Location context and information
LOCATION.-- On left bank 100 feet downstream of bridge on Riverdale Road, 1.8 mi downstream from Indian Creek, and 1.8 mi upstream from confluence with Northwest Branch. PERIOD OF RECORD.-- August 1938 to current year. GAGE.-- Water-stage recorder and crest-stage gage. Datum of gage is 11.55 ft above North American Vertical Datum of 1988. Prior to June 12, 1942, nonrecording gage; June 12, 1942 to Mar. 22, 1966, and Apr. 12, 1967 to Sept. 3, 1969, water-stage recorder, all at bridge at datum 14.00 ft above National Geodetic Vertical Datum of 1929. Mar. 23, 1966 to Apr. 11, 1967, nonrecording gage 600 ft downstream from bridge at datum 9.25 ft above National Geodetic Vertical Datum of 1929. Sept. 3, 1969 to Jan. 12, 2012, recording gage on right bank at downstream side of bridge at present gage datum. REMARKS.-- Some regulation at low flow by sand and gravel plants upstream from station. PERIOD OF DAILY RECORD (Water Quality).-- SPECIFIC CONDUCTANCE: December 2003 to December 2005, July 2006 to November 2007, March 2008 to current year. WATER TEMPERATURE: December 2003 to December 2005, July 2006 to November 2007, March 2008 to current year. pH: December 2003 to December 2005, July 2006 to November 2007, March 2008 to current year. TURBIDITY: December 2003 to December 2005, July 2006 to November 2007, March 2008 to current year. DISSOLVED OXYGEN: December 2003 to December 2005, July 2006 to November 2007, March 2008 to current year. REMARKS (Water Quality).-- Turbidity values greater than 1,000 formazin nepthelometric units (FNU) exceed the instrument calibration range. Values above 1,000 FNU are included in the record but are presumed to have lower accuracy. The accuracy limit of the turbidity sensor in low turbidity water is +/- 0.3 FNU. October 1, 2024: Values are censored and qualified as Less Than 0.3 FNU if they are recorded below 0.3 FNU. For 2016 WY (December through end of January), some specific conductivity values greater than the high-end calibration range (SC-standard solution) values were included in the record, but presume to have lower precision even though SC probe is reliable.
