Suspended sediment concentration and loads for the Nooksack River at Ferndale, Washington, 2012-2017 water years

Turbidity was continuously monitored at the USGS streamgage Nooksack River at Ferndale (12213100) from October 29, 2011 to September 30, 2017. A DTS-12 turbidity sensor (Forest Technology Systems) at the streamgage measured turbidity at 15-minute intervals. Suspended-sediment samples were collected at the streamgage over a range of discharge and turbidity conditions. Regression equations were developed to estimate the suspended-sediment concentration (SSC) and the concentration of fine suspended-sediment (fSSC; <0.0625 mm) using turbidity as an explanatory variable. A 15-minute time series of SSC, fSSC, and the uncertainty of individual estimates (prediction intervals with 90 percent confidence) was computed and is provided. A daily time series of suspended-sediment load (SSL) and fine suspended-sediment load (fSSL), derived from either 15-minute or daily SSC and discharge data, was computed for the 2012-2017 water years.