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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.
National Weather Service forecast for this station
National Weather Service station , and basin wide forcast.
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> Rating Information
This station managed by the Baton Rouge Field Office.

Available Parameters Available Period
  
2000-10-01  2026-04-26
2007-10-01  2026-08-04
2023-10-01  2026-08-04
2026-04-06  2026-04-26







 (7)
 
  -- or --

 

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

Discharge, cubic feet per second
Most recent instantaneous value: *** 04-26-2026   15:30 CDT
Graph of Discharge, cubic feet per second

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Daily discharge, cubic feet per second -- statistics for Aug 4 based on 21 water years of record more
Min
(1999)		 25th
percen-
tile		 Most Recent
Instantaneous
Value Aug 4		 Median Mean 75th
percen-
tile		 Max
(2014)
-1130 -111 -- unavailable -- 410 498 972 2410

Gage height, feet
Most recent instantaneous value: 2.28 08-04-2026   19:15 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: 0.99 08-04-2026   19:15 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]
 
-- Data temporarily unavailable for the time period specified --