U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 4
PUBLICATION DATE: 09/29/1989
Station ID: 8447605 SUPERCEDED DATE: 04/21/2003
Name: HYANNIS PORT, HYANNIS HARBOR
MASSACHUSETTS
NOAA Chart: 13237 Latitude: 41° 37.8' N
USGS Quad: HYANNIS Longitude: 70° 18.0' W
To reach the tidal bench marks from Hyannis Port, proceed to the Hyannis Port
Civic Association pier at the intersection of Irving and Iannough Avenues, just
north of the foot of the Hyannis Harbor breakwater. The tidal bench marks are
in the vicinity of the pier base and intersection. The tide gage and staff were
on the SE corner of the pier.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: NO 10 1934
MONUMENTATION: Survey Disk VM#: 2063
AGENCY: PID#: AB7934
SETTING CLASSIFICATION: Curbstone
The bench mark is set in the curbstone on the south side of Irving Avenue, 56
feet (17 m) east of an unnumbered power pole, 23.2 feet (7.1 m) south of the
north curb face of Irving Avenue, and 12.5 feet (3.8 m) west of a fire hydrant.
BENCH MARK STAMPING: NO 9 1934
MONUMENTATION: Survey Disk VM#: 2062
AGENCY: PID:
SETTING CLASSIFICATION: Rock
The bench mark is set in rock, 26.3 feet (8.0 m) ENE of the SE corner of the
Sinclairs residence, 6.0 feet (1.8 m) north of the centerline of the walkway to
the beach, 5.1 feet (1.6 m) east of the face of the retaining wall to the east
of the Sinclairs residence, and 3 feet (1 m) below the top surface of the rock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 4
PUBLICATION DATE: 09/29/1989
Station ID: 8447605 SUPERCEDED DATE: 04/21/2003
Name: HYANNIS PORT, HYANNIS HARBOR
MASSACHUSETTS
NOAA Chart: 13237 Latitude: 41° 37.8' N
USGS Quad: HYANNIS Longitude: 70° 18.0' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: NO 11 1934
MONUMENTATION: Survey Disk VM#: 2064
AGENCY: PID#: AB7935
SETTING CLASSIFICATION: Rock
The bench mark is set in rock along the driveway of the residence on the corner
of Irving and Iannough Avenues, 44.9 feet (13.7 m) north of the north curb face
of Irving Avenue, 36.1 feet (11.0 m) south of the SW corner of the garage, and
2.7 feet (0.8 m) west of the west edge of the driveway.
BENCH MARK STAMPING: NO L8 1954
MONUMENTATION: Survey Disk VM#: 2065
AGENCY: PID:
SETTING CLASSIFICATION: Concrete Base
The bench mark is set in the concrete base of an old telephone booth at the SE
corner of Irving and Iannough Avenues, 13.6 feet (4.1 m) NE of power pole
#BA-444-2MP, 6.6 feet (2.0 m) east of a water valve in the center of a concrete
pad on Irving Avenue, and 3.2 feet (1.0 m) west of the NW corner of the Hyannis
Port Civic Association clubhouse.
BENCH MARK STAMPING: 1000
MONUMENTATION: Brass Plug VM#: 2066
AGENCY: PID:
SETTING CLASSIFICATION: Concrete Pad
The bench mark is set in a concrete pad on Irving Avenue, 10.5 feet (3.2 m) NNE
of power pole #BA-444-2MP, 9.8 feet (3.0 m) west of the NW corner of the Hyannis
Port Civic Association clubhouse, and 0.9 foot (0.3 m) north of a water valve.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 4
PUBLICATION DATE: 09/29/1989
Station ID: 8447605 SUPERCEDED DATE: 04/21/2003
Name: HYANNIS PORT, HYANNIS HARBOR
MASSACHUSETTS
NOAA Chart: 13237 Latitude: 41° 37.8' N
USGS Quad: HYANNIS Longitude: 70° 18.0' W
T I D A L D A T U M S
Tidal datums at HYANNIS PORT, HYANNIS HARBOR based on:
LENGTH OF SERIES: 60 HIGHS, 60 LOWS
TIME PERIOD: SEPT. 17 - OCT. 17, 1983
TIDAL EPOCH: 1960-1978
CONTROL TIDE STATION: 8449130 NANTUCKET
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in FEET:
HIGHEST OBSERVED WATER LEVEL (10/05/1983) = 5.05
MEAN HIGHER HIGH WATER MHHW = 3.80
MEAN HIGH WATER MHW = 3.46
MEAN TIDE LEVEL MTL = 1.85
MEAN LOW WATER MLW = 0.24
MEAN LOWER LOW WATER MLLW = 0.00
LOWEST OBSERVED WATER LEVEL (10/09/1983) = -0.26
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In FEET above:
Stamping or Designation MLLW MHW
NO 10 1934 13.41 9.95
NO 9 1934 5.73 2.27
NO 11 1934 18.09 14.63
NO L8 1954 10.44 6.98
1000 11.05 7.59
Foot Notes:
NOTE: There is no National Geodetic Vertical Datum-1929 (NGVD) connection to
this station. However, there is a Massachusetts Geodetic Survey of 1940 (MGS)
connection that is 1.4 feet above Mean Lower Low Water (MLLW). The MGS values
have never been adjusted or approved by the National Geodetic Survey and no
relationship between NGVD-1929 and MGS datums has been established. Therefore,
these two geodetic datums are not equivalent and cannot be substituted for each
other. The MGS values should be used with appropriate caution.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 4
PUBLICATION DATE: 09/29/1989
Station ID: 8447605 SUPERCEDED DATE: 04/21/2003
Name: HYANNIS PORT, HYANNIS HARBOR
MASSACHUSETTS
NOAA Chart: 13237 Latitude: 41° 37.8' N
USGS Quad: HYANNIS Longitude: 70° 18.0' W
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 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.