Calibration of streamflow gauging stations at the Tenderfoot Creek Experimental Forest

Abstract

We used tracer based methods to calibrate eleven streamflow gauging stations at the Tenderfoot Creek Experimental Forest in western Montana. At six of the stations the measured flows were consistent with the existing rating curves. At Lower and Upper Stringer Creek, Upper Sun Creek and Upper Tenderfoot Creek the published flows, based on the existing rating curves, were higher than the actual flows, while at Lower Sun Creek the published flows were lower than the actual flows. At the Lower and Upper Stringer Creek and Upper Tenderfoot Creek sites we recommend that the flumes be examined for evidence of the cause of the inaccurate measurements and that appropriate remedial action be taken. Specific points include 1) verifying that the flume geometly is correct, that the flume is straight and horizontal, and that the flume has not been damaged; 2) clearing debris from within or around the flume; and 3) comparing electronically recorded stage values to those observed on the flume staff plate. In the event that there is no evidence of the cause of the observed measurement discrepancy we recommend additional measurements at these flumes to verify the measurements already obtained and to develop new rating curves. At the Upper Sun Creek we recommend that additional measurements be taken across a wider range of flows so that a new rating curve can be developed. At Lower Sun Creek we recommend that the flume installation be checked for leaks and appropriate remedial action taken.

Citation

Woods, Scott W. 2007. Calibration of streamflow gauging stations at the Tenderfoot Creek Experimental Forest. Final Technical Report 02-JV-11222022-183. Missoula, MT: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. 37 p.