U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 8
Station ID: 9463888 PUBLICATION DATE: 03/11/2025
Name: ST GEORGE, BERING SEA
AK
NOAA Chart: US4AK3QD Latitude: 56° 36.2' N ( 56.60328)
USGS Quad: PRIBILOF ISLANDS A-2 NW Longitude: 169° 33.0' W (-169.54956)
To reach the tide station from the St. George airport, proceed SE on Airport
Road for 0.8 km (0.5 mi), to the intersection with Zapadni Bay Road, turn left
onto Zapadni Bay Road and proceed NE for 8.0 km (5.0 mi) following the road into
St. George Village and to the St. George Sealing Plant, a white,
horseshoe-shaped historical building, then proceed west about 40 m (130 ft) down
to the coast and the shorter of 2 concrete wharfs. The tide station is inside
of an existing 3 m by 3 m (9 ft by 9 ft) concrete structure at the base of the
shorter concrete wharf. The water level sensors are located about 24 m (80 ft)
WNW from the concrete structure, near the NW corner of the wharf. The bench
mark network extends from the east most point of St. George Village on the
bluffs, south and uphill towards the cemetery, and west along Zapadni Bay Road.
T I D A L B E N C H M A R K S
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 8
Station ID: 9463888 PUBLICATION DATE: 03/11/2025
Name: ST GEORGE, BERING SEA
AK
NOAA Chart: US4AK3QD Latitude: 56° 36.2' N ( 56.60328)
USGS Quad: PRIBILOF ISLANDS A-2 NW Longitude: 169° 33.0' W (-169.54956)
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: STG-1 2018
DESIGNATION: STG 1
MONUMENTATION: Tidal Station disk VM#: 24932
AGENCY: USACE IDB PID#:
SETTING CLASSIFICATION: Rock outcrop OPUS PID#: BBGD37
LATITUDE: 56° 36.2' N ( 56.60339) LONGITUDE: 169° 32.5' W (-169.54185)
The bench mark is a disk set in a rock outcropping 68.6 m (225.1 ft) NE of the
road intersection north of St. George school and 0.5 m (1.6 ft) NW of an orange
carsonite post.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 8
Station ID: 9463888 PUBLICATION DATE: 03/11/2025
Name: ST GEORGE, BERING SEA
AK
NOAA Chart: US4AK3QD Latitude: 56° 36.2' N ( 56.60328)
USGS Quad: PRIBILOF ISLANDS A-2 NW Longitude: 169° 33.0' W (-169.54956)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: STG-2 2018
DESIGNATION: STG 2
MONUMENTATION: Tidal Station disk VM#: 24933
AGENCY: USACE IDB PID#:
SETTING CLASSIFICATION: Rock outcrop OPUS PID:
LATITUDE: 56° 36.2' N ( 56.60300) LONGITUDE: 169° 32.9' W (-169.54916)
The bench mark is a disk set in a rock outcropping, 29.0 m (95.1 ft) south of an
abandoned building, 7.6 m (24.9 ft) south of the north corner of a concrete ramp
and 2.2 m (7.2 ft) NW of an orange carsonite post.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 8
Station ID: 9463888 PUBLICATION DATE: 03/11/2025
Name: ST GEORGE, BERING SEA
AK
NOAA Chart: US4AK3QD Latitude: 56° 36.2' N ( 56.60328)
USGS Quad: PRIBILOF ISLANDS A-2 NW Longitude: 169° 33.0' W (-169.54956)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: STG-3 2018
DESIGNATION: STG 3
MONUMENTATION: Flange-encased Rod VM#: 24934
AGENCY: USACE IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 56° 36.0' N ( 56.59977) LONGITUDE: 169° 32.4' W (-169.54083)
The bench mark is a stainless steel rod set in the grass north of the road, 53.3
m (174.9 ft) east of the gate post at the top of the hill past the cemetery, 2.9
m (9.5 ft) north of cemetery hill road, and 0.6 m (2.0 ft) south of an orange
carsonite post. The datum point is set below grade, being the top of a 9/16
stainless steel rod driven 3.3 m (10.8 ft) to refusal and encased in a 6-inch
(15 cm) diameter sand filled pvc pipe with logo cap.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 8
Station ID: 9463888 PUBLICATION DATE: 03/11/2025
Name: ST GEORGE, BERING SEA
AK
NOAA Chart: US4AK3QD Latitude: 56° 36.2' N ( 56.60328)
USGS Quad: PRIBILOF ISLANDS A-2 NW Longitude: 169° 33.0' W (-169.54956)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: STG-4 2018
DESIGNATION: STG 4
MONUMENTATION: Flange-encased Rod VM#: 24935
AGENCY: USACE IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 56° 36.0' N ( 56.60039) LONGITUDE: 169° 33.4' W (-169.55653)
The bench mark is a stainless steel rod set in the grass south of Zapadni bay
road, 18.3 m (60.0 ft) south of the road and 0.5 m (1.6 ft) north of an orange
carsonite post. The datum point is set below grade, being the top of a 9/16
stainless steel rod driven 1.2 m (4 ft) to refusal and encased in a 6-inch (15
cm) diameter sand filled pvc pipe with logo cap.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 8
Station ID: 9463888 PUBLICATION DATE: 03/11/2025
Name: ST GEORGE, BERING SEA
AK
NOAA Chart: US4AK3QD Latitude: 56° 36.2' N ( 56.60328)
USGS Quad: PRIBILOF ISLANDS A-2 NW Longitude: 169° 33.0' W (-169.54956)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: STG-5 2018
DESIGNATION: STG 5
MONUMENTATION: Flange-encased Rod VM#: 24936
AGENCY: USACE IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID#: BBGC98
LATITUDE: 56° 36.0' N ( 56.60072) LONGITUDE: 169° 33.8' W (-169.56409)
The bench mark is a stainless steel rod set in the grass north of Zapadni bay
road, 16.0 m (52.5 ft) north of the road, 6.1 m (20.0 ft) NW of an abandoned
electrical transformer, and 0.5 m (1.6 ft) south of an orange carsonite post.
