U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  8

                                                                                
Station ID: 8454000                         PUBLICATION DATE:  04/21/2003
Name:       PROVIDENCE, PROVIDENCE RIVER                      
            RI
NOAA Chart: 13224                           Latitude:   41° 48.4' N (  41.80670)
USGS Quad:  PROVIDENCE                      Longitude:  71° 24.1' W ( -71.40170)


To reach the tidal bench marks from northbound I-95 take Exit 18 (Thurbers
Avenue) to Allens Avenue (Alt 1).  Proceed north on Allens Avenue for 0.6 km
(0.4 mi) to 242 Allens Avenue, Promet Corp. Pier, formerly State Pier.  From
southbound I-95 take Exit 19 (Allens Avenue).   Proceed south for 0.3 km (0.2
mi) to Promet Marine Services.  The tide station is located on the pier in the
SE corner of the Promet property.  All bench marks are located within 1.6 km (1
mi) of  tide station.


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


                 PRIMARY BENCH MARK STAMPING:  NO 6 RESET 1930
                         DESIGNATION:          845 4000 TIDAL 6 RESET

MONUMENTATION:           Tidal Station disk                    VM#:          229
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  LW0150
SETTING CLASSIFICATION:  Concrete bulkhead deck                OPUS PID:        
LATITUDE:   41° 48.4' N (  41.80714)          LONGITUDE:  71° 24.0' W ( -71.40081)


The primary bench mark is a disk set in the concrete deck at the onshore end of
the pier, located in the vicinity of the Promet Marine Services Building, 9.00 m
(29.5 ft) west of the SW corner of the building, 4.10 m (13.5 ft) east of a fire
main, and 1.10 m (3.6 ft) south of a 10-inch steam main.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  8

                                                                                
Station ID: 8454000                         PUBLICATION DATE:  04/21/2003
Name:       PROVIDENCE, PROVIDENCE RIVER                      
            RI
NOAA Chart: 13224                           Latitude:   41° 48.4' N (  41.80670)
USGS Quad:  PROVIDENCE                      Longitude:  71° 24.1' W ( -71.40170)


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


                         BENCH MARK STAMPING:  9 1938
                         DESIGNATION:          845 4000 TIDAL 9

MONUMENTATION:           Tidal Station disk                    VM#:          230
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  LW0154
SETTING CLASSIFICATION:  Concrete bulkhead deck                OPUS PID#: LW0154
LATITUDE:   41° 48.5' N (  41.80761)          LONGITUDE:  71° 23.9' W ( -71.39892)


The bench mark is set in the concrete pier deck, located in the vicinity of the
extreme SE end of the Promet Marine Services Pier, 23.60 m (77.4 ft) SW of the
rectangular flood light tower, 0.80 m (2.6 ft) west of the easterly mooring bit,
and 0.20 m (0.7 ft) north of the south cap log.



                         BENCH MARK STAMPING:  10 1938
                         DESIGNATION:          854 4000 TIDAL 10

MONUMENTATION:           Tidal Station disk                    VM#:          231
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  LW0152
SETTING CLASSIFICATION:  Concrete bulkhead extension           OPUS PID:        
LATITUDE:   41° 48.4' N (  41.80742)          LONGITUDE:  71° 24.1' W ( -71.40111)


The bench mark is a disk set in the concrete extension of the pier, located on
the Promet Marine Service property, 32.0 m (105 ft) NW of the NW corner of the
Promet office, 23.60 m (77.4 ft) west of the inshore end of pier, and 9.00 m
(29.5 ft) north of the extended centerline of the pier.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  8

                                                                                
Station ID: 8454000                         PUBLICATION DATE:  04/21/2003
Name:       PROVIDENCE, PROVIDENCE RIVER                      
            RI
NOAA Chart: 13224                           Latitude:   41° 48.4' N (  41.80670)
USGS Quad:  PROVIDENCE                      Longitude:  71° 24.1' W ( -71.40170)


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


                         BENCH MARK STAMPING:  4000 A 1979
                         DESIGNATION:          845 4000 A TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:          232
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  LW5204
SETTING CLASSIFICATION:  Concrete scale platform               OPUS PID:        
LATITUDE:   41° 48.4' N (  41.80703)          LONGITUDE:  71° 24.2' W ( -71.40294)


The bench mark is a disk set in the SW corner of the truck scale platform,
located in the vicinity of the south entrance to Promet Marine Services, 28.00 m
(91.9 ft) north of the north gate post of the south entrance, 6.60 m (21.7 ft)
east of the eastern curb of Allens Avenue, and 1.00 m (3.2 ft) SE of the SE
corner of the truck scale building.



