U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 4
PUBLICATION DATE: 02/10/1988
Station ID: 8720001 SUPERCEDED DATE: 04/21/2003
Name: KINGS FERRY, ST. MARYS RIVER
FLORIDA
NOAA Chart: Latitude: 30° 47.2' N
USGS Quad: KINGS FERRY Longitude: 81° 50.4' W
To reach the tidal bench marks from the intersection of U.S. Highway 17 and
County Road C-108 north of Yulee, proceed west on County Road C-108 for 9.6
miles (15.4 km) to County Road C-121A, then north on County Road C-121A for 2.95
miles (4.75 km) to the end of the pavement, continue north on the dirt road for
3.65 miles (5.87 km) to a private drive leading north, turn left and go north to
the end of the drive. The bench marks are located in the area along the dirt
road and along County Road C-115A. The tide gage and staff were located on the
NW corner of the dock at the Keene residence, 39 feet (12 m) north of the south
shore of St. Marys River.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 0001 B 1977
MONUMENTATION: Survey Disk VM#: 4961
AGENCY: PID#: BC2413
SETTING CLASSIFICATION: Copper-clad Steel Rod
The bench mark is 640 feet (195 m) SSW of Bench Mark 0001 A 1977, 280 feet (85
m) SE of the SE corner of the Kings Ferry Grocery Store, 17.5 feet (5.3 m) south
of the dirt drive that runs east to west between County Roads C-121A and C-115A
and 0.2 foot (0.1 m) north of a witness post. The bench mark is 0.2 foot (0.1
m) below ground level, crimped to a copper-clad steel rod driven 28 feet (9 m)
to refusal and encased in a PVC pipe and concrete kickblock.
BENCH MARK STAMPING: 105 CMP 1970
MONUMENTATION: Survey DiskA VM#: 4958
AGENCY: PID#: BC2410
SETTING CLASSIFICATION: Concrete Monument
The bench mark is set flush in the top of a concrete monument 1.25 miles (2.01
km) south of the north end of County Road C-115A, 0.9 mile (1.4 km) south of
Bench Mark 106 CMP 1970, 62.4 feet (19.0 m) ESE of the centerline of County Road
C-115A 49 feet (15 m) east of Charles Wittaker's mailbox and 13.6 feet (4.1 m)
SSW of a dirt drive leading east.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 4
PUBLICATION DATE: 02/10/1988
Station ID: 8720001 SUPERCEDED DATE: 04/21/2003
Name: KINGS FERRY, ST. MARYS RIVER
FLORIDA
NOAA Chart: Latitude: 30° 47.2' N
USGS Quad: KINGS FERRY Longitude: 81° 50.4' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 106 CMP 1970
MONUMENTATION: Survey Disk VM#: 4959
AGENCY: PID#: BC2411
SETTING CLASSIFICATION: Concrete Monument
The bench mark is set flush in the top of a concrete monument 0.40 mile (0.6 km)
south of the north end of County Road C-115A, 0.2 mile (0.3 km) south of Bench
Mark 0001 C 1977 56.4 feet (17.2 m) west of the centerline of County Road C-115A
and 1.5 feet (0.5 m) NW of a witness post.
BENCH MARK STAMPING: 0001 A 1977
MONUMENTATION: Survey Disk VM#: 4960
AGENCY: PID#: BC2414
SETTING CLASSIFICATION: Concrete Pad
The bench mark is set flush in a 18 x 16 foot (5x5 m) concrete pad, 12.6 feet
(3.8 m) NW of the NW corner of the white 2-story house (Keene residence), 20
feet (6 m) above the southern shore of St. Marys River, 12.5 feet (3.8 m) west
of the east face of the pad, and 3 feet (1 m) north of the south face of the
concrete pad.
BENCH MARK STAMPING: 0001 C 1977
MONUMENTATION: Survey Disk VM#: 4962
AGENCY: PID#: BC2412
SETTING CLASSIFICATION: Copper-clad Steel Rod
The bench mark is 0.2 mile (0.3 km) south of the north end of County Road
C-115A, 40.4 feet (12.3 m) east of the centerline of County Road C-115A, 6.3
feet (1.9 m) north of a power pole and 0.3 foot (0.1 m) west of a witness post.
The bench mark is 0.1 foot (0.03 m) below ground, crimped to a copper-clad steel
rod driven 22 feet (7 m) to refusal, and encased in a PVC pipe and concrete
kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 4
PUBLICATION DATE: 02/10/1988
Station ID: 8720001 SUPERCEDED DATE: 04/21/2003
Name: KINGS FERRY, ST. MARYS RIVER
FLORIDA
NOAA Chart: Latitude: 30° 47.2' N
USGS Quad: KINGS FERRY Longitude: 81° 50.4' W
T I D A L D A T U M S
Tidal datums at KINGS FERRY, ST. MARYS RIVER based on:
LENGTH OF SERIES: 4 MONTHS
TIME PERIOD: DECEMBER 1977-MARCH 1978
TIDAL EPOCH: 1960-1978
CONTROL TIDE STATION: 8720030 FERNANDINA
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in FEET:
HIGHEST OBSERVED WATER LEVEL (12/12/1977) = 3.63
MEAN HIGHER HIGH WATER MHHW = 3.12
MEAN HIGH WATER MHW = 2.97
MEAN TIDE LEVEL MTL = 1.60
MEAN LOW WATER MLW = 0.23
MEAN LOWER LOW WATER MLLW = 0.00
LOWEST OBSERVED WATER LEVEL (01/09/1978) = -2.73
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In FEET above:
Stamping or Designation MLLW MHW
0001 B 1977 19.02 16.05
105 CMP 1970 20.14 17.17
106 CMP 1970 13.80 10.83
0001 A 1977 11.75 8.78
0001 C 1977 19.60 16.63
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 4
PUBLICATION DATE: 02/10/1988
Station ID: 8720001 SUPERCEDED DATE: 04/21/2003
Name: KINGS FERRY, ST. MARYS RIVER
FLORIDA
NOAA Chart: Latitude: 30° 47.2' N
USGS Quad: KINGS FERRY Longitude: 81° 50.4' W
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 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.