U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  7

                                                                                
Station ID: 8447241                         PUBLICATION DATE:  04/21/2003
Name:       SESUIT HARBOR, EAST DENNIS                        
            MA
NOAA Chart: 13246                           Latitude:   41° 45.1' N (  41.75170)
USGS Quad:  DENNIS                          Longitude:  70°  9.3' W ( -70.15500)


To reach the bench marks from the intersection of Bridge Street (Route 134) and
Route 6, proceed north on Bridge Street for 5.3 km (3.3 mi) to the intersection
of Route 6A and Bridge Street, then continue north on Bridge Street for 0.6 km
(0.4 mi) to Sesuit Neck Road, proceed NW on Sesuit Neck Road for 1.0 km (0.6 mi)
to the Town of Dennis Municipal Dock.  The bench marks are in the vicinity of
the town dock and the adjacent Northside Marina, and the tide gauge and staff
were on the east end of the town dock.


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


                 PRIMARY BENCH MARK STAMPING:  7241 A 1993
                         DESIGNATION:          844 7241 A

MONUMENTATION:           Tidal Station disk                    VM#:        12466
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete footing                      OPUS PID:        
LATITUDE:   41° 45.1' N (  41.75170)          LONGITUDE:  70°  9.3' W ( -70.15500)


The primary bench mark is a disk set in the concrete footing of the SW corner of
the southermost building at the Northside Marina, 37 m (121 ft) west of the SE
corner of the building, 23 m (75 ft) north of the center of the boat ramp, 0.43
m (1.4 ft) ESE of the SW corner of the building, and 0.18 m (0.6 ft) above
ground.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  7

                                                                                
Station ID: 8447241                         PUBLICATION DATE:  04/21/2003
Name:       SESUIT HARBOR, EAST DENNIS                        
            MA
NOAA Chart: 13246                           Latitude:   41° 45.1' N (  41.75170)
USGS Quad:  DENNIS                          Longitude:  70°  9.3' W ( -70.15500)


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


                         BENCH MARK STAMPING:  7241 B 1993
                         DESIGNATION:          844 7241 B

MONUMENTATION:           Tidal Station disk                    VM#:        12467
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete sea wall                     OPUS PID#: BBBJ59
LATITUDE:   41° 45.1' N (  41.75170)          LONGITUDE:  70°  9.3' W ( -70.15500)


The bench mark is a disk set in the concrete sea wall at the NE end of Northside
Marina, 39.78 m (130.5 ft) north of the north edge of the boat deployment dock,
27.58 m (90.5 ft) ENE of the NE corner of the northernmost building of the
marina, 0.09 m (0.3 ft) ESE of the north edge of the seawall, and 0.06 m (0.2
ft) above ground.



                         BENCH MARK STAMPING:  7241 C 1993
                         DESIGNATION:          844 7241 C

MONUMENTATION:           Tidal Station disk                    VM#:        12468
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete wall                         OPUS PID:        
LATITUDE:   41° 45.1' N (  41.75170)          LONGITUDE:  70°  9.3' W ( -70.15500)


The bench mark is a disk set in the top of the south wall of the Dennis Yacht
Club tennis courts, 28.56 m (93.7 ft) east of the west corner of the south wall,
2.68 m (8.8 ft) west of the east corner of the south wall, 0.06 m (0.2 ft) NW of
the south edge of the wall, and 1 m (3 ft) above the tennis court.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  7

                                                                                
Station ID: 8447241                         PUBLICATION DATE:  04/21/2003
Name:       SESUIT HARBOR, EAST DENNIS                        
            MA
NOAA Chart: 13246                           Latitude:   41° 45.1' N (  41.75170)
USGS Quad:  DENNIS                          Longitude:  70°  9.3' W ( -70.15500)


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


                         BENCH MARK STAMPING:  7241 D 1993
                         DESIGNATION:          844 7241 D

MONUMENTATION:           Tidal Station disk                    VM#:        12469
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Bedrock outcrop                       OPUS PID:        
LATITUDE:   41° 45.1' N (  41.75170)          LONGITUDE:  70°  9.3' W ( -70.15500)


The bench mark is a disk set in the top of a bedrock outcrop on the west side of
Sesuit Neck Road, 17 m (56 ft) WSW of utility pole #24, 9 m (29 ft) west of the
road centerline, 0.85 m (2.8 ft) east of the west point of the outcrop, and 2 m
(6 ft) above ground.