                         BENCH MARK STAMPING:  4000 B 1979
                         DESIGNATION:          845 4000 B

MONUMENTATION:           Tidal Station disk                    VM#:          233
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete step                         OPUS PID:        
LATITUDE:   41° 48.5' N (  41.80808)          LONGITUDE:  71° 24.2' W ( -71.40378)


The bench mark is a disk set in the bottom step of the Narragansett Improvement
Company located at 223 Allens Avenue, 10.10 m (33.1 ft) south of the centerline
of Public Street, 4.00 m (13.1 ft) north of the SE corner of the building, 2.70
m (8.9 ft) west of the west curb of Allens Avenue, and 0.15 m (0.5 ft) above the
sidewalk.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  8

                                                                                
Station ID: 8454000                         PUBLICATION DATE:  04/21/2003
Name:       PROVIDENCE, PROVIDENCE RIVER                      
            RI
NOAA Chart: 13224                           Latitude:   41° 48.4' N (  41.80670)
USGS Quad:  PROVIDENCE                      Longitude:  71° 24.1' W ( -71.40170)


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


                         BENCH MARK STAMPING:  4000 G 1976
                         DESIGNATION:          845 4000 G TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:          234
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AH9453
SETTING CLASSIFICATION:  Concrete loading ramp                 OPUS PID:        
LATITUDE:   41° 48.5' N (  41.80753)          LONGITUDE:  71° 25.0' W ( -71.41661)


The bench mark is a disk set in the top of the concrete loading ramp,  located
on the Promet Marine Service property, 16.00 m (52.5 ft) south of the northern
wharf face, 10.2 m (33.5 ft) west of the NE corner of the warehouse, 3.00 m (9.8
ft) NE of the loading ramp door, and 1.00 m (3.3 ft) above ground.



                         BENCH MARK STAMPING:  4000 K 1977
                         DESIGNATION:          845 4000 K TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:          235
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  LW5205
SETTING CLASSIFICATION:  Concrete pier deck                    OPUS PID:        
LATITUDE:   41° 48.4' N (  41.80703)          LONGITUDE:  71° 24.0' W ( -71.40061)


The bench mark is a disk set in the deck of the concrete pier, located in the SE
corner of the Promet Marine Service Pier, 20.00 m (65.6 ft) south of the SE
corner of the Promet building, 1.50 m (4.9 ft) west of the NOAA 6-inch PVC
protective well, and 0.85 m (2.79 ft) north of the south face of pier.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  8

                                                                                
Station ID: 8454000                         PUBLICATION DATE:  04/21/2003
Name:       PROVIDENCE, PROVIDENCE RIVER                      
            RI
NOAA Chart: 13224                           Latitude:   41° 48.4' N (  41.80670)
USGS Quad:  PROVIDENCE                      Longitude:  71° 24.1' W ( -71.40170)


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


                         BENCH MARK STAMPING:  4000 L 1986
                         DESIGNATION:          845 4000 L

MONUMENTATION:           Tidal Station disk                    VM#:         1519
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   41° 48.5' N (  41.80759)          LONGITUDE:  71° 24.2' W ( -71.40321)


The bench mark is a disk, located along Allens Avenue at the entrance to the
Promet Marine Services property, 48.30 m (158.5 ft) north of the NW corner of
the truck scale, 6.10 m (20.0 ft) east of Power Pole No. 537035, 0.90 m (3.0 ft)
north of the north gate post, and 0.40 m (1.3 ft) NE of a witness post. The
bench mark is crimped to a stainless steel rod driven 15.8 m (52 ft) to refusal,
and encased in a 6 inch PVC pipe with concrete kickblock.



