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USGS 14203500 TUALATIN RIVER NEAR DILLEY, OR

PROVISIONAL DATA SUBJECT TO REVISION

Click to hidestation-specific text

Station operated in cooperation with the Bureau of Reclamation and the U.S. Army Corps of Engineers.

NOTE: River forecasts and additional data can be obtained at the 
National Weather Service's Advanced Hydrologic Prediction Services web page.

NOTE: The most current shifted rating for this site can be found at USGS Rating Depot website.
Available Parameters Available Period
  
2016-03-26  2026-05-31
1986-10-01  2026-05-31
2007-10-01  2026-05-31
2016-03-26  2026-05-31
2020-02-19  2026-05-31
2016-03-26  2026-05-31
2023-05-31  2026-05-31
2023-10-17  2026-05-31
2023-10-17  2026-05-31
2016-03-26  2026-05-31







 (7)
 
  -- or --

 

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

Temperature, water, degrees Celsius
Most recent instantaneous value: 11.6 05-31-2026   04:30 PDT
Graph of Temperature, water, degrees Celsius

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Discharge, cubic feet per second
Most recent instantaneous value: 105 05-31-2026   05:10 PDT
Graph of Discharge, cubic feet per second

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Daily discharge, cubic feet per second -- statistics for May 31 based on 86 water years of record more
Min
(1966)		 25th
percen-
tile		 Most Recent
Instantaneous
Value May 31		 Median Mean 75th
percen-
tile		 Max
(1960)
55.0 87 105 112 124 143 302

Gage height, feet
Most recent instantaneous value: 10.15 05-31-2026   05:10 PDT
Graph of Gage height, feet

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Specific conductance, water, unfiltered, microsiemens per centimeter at 25 degrees Celsius
Most recent instantaneous value: 73 05-31-2026   04:30 PDT
Graph of Specific conductance, water, unfiltered, microsiemens per centimeter at 25 degrees Celsius

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Dissolved oxygen, water, unfiltered, milligrams per liter
Most recent instantaneous value: 10.4 05-31-2026   04:30 PDT
Graph of Dissolved oxygen, water, unfiltered, milligrams per liter

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pH, water, unfiltered, field, standard units
Most recent instantaneous value: 7.4 05-31-2026   04:30 PDT
Graph of pH, water, unfiltered, field, standard units

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Dissolved organic matter fluorescence (fDOM), water, in situ, concentration estimated from reference material, micrograms per liter as quinine sulfate equivalents (QSE)
Most recent instantaneous value: 12.2 05-31-2026   04:30 PDT
Graph of Dissolved organic matter fluorescence (fDOM), water, in situ, concentration estimated from reference material, micrograms per liter as quinine sulfate equivalents (QSE)

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Chlorophyll relative fluorescence (fChl), water, in situ, relative fluorescence units (RFU)
Most recent instantaneous value: 0.07 05-31-2026   04:30 PDT
Graph of Chlorophyll relative fluorescence (fChl), water, in situ, relative fluorescence units (RFU)

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Phycocyanin relative fluorescence (fPC), water, in situ, relative fluorescence units (RFU)
Most recent instantaneous value: 0.34 05-31-2026   04:30 PDT
Graph of Phycocyanin relative fluorescence (fPC), water, in situ, relative fluorescence units (RFU)

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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)
Most recent instantaneous value: 5.5 05-31-2026   04:30 PDT
Graph of Turbidity, water, unfiltered, monochrome near infra-red LED light, 780-900 nm, detection angle 90 +-2.5 degrees, formazin nephelometric units (FNU)

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