calculating uncertainty in the ISSDOTv2 results. While the absolute uncertainties increased for higher transport rates, uncertainties relative to the transport rate generally decreased for higher transport conditions. Application of the ISSDOTv2 methodology to measurements on the Mississippi River at Vicksburg, MS indicate ISSDOTv2 uncertainties of approximately 15 – 55%, depending on transport conditions.