U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 6
Station ID: 8720653 PUBLICATION DATE: 01/23/2004
Name: PALMETTO BLUFF, ST. JOHNS RIVER
FL
NOAA Chart: 11492 Latitude: 29° 45.8' N ( 29.76330)
USGS Quad: RIVERDALE Longitude: 81° 33.7' W ( -81.56170)
To reach the tidal bench marks from the intersection of Palmetto Bluff Road
(State Road 209) and the Seaboard Coastline Railroad in Bostwick, proceed east
on Palmetto Bluff Road for 4.4 km (2.8 mi) to Cedar Creek Road, then turn left
and proceed north on Cedar Creek Road for 0.24 m (0.15 mi) to the dirt road
leading east to the residence of Mr. Brice E. Bell. The bench marks are in the
area around the residence, and in the vicinity of the intersection of Palmetto
Bluff Road and Cedar Creek Road. The gage and staff were located on a private
dock in rear of the Bell residence.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: NO 1 1934
DESIGNATION: 872 0653 TIDAL 1
MONUMENTATION: Tidal Station disk VM#: 5224
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: AQ2595
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 29° 45.7' N ( 29.76194) LONGITUDE: 81° 33.7' W ( -81.56222)
The primary bench mark is a disk set in the top of a concrete monument at the
east end of Palmetto Bluff Road, 31.24 m (102.5 ft) south of an Artesian well on
the NW side of the circular end of the road, 8.78 m (28.8 ft) east of the NE
corner of a dilapidated shed, 1.22 m (4.0 ft) west of the top of the river bank,
and 0.12 m (0.4 ft) above ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 6
Station ID: 8720653 PUBLICATION DATE: 01/23/2004
Name: PALMETTO BLUFF, ST. JOHNS RIVER
FL
NOAA Chart: 11492 Latitude: 29° 45.8' N ( 29.76330)
USGS Quad: RIVERDALE Longitude: 81° 33.7' W ( -81.56170)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: NO 3 1934
DESIGNATION: 872 0653 TIDAL 3
MONUMENTATION: Tidal Station disk VM#: 5225
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: AQ2594
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 29° 45.7' N ( 29.76250) LONGITUDE: 81° 33.8' W ( -81.56250)
The bench mark is a disk set in a concrete monument near the east end of
Palmetto Bluff Road, 83.67 m (274.5 ft) SE of bench mark NO 2 1934 Reset 1962,
20.42 m (67.0 ft) SE of power pole with a transformer, 12.19 m (40.0 ft) north
of the centerline of Palmetto Bluff Road, 1.43 m (4.7 ft) NE of a fence, and
0.15 m (0.5 ft) above ground level.
BENCH MARK STAMPING: NO 2 1934 RESET 1962
DESIGNATION: 872 0653 TIDAL 2 RESET
MONUMENTATION: Bench Mark disk VM#: 5226
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: AQ2597
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 29° 45.8' N ( 29.76306) LONGITUDE: 81° 33.8' W ( -81.56250)
The bench mark is a disk set in top of a concrete monument, 23.32 m (76.5 ft)
north of and across the road from bench mark NO 4 1962, 21.34 m (70.0 ft) NE of
the centerline intersection of Palmetto Bluff Road and Cedar Creek Road, 6 m (19
ft) NW of bench mark 0653 B, and 0.1 m (0.3 ft) above ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 6
Station ID: 8720653 PUBLICATION DATE: 01/23/2004
Name: PALMETTO BLUFF, ST. JOHNS RIVER
FL
NOAA Chart: 11492 Latitude: 29° 45.8' N ( 29.76330)
USGS Quad: RIVERDALE Longitude: 81° 33.7' W ( -81.56170)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: NO 4 1962
DESIGNATION: 872 0653 TIDAL 4
MONUMENTATION: Bench Mark disk VM#: 5227
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: AQ2592
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 29° 45.8' N ( 29.76306) LONGITUDE: 81° 33.8' W ( -81.56250)
The bench mark is a disk set in a concrete monument at the NW corner of a fence
at the intersection of Cedar Point Road and Palmetto Bluff Road, 10.76 m (35.3
ft) SW of the centerline of Palmetto Bluff Road, 0.70 m (2.3 ft) SW of bench
mark Y Y2 0653 C 66 66 PALMETTO, and at ground level.
