U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 4
Station ID: 8729179 PUBLICATION DATE: 04/29/2004
Name: CROOKED CREEK, WEST BAY
FL
NOAA Chart: 11389 Latitude: 30° 18.5' N ( 30.30830)
USGS Quad: WEST BAY Longitude: 85° 48.7' W ( -85.81170)
To reach the tidal bench marks from the intersection of County Road 388 and
State Highway 79 in West Bay, proceed 4.6 km (2.9 mi) east on County Road 388 to
the bridge over Crooked Creek. The bench marks are located along County Road
388. The tide gage and staff were located on a pier under the bridge.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 9179 B 1976
DESIGNATION: 872 9179 B TIDAL
MONUMENTATION: Tidal Station disk VM#: 10045
AGENCY: National Ocean Survey (NOS) IDB PID#: BE2983
SETTING CLASSIFICATION: Copper-clad steel rod OPUS PID:
LATITUDE: 30° 18.9' N ( 30.31500) LONGITUDE: 85° 48.6' W ( -85.81000)
The primary bench mark is a disk located 93 m (240 ft) ENE of bench mark 9179 A
76 RS 1977, 72 m (235 ft) NE of the NE end of the bridge over Crooked Creek,
13.47 m (44.2 ft) NW of the centerline of County Road 388, 26 m (85 ft) north of
the junction of a private road leading south, and 0.76 m (2.5 ft) SW of a
powerline anchor pole with a witness sign. The bench mark is set 0.21 m (0.7
ft) below ground level, crimped to the top of a copper clad steel rod driven
12.2 m (40 ft) to refusal, and encased in PVC pipe and concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 4
Station ID: 8729179 PUBLICATION DATE: 04/29/2004
Name: CROOKED CREEK, WEST BAY
FL
NOAA Chart: 11389 Latitude: 30° 18.5' N ( 30.30830)
USGS Quad: WEST BAY Longitude: 85° 48.7' W ( -85.81170)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 9179 C 1976
DESIGNATION: 872 9179 C TIDAL
MONUMENTATION: Tidal Station disk VM#: 10046
AGENCY: National Ocean Survey (NOS) IDB PID#: BE2982
SETTING CLASSIFICATION: Copper-clad steel rod OPUS PID:
LATITUDE: 30° 18.9' N ( 30.31500) LONGITUDE: 85° 48.6' W ( -85.81000)
The bench mark is a disk located 114 m (375 ft) SE of bench mark 9179 B 1976,
29.50 m (96.8 ft) SW of the junction of a dirt road leading south, 13.50 m (44.3
ft) SE of the centerline of County Road 388, and 0.30 m (1.0 ft) NW 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 copper-clad steel rod driven to refusal,
and encased in a PVC pipe and concrete kickblock.
BENCH MARK STAMPING: 9179 D 1976
DESIGNATION: 872 9179 D TIDAL
MONUMENTATION: Tidal Station disk VM#: 10047
AGENCY: National Ocean Survey (NOS) IDB PID#: BE2986
SETTING CLASSIFICATION: Copper-clad steel rod OPUS PID:
LATITUDE: 30° 18.7' N ( 30.31170) LONGITUDE: 85° 48.8' W ( -85.81330)
The bench mark is a disk located 122 m (400 ft) SW of the bridge over Crooked
Creek, 17.01 m (55.8 ft) SE of the centerline of County Road 388, 2.44 m (8.0
ft) SE of a powerline pole, and 0.30 m (1.0 ft) NW of a witness post. The bench
mark is set 0.18 m (0.6 ft) below ground level, crimped to the top of a
copper-clad steel rod driven 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
Station ID: 8729179 PUBLICATION DATE: 04/29/2004
Name: CROOKED CREEK, WEST BAY
FL
NOAA Chart: 11389 Latitude: 30° 18.5' N ( 30.30830)
USGS Quad: WEST BAY Longitude: 85° 48.7' W ( -85.81170)
T I D A L D A T U M S
Tidal datums at CROOKED CREEK, WEST BAY based on:
LENGTH OF SERIES: 3 MONTHS
TIME PERIOD: October 1976 - December 1976
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8729102 LYNN HAVEN, NORTH BAY
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 0.449
MEAN HIGH WATER MHW = 0.410
MEAN TIDE LEVEL MTL = 0.221
MEAN SEA LEVEL MSL = 0.220
North American Vertical Datum NAVD88 = 0.160
MEAN LOW WATER MLW = 0.031
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
9179 B 1976 4.042 3.632
9179 C 1976 5.158 4.748
9179 D 1976 4.471 4.062
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 4
Station ID: 8729179 PUBLICATION DATE: 04/29/2004
Name: CROOKED CREEK, WEST BAY
FL
NOAA Chart: 11389 Latitude: 30° 18.5' N ( 30.30830)
USGS Quad: WEST BAY Longitude: 85° 48.7' W ( -85.81170)
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.