                         BENCH MARK STAMPING:  4000 M 1990
                         DESIGNATION:          845 4000 M

MONUMENTATION:           Tidal Station disk                    VM#:         1520
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   41° 48.5' N (  41.80792)          LONGITUDE:  71° 24.2' W ( -71.40286)


At Providence, near the junction of Allens Avenue and Bay Street, the bench mark
is a disk located on the north side of Promet Marine Services, 12.20 m (40.03
ft) east of the SW corner of the Michelin-Dunlap Tire Company, 4.7 m (15.4 ft)
south of the east side of the Michelin-Dunlap garage door, 0.95 m (3.12 ft) east
of the south end of the ramp leading to the Michelin-Dunlap garage door, and
0.50 m (1.64 ft) south of a witness post. The bench mark is crimped to a
stainless steel rod driven 20.7 m (67.9 ft) to refusal, and encased in a
standard nos concrete kickblock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of  8

                                                                                
Station ID: 8454000                         PUBLICATION DATE:  04/21/2003
Name:       PROVIDENCE, PROVIDENCE RIVER                      
            RI
NOAA Chart: 13224                           Latitude:   41° 48.4' N (  41.80670)
USGS Quad:  PROVIDENCE                      Longitude:  71° 24.1' W ( -71.40170)


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


                         BENCH MARK STAMPING:  4000 N 1990
                         DESIGNATION:          845 4000 N

MONUMENTATION:           Tidal Station disk                    VM#:         1521
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   41° 48.4' N (  41.80661)          LONGITUDE:  71° 24.2' W ( -71.40275)


The bench mark is a disk located in the SW corner of the Promet Marine Services
property, 19.20 m (63.0 ft) south of the centerline of the road leading into the
Promet property, 16.90 m (55.4 ft) east of the centerline of Allens Avenue, 4.90
m (16.1 ft) east of the SW corner of the fence, 2.60 m (8.5 ft) south of a
utility pole, and 0.06 m (0.2 ft) north of a chainlink fence.  The bench mark is
crimped to a stainless steel rod driven 18.3 m (60 ft) to refusal, and encased
in a standard NOS concrete kickblock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  7 of  8

                                                                                
Station ID: 8454000                         PUBLICATION DATE:  04/21/2003
Name:       PROVIDENCE, PROVIDENCE RIVER                      
            RI
NOAA Chart: 13224                           Latitude:   41° 48.4' N (  41.80670)
USGS Quad:  PROVIDENCE                      Longitude:  71° 24.1' W ( -71.40170)


                            T I D A L   D A T U M S 


Tidal datums at PROVIDENCE, PROVIDENCE RIVER based on:

     LENGTH OF SERIES:      19 Years
     TIME PERIOD:           January 1983 - December 2001
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:   


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

     HIGHEST OBSERVED WATER LEVEL (09/21/1938)         =  5.337
     MEAN HIGHER HIGH WATER                     MHHW   =  1.476
     MEAN HIGH WATER                            MHW    =  1.401
     North American Vertical Datum              NAVD88 =  0.754
     MEAN TIDE LEVEL                            MTL    =  0.728
     MEAN SEA LEVEL                             MSL    =  0.686
     MEAN LOW WATER                             MLW    =  0.055
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (01/05/1959)         = -1.094

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     NO 6 RESET 1930                             3.429    2.029
     9 1938                                      3.410    2.010
     10 1938                                     3.213    1.812
     4000 A 1979                                 4.655    3.255
     4000 B 1979                                 4.166    2.765
     4000 G 1976                                 4.394    2.994
     4000 K 1977                                 3.429    2.028
     4000 L 1986                                 4.212    2.811
     4000 M 1990                                 3.754    2.354
     4000 N 1990                                 4.556    3.156


                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  8 of  8

                                                                                
Station ID: 8454000                         PUBLICATION DATE:  04/21/2003
Name:       PROVIDENCE, PROVIDENCE RIVER                      
            RI
NOAA Chart: 13224                           Latitude:   41° 48.4' N (  41.80670)
USGS Quad:  PROVIDENCE                      Longitude:  71° 24.1' W ( -71.40170)


                             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.