U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 7
Station ID: 9414523 PUBLICATION DATE: 06/22/2020
Name: REDWOOD CITY, WHARF 5, S. F. BAY
CA
NOAA Chart: 18651 Latitude: 37° 30.4' N ( 37.50670)
USGS Quad: REDWOOD POINT Longitude: 122° 12.6' W (-122.21000)
To reach the tidal bench marks from U.S. Highway 101 exit at Seaport Boulevard
to Port of Redwood City, go 1.6 km (1 mi) NE of the freeway on the Seaport
Boulevard to the entrance gate to Wharf No 5 near the SW end of the port. The
bench marks are in the general vicinity along the coast. The tide gage is
located on the pier.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 4508 A 1997
DESIGNATION: 941 4508 A
MONUMENTATION: Tidal Station disk VM#: 13852
AGENCY: National Ocean Service (NOS) IDB PID:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID#: BBBF96
LATITUDE: 37° 30.5' N ( 37.50861) LONGITUDE: 122° 12.6' W (-122.21033)
The primary bench mark is a disk located at the S bend dirt area along Kerkner
Road, west of post office, 8 m (26 ft) east of centerline of the N/S running
segment of Herkner Road, 5.30 m (17.4 ft) SW of center of railroad tracks, 4.91
m (16.1 ft) NE of a fence with witness sign attached. The bench mark is set
0.20 m (0.7 ft) below grade, crimped to a stainless steel rod driven 15.5 m (51
ft) to refusal and encased in a 6 inch (15 cm) PVC pipe with a concrete kick
block.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 7
Station ID: 9414523 PUBLICATION DATE: 06/22/2020
Name: REDWOOD CITY, WHARF 5, S. F. BAY
CA
NOAA Chart: 18651 Latitude: 37° 30.4' N ( 37.50670)
USGS Quad: REDWOOD POINT Longitude: 122° 12.6' W (-122.21000)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 4508 B 1997
DESIGNATION: 941 4508 B
MONUMENTATION: Tidal Station disk VM#: 13853
AGENCY: National Ocean Service (NOS) IDB PID:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 37° 30.4' N ( 37.50733) LONGITUDE: 122° 12.6' W (-122.20925)
The bench mark is a disk located at the SW corner of the intersection of Seaport
Boulevard and Herkner Road, S of the post office, 20.70 m (67.9 ft) W of center
of Seaport Boulevard, 5.70 m (18.7 ft) W of center of railroad tracks, 4.39 m
(14.4 ft) S of the SE corner of the westernmost of two vault boxes, 2.59 m (8.5
ft) slope distance E of the top of a metal witness sign on a chain link fence, 2
m (7 ft) E of a chain link fence with witness sign attached and 0.33 m (1.1 ft)
E of an orange fiberglass witness post. The bench mark is set 0.40 m (1.3 ft)
below ground level, and crimped to the top of a rod driven 18.3 m (60 ft) to
refusal.
BENCH MARK STAMPING: 4508 C 1997
DESIGNATION: 941 4508 C
MONUMENTATION: Tidal Station disk VM#: 13854
AGENCY: National Ocean Service (NOS) IDB PID#: AH7470
SETTING CLASSIFICATION: Concrete pad OPUS PID#: AH7470
LATITUDE: 37° 30.5' N ( 37.50797) LONGITUDE: 122° 12.7' W (-122.21086)
The bench mark is a disk set in the SE corner of a 1.35 m x 1.35 m (4.4 ft x 4.4
ft) concrete block supporting a bollard located between Wharfs 4 and 5 at the
Port of Redwood City, 15.20 m (49.9 ft) W of junction of two railroad tracks,
10.12 m (33.2 ft) E of the concrete breakwater, 5.48 m (18.0 ft) north of a fire
hydrant with four yellow guard posts, and 0.50 m (1.6 ft) above ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 7
Station ID: 9414523 PUBLICATION DATE: 06/22/2020
Name: REDWOOD CITY, WHARF 5, S. F. BAY
CA
NOAA Chart: 18651 Latitude: 37° 30.4' N ( 37.50670)
USGS Quad: REDWOOD POINT Longitude: 122° 12.6' W (-122.21000)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: WHARF 4 1985
DESIGNATION: 941 4523 WHARF 4
MONUMENTATION: Bench Mark disk VM#: 13856
AGENCY: US Geological Survey (USGS) IDB PID:
SETTING CLASSIFICATION: Sea wall OPUS PID:
LATITUDE: 37° 30.6' N ( 37.50939) LONGITUDE: 122° 12.7' W (-122.21167)
The bench mark is a disk set into the seaward bullrail on the N end of the
catwalk leading to the S dolphin on Wharf 4, 5.80 m (19.0 ft) S of high voltage
box "E2", 2.20 m (7.2 ft) S of the second southernmost bollard, 1.70 m (5.6 ft)
from W wharf face, and 0.30 m (1.0 ft) above wharf deck.
