U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
Station ID: 9455159 PUBLICATION DATE: 04/21/2003
Name: CRATER BAY
AK
NOAA Chart: 16682 Latitude: 59° 42.8' N ( 59.71330)
USGS Quad: BLYING SOUND (D-8) Longitude: 149° 47.2' W (-149.78700)
To reach the tidal benchmarks from Seward via boat, proceed 15 km (8 nm) SSE
along Resurrection Bay to Calisto Head, then 32.5 km (17.6 nm) south along
Resurrection Bay to Aialik Cape, then 9.1 km (4.9 nm) west across Aialik Bay to
the axis of Aialik Bay north of Harbor Island, then 10.4 km (5.6 nm) SSW to the
center of the passage between Aligo Point and the southern tip of Granite
Island, then 9.5 km (5.1 nm) NW along Granite Passage, then 4.0 km (2.2 nm) NE
along Crater Bay to the tide station. The benchmarks are located along the
shoreline. The tide station was located on the hillside in the trees above bench
mark 9455159 B 2000.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 9455159 B 2000
DESIGNATION: 945 5159 B
MONUMENTATION: Tidal Station disk VM#: 16384
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Rock outcrop OPUS PID:
LATITUDE: 59° 42.8' N ( 59.71330) LONGITUDE: 149° 47.0' W (-149.78300)
The primary benchmark is set in a large rock outcropping which produces a small
point on the NE side of Crater Bay, 79 m (259 ft) west of benchmark 9455159 A
2000, 24 m (79 ft) south of benchmark 9455159 C 2000, 4 m (12 ft) from the
apparent high water line, 2 m (8 ft) from the edge of the vegetation, and 1 m
(4 ft) below the vegetation line.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
Station ID: 9455159 PUBLICATION DATE: 04/21/2003
Name: CRATER BAY
AK
NOAA Chart: 16682 Latitude: 59° 42.8' N ( 59.71330)
USGS Quad: BLYING SOUND (D-8) Longitude: 149° 47.2' W (-149.78700)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 9455159 A 2000
DESIGNATION: 945 5159 A
MONUMENTATION: Tidal Station disk VM#: 16383
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Rock outcrop OPUS PID:
LATITUDE: 59° 42.8' N ( 59.71330) LONGITUDE: 149° 47.0' W (-149.78300)
The benchmark is set in a large sloping rock outcrop, 79 m (259 ft) east of
benchmark 9455159 B 2000, 1 m (3 ft) from the apparent high water line, 0.3 m (1
ft) from the edge of the rock, and 2 m (5 ft) below the vegetation line.
BENCH MARK STAMPING: 9455159 C 2000
DESIGNATION: 945 5159 C
MONUMENTATION: Tidal Station disk VM#: 16389
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Rock outcrop OPUS PID:
LATITUDE: 59° 42.8' N ( 59.71330) LONGITUDE: 149° 47.1' W (-149.78500)
The benchmark is set in a 5 m x 2 m (15 ft x 5 ft) sloping rock outcrop, 24 m
(79 ft) north of benchmark 9455159 B 2000, 16 m (52 ft) SE of benchmark 9455159
D 2000, 0.3 m (1 ft) from the edge of the outdrop, and 2 m (5 ft) below the
vegetation line.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
Station ID: 9455159 PUBLICATION DATE: 04/21/2003
Name: CRATER BAY
AK
NOAA Chart: 16682 Latitude: 59° 42.8' N ( 59.71330)
USGS Quad: BLYING SOUND (D-8) Longitude: 149° 47.2' W (-149.78700)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 9455159 D 2000
DESIGNATION: 945 5159 D
MONUMENTATION: Tidal Station disk VM#: 16390
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Boulder OPUS PID:
LATITUDE: 59° 42.8' N ( 59.71330) LONGITUDE: 149° 47.1' W (-149.78500)
The benchmark is set in a 9 m x 2 m x 3 m (30 ft x 8 ft x 10 ft) high boulder,
23 m (75 ft) SE of benchmark 9455159 E 2000, 16 m (52 ft) NW of benchmark
9455159 C 2000, 6 m (20 ft) from the apparent high water line, 2 m (8 ft) from
the vegetation line, and 2 m (5 ft) below the vegetation line.
BENCH MARK STAMPING: 9455159 E 2000
DESIGNATION: 945 5159 E
MONUMENTATION: Tidal Station disk VM#: 16391
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Boulder OPUS PID:
LATITUDE: 59° 42.8' N ( 59.71330) LONGITUDE: 149° 47.1' W (-149.78500)
The benchmark is set in a small boulder point, 23 m (75 m) NW of benchmark
9455159 D 2000, 2 m (6 ft) SW of the base of a 5 m x 3 m x 3 m (15 ft x 10 ft x
10 ft) high boulder, and 2 m (6 ft) from the edge of the apparent high water
line.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
Station ID: 9455159 PUBLICATION DATE: 04/21/2003
Name: CRATER BAY
AK
NOAA Chart: 16682 Latitude: 59° 42.8' N ( 59.71330)
USGS Quad: BLYING SOUND (D-8) Longitude: 149° 47.2' W (-149.78700)
T I D A L D A T U M S
Tidal datums at CRATER BAY based on:
LENGTH OF SERIES: 3 Months
TIME PERIOD: August 2000 - October 2000
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 9455090 SEWARD, RESURRECTION BAY
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 3.266
MEAN HIGH WATER MHW = 2.988
MEAN SEA LEVEL MSL = 1.698
MEAN TIDE LEVEL MTL = 1.694
MEAN LOW WATER MLW = 0.400
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
9455159 B 2000 3.294 0.306
9455159 A 2000 4.030 1.042
9455159 C 2000 4.372 1.384
9455159 D 2000 4.857 1.869
9455159 E 2000 3.032 0.044
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
Station ID: 9455159 PUBLICATION DATE: 04/21/2003
Name: CRATER BAY
AK
NOAA Chart: 16682 Latitude: 59° 42.8' N ( 59.71330)
USGS Quad: BLYING SOUND (D-8) Longitude: 149° 47.2' W (-149.78700)
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.