BENCH MARK STAMPING: 0653 A 1978
DESIGNATION: 872 0653 A TIDAL
MONUMENTATION: Tidal Station disk VM#: 5228
AGENCY: National Ocean Survey (NOS) IDB PID#: AQ2598
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 29° 45.9' N ( 29.76472) LONGITUDE: 81° 33.8' W ( -81.56250)
The bench mark is a disk set flush in a concrete monument, 183 m (600 ft) north
of bench mark NO 2 1934 Reset 1962, 9.30 m (30.5 ft) east of the centerline of
Cedar Creek Road, 7 m (24 ft) north of the centerline of the dirt road leading
east of the Brice E. Bell residence, 0.49 m (1.6 ft) west of a power pole with a
witness post at the NW corner of the fence line surrounding the Bell residence,
and 0.1 m (0.2 ft) below ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 6
Station ID: 8720653 PUBLICATION DATE: 01/23/2004
Name: PALMETTO BLUFF, ST. JOHNS RIVER
FL
NOAA Chart: 11492 Latitude: 29° 45.8' N ( 29.76330)
USGS Quad: RIVERDALE Longitude: 81° 33.7' W ( -81.56170)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 0653 B
DESIGNATION: 872 0653 B TIDAL
MONUMENTATION: Survey disk VM#: 5229
AGENCY: Florida Department of Transportation
(FLDT) IDB PID#: AQ2596
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 29° 45.8' N ( 29.76306) LONGITUDE: 81° 33.8' W ( -81.56250)
The bench mark is a disk set flush in a concrete monument, 21 m (69 ft) ENE of
the intersection of Palmetto Bluff Road and Cedar Creek Road, 10 m (32 ft) north
of the ceterline of Palmetto Bluff Road, 6 m (19 ft) SE of bench mark NO 2 1934
Rest 1962, and 0.4 m (1.4 ft) above ground level.
BENCH MARK STAMPING: Y Y2 0653 C 66 66 PALMETTO
DESIGNATION: 872 0653 TIDAL CY 2
MONUMENTATION: Survey disk VM#: 5230
AGENCY: Florida Department of Transportation
(FLDT) IDB PID#: AQ2593
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 29° 45.8' N ( 29.76306) LONGITUDE: 81° 33.8' W ( -81.56250)
The bench mark is a disk set flush in a concrete monument, 21 m (70 ft) SE of
the intersection of Palmetto Bluff Road and Cedar Creek Road, 16.55 m (54.3 ft)
SE of the Centerline of Cedar Creek Road, 10 m (34 ft) east of the largest oak
tree in the area, 9.63 m (31.6 ft) SW of the centerline of Palmetto Bluff Road,
0.73 m (2.4 ft) NE of bench mark NO 4 1962, 0.3 m (1 ft) north of a fence
corner, and 0.06 m (0.2 ft) above ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 6
Station ID: 8720653 PUBLICATION DATE: 01/23/2004
Name: PALMETTO BLUFF, ST. JOHNS RIVER
FL
NOAA Chart: 11492 Latitude: 29° 45.8' N ( 29.76330)
USGS Quad: RIVERDALE Longitude: 81° 33.7' W ( -81.56170)
T I D A L D A T U M S
Tidal datums at PALMETTO BLUFF, ST. JOHNS RIVER based on:
LENGTH OF SERIES: 7 MONTHS
TIME PERIOD: September 1978 - March 1979
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8720496 GREEN COVE SPRINGS, ST. JOHNS R.
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 0.362
MEAN HIGH WATER MHW = 0.335
North American Vertical Datum NAVD88 = 0.189
MEAN TIDE LEVEL MTL = 0.175
MEAN SEA LEVEL MSL = 0.170
MEAN LOW WATER MLW = 0.015
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
NO 1 1934 2.032 1.697
NO 3 1934 1.985 1.650
NO 2 1934 RESET 1962 2.409 2.074
NO 4 1962 2.343 2.008
0653 A 1978 1.708 1.373
0653 B 2.520 2.185
Y Y2 0653 C 66 66 PALMETTO 2.409 2.074
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 6
Station ID: 8720653 PUBLICATION DATE: 01/23/2004
Name: PALMETTO BLUFF, ST. JOHNS RIVER
FL
NOAA Chart: 11492 Latitude: 29° 45.8' N ( 29.76330)
USGS Quad: RIVERDALE Longitude: 81° 33.7' W ( -81.56170)
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.