BENCH MARK STAMPING: 4508 T 1998
DESIGNATION: 941 4508 T
MONUMENTATION: Tidal Station disk VM#: 14824
AGENCY: National Ocean Service (NOS) IDB PID:
SETTING CLASSIFICATION: Curb OPUS PID:
LATITUDE: 37° 30.4' N ( 37.50739) LONGITUDE: 122° 12.7' W (-122.21125)
The bench mark is a disk set in the S curb of the N ramp leading to Wharf 5 at
the Port of Redwood City, 14.60 m (47.9 ft) W of a light pole leading to the
pier, 10.0 m (32.8 ft) NW of SE end of curb, and 4.6 m (15.1 ft) S of center of
ramp.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 7
Station ID: 9414523 PUBLICATION DATE: 06/22/2020
Name: REDWOOD CITY, WHARF 5, S. F. BAY
CA
NOAA Chart: 18651 Latitude: 37° 30.4' N ( 37.50670)
USGS Quad: REDWOOD POINT Longitude: 122° 12.6' W (-122.21000)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 4508 U 1998
DESIGNATION: 941 4508 U
MONUMENTATION: Tidal Station disk VM#: 14825
AGENCY: National Ocean Service (NOS) IDB PID:
SETTING CLASSIFICATION: Sea wall OPUS PID:
LATITUDE: 37° 30.5' N ( 37.50867) LONGITUDE: 122° 12.7' W (-122.21100)
The bench mark is a disk set in a sea wall near a boat ramp at the Port of
Redwood City between Wharfs 4 and 5, 15.24 m (50.0 ft) W of center of road
leading to the Wharf 4, 5.50 m (18.0 ft) E of center of boat ramp, and 4.90 m
(16.1 ft) S of the N end of the sea wall.
BENCH MARK STAMPING: 4523 A 2009
DESIGNATION: 945 4523 A
MONUMENTATION: Metal Rod VM#: 19575
AGENCY: National Ocean Service (NOS) IDB PID:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 37° 30.5' N ( 37.50786) LONGITUDE: 122° 12.6' W (-122.20942)
The benchmark is set on the S side of Herkner Road, 20.8 m (68.2 ft) E of the
railroad switch along the S side of Hernker Road, 5.48 m (18.0 ft) S of the
center of Herkner Road, 3.0 m (9.8 ft) N of the center of the Port of Redwood
City railroad tracks, and 0.17 m (0.6 ft) N of the orange NOAA witness marker.
The bench mark is driven 17.1 m (56 ft) to refusal, encased in a 6-inch NOS logo
cap.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 7
Station ID: 9414523 PUBLICATION DATE: 06/22/2020
Name: REDWOOD CITY, WHARF 5, S. F. BAY
CA
NOAA Chart: 18651 Latitude: 37° 30.4' N ( 37.50670)
USGS Quad: REDWOOD POINT Longitude: 122° 12.6' W (-122.21000)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 4523 B 2015
DESIGNATION: 941 4523 B
MONUMENTATION: Tidal Station disk VM#: 21819
AGENCY: National Ocean Service (NOS) IDB PID:
SETTING CLASSIFICATION: Power pole foundation OPUS PID:
LATITUDE: 37° 30.4' N ( 37.50672) LONGITUDE: 122° 12.6' W (-122.20917)
The bench mark is a NOS disk set in the SE corner of the concrete foundation of
a large metal power pole, # 0-8 40871287 between frontage road and seaport
boulevard, S of the entrance to port of redwood city, located 5.85 m (19.2 ft) W
of centerline of Frontage Road, 1.08 m (3.5 ft) N of S side of foundation, 0.75
m (2.5 ft) SE of power pole.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 7
Station ID: 9414523 PUBLICATION DATE: 06/22/2020
Name: REDWOOD CITY, WHARF 5, S. F. BAY
CA
NOAA Chart: 18651 Latitude: 37° 30.4' N ( 37.50670)
USGS Quad: REDWOOD POINT Longitude: 122° 12.6' W (-122.21000)
T I D A L D A T U M S
Tidal datums at REDWOOD CITY, WHARF 5, S. F. BAY based on:
LENGTH OF SERIES: 21 YEARS
TIME PERIOD: October 1997 - September 2018
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 9414750 ALAMEDA, SAN FRANCISCO BAY
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
HIGHEST OBSERVED WATER LEVEL (12/03/1983) = 3.289
MEAN HIGHER HIGH WATER MHHW = 2.500
MEAN HIGH WATER MHW = 2.307
MEAN SEA LEVEL MSL = 1.342
MEAN TIDE LEVEL MTL = 1.336
MEAN LOW WATER MLW = 0.365
North American Vertical Datum NAVD88 = 0.360
MEAN LOWER LOW WATER MLLW = 0.000
LOWEST OBSERVED WATER LEVEL (01/11/2009) = -0.848
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
4508 A 1997 2.787 0.480
4508 B 1997 2.048 -0.259
4508 C 1997 3.882 1.575
WHARF 4 1985 4.618 2.311
4508 T 1998 4.109 1.802
4508 U 1998 3.535 1.228
4523 A 2009 2.328 0.021
4523 B 2015 2.256 -0.051
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 7 of 7
Station ID: 9414523 PUBLICATION DATE: 06/22/2020
Name: REDWOOD CITY, WHARF 5, S. F. BAY
CA
NOAA Chart: 18651 Latitude: 37° 30.4' N ( 37.50670)
USGS Quad: REDWOOD POINT Longitude: 122° 12.6' W (-122.21000)
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.