U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 8
Station ID: 8729747 PUBLICATION DATE: 02/05/2004
Name: SHIELD POINT, BLACKWATER RIVER
FL
NOAA Chart: 11382 Latitude: 30° 34.9' N ( 30.58170)
USGS Quad: MILTON SOUTH Longitude: 87° 0.9' W ( -87.01500)
To reach the tidal bench marks from the Bagdad Schoolhouse in Bagdad, proceed
south on County Road C-191 for 1.3 km (0.8 mi) to County Road C-191C, then turn
left and proceed SE on County Road C-191C for 1.8 km (1.1 mi) to a private drive
for the Presley residence, 0.3 km (0.2 mi) SE of the overpass of Interstate
Highway 101, then turn left and proceed east along the drive for 0.8 km (0.5 mi)
to the Presley Residence. The bench marks are around the Presley residence and
at the overpass of Interstate Highway 10. The tide gage and staff were located
on a wooden dock behind the Presley residence.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: NO 2 1976
DESIGNATION: 872 9747 TIDAL 2
MONUMENTATION: Tidal Station disk VM#: 10220
AGENCY: National Ocean Survey (NOS) IDB PID#: BG4533
SETTING CLASSIFICATION: Copper-clad steel rod OPUS PID:
LATITUDE: 30° 34.6' N ( 30.57670) LONGITUDE: 87° 0.9' W ( -87.01500)
The primary bench mark is a disk located 25 m (82 ft) south of the SE corner of
the Presley residence, 12 m (39 ft) east of the centerline of the driveway
leading to the residence, and 1 m (3 ft) NNE of a power pole with a witness
sign. The bench mark is set 0.06 m (0.2 ft) below ground level, crimped to the
top of a copper-clad steel rod driven 7.3 m (24 ft) 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 2 of 8
Station ID: 8729747 PUBLICATION DATE: 02/05/2004
Name: SHIELD POINT, BLACKWATER RIVER
FL
NOAA Chart: 11382 Latitude: 30° 34.9' N ( 30.58170)
USGS Quad: MILTON SOUTH Longitude: 87° 0.9' W ( -87.01500)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: NO 1 1976
DESIGNATION: 872 9747 TIDAL 1
MONUMENTATION: Tidal Station disk VM#: 10219
AGENCY: National Ocean Survey (NOS) IDB PID#: BG4534
SETTING CLASSIFICATION: Copper-clad steel rod OPUS PID:
LATITUDE: 30° 34.9' N ( 30.58170) LONGITUDE: 87° 0.9' W ( -87.01500)
The bench mark is a disk located east of the Presley residence, 14.17 m (46.5
ft) east of the NE corner of the first residence south of the tide gage site,
11.73 m (38.5 ft) west of a barbed wire fence and 6.40 m (21.0 ft) south of an
enclosed concrete pad. The bench mark is at ground level, crimped to the top of
a copper-clad steel rod driven 7.0 m (23 ft) to refusal in the SW corner of the
a 3 m x 5 m (10 ft x 15 ft) concrete pad.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 8
Station ID: 8729747 PUBLICATION DATE: 02/05/2004
Name: SHIELD POINT, BLACKWATER RIVER
FL
NOAA Chart: 11382 Latitude: 30° 34.9' N ( 30.58170)
USGS Quad: MILTON SOUTH Longitude: 87° 0.9' W ( -87.01500)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: C165 RESET 1966
DESIGNATION: C 165 RESET
MONUMENTATION: Bench Mark disk VM#: 10221
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: BG0248
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 30° 34.6' N ( 30.57670) LONGITUDE: 87° 1.2' W ( -87.02000)
The bench mark is a disk set in the top of a concrete monument, near the County
Road C-191C overpass of Interstate Highway 10, 39 m (128 ft) NE of the
centerline of County Road C-191C, 37.34 m (122.5 ft) NNE of the NW end of the NE
concrete bannister of the bridge, 8.99 m (29.5 ft), ENE of a powerline pole,
0.55 m (1.8 ft) SW of a witness post, 0.37 m (1.2 ft) NW of the Interstate
Highway 10 right-of-way fence, and 0.3 m (1 ft) below ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 8
Station ID: 8729747 PUBLICATION DATE: 02/05/2004
Name: SHIELD POINT, BLACKWATER RIVER
FL
