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USGS 01646000 DIFFICULT RUN NEAR GREAT FALLS, VA

  Stream Site

DESCRIPTION:
Latitude 38°58'33",   Longitude 77°14'46"   NAD27
Fairfax County, Virginia, Hydrologic Unit 02070008
Drainage area: 57.8 square miles
Datum of gage: 150.94 feet above   NAVD88.
AVAILABLE DATA:
Data Type Begin Date End Date Count
 Current / Historical Observations     (availability statement)    2007-10-01  2016-09-28  
 Daily Data
    Temperature, water, degrees Celsius  2006-09-22  2016-09-26  8616 
    Discharge, cubic feet per second  1935-04-01  2016-09-26  29765 
    Specific conductance, water, unfiltered, microsiemens per centimeter at 25 degrees Celsius  2006-10-01  2016-09-26  8464 
    Dissolved oxygen, water, unfiltered, milligrams per liter  2012-10-11  2016-09-26  5468 
    pH, water, unfiltered, field, standard units  2012-10-11  2016-09-26  4212 
    Turbidity, water, unfiltered, monochrome near infra-red LED light, 780-900 nm, detection angle 90 +-2.5 degrees, formazin nephelometric units (FNU)  2012-10-12  2016-09-26  5124 
    Nitrate plus nitrite, water, in situ, milligrams per liter as nitrogen  2012-10-19  2016-09-26  3819 
 Daily Statistics 
    Temperature, water, degrees Celsius  2006-09-22  2015-10-25 1821 
    Discharge, cubic feet per second  1935-04-01  2016-04-25 29611 
    Specific conductance, water, unfiltered, microsiemens per centimeter at 25 degrees Celsius  2006-10-01  2015-10-25 1796 
    Dissolved oxygen, water, unfiltered, milligrams per liter  2012-10-11  2015-10-25 1034 
    Turbidity, water, unfiltered, monochrome near infra-red LED light, 780-900 nm, detection angle 90 +-2.5 degrees, formazin nephelometric units (FNU)  2012-10-12  2015-10-25 979 
 Monthly Statistics 
    Temperature, water, degrees Celsius  2006-09  2015-10  
    Discharge, cubic feet per second  1935-04  2016-04  
    Specific conductance, water, unfiltered, microsiemens per centimeter at 25 degrees Celsius  2006-10  2015-10  
    Dissolved oxygen, water, unfiltered, milligrams per liter  2012-10  2015-10  
    Turbidity, water, unfiltered, monochrome near infra-red LED light, 780-900 nm, detection angle 90 +-2.5 degrees, formazin nephelometric units (FNU)  2012-10  2015-10  
 Annual Statistics 
    Temperature, water, degrees Celsius  2006  2016  
    Discharge, cubic feet per second  1935  2016  
    Specific conductance, water, unfiltered, microsiemens per centimeter at 25 degrees Celsius  2007  2016  
    Dissolved oxygen, water, unfiltered, milligrams per liter  2013  2016  
    Turbidity, water, unfiltered, monochrome near infra-red LED light, 780-900 nm, detection angle 90 +-2.5 degrees, formazin nephelometric units (FNU)  2013  2016  
 Peak streamflow 1935-09-06  2015-07-09  81 
 Field measurements 1935-02-12  2016-09-22  746 
 Field/Lab water-quality samples 1945-04-03  2016-09-14  161 
 Water-Year Summary 2006  2015  10 

Additional Data Sources

Begin Date

End Date

Count
 Instantaneous-Data Archive  **offsite** 1990-10-01  2007-09-30  334800 
OPERATION:
Record for this site is maintained by the USGS Virginia Water Science Center
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