U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 6
Station ID: 9455869 PUBLICATION DATE: 08/15/2018
Name: NORTH FORELAND
AK
NOAA Chart: 16663 Latitude: 61° 2.6' N ( 61.04331)
USGS Quad: TYONEK (A-3) Longitude: 151° 9.8' W (-151.16300)
To reach the bench marks from the south end of the Tyonek airstrip, proceed SSW
on a gravel road 0.7 km (0.4 mi) to a sharp bend to the right, turn right and
proceed NW and then immediately turn left and proceed WNW on a gravel road 1.6
km (1.0 mi) to a fork in the road, follow the gravel road to the left and
continue WNW 0.3 km (0.2 mi) to a sharp bend to the left, follow the gravel road
around the bend and continue south 0.5 km (0.3 mi) past the turn to the right
for Kaldachabuna Lake, continue south and west around the SE side of
Kaldachabuna Lake 2.3 km (1.4 mi), then follow the sharp bend to the left and
continue SSE 0.8 km (0.5 mi) to the abandoned wood chip facility, turn left and
proceed east 0.5 km (0.3 mi) across the gravel lot to the beginning of the
Tyonek pier. The bench marks are set in concrete structures and foundations
among the abandoned wood chip facility. The tide station is located at the end
of the pier.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 5869 H 1998
DESIGNATION: 945 5869 H
MONUMENTATION: Tidal Station disk VM#: 16060
AGENCY: LCMF, Inc. IDB PID#:
SETTING CLASSIFICATION: Concrete abutment OPUS PID#: BBBF25
LATITUDE: 61° 2.8' N ( 61.04619) LONGITUDE: 151° 10.1' W (-151.16753)
The primary bench mark is a disk set flush in a concrete abutment NE of the
shoreward end of the Tyonek pier, 36.60 m (120.1 ft) SSE of bench mark 945 5869
D, 19.17 m (62.9 ft) south of the SW corner of a 9 m (30 ft) square green steel
building, 5 m (16 ft) ENE of the centerline of the pier, 3.99 m (13.1 ft) SSE of
the center of the southern most conveyor support, and 0.82 m (2.7 ft) below the
steel deck of the pier.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 6
Station ID: 9455869 PUBLICATION DATE: 08/15/2018
Name: NORTH FORELAND
AK
NOAA Chart: 16663 Latitude: 61° 2.6' N ( 61.04331)
USGS Quad: TYONEK (A-3) Longitude: 151° 9.8' W (-151.16300)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 5869 D 1977
DESIGNATION: 945 5869 D
MONUMENTATION: Tidal Station disk VM#: 14786
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete foundation OPUS PID:
LATITUDE: 61° 2.8' N ( 61.04647) LONGITUDE: 151° 10.1' W (-151.16786)
The bench mark is a disk set flush in the WSW end of the concrete foundation for
the fifth conveyor support NNW from the shoreward end of the pier, 70.80 m
(232.3 ft) SSE of bench mark 945 5869 J, 36.60 m (120.1 ft) NNW of bench mark
945 5869 H, 8.80 m (28.9 ft) NW of the NW corner of a 9 m (30 ft) square green
steel building, and 3.3 m (11 ft) NNW of the centerline of a track road.
BENCH MARK STAMPING: 5869 E 1977
DESIGNATION: 945 5869 E
MONUMENTATION: Tidal Station disk VM#: 14787
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete foundation OPUS PID:
LATITUDE: 61° 2.8' N ( 61.04717) LONGITUDE: 151° 10.0' W (-151.16636)
The bench mark is a disk set flush in the NE corner of a 2 m (6 ft) x 3 m (10
ft) concrete pad for a small white shed among thick alder brush, 21.30 m (70 ft)
north of the centerline of a track road, 14.20 m (46 ft) SSE from the top of a
dirt berm around a large red tank, 0.70 m (2.3 ft) NE of the NE corner of the
white shed, and 0.19 m (0.6 ft) SW of the NE corner of the concrete pad.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 6
Station ID: 9455869 PUBLICATION DATE: 08/15/2018
Name: NORTH FORELAND
AK
NOAA Chart: 16663 Latitude: 61° 2.6' N ( 61.04331)
USGS Quad: TYONEK (A-3) Longitude: 151° 9.8' W (-151.16300)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 5869 F 1998
DESIGNATION: 945 5869 F
MONUMENTATION: Chiseled Cross VM#: 16058
AGENCY: LCMF, Inc. IDB PID#:
SETTING CLASSIFICATION: Pavement OPUS PID:
LATITUDE: 61° 2.6' N ( 61.04330) LONGITUDE: 151° 9.8' W (-151.16300)
The bench mark is a cross chiseled on a heavy steel plate welded onto the top
surface of the southern end of the Tyonek pier and partially obscured by a
welded metal bumper, 93.24 m (305.9 ft) SE of bench mark 945 5869 N, 31.71 m
(104.0 ft) SE of bench mark 945 5869 G, and 12.98 m (42.6 ft) SE of the SW
corner of a small wooden shed at the end of the pier.
