U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  5

                                                                                
Station ID: 8448157                         PUBLICATION DATE:  04/06/2012
Name:       VINEYARD HAVEN, VINEYARD HVN HBR                  
            MA
NOAA Chart: 13233                           Latitude:   41° 27.5' N (  41.45830)
USGS Quad:  VINEYARD HAVEN                  Longitude:  70° 36.0' W ( -70.60000)


To reach the tide station at Vineyard Haven from the Vineyard Haven Ferry
Terminal, travel south on Water Street approximately 0.16 km (0.1 mi) to the
intersection known as Five Corners, then turn right on S. Main Street heading
west of the intersection of S. Main Street and Main Street, then turn right onto
Main Street heading north.  Travel on Main Street for 0.32 km (0.2 mi), then
turn right into the William Barry Owen Playground and Recreation Area.  The tide
gauge and staff are located on the end of the Vineyard Haven City Pier in the
William Barry Owent Playground and Recreation Area.


                         T I D A L   B E N C H   M A R K S


                 PRIMARY BENCH MARK STAMPING:  8157 A 1994
                         DESIGNATION:           

MONUMENTATION:           Bench Mark disk                       VM#:        19468
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   41° 27.5' N (  41.45830)          LONGITUDE:  70° 36.0' W ( -70.60000)


The primary bench mark is a disk located in the William Barry Owen Park in
Vineyard Haven, 32.0 m (105.0 ft) SE of the second lightpost from the beach,
22.5 m (73.8 ft) east of the eastern corner of the stone wall along the fence
line, 16.6 m (54.5 ft) west of the west corner of the Harbormaster's shed, and
0.5 m (1.5 ft) NE of the third post from the gate along the fence.  The bench
mark is crimped to a stainless steel rod driven 25.6 m (84.0 ft) to refusal, and
encased in a 5-inch NOS logo cap.



                         BENCH MARK STAMPING:  VH 1 1994
                         DESIGNATION:           

MONUMENTATION:           Bench Mark disk                       VM#:        19469
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete base                         OPUS PID:        
LATITUDE:   41° 27.5' N (  41.45830)          LONGITUDE:  70° 36.0' W ( -70.60000)


The bench mark is a disk set in the southeast corner of the cement base of a
telephone booth at the William Barry Owen Park, located 7.5 m (24.6 ft) NNE of
the NE support foundation of the Vineyard Haven Harbormaster's shed, 12.8 m
(42.0 ft) south of the center of the lower parking area at the park, 64.0 m
(210.0 ft) east of the NE corner of a gazebo, and 126.0 m (413.4 ft) east of the
centerline of Main Street and the intersection of the drive leading to the
parking area of the park.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  5

                                                                                
Station ID: 8448157                         PUBLICATION DATE:  04/06/2012
Name:       VINEYARD HAVEN, VINEYARD HVN HBR                  
            MA
NOAA Chart: 13233                           Latitude:   41° 27.5' N (  41.45830)
USGS Quad:  VINEYARD HAVEN                  Longitude:  70° 36.0' W ( -70.60000)


                         T I D A L   B E N C H   M A R K S


                         BENCH MARK STAMPING:  VH 2 1994

MONUMENTATION:           Bench Mark disk                       VM#:        19470
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Step                                  OPUS PID:        
LATITUDE:   41° 27.5' N (  41.45830)          LONGITUDE:  70° 36.0' W ( -70.60000)


The bench mark is a disk set in the northeast corner of the step to the gazebo
in the William Barry Owen Playground and Recreation Area, located 12.0 m (39.4
ft) SE of the second lightpost counting from Main Street to the gazebo, 32.3 m
(106.0 ft) east of the flagpole in the park, and 52.0 m (170.6 ft) east of the
centerline of Main Street.



                         BENCH MARK STAMPING:  VH 3 1994

MONUMENTATION:           Bench Mark disk                       VM#:        19471
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Flagpole foundation                   OPUS PID#: BBDM85
LATITUDE:   41° 27.5' N (  41.45830)          LONGITUDE:  70° 36.0' W ( -70.60000)


The bench mark is a disk set in the east side of the flagpole foundation in
William Barry Owen Playground and Recreation Area, located 20.3 m (66.6 ft) east
of the centerline of the drive leading to the park, 16.0 m (52.5 ft) south of
the first power pole in the park counting from Main Street to the gazebo marked
NET&T Co, 109, 1, C&VECO, and 17.7 m (58.1 ft) southeast of the first lightpost
counting from Main Street to the gazebo.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  5

                                                                                
Station ID: 8448157                         PUBLICATION DATE:  04/06/2012
Name:       VINEYARD HAVEN, VINEYARD HVN HBR                  
            MA
NOAA Chart: 13233                           Latitude:   41° 27.5' N (  41.45830)
USGS Quad:  VINEYARD HAVEN                  Longitude:  70° 36.0' W ( -70.60000)


                         T I D A L   B E N C H   M A R K S


                         BENCH MARK STAMPING:  8157 B 1994

MONUMENTATION:           Bench Mark disk                       VM#:        19472
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   41° 27.5' N (  41.45830)          LONGITUDE:  70° 36.0' W ( -70.60000)


The bench mark is a disk located in the William Barry Owen Park in Vineyard
Haven, 30.3 m (99.4 ft) north of the second lightpost from the beach, 24.1 m
(79.1 ft) east of telephone pole #2, 11.3 m (37.1 ft) NE of the north side of
the drive leaing to the park area, and 3.4 m (11.2 ft) SW of a power pole.  The
bench mark is crimped to a stainless steel rod driven 18.3 m (60.0 ft) to
refusal, and encased in a 5-inch NOS logo cap.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  5

                                                                                
Station ID: 8448157                         PUBLICATION DATE:  04/06/2012
Name:       VINEYARD HAVEN, VINEYARD HVN HBR                  
            MA
NOAA Chart: 13233                           Latitude:   41° 27.5' N (  41.45830)
USGS Quad:  VINEYARD HAVEN                  Longitude:  70° 36.0' W ( -70.60000)


                            T I D A L   D A T U M S 


Tidal datums at VINEYARD HAVEN, VINEYARD HVN HBR based on:

     LENGTH OF SERIES:      2 MONTHS
     TIME PERIOD:           July 1994 - August 1994
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8447930 WOODS HOLE, BUZZARDS BAY


Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:

     MEAN HIGHER HIGH WATER                     MHHW   =  0.648
     MEAN HIGH WATER                            MHW    =  0.534
     MEAN SEA LEVEL                             MSL    =  0.323
     MEAN TIDE LEVEL                            MTL    =  0.291
     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

     8157 A 1994                                 1.905    1.371
     VH 1 1994                                   2.221    1.687
     VH 2 1994                                   8.461    7.927
     VH 3 1994                                  11.797   11.263
     8157 B 1994                                 7.803    7.269


                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  5

                                                                                
Station ID: 8448157                         PUBLICATION DATE:  04/06/2012
Name:       VINEYARD HAVEN, VINEYARD HVN HBR                  
            MA
NOAA Chart: 13233                           Latitude:   41° 27.5' N (  41.45830)
USGS Quad:  VINEYARD HAVEN                  Longitude:  70° 36.0' W ( -70.60000)


                             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.