                         BENCH MARK STAMPING:  D 1974
                         DESIGNATION:          844 7241 USE D

MONUMENTATION:           Survey disk                           VM#:        12470
AGENCY:                  US Army Corps of Engineers (USE)      IDB PID#:        
SETTING CLASSIFICATION:  Concrete fence post                   OPUS PID:        
LATITUDE:   41° 45.1' N (  41.75170)          LONGITUDE:  70°  9.3' W ( -70.15500)


The bench mark is a disk set in top of a fence post located on the SE side of
Sesuit Neck Road, 16.89 m (55.4 ft) WSW of utility pole 72/20A along the NW edge
of the Municipal Pier parking lot, 11.28 m (37.0 ft) SE of the road centerline,
3.51 m (11.5 ft) ESE of the SE corner of the Shiverick Shipyard monument, and
0.88 m (2.9 ft) above ground.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  7

                                                                                
Station ID: 8447241                         PUBLICATION DATE:  04/21/2003
Name:       SESUIT HARBOR, EAST DENNIS                        
            MA
NOAA Chart: 13246                           Latitude:   41° 45.1' N (  41.75170)
USGS Quad:  DENNIS                          Longitude:  70°  9.3' W ( -70.15500)


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


                         BENCH MARK STAMPING:  139G
                         DESIGNATION:          844 7241 139G

MONUMENTATION:           Traverse Station disk                 VM#:        12471
AGENCY:                  Massachusetts Department of Public Works
                         (MDPW)                                IDB PID#:        
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   41° 44.5' N (  41.74170)          LONGITUDE:  70°  9.7' W ( -70.16170)


The bench mark is a disk set in a 0.27 m (0.9 ft) diameter concrete monument
located on the west side of State Route 134 south of the intersection of Route
134 and State Route 6A in the town of East Dennis, 19.32 m (63.4 ft) SW of a
nail in power pole No. 36/449, 11.73 m (38.5 ft) north of a nail in light pole
No. 37C/234, 11 m (36 ft) south of Route 6A, 9.08 m (29.8 ft) NE of the corner
of Clear View Cottage, 6 m (20 ft) west of Route 134, and 0.03 m (0.1 ft) below
ground.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  7

                                                                                
Station ID: 8447241                         PUBLICATION DATE:  04/21/2003
Name:       SESUIT HARBOR, EAST DENNIS                        
            MA
NOAA Chart: 13246                           Latitude:   41° 45.1' N (  41.75170)
USGS Quad:  DENNIS                          Longitude:  70°  9.3' W ( -70.15500)


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


                         BENCH MARK STAMPING:   
                         DESIGNATION:          844 7241 TIDAL 1
                         ALIAS:                NO STAMPING 1

MONUMENTATION:           Survey disk                           VM#:        12480
AGENCY:                  US Army Corps of Engineers (USE)      IDB PID#:        
SETTING CLASSIFICATION:  Concrete base                         OPUS PID:        
LATITUDE:   41° 45.1' N (  41.75170)          LONGITUDE:  70°  9.3' W ( -70.15500)


The bench mark is a disk set in a flagpole base at the NE end of Northside
Marina, 15.64 m (51.3 ft) SE of the southern fuel pump, 5.58 m (18.3 ft) north
of the east end of the concrete seawall, and 0.30 m (1.0 ft) west of the
flagpole.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of  7

                                                                                
Station ID: 8447241                         PUBLICATION DATE:  04/21/2003
Name:       SESUIT HARBOR, EAST DENNIS                        
            MA
NOAA Chart: 13246                           Latitude:   41° 45.1' N (  41.75170)
USGS Quad:  DENNIS                          Longitude:  70°  9.3' W ( -70.15500)


                            T I D A L   D A T U M S 


Tidal datums at SESUIT HARBOR, EAST DENNIS based on:

     LENGTH OF SERIES:      3 Months
     TIME PERIOD:           May 1993 - July 1993
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8443970 BOSTON, BOSTON HARBOR


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

     MEAN HIGHER HIGH WATER                     MHHW   =  3.190
     MEAN HIGH WATER                            MHW    =  3.051
     MEAN SEA LEVEL                             MSL    =  1.593
     MEAN TIDE LEVEL                            MTL    =  1.568
     MEAN LOW WATER                             MLW    =  0.084
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     7241 A 1993                                 4.928    1.877
     7241 B 1993                                 4.752    1.701
     7241 C 1993                                 6.497    3.446
     7241 D 1993                                 6.406    3.355
     D 1974                                      9.088    6.037
     139G                                       10.782    7.731
     844 7241 TIDAL 1                            4.112    1.061


                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  7 of  7

                                                                                
Station ID: 8447241                         PUBLICATION DATE:  04/21/2003
Name:       SESUIT HARBOR, EAST DENNIS                        
            MA
NOAA Chart: 13246                           Latitude:   41° 45.1' N (  41.75170)
USGS Quad:  DENNIS                          Longitude:  70°  9.3' W ( -70.15500)


                             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.