Intake efficiency field results for Federal Interagency Sedimentation Project bag samplers

First posted July 20, 2022 For additional information, contact: Director, Central Midwest Water Science CenterU.S. Geological Survey405 North Goodwin Ave.Urbana, IL 61801 The Federal Interagency Sedimentation Project (FISP) standardizes and advances sediment science among federal agencies. It is important to ensure that the FISP bag samplers perform isokinetically under all tested approved conditions collect samples are representative of stream or river cross-section. A measure a sampler’s isokinetic behavior its intake efficiency, which defined as ratio velocity through nozzle entrance sampler ambient velocity. efficiencies sizes were evaluated for this report. Samples obtained across 31 U.S. Survey streamflow-gaging stations between 15, 2013, June 17, 2020, where data collected with four (US D-96, D-96-A1, D-99, DH-2), each using various 3/16-inch, 1/4-inch, 5/16-inch diameter nozzles.Water temperature outside two several factors known affect efficiency samplers. regression curve was fitted these LOWESS (locally weighted scatterplot smoothing), Kruskal-Wallis test executed sizes. Based on results, there no statistical evidence indicate water have noticeable effect when deployed conditions. Likewise, type direct efficiency.