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

                                                                                
Station ID: 8447495                         PUBLICATION DATE:  04/21/2003
Name:       SAQUATUCKET HARBOR                                
            MA
NOAA Chart: 13246                           Latitude:   41° 40.1' N (  41.66830)
USGS Quad:  HARWICH                         Longitude:  70°  3.4' W ( -70.05670)


To reach the tidal bench marks from the intersection of Route 6 and 134 in South
Dennis, proceed south on Route 134 for 3.7 km (2.3 mi) to Route 28, then east on
Route 28 for 8.0 km (5.0 mi) to Saquatucket Harbor.  The bench marks are in the
vicinity of the harbor parking lot, and the tide gauge and staff were attached
to floating dock pilings south of the Harbormaster's office.


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


                 PRIMARY BENCH MARK STAMPING:  7495 A 1993
                         DESIGNATION:          844 7495 A

MONUMENTATION:           Tidal Station disk                    VM#:        12472
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete sea wall                     OPUS PID:        
LATITUDE:   41° 40.1' N (  41.66830)          LONGITUDE:  70°  3.4' W ( -70.05670)


The primary bench mark is a disk set in the concrete seawall cap of Saquatucket
Harbor, 20.70 m (67.9 ft) east of the western corner of the sea wall, 7.92 m
(26.0 ft) SW of the NW corner of a small utility building, and 5.49 m (18.0 ft)
SW of the centerline of the small road fronting the harbor.

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

                                                                                
Station ID: 8447495                         PUBLICATION DATE:  04/21/2003
Name:       SAQUATUCKET HARBOR                                
            MA
NOAA Chart: 13246                           Latitude:   41° 40.1' N (  41.66830)
USGS Quad:  HARWICH                         Longitude:  70°  3.4' W ( -70.05670)


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


                         BENCH MARK STAMPING:  7495 B 1993
                         DESIGNATION:          844 7495 B

MONUMENTATION:           Tidal Station disk                    VM#:        12473
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete wing wall                    OPUS PID:        
LATITUDE:   41° 40.1' N (  41.66830)          LONGITUDE:  70°  3.4' W ( -70.05670)


The bench mark is a disk set in the dogleg corner of the concrete wingwall on
the east side of Brax Landing Restaurant, 29.41 m (96.5 ft) north of the
westernmost group of piles at the entrance to the road fronting Saquatucket
Harbor, 13.87 m (45.5 ft) WSW of the edge of the Saquatucket Harbor parking lot,
10.21 m (33.5 ft) SE of the NE corner of Brax Landing, and 1.37 m (4.5 ft) above
grade.



                         BENCH MARK STAMPING:  7495 C 1993
                         DESIGNATION:          844 7495 C

MONUMENTATION:           Tidal Station disk                    VM#:        12474
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete foundation                   OPUS PID:        
LATITUDE:   41° 40.1' N (  41.66830)          LONGITUDE:  70°  3.4' W ( -70.05670)


The bench mark is a disk set in the southern edge of the 1 m (2 ft) diameter
concrete flagpole base at Thompsons Farm Market (710 Route 28), 24.38 m (80.0
ft) NE of telephone pole No. 81, 22.40 m (73.5 ft) SW of the SW corner of the
market, and 9.94 m (32.6 ft) NNW of the centerline of Route 28.

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

                                                                                
Station ID: 8447495                         PUBLICATION DATE:  04/21/2003
Name:       SAQUATUCKET HARBOR                                
            MA
NOAA Chart: 13246                           Latitude:   41° 40.1' N (  41.66830)
USGS Quad:  HARWICH                         Longitude:  70°  3.4' W ( -70.05670)


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


                         BENCH MARK STAMPING:  7495 D 1993
                         DESIGNATION:          844 7495 D

MONUMENTATION:           Tidal Station disk                    VM#:        12475
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete head wall                    OPUS PID:        
LATITUDE:   41° 40.1' N (  41.66830)          LONGITUDE:  70°  3.4' W ( -70.05670)


The bench mark is a disk set in the western end of the lower tier of a concrete
headwall over the small stream just west of Saquatucket Harbor and on the south
side of Route 28, 11.37 m (37.3 ft) SSW of telephone pole  No. 79, 8.99 m (29.5
ft) SSE of the centerline of Route 28, 0.46 m (1.5 ft) ENE of the western end of
the lower end of the headwall, and 2 m (6 ft) below the surface of the road.



                         BENCH MARK STAMPING:  TBM SLAB 1993
                         DESIGNATION:          844 7495 TBM SLAB

MONUMENTATION:           Survey disk                           VM#:        12476
AGENCY:                  US Army Corps of Engineers (USE)      IDB PID#:        
SETTING CLASSIFICATION:  Concrete foundation                   OPUS PID:        
LATITUDE:   41° 40.1' N (  41.66830)          LONGITUDE:  70°  3.4' W ( -70.05670)


The bench mark is a disk set in the SW corner of a concrete pad supporting a
large green utility box adjacent to the harbormasters building, 15.24 m (50.0
ft) ENE of a large flagpole, 15.24 m (50.0 ft) NE of the seawall, and 5.88 m
(19.3 ft) SSE of the SE corner of the harbormaster building.

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

                                                                                
Station ID: 8447495                         PUBLICATION DATE:  04/21/2003
Name:       SAQUATUCKET HARBOR                                
            MA
NOAA Chart: 13246                           Latitude:   41° 40.1' N (  41.66830)
USGS Quad:  HARWICH                         Longitude:  70°  3.4' W ( -70.05670)


                            T I D A L   D A T U M S 


Tidal datums at SAQUATUCKET HARBOR based on:

     LENGTH OF SERIES:      5 Months
     TIME PERIOD:           May 1993 - September 1993
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8449130 NANTUCKET ISLAND, NANTUCKET SOUND


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

     MEAN HIGHER HIGH WATER                     MHHW   =  1.325
     MEAN HIGH WATER                            MHW    =  1.220
     North American Vertical Datum              NAVD88 =  0.788
     MEAN SEA LEVEL                             MSL    =  0.682
     MEAN TIDE LEVEL                            MTL    =  0.652
     MEAN LOW WATER                             MLW    =  0.085
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     7495 A 1993                                 2.334    1.114
     7495 B 1993                                 4.502    3.282
     7495 C 1993                                 3.780    2.560
     7495 D 1993                                 2.186    0.966
     TBM SLAB 1993                               3.330    2.110


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

                                                                                
Station ID: 8447495                         PUBLICATION DATE:  04/21/2003
Name:       SAQUATUCKET HARBOR                                
            MA
NOAA Chart: 13246                           Latitude:   41° 40.1' N (  41.66830)
USGS Quad:  HARWICH                         Longitude:  70°  3.4' W ( -70.05670)


                             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.