Evaluation of metal loading to streams near Creede, Colorado, August and September 2000

Scientific Investigations Report 2004-5143
Prepared in cooperation with the City of Creede, Colorado and the U.S. Forest Service
By: , and 



Decisions about remediation of mine drainage on the watershed scale require an understanding of metal contributions from all sources to be able to choose the best sites for remediation. A hydrologic framework to study metal loading in the Willow Creek watershed, a tributary to the Rio Grande River, was established by conducting a series of tracer-injection studies. Each study used the tracer-dilution method in conjunction with synoptic sampling to determine the spatial distribution of discharge and concentration. Discharge and concentration data were then used to develop mass-loading curves for the metals of interest. The discharge and load profiles (1) identify the principal sources of load to the streams; (2) demonstrate the scale of unsampled, dispersed subsurface inflows; and (3) estimate the amount of natural attenuation. The greatest source of metal loads was from the Nelson Tunnel on West Willow Creek, which contributed 158 kilograms per day of zinc to the stream. Additional loading from other dispersed, subsurface inflows along West Willow Creek added substantial loads, but these were small in comparison to the loads from the Nelson Tunnel. No significant contributions of metal load from potential sources occurred along East Willow Creek. The lack of measurable loading may be a result of previous remedial actions along that stream. The lower Willow Creek section had relatively small contributions of load compared to what had been contributed upstream. This watershed approach provides a detailed snapshot of metal load for the watershed to support remediation decisions and quantifies processes that affect metal transport.

Study Area

Additional publication details

Publication type Report
Publication Subtype USGS Numbered Series
Title Evaluation of metal loading to streams near Creede, Colorado, August and September 2000
Series title Scientific Investigations Report
Series number 2004-5143
DOI 10.3133/sir20045143
Edition Online only
Year Published 2006
Language English
Publisher U.S. Geological Survey
Publisher location Salt Lake City, UT
Contributing office(s) Utah Water Science Center, Toxic Substances Hydrology Program
Description viii, 64 p.
Time Range Start 2000-08-01
Time Range End 2000-09-30
Country United States
State Colorado
City Creede
Online Only (Y/N) Y
Additional Online Files (Y/N) Y