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USGS 01654500 LONG BRANCH NEAR ANNANDALE, VA

PROVISIONAL DATA SUBJECT TO REVISION

Click to hidestation-specific text
Station operated in cooperation with Fairfax County, Virginia

Gage is being relocated. During this transition period, discharge data is only partially available. We are working to get discharge back online as soon as possible. We appreciate your patience during this time.
NOTE: During storm events, backwater effects on stage and discharge determinations at this station are likely. Streamflow data displayed on this page may be significantly different from actual values during these events. Adjustment of data for backwater effects can only be done after detailed analysis. Users are encouraged to contact this office for more information.
This station managed by the Richmond Field Office.

Available Parameters Available Period
  
2013-02-08  2026-07-17
2013-02-08  2026-07-17
2013-02-07  2026-07-17
2013-02-08  2026-07-17
2013-02-08  2026-07-17
2013-02-08  2026-07-17
2013-02-08  2017-08-31
2017-08-31  2026-07-17
2026-03-19  2026-07-17







 (7)
 
  -- or --

 

 
Summary of all available data for this site
Instantaneous-data availability statement

Temperature, water, degrees Celsius
Most recent instantaneous value: 27.3 07-17-2026   13:45 EDT
Graph of Temperature, water, degrees Celsius

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Discharge, cubic feet per second
Most recent instantaneous value: 0.38 07-17-2026   13:55 EDT
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Daily discharge, cubic feet per second -- statistics for Jul 17 based on 22 water years of record more
Min
(2017)		 Most Recent
Instantaneous
Value Jul 17		 25th
percen-
tile		 Median 75th
percen-
tile		 Mean Max
(2018)
0.23 0.38 0.63 1.5 2.1 4.8 41.3

Gage height, feet
Most recent instantaneous value: 2.43 07-17-2026   13:55 EDT
Graph of Gage height, feet

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Specific conductance, water, unfiltered, microsiemens per centimeter at 25 degrees Celsius
Most recent instantaneous value: 237 07-17-2026   13:45 EDT
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Dissolved oxygen, water, unfiltered, milligrams per liter
Most recent instantaneous value: 12.0 07-17-2026   13:45 EDT
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pH, water, unfiltered, field, standard units
Most recent instantaneous value: 8.2 07-17-2026   13:45 EDT
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Turbidity, water, unfiltered, monochrome near infra-red LED light, 780-900 nm, detection angle 90 +-2.5 degrees, formazin nephelometric units (FNU), [YSI 6136]
 
-- Data temporarily unavailable for the time period specified --

Turbidity, water, unfiltered, monochrome near infra-red LED light, 780-900 nm, detection angle 90 +-2.5 degrees, formazin nephelometric units (FNU), [YSI EXO]
Most recent instantaneous value: 0.6 07-17-2026   13:45 EDT
Graph of Turbidity, water, unfiltered, monochrome near infra-red LED light, 780-900 nm, detection angle 90 +-2.5 degrees, formazin nephelometric units (FNU), [YSI EXO]

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Count of samples collected by autosampler, number
Most recent instantaneous value: 0 07-17-2026   13:45 EDT
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