Datums for 8775131, Portland


NOTICE: All data values are relative to the MLLW.

Elevations on Mean Lower Low Water

Station: 8775131, Portland
Status: Accepted (Apr 19 2021)
Units: Feet
Control Station: 8775296 USS Lexington, Corpus Christi Bay, TX
T.M.: 0
Epoch: 2002-2006
Datum: MLLW
DatumValueDescription
MHHW0.62Mean Higher-High Water
MHW0.60Mean High Water
MTL0.30Mean Tide Level
MSL0.36Mean Sea Level
DTL0.31Mean Diurnal Tide Level
MLW0.02Mean Low Water
MLLW0.00Mean Lower-Low Water
NAVD88-0.39North American Vertical Datum of 1988
STND-30.88Station Datum
GT0.61Great Diurnal Range
MN0.58Mean Range of Tide
DHQ0.02Mean Diurnal High Water Inequality
DLQ0.01Mean Diurnal Low Water Inequality
HWIGreenwich High Water Interval (in hours)
LWIGreenwich Low Water Interval (in hours)
Max TideHighest Observed Tide
Max Tide Date & Time Highest Observed Tide Date & Time
Min TideLowest Observed Tide
Min Tide Date & Time Lowest Observed Tide Date & Time
HAT0.93Highest Astronomical Tide
HAT Date & Time12/06/2025 08:00HAT Date and Time
LAT-0.37Lowest Astronomical Tide
LAT Date & Time12/05/2025 20:00LAT Date and Time
Tidal Datum Analysis Periods
01/01/2020 - 05/31/2020




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