Field techniques for suspended-sediment measurement

The measurement of suspended sediment, particularly in field settings, is important in the documentation of sediment transport and deposition. Many measurement techniques have been used with varying degrees of success. The techniques, including their operating principles, advantages, and disadvantages are discussed. The techniques discussed include acoustic, bottle, pump, focused beam reflectance, laser diffraction, nuclear, optical backscatter, optical transmission, and spectral reflectance. Emphasis is placed on instrumentation techniques, as this is the area of suspended-sediment measurement that has the greatest potential for improving sediment data. Acoustic technology (if further developed) emerges as a promising technology because of its ability to measure the concentration profile without intruding into the flow. This technology-transfer information will be valuable to practitioners and researchers needing to choose a means of measuring suspended sediment. The choice of a measurement technique has implications for sampling efficacy and expense.