U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
Station ID: 8727061 PUBLICATION DATE: 04/29/2004
Name: HUDSON, HUDSON CREEK
FL
NOAA Chart: 11409 Latitude: 28° 21.7' N ( 28.36170)
USGS Quad: PORT RICHEY Longitude: 82° 42.6' W ( -82.71000)
To reach the tidal bench marks from the Hudson Post Office proceed 0.5 km (0.3
mi) SW on U.S. Highway 19 to its intersection with Clark Street, then turn right
and proceed 1.6 km (1 mi) west on Clark Street to the Gulfview Marina. The
bench marks are located near the marina. The tide gage and staff were located
on a seawall behind a mobile home.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 7061 B 1978
DESIGNATION: 872 7061 B TIDAL
MONUMENTATION: Tidal Station disk VM#: 7722
AGENCY: National Ocean Survey (NOS) IDB PID#: AL7414
SETTING CLASSIFICATION: Copper-clad steel rod OPUS PID:
LATITUDE: 28° 21.6' N ( 28.36000) LONGITUDE: 82° 42.5' W ( -82.70830)
The primary bench mark is a disk located 79 m (260 ft) north of bench mark 7061
A 1978, 32 m (104 ft) SW of the SW corner of the Sunset Room Motel, 16 m (51 ft)
ESE of the SE corner of a stucco storage building, 7.77 m (25.5 ft) west of the
centerline of the road, 1.5 m (5 ft) south of a guy wire for a brace pole, 1.37
m (4.5 ft) west of a utility line brace pole, and 0.3 m (1 ft) NE of a witness
post. The bench mark is set 0.03 m (0.1 ft) above ground level, crimped to the
top of a copper-clad steel rod driven 9.4 m (31 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 5
Station ID: 8727061 PUBLICATION DATE: 04/29/2004
Name: HUDSON, HUDSON CREEK
FL
NOAA Chart: 11409 Latitude: 28° 21.7' N ( 28.36170)
USGS Quad: PORT RICHEY Longitude: 82° 42.6' W ( -82.71000)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 7061 A 1978
DESIGNATION: 872 7061 A TIDAL
MONUMENTATION: Tidal Station disk VM#: 7721
AGENCY: National Ocean Survey (NOS) IDB PID#: AL7415
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 28° 21.6' N ( 28.36000) LONGITUDE: 82° 42.5' W ( -82.70830)
The bench mark is a disk set in a concrete monument, 80 m (262 ft) south of the
edge of Clark Street, 35 m (115 ft) north of a seawall, 24.54 m (80.5 ft) NE of
the north corner of a mobile home, 20.33 m (66.7 ft) WSW of the SW corner of the
Gulfview Marina office, 1.07 m (3.5 ft) north of a utility pole with a witness
sign attached, and 3 cm (0.1 ft) above ground level.
BENCH MARK STAMPING: 7061 C 1978
DESIGNATION: 872 7061 C TIDAL
MONUMENTATION: Tidal Station disk VM#: 7723
AGENCY: National Ocean Survey (NOS) IDB PID#: AL7413
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 28° 21.6' N ( 28.36000) LONGITUDE: 82° 42.4' W ( -82.70670)
The bench mark is a disk set in a concrete monument, 44 m (143 ft) east of the
east corner of the Sunset Room Motel, 21 m (70 feet) SW of the edge of a canal,
5.33 m (17.5 ft) north of the centerline of Clark Street, 0.49 m (1.6 ft) SE of
a utility pole with a witness sign attached, and 6 cm (0.2 ft) below ground
level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
Station ID: 8727061 PUBLICATION DATE: 04/29/2004
Name: HUDSON, HUDSON CREEK
FL
NOAA Chart: 11409 Latitude: 28° 21.7' N ( 28.36170)
USGS Quad: PORT RICHEY Longitude: 82° 42.6' W ( -82.71000)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 7061 D 1978
DESIGNATION: 872 7061 D TIDAL
MONUMENTATION: Tidal Station disk VM#: 7724
AGENCY: National Ocean Survey (NOS) IDB PID#: AL7412
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 28° 21.6' N ( 28.36000) LONGITUDE: 82° 42.3' W ( -82.70500)
The bench mark is a disk set in a concrete monument, 114 m (373 ft) ESE of bench
mark 7061 C 1978, 49.83 m (163.5 ft) NW of the NW corner of a bait and tackle
shop, 29 m (96 ft) SW of the west corner of the house at 204 Clark Street, 8.44
m (27.7 ft) SW of the centerline of Clark Street, 0.52 m (1.7 ft) NE of a
witness post, and 6 cm (0.2 ft) below ground level.
BENCH MARK STAMPING: 7061 E 1978
DESIGNATION: 872 7061 E TIDAL
MONUMENTATION: Tidal Station disk VM#: 7725
AGENCY: National Ocean Survey (NOS) IDB PID#: AL7411
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 28° 21.6' N ( 28.36000) LONGITUDE: 82° 42.3' W ( -82.70500)
The bench mark is a disk set in a concrete monument, 200 m (655 ft) east of
bench mark 7061 D 1978, 38 m (125 ft) north and across the street from the NW
corner of a partially bricked house, 10 m (33 ft) SE of the SW corner of the
office of Villa Del Mar Apartments, 9.42 m (30.9 ft) SW of the SE corner of the
apartment office, 1.31 m (4.3 ft) ENE of a utility pole with a witness sign
attached, 0.3 m (1 ft) north of the south edge of a rock garden, and 6 cm (0.2
ft) below ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
Station ID: 8727061 PUBLICATION DATE: 04/29/2004
Name: HUDSON, HUDSON CREEK
FL
NOAA Chart: 11409 Latitude: 28° 21.7' N ( 28.36170)
USGS Quad: PORT RICHEY Longitude: 82° 42.6' W ( -82.71000)
T I D A L D A T U M S
Tidal datums at HUDSON, HUDSON CREEK based on:
LENGTH OF SERIES: 3 MONTHS
TIME PERIOD: September 1978 - November 1978
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8726724 CLEARWATER BEACH, GULF OF MEXICO
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 1.019
MEAN HIGH WATER MHW = 0.910
North American Vertical Datum NAVD88 = 0.670
MEAN SEA LEVEL MSL = 0.546
MEAN TIDE LEVEL MTL = 0.532
MEAN LOW WATER MLW = 0.154
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
7061 B 1978 1.943 1.033
7061 A 1978 1.700 0.790
7061 C 1978 1.953 1.043
7061 D 1978 1.646 0.736
7061 E 1978 1.951 1.041
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
Station ID: 8727061 PUBLICATION DATE: 04/29/2004
Name: HUDSON, HUDSON CREEK
FL
NOAA Chart: 11409 Latitude: 28° 21.7' N ( 28.36170)
USGS Quad: PORT RICHEY Longitude: 82° 42.6' W ( -82.71000)
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.