U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 6
Station ID: 8658741 PUBLICATION DATE: 06/16/2004
Name: ZEKES ISLAND, CAPE FEAR RIVER
NC
NOAA Chart: 11537 Latitude: 33° 57.0' N ( 33.95000)
USGS Quad: KURE BEACH Longitude: 77° 57.1' W ( -77.95170)
To reach the tidal bench marks from Federal Point ferry landing, proceed by boat
east for 1.0 km (0.6 mi) and then SSE for 1.4 km (0.9 mi) to the break water,
known as The Rocks, at the NW end of Zekes Island. The bench marks are located
along and on the east side of the breakwater. The tide gage and staff were
located on a range marker about 213 m (700 ft) west of the breakwater. To reach
the tidal bench marks by foot, proceed from the end of U.S. Highway 421 at
Federal Point and walk along The Rocks (breakwater) for about 1.53 km (0.95 mi)
to the NW end of Zekes Island.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 8741 A 1976
DESIGNATION: 865 8741 A TIDAL
MONUMENTATION: Tidal Station disk VM#: 3619
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Unspecified steel rod OPUS PID:
LATITUDE: 33° 57.0' N ( 33.95000) LONGITUDE: 77° 57.1' W ( -77.95170)
The primary bench mark is a disk located along the breakwater known as The Rocks
about 1.53 km (0.95 mi) SW of Federal Point, 68 m (223 ft) south of bench mark
THE ROCKS 1976, and 2.29 m (7.5 ft) east of the eastern edge of the breakwater.
The bench mark is crimped to the top of an unspecified steel rod driven to a
depth of 7.3 m (24 ft).
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 6
Station ID: 8658741 PUBLICATION DATE: 06/16/2004
Name: ZEKES ISLAND, CAPE FEAR RIVER
NC
NOAA Chart: 11537 Latitude: 33° 57.0' N ( 33.95000)
USGS Quad: KURE BEACH Longitude: 77° 57.1' W ( -77.95170)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: ZEKE 1932
DESIGNATION: ZEKE
MONUMENTATION: Triangulation Station disk VM#: 3617
AGENCY: US Coast & Geodetic Survey
(USC&GS) IDB PID#: DD0007
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 33° 56.9' N ( 33.94830) LONGITUDE: 77° 56.9' W ( -77.94830)
The bench mark is a disk set in the top of a concrete monument along the break
water known as The Rocks, about 1.54 km (0.96 mi) SW of Federal Point, 4 m (12
ft) east of the eastern edge of the break water, and 0.3 m (1 ft) above the
ground.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 6
Station ID: 8658741 PUBLICATION DATE: 06/16/2004
Name: ZEKES ISLAND, CAPE FEAR RIVER
NC
NOAA Chart: 11537 Latitude: 33° 57.0' N ( 33.95000)
USGS Quad: KURE BEACH Longitude: 77° 57.1' W ( -77.95170)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: THE ROCKS 1976
DESIGNATION: THE ROCKS
MONUMENTATION: Survey disk VM#: 3618
AGENCY: North Carolina Geodetic Survey (NCGS) IDB PID#: DD1012
SETTING CLASSIFICATION: Sidewalk OPUS PID:
LATITUDE: 33° 57.0' N ( 33.95000) LONGITUDE: 77° 57.0' W ( -77.95000)
The bench mark is a disk set in the concrete sidewalk along the breakwater known
as The Rocks, about 1.53 km (0.95 mi) SW of Federal Point, at the NW point of
Zekes Island.
BENCH MARK STAMPING: 8741 B 1976
DESIGNATION: 865 8741 B TIDAL
MONUMENTATION: Tidal Station disk VM#: 3620
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Unspecified steel rod OPUS PID:
LATITUDE: 33° 57.0' N ( 33.95000) LONGITUDE: 77° 57.1' W ( -77.95170)
The bench mark is a disk located along the breakwater known as The Rocks about
1.57 km (0.97 mi) SW of Federal Point, 87 m (286 ft) south of bench mark ZEKE
1932, and approximately 8.38 m (27.5 ft) east of the breakwater. The bench mark
is crimped to the top of an unspecified steel rod driven to an depth of 7.0 m
(23 ft).
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 6
Station ID: 8658741 PUBLICATION DATE: 06/16/2004
Name: ZEKES ISLAND, CAPE FEAR RIVER
NC
NOAA Chart: 11537 Latitude: 33° 57.0' N ( 33.95000)
USGS Quad: KURE BEACH Longitude: 77° 57.1' W ( -77.95170)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 8741 C 1976
DESIGNATION: 865 8741 C TIDAL
MONUMENTATION: Tidal Station disk VM#: 3621
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Unspecified steel rod OPUS PID:
LATITUDE: 33° 57.0' N ( 33.95000) LONGITUDE: 77° 57.1' W ( -77.95170)
The bench mark is a disk located along the breakwater known as The Rocks about
1.58 km (0.98 mi) SW of Federal Point, 63 m (207 ft) south of bench mark 8741 B
1976, and 6 m (20 ft) east of the eastern edge of the breakwater. The bench
mark is crimped to the top of an unspecified steel rod driven to a depth of 12.2
m (40 ft).
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 6
Station ID: 8658741 PUBLICATION DATE: 06/16/2004
Name: ZEKES ISLAND, CAPE FEAR RIVER
NC
NOAA Chart: 11537 Latitude: 33° 57.0' N ( 33.95000)
USGS Quad: KURE BEACH Longitude: 77° 57.1' W ( -77.95170)
T I D A L D A T U M S
Tidal datums at ZEKES ISLAND, CAPE FEAR RIVER based on:
LENGTH OF SERIES: 3 MONTHS
TIME PERIOD: April 1976 - June 1976
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8658120 WILMINGTON, CAPE FEAR RIVER
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 1.392
MEAN HIGH WATER MHW = 1.294
North American Vertical Datum NAVD88 = 0.820
MEAN SEA LEVEL MSL = 0.678
MEAN TIDE LEVEL MTL = 0.671
MEAN LOW WATER MLW = 0.048
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
8741 A 1976 1.854 0.560
ZEKE 1932 1.918 0.624
THE ROCKS 1976 1.713 0.419
8741 B 1976 1.973 0.679
8741 C 1976 1.781 0.487
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 6
Station ID: 8658741 PUBLICATION DATE: 06/16/2004
Name: ZEKES ISLAND, CAPE FEAR RIVER
NC
NOAA Chart: 11537 Latitude: 33° 57.0' N ( 33.95000)
USGS Quad: KURE BEACH Longitude: 77° 57.1' W ( -77.95170)
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.