NOTICE: CO-OPS recently determined that water level data from Anchorage, AK (9455920) contained an error due to the inclusion of erroneous water density data. This error resulted in water level measurements several centimeters lower than actual, and impacted data products from May 1, 2018 to November 30, 2024. Water level products from December 1, 2024 to present, including real-time data, are correct. We are currently working on correcting the historical water level data and downstream products. We will provide a notification once the historical data products have been updated. Any data products downloaded from this time will need to be re-downloaded. If you have any questions, please send an email to tide.predictions.gov and we will get back to you as soon as possible.

Datums for 9455920, Anchorage AK

NOTICE: All data values are relative to the MLLW.

Elevations on Mean Lower Low Water

Station: 9455920, Anchorage, AK
Status: Accepted (Jun 03 2019)
Units: Feet
Control Station:
T.M.: 0
Epoch: 1983-2001
Datum: MLLW
DatumValueDescription
MHHW29.16Mean Higher-High Water
MHW28.43Mean High Water
MTL15.34Mean Tide Level
MSL16.47Mean Sea Level
DTL14.58Mean Diurnal Tide Level
MLW2.25Mean Low Water
MLLW0.00Mean Lower-Low Water
NAVD8810.77North American Vertical Datum of 1988
STND-6.27Station Datum
GT29.16Great Diurnal Range
MN26.19Mean Range of Tide
DHQ0.73Mean Diurnal High Water Inequality
DLQ2.25Mean Diurnal Low Water Inequality
HWI3.65Greenwich High Water Interval (in hours)
LWI10.41Greenwich Low Water Interval (in hours)
Max Tide34.86Highest Observed Tide
Max Tide Date & Time11/06/2002 04:12Highest Observed Tide Date & Time
Min Tide-6.39Lowest Observed Tide
Min Tide Date & Time12/25/1999 12:42Lowest Observed Tide Date & Time
HAT33.78Highest Astronomical Tide
HAT Date & Time11/16/2016 04:18HAT Date and Time
LAT-5.04Lowest Astronomical Tide
LAT Date & Time01/15/2036 12:00LAT Date and Time
Tidal Datum Analysis Periods
01/01/1997 - 12/31/2001


Products available at 9455920 Anchorage, AK