U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 4
Station ID: 9413643 PUBLICATION DATE: 05/22/2013
Name: TIDAL CREEK, ELKHORN SLOUGH
CA
NOAA Chart: 18680 Latitude: 36° 50.0' N ( 36.83333)
USGS Quad: PRUNEDALE Longitude: 121° 44.7' W (-121.74500)
Take Highway 1 to Moss Landing at the power plant, turn east onto Dolan Road for
3.5 miles, make a left on Elkhorn Road, proceed about 5 miles to Kirby Park
entrance on the left. Proceed to travel via boat to GPS coordinates. Proceed
south from boat landing. Head east into the largest tidal creek south of
landing on west side of slough approximately 0.5 miles and follow creek to the
tide station platform made of wood.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 3643 A 2008
DESIGNATION: 941 3643 A
MONUMENTATION: Tidal Station disk VM#: 18603
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 36° 50.0' N ( 36.83330) LONGITUDE: 121° 44.8' W (-121.74700)
The bench mark is located in Elkhorn Slough at Tidal Creek SW of Moss landing,
8.29 m (27.2 ft) south of a cluster of California Live Oaks, 5.00 m (16.4 ft)
west of the ecotone, and 0.67m (2.2 ft) east of a witness post sign posted on a
sign posted "Private licensed pheasant club, Elkhorn Slough, David Packard. The
bench mark is crimped to a stainless steel rod is driven 10.1 m (33 ft) to
refusal and encased in a 6" PVC pipe with lid cover.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 4
Station ID: 9413643 PUBLICATION DATE: 05/22/2013
Name: TIDAL CREEK, ELKHORN SLOUGH
CA
NOAA Chart: 18680 Latitude: 36° 50.0' N ( 36.83333)
USGS Quad: PRUNEDALE Longitude: 121° 44.7' W (-121.74500)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 3643 B 2008
DESIGNATION: 941 3643 B
MONUMENTATION: Tidal Station disk VM#: 18604
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 36° 50.0' N ( 36.83330) LONGITUDE: 121° 44.8' W (-121.74700)
The bench mark is located in Elkhorn Slough at Tidal Creek SW of Moss landing,
60.0 m (197 ft) SW of the Tidal Creek tide station, 30.00 m (98.4 ft) NE of the
SW ecotone, and 4.0 m (13 ft) NW of the slough creek edge. The bench mark is
crimped to a stainless steel rod driven 12.6 m (41 ft) to refusal and encased in
a PVC pipe with a cover lid.
BENCH MARK STAMPING: 3643 C 2008
DESIGNATION: 941 3643 C
MONUMENTATION: Tidal Station disk VM#: 18605
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 36° 50.0' N ( 36.83330) LONGITUDE: 121° 44.7' W (-121.74500)
The bench mark is located in Elkhorn Slough at Tidal Creek SW of Moss landing,
28.50 m (93.5 ft) south of a small wooden boat landing, 19.70 m (64.6 ft) north
of a large group of California Live Oaks, and 15.70 m (51.5 ft) NW of the slough
creek edge. The bench mark is crimped to a stainless steel rod driven 9.4 m
(30.7 ft) to refusal and encased in a PVC pipe with a cover lid.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 4
Station ID: 9413643 PUBLICATION DATE: 05/22/2013
Name: TIDAL CREEK, ELKHORN SLOUGH
CA
NOAA Chart: 18680 Latitude: 36° 50.0' N ( 36.83333)
USGS Quad: PRUNEDALE Longitude: 121° 44.7' W (-121.74500)
T I D A L D A T U M S
Tidal datums at TIDAL CREEK, ELKHORN SLOUGH based on:
LENGTH OF SERIES: 3 MONTHS
TIME PERIOD: July 2008 - September 2008
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 9413450 MONTEREY, MONTEREY HARBOR
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 1.633
MEAN HIGH WATER MHW = 1.417
MEAN SEA LEVEL MSL = 0.874
MEAN TIDE LEVEL MTL = 0.871
MEAN LOW WATER MLW = 0.325
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
3643 A 2008 2.344 0.927
3643 B 2008 1.413 -0.004
3643 C 2008 2.394 0.976
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 4
Station ID: 9413643 PUBLICATION DATE: 05/22/2013
Name: TIDAL CREEK, ELKHORN SLOUGH
CA
NOAA Chart: 18680 Latitude: 36° 50.0' N ( 36.83333)
USGS Quad: PRUNEDALE Longitude: 121° 44.7' W (-121.74500)
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.