U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
Station ID: 8729943 PUBLICATION DATE: 05/12/2004
Name: HURST HAMMOCK, PERDIDO RIVER
FL
NOAA Chart: 11382 Latitude: 30° 27.5' N ( 30.45830)
USGS Quad: LILLIAN Longitude: 87° 24.5' W ( -87.40830)
To reach the tidal bench marks from the intersection of U.S. Alt. Highway 90 and
U.S. Highway 90 west of Pensacola, proceed SE on U.S. Highway 90 for 2.6 km (1.6
mi) to County Road C-99, then turn right and proceed south on County Road C-99
to its end at Hurst Hammock and a east-west running dirt drive, then proceed 0.2
km (0.1 mi) east on the dirt drive to the last house on the south side of the
drive. The bench marks are along County Road C-99 and the dirt drive. The tide
gage and staff were located on a dock behind the private residence.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 9943 A 1977
DESIGNATION: 872 9943 A TIDAL
MONUMENTATION: Tidal Station disk VM#: 10312
AGENCY: National Ocean Survey (NOS) IDB PID#: BG4597
SETTING CLASSIFICATION: Galvanized steel rod OPUS PID#: BG4597
LATITUDE: 30° 27.6' N ( 30.46000) LONGITUDE: 87° 24.5' W ( -87.40830)
The primary bench mark is a disk located 91 m (300 ft) east of bench mark 9943 B
1977, 6.0 m (19.8 ft) south of the dirt drive, 4.24 m (13.9 ft) east of the
centerline of the dirt driveway to the next to the last house, and 1.13 m (3.7
ft) east of the NE corner of the fence around the property. The bench mark is
set 12 cm (0.4 ft) below ground level, crimped to the top of a galvanized steel
rod driven 12.2 m (40 ft), and encased in a PVC pipe and concrete kickblock.
NOTE: Mark not found in 2003 by US Power Squadron.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
Station ID: 8729943 PUBLICATION DATE: 05/12/2004
Name: HURST HAMMOCK, PERDIDO RIVER
FL
NOAA Chart: 11382 Latitude: 30° 27.5' N ( 30.45830)
USGS Quad: LILLIAN Longitude: 87° 24.5' W ( -87.40830)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 9943 B 1977
DESIGNATION: 872 9943 B TIDAL
MONUMENTATION: Tidal Station disk VM#: 10313
AGENCY: National Ocean Survey (NOS) IDB PID#: BG4596
SETTING CLASSIFICATION: Galvanized steel rod OPUS PID#: BG4596
LATITUDE: 30° 27.6' N ( 30.46000) LONGITUDE: 87° 24.5' W ( -87.40830)
The bench mark is a disk located 91 m (300 ft) west of bench mark 9943 A 1977,
80 m (263 ft) east of bench mark 9943 C 1977, 4.51 m (14.8 ft) south of the dirt
drive, 1.65 m (5.4 ft) NE of the NW corner of the fence around the next to last
house along the drive, and 0.88 m (2.9 ft) east of a powerline pole with a
witness sign. The bench mark is set 12 cm (0.4 ft) below ground level, crimped
to the top of a galvanized steel rod driven 12.2 m (40 ft), and encased in a PVC
pipe and concrete kickblock. NOTE: Mark not found in 2003 by US Power Squadron.
BENCH MARK STAMPING: 9943 C 1977
DESIGNATION: 872 9943 C TIDAL
MONUMENTATION: Tidal Station disk VM#: 10314
AGENCY: National Ocean Survey (NOS) IDB PID#: BG4595
SETTING CLASSIFICATION: Galvanized steel rod OPUS PID:
LATITUDE: 30° 27.6' N ( 30.46000) LONGITUDE: 87° 24.6' W ( -87.41000)
The bench mark is a disk located 80 m (262 ft) SSE of bench mark 9943 D 1977,
7.44 m (24.4 ft) west of the centerline of the dirt drive, and 1.55 m (5.1 ft)
north of powerline pole #08340-54257 with a witness sign. The bench mark is set
9 cm (0.3 ft) below ground level, crimped to the top of a galvanized steel rod
driven 12.2 m (40 ft), 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 5
Station ID: 8729943 PUBLICATION DATE: 05/12/2004
Name: HURST HAMMOCK, PERDIDO RIVER
FL
NOAA Chart: 11382 Latitude: 30° 27.5' N ( 30.45830)
USGS Quad: LILLIAN Longitude: 87° 24.5' W ( -87.40830)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 9943 D 1977
DESIGNATION: 872 9943 D TIDAL
MONUMENTATION: Tidal Station disk VM#: 10315
AGENCY: National Ocean Survey (NOS) IDB PID#: BG4594
SETTING CLASSIFICATION: Galvanized steel rod OPUS PID:
LATITUDE: 30° 27.6' N ( 30.46000) LONGITUDE: 87° 24.6' W ( -87.41000)
The bench mark is a disk located 14.17 m (46.5 ft) SSE of the SE corner of the
last residence on the west side of County Road C-99 (before the end of the
pavement), 11 m (35 ft) north of the north bank of a canal, 10 m (32 ft) west of
the centerline of the road, and 1.5 m (5.0 ft) south of powerline pole
#83365-54277 with a witness sign. The bench mark is set level with the ground,
crimped to the top of a galvanized steel rod driven 12.2 m (40 ft), and encased
in a PVC pipe and concrete kickblock.
BENCH MARK STAMPING: 9943 E 1977
DESIGNATION: 872 9943 E TIDAL
MONUMENTATION: Tidal Station disk VM#: 10316
AGENCY: National Ocean Survey (NOS) IDB PID#: BG4593
SETTING CLASSIFICATION: Galvanized steel rod OPUS PID:
LATITUDE: 30° 27.7' N ( 30.46170) LONGITUDE: 87° 24.6' W ( -87.41000)
The bench mark is a disk located 116 m (380 ft) north of bench mark 9943 D 1977,
14.30 m (46.9 ft) east of the SE corner of a fenced residence, 8.72 m (28.6 ft)
west of the centerline of County Road C-99, and 2.62 m (8.6 ft) north of a
lighted powerline pole with a witness sign. The bench mark is set 9 cm (0.3 ft)
below ground level, crimped to a galvanized steel rod driven 12.2 m (40 ft), and
encased in a PVC pipe and concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
Station ID: 8729943 PUBLICATION DATE: 05/12/2004
Name: HURST HAMMOCK, PERDIDO RIVER
FL
NOAA Chart: 11382 Latitude: 30° 27.5' N ( 30.45830)
USGS Quad: LILLIAN Longitude: 87° 24.5' W ( -87.40830)
T I D A L D A T U M S
Tidal datums at HURST HAMMOCK, PERDIDO RIVER based on:
LENGTH OF SERIES: 1 MONTH
TIME PERIOD: July 1977 - July 1977
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8729962 PERDIDO BAY
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 0.240
MEAN HIGH WATER MHW = 0.232
MEAN TIDE LEVEL MTL = 0.125
MEAN SEA LEVEL MSL = 0.113
MEAN LOW WATER MLW = 0.018
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum NAVD88 = -0.014
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
9943 A 1977 1.296 1.064
9943 B 1977 2.475 2.243
9943 C 1977 3.393 3.161
9943 D 1977 0.974 0.742
9943 E 1977 1.095 0.863
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
Station ID: 8729943 PUBLICATION DATE: 05/12/2004
Name: HURST HAMMOCK, PERDIDO RIVER
FL
NOAA Chart: 11382 Latitude: 30° 27.5' N ( 30.45830)
USGS Quad: LILLIAN Longitude: 87° 24.5' W ( -87.40830)
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.