U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
Station ID: 8726467 PUBLICATION DATE: 02/05/2004
Name: MARSH BRANCH, RUSKIN
FL
NOAA Chart: 11412 Latitude: 27° 43.1' N ( 27.71830)
USGS Quad: RUSKIN Longitude: 82° 27.2' W ( -82.45330)
To reach the tidal bench marks from the intersection of U.S. Highway 41 (Tamiami
Trail) and Shell Point Road in Ruskin, proceed west on Shell Point Road for 1.3
km (0.8 mi) to Yost Trailer Park. The bench marks are located in the area
around the trailer park. The tide gage and staff were located on a pier behind
the trailer park.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 6467 B 1977
DESIGNATION: 872 6467 B TIDAL
MONUMENTATION: Tidal Station disk VM#: 6508
AGENCY: National Ocean Survey (NOS) IDB PID#: AG7515
SETTING CLASSIFICATION: Concrete sea wall OPUS PID#: AG7515
LATITUDE: 27° 43.2' N ( 27.72000) LONGITUDE: 82° 26.9' W ( -82.44830)
The primary bench mark is a disk set in the top of a concrete sea wall, 10.52 m
(34.5 ft) south of the centerline of the paved road around the trailer park, 5 m
(18 ft) south of the north end of the boat ramp, and 0.18 m (0.6 ft) west of the
west edge of the boat ramp.
BENCH MARK STAMPING: 6467 C 1977
DESIGNATION: 872 6467 C TIDAL
MONUMENTATION: Tidal Station disk VM#: 6509
AGENCY: National Ocean Survey (NOS) IDB PID#: AG7514
SETTING CLASSIFICATION: Concrete boatlift platform OPUS PID#: AG7514
LATITUDE: 27° 43.2' N ( 27.72000) LONGITUDE: 82° 26.9' W ( -82.44830)
The bench mark is a disk set in the SE corner of the boatlift platform, 8.69 m
(28.5 ft) west of the centerline of the paved road around the trailer park, 2.53
m (8.3 ft) east of the center of the boatlift, and 0.3 m (1 ft) west of the east
side of the boatlift.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
Station ID: 8726467 PUBLICATION DATE: 02/05/2004
Name: MARSH BRANCH, RUSKIN
FL
NOAA Chart: 11412 Latitude: 27° 43.1' N ( 27.71830)
USGS Quad: RUSKIN Longitude: 82° 27.2' W ( -82.45330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 6467 E 1977
DESIGNATION: 872 6467 E TIDAL
MONUMENTATION: Tidal Station disk VM#: 6510
AGENCY: National Ocean Survey (NOS) IDB PID#: AG7513
SETTING CLASSIFICATION: Copper-clad steel rod OPUS PID:
LATITUDE: 27° 43.2' N ( 27.72000) LONGITUDE: 82° 26.9' W ( -82.44830)
The bench mark is a disk located 37 m (120 ft) NW of the NW corner of the Ruskin
Drive-in Restaurant, 8.08 m (26.5 ft) north of the centerline of Shell Point
Road, 0.49 m (1.6 ft) east of telephone pole #25, and 0.24 m (0.8 ft) south of a
witness post. The bench mark is crimped to the top of a copper-clad steel rod
driven 12.2 m (40 ft) to refusal, 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: 8726467 PUBLICATION DATE: 02/05/2004
Name: MARSH BRANCH, RUSKIN
FL
NOAA Chart: 11412 Latitude: 27° 43.1' N ( 27.71830)
USGS Quad: RUSKIN Longitude: 82° 27.2' W ( -82.45330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: Y 261 1966
DESIGNATION: Y 261
MONUMENTATION: Bench Mark disk VM#: 6511
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: AG6211
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 27° 43.2' N ( 27.72000) LONGITUDE: 82° 26.9' W ( -82.44830)
The bench mark is a disk set in the top of a concrete monument located in front
of Yost Trailer Park, 42.67 m (140.0 ft) SW of the SW corner of the Shop-and-Go
food store, 7.99 m (26.2 ft) north of the centerline of Shell Point Road, 0.37 m
(1.2 ft) west of telephone pole #27, and 0.21 m (0.7 ft) south of a witness
post.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
Station ID: 8726467 PUBLICATION DATE: 02/05/2004
Name: MARSH BRANCH, RUSKIN
FL
NOAA Chart: 11412 Latitude: 27° 43.1' N ( 27.71830)
USGS Quad: RUSKIN Longitude: 82° 27.2' W ( -82.45330)
T I D A L D A T U M S
Tidal datums at MARSH BRANCH, RUSKIN based on:
LENGTH OF SERIES: 2 MONTHS
TIME PERIOD: March 1977 - April 1977
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8726520 ST. PETERSBURG, TAMPA BAY
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 0.658
MEAN HIGH WATER MHW = 0.599
North American Vertical Datum NAVD88 = 0.416
MEAN SEA LEVEL MSL = 0.341
MEAN TIDE LEVEL MTL = 0.335
MEAN LOW WATER MLW = 0.070
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
6467 B 1977 1.084 0.485
6467 C 1977 1.341 0.742
6467 E 1977 1.718 1.119
Y 261 1966 1.654 1.055
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
Station ID: 8726467 PUBLICATION DATE: 02/05/2004
Name: MARSH BRANCH, RUSKIN
FL
NOAA Chart: 11412 Latitude: 27° 43.1' N ( 27.71830)
USGS Quad: RUSKIN Longitude: 82° 27.2' W ( -82.45330)
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.