U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
PUBLICATION DATE: 11/25/1985
Station ID: 8454000 SUPERCEDED DATE: 04/21/2003
Name: PROVIDENCE, PROVIDENCE RIVER
RHODE ISLAND
NOAA Chart: 13224 Latitude: 41° 48.4' N
USGS Quad: PROVIDENCE Longitude: 71° 24.1' W
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 0.4 mile
(0.6 km) to 242 Allens Avenue, Promet Corp. Pier, formerly State Pier. From
southbound I-95 take Exit 19 (Allens Avenue), proceed on Allens Avenue south for
0.2 mile (0.3 m) to Promet Corp. Pier. The tide station is located on the pier
and the bench marks within 1 mile (1.6 km) radius of the 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
MONUMENTATION: Survey Disk VM#: 229
AGENCY: PID#: LW0150
SETTING CLASSIFICATION: Concrete Retaining Wall
The bench mark is located in the vicinity of Promet Corp. Building, 29 feet (9
m) west of the SW corner of the building, 13 feet (4 m) east of fire main, and
3.5 feet (1.1 m) south of 10-inch steam main. The bench mark is set in the
concrete retaining wall onshore end of the pier.
BENCH MARK STAMPING: 9 1938
MONUMENTATION: Survey Disk VM#: 230
AGENCY: PID#: LW0154
SETTING CLASSIFICATION: Concrete Pier Floor
The bench mark is located on the south side of Promet Corp. Pier, approximately
2.5 feet (0.8 m) west of the most easterly mooning bitt, and approximately 0.5
foot (0.2 m) north of south cap log. The bench mark is set in the concrete
floor.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
PUBLICATION DATE: 11/25/1985
Station ID: 8454000 SUPERCEDED DATE: 04/21/2003
Name: PROVIDENCE, PROVIDENCE RIVER
RHODE ISLAND
NOAA Chart: 13224 Latitude: 41° 48.4' N
USGS Quad: PROVIDENCE Longitude: 71° 24.1' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 10 1938
MONUMENTATION: Survey Disk VM#: 231
AGENCY: PID#: LW0152
SETTING CLASSIFICATION: Concrete Extension of Bulkhead
The bench mark is located in the Promet Corp. compound, 105 feet (32 m) NW of
the NW corner of the building, 77.5 feet (23.6 m) west of inshore end of pier,
28 feet (9 m) north of extended centerline of pier, and 3.8 feet (1.2 m) SW of
3-inch water main. The bench mark is set in concrete extension of bulkhead.
BENCH MARK STAMPING: 4000 A 1979
MONUMENTATION: Survey Disk VM#: 232
AGENCY: PID#: LW5204
SETTING CLASSIFICATION: Concrete Platform
The bench mark is located in the vicinity of the south entrance to Promet Corp.
compound, 92.0 feet (28.0 m) north of the north gate post of the south entrance,
21.7 feet (6.6 m) east of the eastern curb of Allens Avenue and 3.2 feet (1.0 m)
NE of the SE corner of the truck scale building. The bench mark is set in the
SW corner of the scale platform.
BENCH MARK STAMPING: 4000 B 1979
MONUMENTATION: Survey Disk VM#: 233
AGENCY: PID:
SETTING CLASSIFICATION: Concrete Steps
The bench mark is located at 223 Allens Avenue (Narragansett Improvement Co.),
33.0 feet (10.1 m) south of the centerline of Public Street, 13.2 feet (4.0 m)
north of the SE corner of the building and 9.0 feet (2.7 m) west of the west
curb of Allens Avenue. The bench mark is set in the bottom step.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
PUBLICATION DATE: 11/25/1985
Station ID: 8454000 SUPERCEDED DATE: 04/21/2003
Name: PROVIDENCE, PROVIDENCE RIVER
RHODE ISLAND
NOAA Chart: 13224 Latitude: 41° 48.4' N
USGS Quad: PROVIDENCE Longitude: 71° 24.1' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 4000 G 1976
MONUMENTATION: Survey Disk VM#: 234
AGENCY: PID#: AH9453
SETTING CLASSIFICATION: Concrete Platform
The bench mark is located in the Promet Corp. compound, 57 feet (17 m) south of
the SE leg of the most northerly loading chute, 54 feet (16 m) west of the
eastern wharf face, 33.3 feet (10.2 m) north of the SE corner of the warehouse,
and 9.7 feet (3.0 m) SE from the loading ramp door. The bench mark is set in
the top of a concrete loading platform, 3.2 feet (1.0 m) above ground.
BENCH MARK STAMPING: 4000 K 1977
MONUMENTATION: Survey Disk VM#: 235
AGENCY: PID#: LW5205
SETTING CLASSIFICATION: Concrete Dock
The bench mark is located in the SE corner of the Promet Corp. dock, 65.6 feet
(20.0 m) south of the SE corner of the Promet Corp. building, 15.3 feet (4.7 m)
south of tide staff, and 2 feet (1 m) north of the south end of the dock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
PUBLICATION DATE: 11/25/1985
Station ID: 8454000 SUPERCEDED DATE: 04/21/2003
Name: PROVIDENCE, PROVIDENCE RIVER
RHODE ISLAND
NOAA Chart: 13224 Latitude: 41° 48.4' N
USGS Quad: PROVIDENCE Longitude: 71° 24.1' W
T I D A L D A T U M S
Tidal datums at PROVIDENCE, PROVIDENCE RIVER based on:
LENGTH OF SERIES: 18 YEARS
TIME PERIOD: 1960-1978
TIDAL EPOCH: 1960-1978
CONTROL TIDE STATION:
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in FEET:
HIGHEST OBSERVED WATER LEVEL (09/21/1938) = 17.71
MEAN HIGHER HIGH WATER MHHW = 4.96
MEAN HIGH WATER MHW = 4.70
MEAN TIDE LEVEL MTL = 2.44
* NATIONAL GEODETIC VERTICAL DATUM NGVD29 = 1.85
MEAN LOW WATER MLW = 0.18
MEAN LOWER LOW WATER MLLW = 0.00
LOWEST OBSERVED WATER LEVEL (01/05/1959) = -3.39
* NGVD reference based on elevations published in Quad 410711, 1970, and NOS
leveling of 1985.
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In FEET above:
Stamping or Designation MLLW MHW
NO 6 RESET 1930 11.45 6.75
9 1938 11.39 6.69
10 1938 10.78 6.08
4000 A 1979 15.55 10.85
4000 B 1979 13.93 9.23
4000 G 1976 14.61 9.91
4000 K 1977 11.44 6.74
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
PUBLICATION DATE: 11/25/1985
Station ID: 8454000 SUPERCEDED DATE: 04/21/2003
Name: PROVIDENCE, PROVIDENCE RIVER
RHODE ISLAND
NOAA Chart: 13224 Latitude: 41° 48.4' N
USGS Quad: PROVIDENCE Longitude: 71° 24.1' W
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 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.