U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
PUBLICATION DATE: 10/27/2000
Station ID: 8454538 SUPERCEDED DATE: 04/21/2003
Name: WICKFORD, NARRAGANSETT BAY
RHODE ISLAND
NOAA Chart: 13223 Latitude: 41° 34.3' N
USGS Quad: WICKFORD Longitude: 71° 26.7' W
To reach the tidal bench marks from the intersection of Rhode Island Routes 4
and 102, proceed south on Route 102 for 5.2 km (3.2 miles) to Scenic Route 1a
(Brown Street), then left on Brown Street for 0.3 km (0.2 mile) to Main Street,
then right onto Main Street for 0.6 km (0.4 mile) to the Town Dock. The bench
marks are located on the Scenic Route 1a bridge over Wickford Cove, along Brown
Street, and at the Town Dock. The tide gage and staff were located at the NE
corner of the Town Dock.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 4538 A 1994
DESIGNATION: 845 4538 A
MONUMENTATION: Tidal Station disk VM#: 1454
AGENCY: National Ocean Service (NOS) PID:
SETTING CLASSIFICATION: Concrete seawall
The primary bench mark is a disk set in the NE corner of the Town Dock concrete
seawall, 4.69 m (15.4 ft) ESE of the ramp leading to the floating dock, 2.80 m
(9.2 ft) west of the east face of the seawall, and 0.61 m (2.0 ft) south of the
north face of the seawall.
BENCH MARK STAMPING: 4538 B 1994
DESIGNATION: 845 4538 B
MONUMENTATION: Tidal Station disk VM#: 1535
AGENCY: National Ocean Service (NOS) PID:
SETTING CLASSIFICATION: Concrete seawall
The bench mark is a disk set in the southernmost SE corner of the Town Dock
concrete seawall, 14.11 m (46.3 ft) SW of power pole number 3065-3, 5.39 m (17.7
ft) NW of the southernmost corner of the Town Dock, and 2.80 m (9.2 ft) west of
the east face of the dock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
PUBLICATION DATE: 10/27/2000
Station ID: 8454538 SUPERCEDED DATE: 04/21/2003
Name: WICKFORD, NARRAGANSETT BAY
RHODE ISLAND
NOAA Chart: 13223 Latitude: 41° 34.3' N
USGS Quad: WICKFORD Longitude: 71° 26.7' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 4538 C 1994
DESIGNATION: 845 4538 C
MONUMENTATION: Tidal Station disk VM#: 1536
AGENCY: National Ocean Service (NOS) PID:
SETTING CLASSIFICATION: Granite stairway entrance
The bench mark is a disk set in a granite stairway entrance to the basement of
the house at 7 Main Street, 19.99 m (65.6 ft) NE of the centerline of Main
Street, 13.90 m (45.6 ft) WNW of power pole number 1087, and 2.71 m (8.9 ft)
north of the north curb of Main Street.
BENCH MARK STAMPING: 4538 D 1994
DESIGNATION: 845 4538 D
MONUMENTATION: Tidal Station disk VM#: 1537
AGENCY: National Ocean Service (NOS) PID:
SETTING CLASSIFICATION: Bridge pavement
The bench mark is a disk set in the sidewalk on the east side of Wickford Bridge
number 10 on Brown Street (Route 1A), 11.19 m (36.7 ft) east of the centerline
of Brown Street, 10.49 m (34.4 ft) NNE of power pole number 3, and 7.71 m (25.3
ft) south of the NE end of the concrete bridge railing.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
PUBLICATION DATE: 10/27/2000
Station ID: 8454538 SUPERCEDED DATE: 04/21/2003
Name: WICKFORD, NARRAGANSETT BAY
RHODE ISLAND
NOAA Chart: 13223 Latitude: 41° 34.3' N
USGS Quad: WICKFORD Longitude: 71° 26.7' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 388
DESIGNATION: RIDOT 388
MONUMENTATION: Bench Mark disk VM#: 1538
AGENCY: Rhode Island Department Of Transportation
(RIDOT) PID:
SETTING CLASSIFICATION: Bridge abutment
The bench mark is a disk set in the SW concrete bridge abutment of the Clarence
L. Hussy Bridge number 11 on Route 1A located SE of the intersection of Route
102 and Route 1A, 6.71 m (22.0 ft) west of the SW light pole of the bridge, 5.30
m (17.4 ft) SW of the centerline of Route 1A, and 2.41 m (7.9 ft) ENE of power
pole number 1379-2.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
PUBLICATION DATE: 10/27/2000
Station ID: 8454538 SUPERCEDED DATE: 04/21/2003
Name: WICKFORD, NARRAGANSETT BAY
RHODE ISLAND
NOAA Chart: 13223 Latitude: 41° 34.3' N
USGS Quad: WICKFORD Longitude: 71° 26.7' W
T I D A L D A T U M S
Tidal datums at WICKFORD, NARRAGANSETT BAY based on:
LENGTH OF SERIES: 4 MONTHS
TIME PERIOD: June 1994 - September 1994
TIDAL EPOCH: 1960-1978
CONTROL TIDE STATION: 8454000 PROVIDENCE, PROVIDENCE RIVER
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 1.281
MEAN HIGH WATER MHW = 1.202
MEAN TIDE LEVEL MTL = 0.624
MEAN SEA LEVEL MSL = 0.578
MEAN LOW WATER MLW = 0.045
MEAN LOWER LOW WATER MLLW = 0.000
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
4538 A 1994 1.899 0.697
4538 B 1994 1.906 0.704
4538 C 1994 2.940 1.738
4538 D 1994 2.480 1.278
388 3.526 2.324
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
PUBLICATION DATE: 10/27/2000
Station ID: 8454538 SUPERCEDED DATE: 04/21/2003
Name: WICKFORD, NARRAGANSETT BAY
RHODE ISLAND
NOAA Chart: 13223 Latitude: 41° 34.3' N
USGS Quad: WICKFORD Longitude: 71° 26.7' 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.