U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
Station ID: 9450551 PUBLICATION DATE: 05/13/2008
Name: CRAIG, KLAWOCK INLET
AK
NOAA Chart: 17405 Latitude: 55° 29.3' N ( 55.48830)
USGS Quad: CRAIG (B-4) Longitude: 133° 8.5' W (-133.14200)
To reach the tidal bench marks from Ketchikan, go NW approximately 56 km (30 nm)
near the village of Kasaan, then to a point 0.5 km (0.3 nm) SE of the village of
Kasaan, at the historic location of the U.S. Coast Guard light and day marker.
The tidal bench marks are located along the beach. The tide gauge was located
near the historic site.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 0551 A 2007
DESIGNATION: 945 0551 A
MONUMENTATION: Tidal Station disk VM#: 18516
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete wing wall OPUS PID#: BBFP37
LATITUDE: 55° 29.3' N ( 55.48830) LONGITUDE: 133° 8.5' W (-133.14200)
The primary bench mark is a disk set flush in a 0.2 m (0.5 ft) wide south wing
wall where the gravel access road ends and the concrete dock begins, 52.80 m
(173.2 ft) WSW of bench mark 945 0551 B, 30.40 m (99.7 ft) SW of the SW corner
of the green Petro Marine Services building, 12.30 m (40.4 ft) east of the
inside corner of the "L" shaped dock, 3.52 m (11.5 ft) south of the centerline
of the road at the transition from gravel to concrete, and 1.60 m (5.2 ft) NW of
a red fire hydrant.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
Station ID: 9450551 PUBLICATION DATE: 05/13/2008
Name: CRAIG, KLAWOCK INLET
AK
NOAA Chart: 17405 Latitude: 55° 29.3' N ( 55.48830)
USGS Quad: CRAIG (B-4) Longitude: 133° 8.5' W (-133.14200)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 0551 B 2007
DESIGNATION: 945 0551 B
MONUMENTATION: Tidal Station disk VM#: 18517
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete pad OPUS PID:
LATITUDE: 55° 29.3' N ( 55.48830) LONGITUDE: 133° 8.5' W (-133.14200)
The bench mark is a disk set flush in the concrete pad of the SE corner of the
Petro Marine Services building on the north side of the gravel access road and
just east of the dock, 52.80 m (173.2 ft) ENE of bench mark 945 0551 A, 23.80 m
(78.1 ft) east of the SW corner of the building, 14.50 m (47.6 ft) north of the
guardrail on the south side of the gravel road, 7.14 m (23.4 ft) east of the
east edge of the overhead door on the south side of the building, 0.75 m (2.5
ft) WSW of the SE corner of the building, and 0.55 m (1.8 ft) south of the south
face of the building.
BENCH MARK STAMPING: 0551 C 2007
DESIGNATION: 945 0551 C
MONUMENTATION: Tidal Station disk VM#: 18518
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete wing wall OPUS PID#: BBBG32
LATITUDE: 55° 29.3' N ( 55.48830) LONGITUDE: 133° 8.4' W (-133.14000)
The bench mark is a disk set flush in the top of the 0.20 m (0.7 ft) wide by
1.00 m (3.3 ft) high SW concrete wing wall on the bridge on the access road to
the port and dock, 27.50 m (90.2 ft) NE of a red fire hydrant, 24.75 m (81.2 ft)
NE of a power and light pole, 18.60 m (61.0 ft) SW of the NE edge of the bridge
at the wing wall, and 3.10 m (10.2 ft) SE of the centerline of the access road
at the west edge of the bridge.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
Station ID: 9450551 PUBLICATION DATE: 05/13/2008
Name: CRAIG, KLAWOCK INLET
AK
NOAA Chart: 17405 Latitude: 55° 29.3' N ( 55.48830)
USGS Quad: CRAIG (B-4) Longitude: 133° 8.5' W (-133.14200)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 0551 D 2007
DESIGNATION: 945 0551 D
MONUMENTATION: Tidal Station disk VM#: 18519
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete anchor OPUS PID#: BBBG32
LATITUDE: 55° 29.4' N ( 55.49000) LONGITUDE: 133° 8.3' W (-133.13800)
The bench mark is a disk set flush in a 2.4 m x 1.82 m x 0.45 m (7.9 ft x 6.0 ft
x 1.5 ft) high concrete anchor which is above the concrete boat ramp, 68.1 m
(223.4 ft) west of bench mark 945 0551 E, 30.0 m (98.4 ft) west of the NW corner
of the gravel staging area, 6.85 m (22.5 ft) north of the south edge of the
concrete ramp, 2.00 m (6.6 ft) north of the south edge of the concrete anchor,
and 0.75 m (2.5 ft) east of the west edge of the concrete anchor.
BENCH MARK STAMPING: 0551 E 2007
DESIGNATION: 945 0551 E
MONUMENTATION: Tidal Station disk VM#: 18520
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete pad OPUS PID:
LATITUDE: 55° 29.4' N ( 55.49000) LONGITUDE: 133° 8.3' W (-133.13800)
The bench mark is a disk set flush in the center of the east end of a 6.10 m
(20.0 ft) x 18.2 m (59.7 ft) concrete pad with a longitudinal drain in the NW
corner of the staging area, 68.1 m (223.4 ft) east of bench mark 945 0551 D,
61.20 m (200.8 ft) north of the centerline of the access road, 17.70 m (58.1 ft)
east of the west edge of the pad, 5.50 m (18.0 ft) south of the guardrail on the
north side of the staging area, 3.00 m (9.8 ft) south of the north edge of the
concrete pad, and 0.54 m (1.8 ft) west of the east edge of the concrete pad.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
Station ID: 9450551 PUBLICATION DATE: 05/13/2008
Name: CRAIG, KLAWOCK INLET
AK
NOAA Chart: 17405 Latitude: 55° 29.3' N ( 55.48830)
USGS Quad: CRAIG (B-4) Longitude: 133° 8.5' W (-133.14200)
T I D A L D A T U M S
Tidal datums at CRAIG, KLAWOCK INLET based on:
LENGTH OF SERIES: 2 MONTHS
TIME PERIOD: May 2007 - June 2007
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 9451600 SITKA, BARONOF ISLAND, SITKA SOUND
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 3.101
MEAN HIGH WATER MHW = 2.842
MEAN TIDE LEVEL MTL = 1.630
MEAN SEA LEVEL MSL = 1.627
MEAN LOW WATER MLW = 0.418
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
0551 A 2007 4.936 2.094
0551 B 2007 5.245 2.403
0551 C 2007 5.500 2.658
0551 D 2007 4.728 1.886
0551 E 2007 5.568 2.726
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
Station ID: 9450551 PUBLICATION DATE: 05/13/2008
Name: CRAIG, KLAWOCK INLET
AK
NOAA Chart: 17405 Latitude: 55° 29.3' N ( 55.48830)
USGS Quad: CRAIG (B-4) Longitude: 133° 8.5' W (-133.14200)
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.