The datum point is set below grade, being the top of a 9/16 stainless steel rod
driven 1.8 m (6 ft) to refusal and encased in a 6-inch (15 cm) diameter sand
filled pvc pipe with logo cap.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 7 of 8
Station ID: 9463888 PUBLICATION DATE: 03/11/2025
Name: ST GEORGE, BERING SEA
AK
NOAA Chart: US4AK3QD Latitude: 56° 36.2' N ( 56.60328)
USGS Quad: PRIBILOF ISLANDS A-2 NW Longitude: 169° 33.0' W (-169.54956)
T I D A L D A T U M S
Tidal datums at ST GEORGE, BERING SEA based on:
LENGTH OF SERIES: 3 MONTHS
TIME PERIOD: June 2024 - August 2024
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 9464212 VILLAGE COVE, ST. PAUL ISLAND
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 1.053
MEAN HIGH WATER MHW = 0.982
MEAN TIDE LEVEL MTL = 0.622
MEAN SEA LEVEL MSL = 0.611
MEAN LOW WATER MLW = 0.263
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum NAVD88 = -0.089
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
STG-1 2018 8.902 7.920
STG-2 2018 8.301 7.319
STG-3 2018 57.371 56.389
STG-4 2018 31.653 30.671
STG-5 2018 24.187 23.205
Foot Notes:
Bench mark STG-3 2018 is based on one differential leveling connection and do
not meet the quality control standards of the National Ocean Service. Therefore,
caution should be used when deriving elevations for these marks.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 8 of 8
Station ID: 9463888 PUBLICATION DATE: 03/11/2025
Name: ST GEORGE, BERING SEA
AK
NOAA Chart: US4AK3QD Latitude: 56° 36.2' N ( 56.60328)
USGS Quad: PRIBILOF ISLANDS A-2 NW Longitude: 169° 33.0' W (-169.54956)
D E F I N I T I O N S
Mean Sea Level (MSL) is a tidal datum determined over a 19-year National Tidal
Datum Epoch. It pertains to local mean sea level and should not be confused
with the fixed datums of North American Vertical Datum of 1988 (NAVD88).
NAVD88 is a fixed datum derived from a simultaneous, least squares, minimum
constraint adjustment of Canadian/Mexican/United States leveling observations.
Local mean sea level observed at Father Point/Rimouski, Canada was held fixed as
the single initial constraint. NAVD88 replaces NGVD29 as the national
standard geodetic reference for heights. Bench mark elevations relative to
NAVD88 are available from NGS through the World Wide Web at
National Geodetic Survey.
NGVD29 is a fixed datum adopted as a national standard geodetic reference for
heights but is now considered superseded. NGVD29 is sometimes referred to as
Sea Level Datum of 1929 or as Mean Sea Level on some early issues of Geological
Survey Topographic Quads. NGVD29 was originally derived from a general
adjustment of the first-order leveling networks of the U.S. and Canada after
holding mean sea level observed at 26 long term tide stations as fixed.
Numerous local and wide-spread adjustments have been made since establishment in
1929. Bench mark elevations relative to NGVD29 are available from the National
Geodetic Survey (NGS) data base via the World Wide Web at
National Geodetic Survey.
NAVD88 and NGVD29 are fixed geodetic datums whose elevation relationships to
local MSL and other tidal datums may not be consistent from one location to
another.
The Vertical Mark Number (VM#) and PID# shown on the bench mark sheet are unique
identifiers for bench marks in the tidal and geodetic databases, respectively.
Each bench mark in either database has a single, unique VM# and/or PID# assigned.
Where both VM# and PID# are indicated, both tidal and geodetic elevations are
available for the bench mark listed. The NGS's Integrated Data Base (IDB PID)
provides geodetic datum based on traditionally leveled and bluebooked ties to
the National Spatial Reference System(NSRS) https://www.ngs.noaa.gov/datasheets/.
The NGS Online Positioning User Service (OPUS PID) provides geodetic datum based
on GPS position & tie it to the NSRS https://www.ngs.noaa.gov/OPUS/.
The NAVD88 elevation is shown on the Elevations of Tidal Datums Table Referred
to MLLW only when two or more of the bench marks listed have NAVD88 elevations.
The NAVD88 elevation relationship shown in the table is derived from an average
of several bench mark elevations relative to tide station datum. As a result of
this averaging, NAVD88 bench mark elevations computed indirectly from the tidal
datums elevation table may differ slightly from NAVD88 elevations listed for
each bench mark in the NGS database.