U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 4
Station ID: 8630111 PUBLICATION DATE: 07/15/2003
Name: JESTERS ISLAND
VA
NOAA Chart: 12211 Latitude: 37° 58.9' N ( 37.98170)
USGS Quad: CHINCOTEAGUE EAST Longitude: 75° 18.1' W ( -75.30170)
To reach the tidal bench marks from Greenbackville, proceed by boat ESE across
Chincoteague Bay for 6.9 km (3.7 nm) to the north entrance of Assateague Bay,
then ESE for 0.6 km (0.3 nm) to the east side of Assateague Bay to a 1-story
frame building of Jester's Clubhouse. The bench marks are near the clubhouse.
The tide station was on the north end of the wharf.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 0111 A 1985
DESIGNATION: 863 0111 A
MONUMENTATION: Tidal Station disk VM#: 3235
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 37° 58.9' N ( 37.98170) LONGITUDE: 75° 18.1' W ( -75.30170)
The primary bench mark is a disk located on Jester Island, 16 m (53 ft) south of
the north end of the wharf, 4.72 m (15.5 ft) north of the SW corner of Jester's
Clubhouse, and 0.30 m (1.0 ft) west of the NW corner of the clubhouse. The
bench mark is set 0.15 m (0.5 ft) above the ground, crimped to the top of a
stainless steel rod driven 11.0 m (36 ft) to refusal.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 4
Station ID: 8630111 PUBLICATION DATE: 07/15/2003
Name: JESTERS ISLAND
VA
NOAA Chart: 12211 Latitude: 37° 58.9' N ( 37.98170)
USGS Quad: CHINCOTEAGUE EAST Longitude: 75° 18.1' W ( -75.30170)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 0111 B 1985
DESIGNATION: 863 0111 B
MONUMENTATION: Tidal Station disk VM#: 3236
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 37° 58.9' N ( 37.98170) LONGITUDE: 75° 18.1' W ( -75.30170)
The bench mark is a disk located on Jester Island, 15 m (49 ft) SE of the north
end of the wharf, 12.19 m (40.1 ft) NE of the NW corner of Jester's Clubhouse,
and 6.43 m (21.1 ft) NE of the NE corner of the clubhouse. The bench mark is
set 0.15 m (0.5 ft) above the ground, crimped to the top of a stainless steel
rod driven 8.5 m (28 ft) to refusal.
BENCH MARK STAMPING: 0111 C 1985
DESIGNATION: 863 0111 C
MONUMENTATION: Tidal Station disk VM#: 3237
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 37° 58.9' N ( 37.98170) LONGITUDE: 75° 18.1' W ( -75.30170)
The bench mark is a disk located on Jester Island, 60 m (197 ft) west of the
north end of the wharf, 52 m (170 ft) NW of the south end of the wharf, and 0.9
m (3.0 ft) north of a witness post. The bench mark is set 0.15 m (0.5 ft) above
the ground, crimped to the top of a stainless steel rod driven 8.5 m (28 ft) to
refusal.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 4
Station ID: 8630111 PUBLICATION DATE: 07/15/2003
Name: JESTERS ISLAND
VA
NOAA Chart: 12211 Latitude: 37° 58.9' N ( 37.98170)
USGS Quad: CHINCOTEAGUE EAST Longitude: 75° 18.1' W ( -75.30170)
T I D A L D A T U M S
Tidal datums at JESTERS ISLAND based on:
LENGTH OF SERIES: 3 MONTHS
TIME PERIOD: August 1985 - October 1985
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8558690 INDIAN RIVER INLET
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 0.287
MEAN HIGH WATER MHW = 0.261
MEAN TIDE LEVEL MTL = 0.146
MEAN SEA LEVEL MSL = 0.145
MEAN LOW WATER MLW = 0.030
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
0111 A 1985 0.543 0.282
0111 B 1985 0.470 0.209
0111 C 1985 0.504 0.243
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 4
Station ID: 8630111 PUBLICATION DATE: 07/15/2003
Name: JESTERS ISLAND
VA
NOAA Chart: 12211 Latitude: 37° 58.9' N ( 37.98170)
USGS Quad: CHINCOTEAGUE EAST Longitude: 75° 18.1' W ( -75.30170)
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.