USGS Water-Year Summary 2024
12323720 WILLOW CREEK AT OPPORTUNITY, MT
LOCATION - Lat 46°06'25.79", long 112°48'38.20" referenced to North American Datum of 1983, in NW 1/4 NE 1/4 NW 1/4 sec.14, T.4 N., R.10 W., Deer Lodge County, MT, Hydrologic Unit 17010201, 1,300 ft upstream from Stuart Street culverts, at Opportunity, 1.2 mi upstream from Mill-Willow Bypass, and at river mile 1.2.
DRAINAGE AREA - 28.6 mi².
REVISIONS HISTORY - WDR MT-2013: Drainage area.
SURFACE-WATER RECORDS
PERIOD OF RECORD - April 2003 to current year.
GAGE - Water-stage recorder. Elevation of gage is 4,930 ft, referenced to the North American Vertical Datum of 1988.
WATER-QUALITY RECORDS
PERIOD OF RECORD - March 2003 to current year.
PERIOD OF DAILY RECORD - TURBIDITY: April 2013 to current year (seasonal record).
INSTRUMENTATION - Turbidity monitor was installed in April 2013.
EXTREMES FOR PERIOD OF DAILY RECORD - TURBIDITY (seasonal record): Maximum, 190 formazin nephelometric units (FNU), May 27, 2013;
minimum, 1.0 FNU, Aug. 20-21, and 23, 2013.
EXTREMES FOR CURRENT YEAR - TURBIDITY: During period of seasonal operation, maximum, 32.6 formazin nephelometric units June 11, 2019, minimum 0.5 FNU many days from July through September 2019.