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

                                                                                
Station ID: 8454049                         PUBLICATION DATE:  06/03/2020
Name:       QUONSET POINT                                     
            RI
NOAA Chart: 13221                           Latitude:   41° 35.2' N (  41.58680)
USGS Quad:  WICKFORD                        Longitude:  71° 24.7' W ( -71.41100)


To reach the tide station from North Kingstown, RI, proceed to the intersection
of U.S. Route 1 north and Roger Williams Way, turn right (east) onto Roger
WIlliams Way and proceed 4.3 km (2.7 mi) to the entrance of the American
Shipyard Corporation.  The tide station is located on the offshore end of the
pier on a round concrete docking cell.  The tidal bench marks are along the pier
and just outside the American Shipyard property.


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


                 PRIMARY BENCH MARK STAMPING:  4049 D 1999
                         DESIGNATION:          845 4049 D

MONUMENTATION:           Tidal Station disk                    VM#:        16009
AGENCY:                  National Ocean Service (NOS)          IDB PID:         
SETTING CLASSIFICATION:  Concrete pier                         OPUS PID#: BBDK64
LATITUDE:   41° 35.2' N (  41.58678)          LONGITUDE:  71° 24.7' W ( -71.41089)


The primary bench mark is a disk set in the south side of the pier at the
American Shipyards Dock in a concrete cap on the seventh yellow bollard from the
end, 23.80 m (78.1 ft) south of the north edge of the pier, 0.66 m (2.2 ft) east
of the center of the bollard, and 0.55 m (1.8 ft) north of the south edge of the
pier on the east side of the bollard.

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

                                                                                
Station ID: 8454049                         PUBLICATION DATE:  06/03/2020
Name:       QUONSET POINT                                     
            RI
NOAA Chart: 13221                           Latitude:   41° 35.2' N (  41.58680)
USGS Quad:  WICKFORD                        Longitude:  71° 24.7' W ( -71.41100)


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


                         BENCH MARK STAMPING:  4049 A 1999
                         DESIGNATION:          845 4049 A

MONUMENTATION:           Tidal Station disk                    VM#:        16010
AGENCY:                  National Ocean Service (NOS)          IDB PID:         
SETTING CLASSIFICATION:  Concrete pier                         OPUS PID:        
LATITUDE:   41° 35.2' N (  41.58592)          LONGITUDE:  71° 24.4' W ( -71.40719)


The bench mark is a disk set in a concrete cap of a large metal cleat at the
American Shipyards Dock on the SW side of a round concrete docking cell, 3.84 m
(12.6 ft) west of a double bollard, 3.70 m (12.1 ft) south of the center of the
catwalk to the cell, and 1.05 m (3.4 ft) east of the edge of the cell.



                         BENCH MARK STAMPING:  4049 E 1999
                         DESIGNATION:          845 4049 E

MONUMENTATION:           Tidal Station disk                    VM#:        16013
AGENCY:                  National Ocean Service (NOS)          IDB PID:         
SETTING CLASSIFICATION:  Concrete slab                         OPUS PID#: BBDH88
LATITUDE:   41° 35.3' N (  41.58756)          LONGITUDE:  71° 24.8' W ( -71.41253)


The bench mark is a disk set in the SE corner of the 2.40 m x 2.40 m (7.9 ft x
7.9 ft) concrete foundation for an electrical transformer at the American
Shipyards Dock, 35.15 m (115.3 ft) NNE of the intersection of Roger Williams Way
and Zarbo Avenue, 18.20 m (59.7 ft) north of the north post for the gate to the
American Shipyards Corporation, and 10.90 m (35.8 ft) south of the centerline of
Zarbo Avenue.

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

                                                                                
Station ID: 8454049                         PUBLICATION DATE:  06/03/2020
Name:       QUONSET POINT                                     
            RI
NOAA Chart: 13221                           Latitude:   41° 35.2' N (  41.58680)
USGS Quad:  WICKFORD                        Longitude:  71° 24.7' W ( -71.41100)


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


                         BENCH MARK STAMPING:  4049 F 2013
                         DESIGNATION:          845 4049 F

MONUMENTATION:           Flange-encased Rod                    VM#:        21087
AGENCY:                  National Ocean Service                IDB PID:         
SETTING CLASSIFICATION:  Stainless steel rod in sleeve         OPUS PID:        
LATITUDE:   41° 35.2' N (  41.58717)          LONGITUDE:  71° 25.0' W ( -71.41631)


The benchmark is a stainless steel rod 91.53 m (300.3 ft) South of South large
boulder at parking lot entrance near roger williams parkway, 43.98 m (144.3 ft)
West of the North concrete column surrounding trashcans on South end of
turnaround, and 28.19 m (92.5 ft) East of the fenced property line for the
adjacent general dynamics manufacturing facility. The datum point is the top of
a stainless steel rod driven 75.1 ft (22.9 m) to refusal, in a sleeve extending
to a depth of 1.00 m (3.28 ft), and encased in a 5- inch nos logo cap, with
concrete kick block.



                         BENCH MARK STAMPING:  4049 G 2017
                         DESIGNATION:          845 4049 G

MONUMENTATION:           Tidal Station disk                    VM#:        22471
AGENCY:                  National Ocean Service (NOS)          IDB PID:         
SETTING CLASSIFICATION:  Concrete seawall                      OPUS PID:        
LATITUDE:   41° 35.3' N (  41.58753)          LONGITUDE:  71° 24.7' W ( -71.41139)


The bench mark is a disk set on the northern seawall of the Senesco Marine
Shipyards Dock at the NE most extent of the property near the fenceline, 53.26m
(174.77 ft) east of the center of the SE support column for the Senesco Marine
office building, 0.72m (2.35 ft) south of the eastern end of fencline along the
NE side of the property, and 0.63m (2.07 ft) north of the south edge of the sea
wall.

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

                                                                                
Station ID: 8454049                         PUBLICATION DATE:  06/03/2020
Name:       QUONSET POINT                                     
            RI
NOAA Chart: 13221                           Latitude:   41° 35.2' N (  41.58680)
USGS Quad:  WICKFORD                        Longitude:  71° 24.7' W ( -71.41100)


                            T I D A L   D A T U M S 


Tidal datums at QUONSET POINT based on:

     LENGTH OF SERIES:      18 YEARS
     TIME PERIOD:           6/00-5/12, 11/12-10/14, 3/15-2/19
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8452660 NEWPORT, NARRAGANSETT BAY


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

     HIGHEST OBSERVED WATER LEVEL (04/16/2007)         =  2.231
     MEAN HIGHER HIGH WATER                     MHHW   =  1.251
     MEAN HIGH WATER                            MHW    =  1.176
     North American Vertical Datum              NAVD88 =  0.680
     MEAN TIDE LEVEL                            MTL    =  0.612
     MEAN SEA LEVEL                             MSL    =  0.567
     MEAN LOW WATER                             MLW    =  0.047
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (02/11/2001)         = -0.832

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     4049 D 1999                                 2.985    1.809
     4049 A 1999                                 2.930    1.754
     4049 E 1999                                 3.021    1.845
     4049 F 2013                                 2.810    1.634
     4049 G 2017                                 2.808    1.632


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

                                                                                
Station ID: 8454049                         PUBLICATION DATE:  06/03/2020
Name:       QUONSET POINT                                     
            RI
NOAA Chart: 13221                           Latitude:   41° 35.2' N (  41.58680)
USGS Quad:  WICKFORD                        Longitude:  71° 24.7' W ( -71.41100)


                             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.