Comparison of sediment transport formulas and computation of sediment discharges for the North Fork Toutle and Toutle rivers, near Mount St. Helens, Washington

This preliminary report presents results of computations using twelve different sediment discharge formulas along with data from two data collection sites in the Toutle River basin. Output from six bed material discharge formulas and six bedload discharge formulas was considered. The results of the computations are presented graphically for comparison purposes only. In addition to output from the formulas, the results from suspended-sediment samples and several bedload measurements using a Helley-Smith type bedload sampler are presented. No interpretation of the output is provided. (USGS)