U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 6
Station ID: 8512735 PUBLICATION DATE: 10/06/2011
Name: SOUTH JAMESPORT, GREAT PECONIC BAY
NY
NOAA Chart: 12358 Latitude: 40° 56.1' N ( 40.93500)
USGS Quad: MATTITUCK Longitude: 72° 34.9' W ( -72.58170)
To reach the tidal bench marks from the intersection of State Highway 25 and
County Road 105 in Riverhead, proceed east on State Highway 25 for 4.8 km (3.0
mi) to the village of Jamesport, then south on Washington Avenue for 1.3 km (0.8
mi) to Great Peconic Bay Marina on the right. The bench marks are near the
marina and nearby streets. The tide gage and staff were located on the east
bulkhead of the marina entrance channel.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 2735 A 1988
DESIGNATION: 851 2735 A TIDAL
MONUMENTATION: Tidal Station disk VM#: 2296
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 40° 56.1' N ( 40.93500) LONGITUDE: 72° 34.9' W ( -72.58170)
The primary bench mark is a disk located near the NE corner of the entrance
channel to Great Peconic Bay Marina located at the west end of the Very
Important Boat (V.I.B.) area of the marina, 2.74 m (9.0 ft) south of a light
pole at the SW corner of the V.I.B. area, 1.77 m (5.8 ft) east of the inside
face of the east channel bulkhead, and 1.28 m (4.2 ft) WNW of the NW corner of
the parking lot. The bench mark is crimped to the top of a stainless steel rod
driven to an unspecified depth, and encased in a PVC pipe with a NOAA access
cover and concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 6
Station ID: 8512735 PUBLICATION DATE: 10/06/2011
Name: SOUTH JAMESPORT, GREAT PECONIC BAY
NY
NOAA Chart: 12358 Latitude: 40° 56.1' N ( 40.93500)
USGS Quad: MATTITUCK Longitude: 72° 34.9' W ( -72.58170)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: NO 1 1917
DESIGNATION: TIDAL 1 STA II 35
MONUMENTATION: Tidal Station disk VM#: 2295
AGENCY: US Coast & Geodetic Survey
(USC&GS) IDB PID#: KU0373
SETTING CLASSIFICATION: Granite wall OPUS PID:
LATITUDE: 40° 56.0' N ( 40.93330) LONGITUDE: 72° 34.6' W ( -72.57670)
The bench mark is a disk set in the top of a low granite wall located near the
Great Peconic Bay end of South Jamesport Avenue, 119 m (390 ft) south of the
centerline of Front Street, 8.66 m (28.4 ft) north of LIL power pole #53, and
6.46 m (21.2 ft) west of the centerline of South Jamesport Avenue. NOTE: The
edge of the disk away from the street is the high point used for leveling.
BENCH MARK STAMPING: 2735 B 1988
DESIGNATION: 851 2735 B TIDAL
MONUMENTATION: Tidal Station disk VM#: 2297
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 40° 56.1' N ( 40.93500) LONGITUDE: 72° 34.9' W ( -72.58170)
The bench mark is a disk located at the east end of Very Important Boat (V.I.B.)
area of the marina, 141 m (462 ft) east of bench mark 2735 A 1988, 21 m (69 ft)
west of the south gate post at the east end of the V.I.B. area, 11.92 m (39.1
ft) south of the SE corner pile of the marina, 1.46 m (4.8 ft) NE of the lowest
crotch of a wild cherry tree, and 0.76 m (2.5 ft) south of the center of a
square wooden post. The bench mark is crimped to the top of a stainless steel
rod driven to an unspecified depth, and encased in a PVC pipe and concrete
kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 6
Station ID: 8512735 PUBLICATION DATE: 10/06/2011
Name: SOUTH JAMESPORT, GREAT PECONIC BAY
NY
NOAA Chart: 12358 Latitude: 40° 56.1' N ( 40.93500)
USGS Quad: MATTITUCK Longitude: 72° 34.9' W ( -72.58170)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 2735 C 1988
DESIGNATION: 851 2735 C TIDAL
MONUMENTATION: Tidal Station disk VM#: 2298
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 40° 56.1' N ( 40.93500) LONGITUDE: 72° 34.9' W ( -72.58170)
The bench mark is a disk located near the first house along the beach east of
the marina entrance channel, 75.62 m (248.1 ft) ENE of the three pile cluster at
the south end of the east channel bulkhead, 12.98 m (42.6 ft) south of the SW
corner of a garage, 10.24 m (33.6 ft) NNW of the SW corner of the house, and
0.58 m (1.9 ft) east of a chainlink fence. The bench mark is crimped to the top
of a stainless steel rod driven to an unspecified depth, and encased in a PVC
pipe and concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 6
Station ID: 8512735 PUBLICATION DATE: 10/06/2011
Name: SOUTH JAMESPORT, GREAT PECONIC BAY
NY
NOAA Chart: 12358 Latitude: 40° 56.1' N ( 40.93500)
USGS Quad: MATTITUCK Longitude: 72° 34.9' W ( -72.58170)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: W 326 1943
DESIGNATION: W 326
MONUMENTATION: Bench Mark disk VM#: 17656
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: KU0371
SETTING CLASSIFICATION: Railroad bridge abutment OPUS PID:
LATITUDE: 40° 56.6' N ( 40.94330) LONGITUDE: 72° 34.8' W ( -72.58000)
The bench mark is a disk set vertically in the face of the east abutment loacted
at a Long Island railroad overpass, 6.49 m (21.3 ft) south of the north corner
of the abutment, 3 m (10 ft) east of the centerline of the road, and 1.58 m (5.2
ft) above the road.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 6
Station ID: 8512735 PUBLICATION DATE: 10/06/2011
Name: SOUTH JAMESPORT, GREAT PECONIC BAY
NY
NOAA Chart: 12358 Latitude: 40° 56.1' N ( 40.93500)
USGS Quad: MATTITUCK Longitude: 72° 34.9' W ( -72.58170)
T I D A L D A T U M S
Tidal datums at SOUTH JAMESPORT, GREAT PECONIC BAY based on:
LENGTH OF SERIES: 2 YEARS
TIME PERIOD: May 2005 - April 2007
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8461490 NEW LONDON, THAMES RIVER
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
HIGHEST OBSERVED WATER LEVEL (02/12/2006) = 1.954
MEAN HIGHER HIGH WATER MHHW = 1.007
MEAN HIGH WATER MHW = 0.917
MEAN SEA LEVEL MSL = 0.497
MEAN TIDE LEVEL MTL = 0.485
MEAN LOW WATER MLW = 0.053
MEAN LOWER LOW WATER MLLW = 0.000
LOWEST OBSERVED WATER LEVEL (03/09/2005) = -0.668
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
2735 A 1988 2.090 1.173
NO 1 1917 1.848 0.931
2735 B 1988 2.254 1.337
2735 C 1988 2.286 1.369
W 326 1943 4.071 3.154
Foot Notes:
Bench marks NO 1 1917 and W 326 1943 are based on one differential leveling
connection and do not meet the quality control standards of the NOS. Therefore,
caution should be used when deriving elevations for these marks.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 6
Station ID: 8512735 PUBLICATION DATE: 10/06/2011
Name: SOUTH JAMESPORT, GREAT PECONIC BAY
NY
NOAA Chart: 12358 Latitude: 40° 56.1' N ( 40.93500)
USGS Quad: MATTITUCK Longitude: 72° 34.9' W ( -72.58170)
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.