Time of Travel of Soluble Contaminants in Streams

Abstract

Time of travel is measured in streams by introducing Rhodamine B dye and detecting its concentration at a downstream cross section by use of a fluorometer. The computation of the necessary dosage, the methods of dosing, the selection of the sampling points, and the methods of sampling are described. Examples and results from time of travel runs on several streams are presented. Runs have been made on reaches as long as 138 miles and for discharge less than 10 cfs to discharges over 17,000 cfs. Velocities have ranged from over 10 fps to less than 0.2 fps. The technique is promising for the study of dispersion in natural streams.