U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 6
Station ID: 9418723 PUBLICATION DATE: 04/21/2014
Name: FIELDS LANDING, HUMBOLDT BAY
CA
NOAA Chart: 18622 Latitude: 40° 43.4' N ( 40.72330)
USGS Quad: FIELDS LANDING Longitude: 124° 13.3' W (-124.22200)
To reach the tidal bench marks fromthe Eureka exit of U.S. Highway 101, proceed
11.3 km (7.0 mi) south on U.S. HIghway 101 to the Fields Landing Road (1st
Street) exit, then proceed south on Fields Landing Road to Railroad Avenue, then
turn right and proceed west on Railroad Avenue until the road deadends at a
wooden wharf. The bench marks are along Railroad Avenue and Fields Landing
Road. The tide gage and staff were located on the inside of the north corner of
the wharf adjacent to channel mark 11.
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 6
Station ID: 9418723 PUBLICATION DATE: 04/21/2014
Name: FIELDS LANDING, HUMBOLDT BAY
CA
NOAA Chart: 18622 Latitude: 40° 43.4' N ( 40.72330)
USGS Quad: FIELDS LANDING Longitude: 124° 13.3' W (-124.22200)
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: P 1087 1967
DESIGNATION: P 1087
MONUMENTATION: Bench Mark disk VM#: 8714
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: LV0263
SETTING CLASSIFICATION: Concrete guardrail OPUS PID:
LATITUDE: 40° 43.5' N ( 40.72472) LONGITUDE: 124° 12.9' W (-124.21489)
The benchmark is a disk located in top of and 0.30 m (1.0 ft) north of the south
end of the east concrete bridge rail of the Orchard Avenue Overpass of the
Highway, at milepost 72.03, 5.50 m (18.0 ft) east of the centerline of the north
bound lanes of the Highway, and 1.10 (3.6 ft) above the level of the Highway.
BENCH MARK STAMPING: NO 7 RESET 1961
DESIGNATION: 941 8723 TIDAL 7 RESET
MONUMENTATION: Tidal Station disk VM#: 8712
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: LV0655
SETTING CLASSIFICATION: Curb OPUS PID:
LATITUDE: 40° 43.4' N ( 40.72378) LONGITUDE: 124° 13.0' W (-124.21586)
To reach the benchmark from the intersection of Fields Landing Drive and Central
Avenue in Fields Landing, proceed to the concrete curb along the west side of
the Drive, 22.90 m (75.1 ft) west of the centerline of the Drive, 10.60 m (34.8
ft) south of the center of the Avenue, 0.90 m (3.0 ft) SE of the NE corner of
the Silver Side Motel office, 0.40 m (1.3 ft) east of the east face of the
building, and level with the motel driveway.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 6
Station ID: 9418723 PUBLICATION DATE: 04/21/2014
Name: FIELDS LANDING, HUMBOLDT BAY
CA
NOAA Chart: 18622 Latitude: 40° 43.4' N ( 40.72330)
USGS Quad: FIELDS LANDING Longitude: 124° 13.3' W (-124.22200)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: Q 1087 1967
DESIGNATION: Q 1087
MONUMENTATION: Bench Mark disk VM#: 8715
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: LV0264
SETTING CLASSIFICATION: Concrete guardrail OPUS PID:
LATITUDE: 40° 44.2' N ( 40.73592) LONGITUDE: 124° 12.6' W (-124.21042)
The benchmark is a disk located in the SW end of the SE concrete bridge rail of
the Highway Overpass of King Salmon Avenue, 6.10 m (20.0 ft) SE of the
centerline of the north bound lanes of the Highway, and 1.10 m (3.6 ft) above
the level of the Highway.
BENCH MARK STAMPING: 8739 B TIDAL
DESIGNATION: 941 8739 B TIDAL
MONUMENTATION: Tidal Station disk VM#: 20945
AGENCY: National Ocean Survey IDB PID#: LV0653
SETTING CLASSIFICATION: Galvanized steel rod with out sleeve OPUS PID:
LATITUDE: 40° 43.5' N ( 40.72500) LONGITUDE: 124° 13.0' W (-124.21631)
The benchmark is S of the SW corner of Red Bluff Bridge, 17.50 m (57.4 ft) NW of
the center of a road and gate leading to the King Salmon Seawater Rearing Ponds
, 9.80 m (32.2 ft) SW of the centerline of the road, 4.10 m (13.5 ft) NW of the
center of a track road, 0.60 m (2.0 ft) below the level of the road, and 0.30 m
(1.0 ft) west of a witness post. The disk is encased in a 4-inch pipe and is
flush with the ground surface.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 6
Station ID: 9418723 PUBLICATION DATE: 04/21/2014
Name: FIELDS LANDING, HUMBOLDT BAY
CA
NOAA Chart: 18622 Latitude: 40° 43.4' N ( 40.72330)
USGS Quad: FIELDS LANDING Longitude: 124° 13.3' W (-124.22200)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 8739 C TIDAL 1978
DESIGNATION: 941 8739 C TIDAL
MONUMENTATION: Tidal Station disk VM#: 20946
AGENCY: National Ocean Survey IDB PID#: LV0652
SETTING CLASSIFICATION: Galvanize steel rod with out sleeve OPUS PID:
LATITUDE: 40° 44.2' N ( 40.73714) LONGITUDE: 124° 12.7' W (-124.21158)
The benchmark is located 11.00 m (36.1 ft) SW of the centerline of the road and
3.50 m (11.5 ft) NW of and level with the center of a paved road. The disk is
encased in a 4-inch pipe and is flush with the ground surface.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 6
Station ID: 9418723 PUBLICATION DATE: 04/21/2014
Name: FIELDS LANDING, HUMBOLDT BAY
CA
NOAA Chart: 18622 Latitude: 40° 43.4' N ( 40.72330)
USGS Quad: FIELDS LANDING Longitude: 124° 13.3' W (-124.22200)
T I D A L D A T U M S
Tidal datums at FIELDS LANDING, HUMBOLDT BAY based on:
LENGTH OF SERIES: 3 MONTHS
TIME PERIOD: December 2010 - February 2011
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 9418767 NORTH SPIT, HUMBOLDT BAY
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 2.102
MEAN HIGH WATER MHW = 1.885
MEAN TIDE LEVEL MTL = 1.133
MEAN SEA LEVEL MSL = 1.131
MEAN LOW WATER MLW = 0.381
North American Vertical Datum NAVD88 = 0.143
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
P 1087 1967 10.939 9.054
NO 7 RESET 1961 3.253 1.368
Q 1087 1967 9.906 8.021
8739 B TIDAL 2.723 0.838
8739 C TIDAL 1978 2.913 1.028
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 6
Station ID: 9418723 PUBLICATION DATE: 04/21/2014
Name: FIELDS LANDING, HUMBOLDT BAY
CA
NOAA Chart: 18622 Latitude: 40° 43.4' N ( 40.72330)
USGS Quad: FIELDS LANDING Longitude: 124° 13.3' W (-124.22200)
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.