USGS 08012150 Mermentau River At Mermentau, LA

PROVISIONAL DATA SUBJECT TO REVISION

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Data are tidally affected--Astronomical tides cause significant cycles of approximately 24.84 hours at this site. Because a different portion of The 24.84-hour tidal cycle is averaged in successive daily (24-hour) computations, a systematic secondary oscillation, unrelated to basin hydrology and having a period of about two weeks may be apparent in daily data published from October 1984 to September 2015.
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This station managed by the Baton Rouge Field Office.

Available Parameters Available Period
  
2000-10-01  2026-09-10
2007-10-01  2026-09-10
2023-10-01  2026-09-10
2026-08-12  2026-09-10







 (7)
 
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Summary of all available data for this site
Instantaneous-data availability statement

Discharge, cubic feet per second
Most recent instantaneous value: -233 09-10-2026   22:15 CDT
Graph of Discharge, cubic feet per second

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Daily discharge, cubic feet per second -- statistics for Sep 11 based on 24 water years of record more
Min
(1999)		 Most Recent
Instantaneous
Value Sep 11		 25th
percen-
tile		 Median Mean 75th
percen-
tile		 Max
(2001)
-704 -233 -145 449 1520 2230 14400

Gage height, feet
Most recent instantaneous value: 2.01 09-10-2026   22:15 CDT
Graph of Gage height, feet

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Stream water level elevation above NAVD 1988, in feet, [NAVD88 GEOID18]
Most recent instantaneous value: 0.72 09-10-2026   22:15 CDT
Graph of Stream water level elevation above NAVD 1988, in feet, [NAVD88 GEOID18]

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Water velocity reading from field sensor, feet per second, [XVel.RA.SL.1500]
Most recent instantaneous value: -0.05 09-10-2026   22:15 CDT
Graph of Water velocity reading from field sensor, feet per second, [XVel.RA.SL.1500]

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