BENCH MARK STAMPING: 5869 J 1998
DESIGNATION: 945 5869 J
MONUMENTATION: Tidal Station disk VM#: 16061
AGENCY: LCMF, Inc. IDB PID#:
SETTING CLASSIFICATION: Concrete foundation OPUS PID:
LATITUDE: 61° 2.8' N ( 61.04706) LONGITUDE: 151° 10.1' W (-151.16842)
The bench mark is a disk set flush in a concrete foundation at the right angle
bend in the conveyor, 81.04 m (265.9 ft) ENE of bench mark 945 5869 K, 70.80 m
(232.3 ft) NNW of bench mark 945 5869 D, 1.20 m (3.9 ft) NNW of the NW corner of
a corrugated metal shed housing electrical components, and 0.30 m (1.0 ft) east
of the west side of the concrete foundation.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 6
Station ID: 9455869 PUBLICATION DATE: 08/15/2018
Name: NORTH FORELAND
AK
NOAA Chart: 16663 Latitude: 61° 2.6' N ( 61.04331)
USGS Quad: TYONEK (A-3) Longitude: 151° 9.8' W (-151.16300)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 5869 K 1998
DESIGNATION: 945 5869 K
MONUMENTATION: Tidal Station disk VM#: 16062
AGENCY: LCMF, Inc. IDB PID#:
SETTING CLASSIFICATION: Concrete foundation OPUS PID:
LATITUDE: 61° 2.8' N ( 61.04683) LONGITUDE: 151° 10.2' W (-151.16972)
The bench mark is a disk set flush in the top of a sloping structure at the base
of a derelict chip hopper, 81.04 m (265.9 ft) WSW of bench mark 945 5869 J,
10.95 m (35.9 ft) WSW of the concrete base of the second chip hopper, 1.92 m
(6.3 ft) north of the SE corner of the concrete structure, 0.46 m (1.5 ft) ENE
of the east side of the hopper's concrete base, and 1.0 m (3 ft) below a large
pile of wood chips.
BENCH MARK STAMPING: 5869 N 1999
DESIGNATION: 945 5869 N
MONUMENTATION: Chiseled Cross VM#: 16065
AGENCY: LCMF, Inc. IDB PID#:
SETTING CLASSIFICATION: Pier OPUS PID:
LATITUDE: 61° 2.6' N ( 61.04339) LONGITUDE: 151° 9.9' W (-151.16450)
The bench mark is a cross chiseled on the top surface of the NE side of the
steel Tyonek pier, 354.3 (1162 ft) SE of the beginning of the metal rail on the
NE side of the dock, 97.61 m (320.2 ft) SE of bench mark 9455869 M, 80.18 m
(263.1 ft) NW of the NW corner of a small wooden shed at the end of the pier,
and 61.53 m (201.9 ft) NW of bench mark 9455869 G.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 6
Station ID: 9455869 PUBLICATION DATE: 08/15/2018
Name: NORTH FORELAND
AK
NOAA Chart: 16663 Latitude: 61° 2.6' N ( 61.04331)
USGS Quad: TYONEK (A-3) Longitude: 151° 9.8' W (-151.16300)
T I D A L D A T U M S
Tidal datums at NORTH FORELAND based on:
LENGTH OF SERIES: 3 MONTHS
TIME PERIOD: June 1999 - August 1999
TIDAL EPOCH: 2012-2016
CONTROL TIDE STATION: 9455760 NIKISKI, COOK INLET
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 6.387
MEAN HIGH WATER MHW = 6.178
MEAN SEA LEVEL MSL = 3.506
MEAN TIDE LEVEL MTL = 3.418
MEAN LOW WATER MLW = 0.659
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
5869 H 1998 8.969 2.791
5869 D 1977 8.944 2.766
5869 E 1977 8.720 2.542
5869 F 1998 9.692 3.514
5869 J 1998 8.967 2.789
5869 K 1998 10.359 4.181
5869 N 1999 9.648 3.470
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 6
Station ID: 9455869 PUBLICATION DATE: 08/15/2018
Name: NORTH FORELAND
AK
NOAA Chart: 16663 Latitude: 61° 2.6' N ( 61.04331)
USGS Quad: TYONEK (A-3) Longitude: 151° 9.8' W (-151.16300)
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.