Computing time-series suspended-sediment concentrations and loads from in-stream turbidity-sensor and streamflow data

Patrick P. Rasmussen; John R. Gray; G. Doug Glysson; Andrew C. Ziegler

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USGS · 70120689

Computing time-series suspended-sediment concentrations and loads from in-stream turbidity-sensor and streamflow data

Patrick P. Rasmussen·John R. Gray·G. Doug Glysson·Andrew C. Ziegler

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Abstract

Over the last decade, use of a method for computing suspended-sediment concentration and loads using turbidity sensors—primarily nephelometry, but also optical backscatter—has proliferated. Because an in- itu turbidity sensor is capa le of measuring turbidity instantaneously, a turbidity time series can be recorded and related directly to time-varying suspended-sediment concentrations. Depending on the suspended-sediment characteristics of the measurement site, this method can be more reliable and, in many cases, a more accurate means for computing suspended-sediment concentrations and loads than traditional U.S. Geological Survey computational methods. Guidelines and procedures for estimating time s ries of suspended-sediment concentration and loading as a function of turbidity and streamflow data have been published in a U.S. Geological Survey Techniques and Methods Report, Book 3, Chapter C4. This paper is a summary of these guidelines and discusses some of the concepts, s atistical procedures, and techniques used to maintain a multiyear suspended sediment time series.

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Patrick P. Rasmussen, John R. Gray, G. Doug Glysson, Andrew C. Ziegler. 2010. Computing time-series suspended-sediment concentrations and loads from in-stream turbidity-sensor and streamflow data. https://pubs.usgs.gov/publication/70120689

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