NOAA Chart: 11382 Latitude: 30° 34.9' N ( 30.58170)
USGS Quad: MILTON SOUTH Longitude: 87° 0.9' W ( -87.01500)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: I10 73 B 44 RM NO 2
DESIGNATION: I10 73 B44 RM 2
ALIAS: I 10 73 B 44
MONUMENTATION: Survey disk VM#: 10222
AGENCY: Florida Department of Transportation
(FLDT) IDB PID#: BG3157
SETTING CLASSIFICATION: Concrete curb OPUS PID:
LATITUDE: 30° 34.7' N ( 30.57830) LONGITUDE: 87° 1.2' W ( -87.02000)
The bench mark is a disk set flush in the curb in the SW corner of the Highway
191C overpass over Interstate 10, 3.84 m (12.6 ft) west of the centerline of the
Highway 191C overpass, 2 m (6 ft) NE of a witness sign, and 0.24 m (0.8 ft)
above ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 8
Station ID: 8729747 PUBLICATION DATE: 02/05/2004
Name: SHIELD POINT, BLACKWATER RIVER
FL
NOAA Chart: 11382 Latitude: 30° 34.9' N ( 30.58170)
USGS Quad: MILTON SOUTH Longitude: 87° 0.9' W ( -87.01500)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: V 301
DESIGNATION: V 301
MONUMENTATION: Survey disk VM#: 10223
AGENCY: Florida Department of Transportation
(FLDT) IDB PID#: BG0249
SETTING CLASSIFICATION: Concrete railing OPUS PID:
LATITUDE: 30° 34.7' N ( 30.57830) LONGITUDE: 87° 1.2' W ( -87.02000)
The bench mark is a disk set in the top of the concrete railing at the NW
abutment of the County Road C-191C overpass over Interstate Highway 10, 4.08 m
(13.4 ft) SW of the centerline of County Road C-191C, 2.04 m (6.7 ft) SE of the
NW end of the railing, 1.37 m (4.5 ft) NW of the west corner of the bridge, and
0.91 m (3.0 ft) above the level of the road.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 8
Station ID: 8729747 PUBLICATION DATE: 02/05/2004
Name: SHIELD POINT, BLACKWATER RIVER
FL
NOAA Chart: 11382 Latitude: 30° 34.9' N ( 30.58170)
USGS Quad: MILTON SOUTH Longitude: 87° 0.9' W ( -87.01500)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: W 301
DESIGNATION: W 301
MONUMENTATION: Survey disk VM#: 10224
AGENCY: Florida Department of Transportation
(FLDT) IDB PID#: BG0114
SETTING CLASSIFICATION: Concrete railing OPUS PID:
LATITUDE: 30° 34.7' N ( 30.57830) LONGITUDE: 87° 1.2' W ( -87.02000)
The bench mark is a disk set in the top of the concrete railing at the SE
abutment of the County Road C-191C overpass over Interstate Highway 10, 4.42 m
(14.5 ft) NE of the centerline of County Road C-191C, 1.43 m (4.7 ft) SE of the
east corner of the bridge, and 0.91 m (3.0 ft) above the level of the highway.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 7 of 8
Station ID: 8729747 PUBLICATION DATE: 02/05/2004
Name: SHIELD POINT, BLACKWATER RIVER
FL
NOAA Chart: 11382 Latitude: 30° 34.9' N ( 30.58170)
USGS Quad: MILTON SOUTH Longitude: 87° 0.9' W ( -87.01500)
T I D A L D A T U M S
Tidal datums at SHIELD POINT, BLACKWATER RIVER based on:
LENGTH OF SERIES: 10 MONTHS
TIME PERIOD: January 1993 - October 1993
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8729840 PENSACOLA, PENSACOLA BAY
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 0.484
MEAN HIGH WATER MHW = 0.453
MEAN TIDE LEVEL MTL = 0.241
MEAN SEA LEVEL MSL = 0.240
North American Vertical Datum NAVD88 = 0.144
MEAN LOW WATER MLW = 0.029
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 2 1976 4.598 4.145
NO 1 1976 4.906 4.453
C165 RESET 1966 4.987 4.534
I10 73 B 44 RM NO 2 13.416 12.963
V 301 14.045 13.592
W 301 14.269 13.816
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 8 of 8
Station ID: 8729747 PUBLICATION DATE: 02/05/2004
Name: SHIELD POINT, BLACKWATER RIVER
FL
NOAA Chart: 11382 Latitude: 30° 34.9' N ( 30.58170)
USGS Quad: MILTON SOUTH Longitude: 87° 0.9' W ( -87.01500)
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.