U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
Station ID: 8724991 PUBLICATION DATE: 05/19/2003
Name: MARCO, BIG MARCO RIVER
FL
NOAA Chart: 11429 Latitude: 25° 58.3' N ( 25.97170)
USGS Quad: CUSTARD APPLE HAMOCK Longitude: 81° 44.0' W ( -81.73330)
To reach the tidal bench marks from the junction of State Roads 92 and 951 on
Marco Island, proceed north and NE on State Road 951 for 2.4 km (1.5 mi) to Bald
Eagle Drive, then north on Bald Eagle Drive for 2.17 km (1.35 mi) to Snook Inn
Restaurant and Motel. The bench marks are at Snook Inn Restaurant and along
Bald Eagle Drive. The tide gage and staff were at the boat docks behind Snook
Inn Restaurant.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 4991 A 1989
DESIGNATION: 872 4991 A TIDAL
MONUMENTATION: Tidal Station disk VM#: 9758
AGENCY: National Ocean Service (NOS) IDB PID#: AA7622
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 25° 58.4' N ( 25.97330) LONGITUDE: 81° 43.7' W ( -81.72830)
The primary bench mark is a disk, 42.67 m NE of the centerline of Bald Eagle
Drive, 19.51 m (64.0 ft) NW of the extended centerline of Palm Street, 17.37 m
(57.0 ft) SE of the driveway leading into the Snook Inn Restuarant and Bar, 2.99
m (9.8 ft) NW of a three trunked tree, and .67 m (2.2 ft) NE of the NE corner of
a private asphalt parking area. The bench mark is crimped to a stainless steel
rod driven an unspecified depth 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: 8724991 PUBLICATION DATE: 05/19/2003
Name: MARCO, BIG MARCO RIVER
FL
NOAA Chart: 11429 Latitude: 25° 58.3' N ( 25.97170)
USGS Quad: CUSTARD APPLE HAMOCK Longitude: 81° 44.0' W ( -81.73330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 4991 B 1989
DESIGNATION: 872 4991 B TIDAL
MONUMENTATION: Tidal Station disk VM#: 9759
AGENCY: National Ocean Service (NOS) IDB PID#: AA7623
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 25° 58.3' N ( 25.97170) LONGITUDE: 81° 43.7' W ( -81.72830)
The bench mark is a disk, 49.23 m (161.5 ft) SE of the extended centerline of
Tampa Place (an asphalt driveway on the easterly side of Bald Eagle Drive),
34.90 m (114.5 ft) north of the center of the driveway to Marco Vista
Apartments, 8.99 m (29.5 ft) SW of the centerline of Bald Eagle Drive, and 3.17
m (10.4 ft) NW of an historic rock monument for Captain William D. Collier. The
bench mark is crimped to a stainless steel rod driven an unspecified depth to
refusal, and encased in a PVC pipe and concrete kickblock.
BENCH MARK STAMPING: 4991 C 1989
DESIGNATION: 872 4991 C TIDAL
MONUMENTATION: Tidal Station disk VM#: 9760
AGENCY: National Ocean Service (NOS) IDB PID#: AA7624
SETTING CLASSIFICATION: Sign foundation OPUS PID:
LATITUDE: 25° 57.6' N ( 25.96000) LONGITUDE: 81° 43.7' W ( -81.72830)
The bench mark is a disk set flush in the top of an old concrete sign foundation
located near Marco River Marina, 50.29 m (165.0 ft) SE of the center of the
asphalt entrance driveway on the northernly side of the marina, 37.37 m (122.6
ft) NW of the center of the asphalt exit driveway, 18.20 m (59.7 ft) NE of the
centerline of Bald Eagle Drive, 4.51 m (14.8 ft) east of the easterly edge of a
2 m (5 ft) wide asphalt walk, 4.15 m (13.6 ft) SW of the SW corner of the new
concrete foundation supporting the Marco River Marina sign, 2.50 m (8.2 ft) east
of a three rail white vinyl plank, and 0.30 m (1.0 ft) above the ground.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
Station ID: 8724991 PUBLICATION DATE: 05/19/2003
Name: MARCO, BIG MARCO RIVER
FL
NOAA Chart: 11429 Latitude: 25° 58.3' N ( 25.97170)
USGS Quad: CUSTARD APPLE HAMOCK Longitude: 81° 44.0' W ( -81.73330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 4991 D 1989
DESIGNATION: 872 4991 D TIDAL
MONUMENTATION: Tidal Station disk VM#: 9761
AGENCY: National Ocean Service (NOS) IDB PID#: AA7625
SETTING CLASSIFICATION: Concrete box drain OPUS PID#: AA7625
LATITUDE: 25° 57.6' N ( 25.96000) LONGITUDE: 81° 43.6' W ( -81.72670)
The bench mark is a disk set flush on top of the NE corner of a concrete box
drain, 44.71 m (146.7 ft) east of the southern asphalt driveway exiting Anglers
Plaza, 37.55 m (123.2 ft) NW of the center of the northern asphalt driveway
entrance into Lanai Plaza, 12.92 m (42.4 ft) SW of the centerline of Bald Eagle
Drive, 7.80 m (25.6 ft) SE of an extended centerline of the North Barfield
Drive, 0.70 m (2.3 ft) SW of the westerly side of a 1m (4 ft) wide concrete
sidewalk, and 0.30 m (1.0 ft) below the Bald Eagle Drive.
BENCH MARK STAMPING: 4991 E 1989
DESIGNATION: 872 4991 E TIDAL
MONUMENTATION: Tidal Station disk VM#: 9762
AGENCY: National Ocean Service (NOS) IDB PID#: AA7621
SETTING CLASSIFICATION: Patio slab OPUS PID:
LATITUDE: 25° 58.4' N ( 25.97330) LONGITUDE: 81° 43.7' W ( -81.72830)
The bench mark is a disk set flush on the concrete patio slab, 4.30 m (14.1 ft)
SE of the southerly storefront side of the dining room of the Snook Inn
Restuarant, 1.25 m (4.1 ft) NE of the waterside face (easterly face) of the
Stucco Finish Building, and 0.18 m (0.6 ft) NE of the easterly edge of a wod
stairway leading up to the second floor of the building.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
Station ID: 8724991 PUBLICATION DATE: 05/19/2003
Name: MARCO, BIG MARCO RIVER
FL
NOAA Chart: 11429 Latitude: 25° 58.3' N ( 25.97170)
USGS Quad: CUSTARD APPLE HAMOCK Longitude: 81° 44.0' W ( -81.73330)
T I D A L D A T U M S
Tidal datums at MARCO, BIG MARCO RIVER based on:
LENGTH OF SERIES: 1 MONTH
TIME PERIOD: July 1989 - July 1989
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8725110 NAPLES, GULF OF MEXICO
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 0.846
MEAN HIGH WATER MHW = 0.779
North American Vertical Datum NAVD88 = 0.649
MEAN TIDE LEVEL MTL = 0.467
MEAN SEA LEVEL MSL = 0.457
MEAN LOW WATER MLW = 0.155
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
4991 A 1989 2.759 1.980
4991 B 1989 2.358 1.579
4991 C 1989 2.032 1.253
4991 D 1989 1.320 0.541
4991 E 1989 1.275 0.496
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
Station ID: 8724991 PUBLICATION DATE: 05/19/2003
Name: MARCO, BIG MARCO RIVER
FL
NOAA Chart: 11429 Latitude: 25° 58.3' N ( 25.97170)
USGS Quad: CUSTARD APPLE HAMOCK Longitude: 81° 44.0' W ( -81.73330)
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.