U.S. DEPARTMENT OF COMMERCE
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National Ocean Service
Datums Page Page 1 of 8
Station ID: 8574070 PUBLICATION DATE: 05/29/2009
Name: HAVRE DE GRACE, CHESAPEAKE BAY
MD
NOAA Chart: 12274 Latitude: 39° 32.2' N ( 39.53670)
USGS Quad: HAVRE DE GRACE Longitude: 76° 5.4' W ( -76.09000)
To reach the tidal bench marks from the junction of U.S. Highway 40 and State
Highway 7 proceed east on State Highway 7 for 0.8 km (0.5 mi) to Union Avenue,
continue south on Union Avenue for 1.6 km (1.0 mi) to Commerce Street, turn left
on Commerce Street and proceed 0.24 km (0.15 mi) to Yacht Basin Street. The
bench marks are located in the marina, city park, and along Union Avenue. The
tide station was located in the city marina.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: NO 5 1938
DESIGNATION: 857 4070 TIDAL 5
MONUMENTATION: Tidal Station disk VM#: 419
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: JV0013
SETTING CLASSIFICATION: Step OPUS PID:
LATITUDE: 39° 32.3' N ( 39.53830) LONGITUDE: 76° 5.4' W ( -76.09000)
The primary bench mark is a disk set flush in the lower step on the west face of
the Veterans Monument in the city park at the city marina, 49.38 m (162.0 ft)
south of the centerline of Commerce Street, 5.49 m (18.0 ft) west of the most
easterly flagpole, 2.44 m (8.0 ft) east of the most westerly flagpole, and 0.3 m
(1 ft) above ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 8
Station ID: 8574070 PUBLICATION DATE: 05/29/2009
Name: HAVRE DE GRACE, CHESAPEAKE BAY
MD
NOAA Chart: 12274 Latitude: 39° 32.2' N ( 39.53670)
USGS Quad: HAVRE DE GRACE Longitude: 76° 5.4' W ( -76.09000)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 1 1927
DESIGNATION: 857 4070 TIDAL 1
MONUMENTATION: Tidal Station disk VM#: 420
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: JV0015
SETTING CLASSIFICATION: Stone masonry retaining wall OPUS PID:
LATITUDE: 39° 33.2' N ( 39.55330) LONGITUDE: 76° 5.6' W ( -76.09330)
The bench mark is a disk set in the top of the stone masonry retaining wall of
the railroad tunnel near the intersection of Otsego Street and Union Avenue,
32.31 m (106.0 ft) west of the east end of the wall, 15.54 m (51.0 ft) east of
the west end of the wall, 10.79 m (35.4 ft) SSW of the centerline of Otsego
Street, 8.47 m (27.8 ft) WSW of power pole G&E 70627, 0.39 m (1.3 ft) south of
the north face of the wall, and 1.16 m (3.8 ft) above ground level.
BENCH MARK STAMPING: 2 1927
DESIGNATION: 857 4070 TIDAL 2
MONUMENTATION: Tidal Station disk VM#: 421
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: JV0016
SETTING CLASSIFICATION: Stone masonry retaining wall OPUS PID:
LATITUDE: 39° 33.1' N ( 39.55170) LONGITUDE: 76° 5.6' W ( -76.09330)
The bench mark is a disk set in the top of the stone masonry retaining wall of
the railroad tunnel near the intersection of Otsego Street and Union Avenue,
19.39 m (63.6 ft) south of the centerline of Otsego Street, 12.89 m (42.3 ft) SE
of power pole G&E 70632, 3.35 m (11.0 ft) east of the centerline of the road
through the tunnel, 0.39 m (1.3 ft) south of the north face of the masonry wall,
0.30 m (1.0 ft) east of the west face of the wall, and 0.76 m (2.5 ft) above
ground level.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 8
Station ID: 8574070 PUBLICATION DATE: 05/29/2009
Name: HAVRE DE GRACE, CHESAPEAKE BAY
MD
NOAA Chart: 12274 Latitude: 39° 32.2' N ( 39.53670)
USGS Quad: HAVRE DE GRACE Longitude: 76° 5.4' W ( -76.09000)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: NO 4 1938
DESIGNATION: 857 4070 TIDAL 4
MONUMENTATION: Tidal Station disk VM#: 422
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: JV0011
SETTING CLASSIFICATION: Concrete bulkhead OPUS PID#: JV0011
LATITUDE: 39° 32.3' N ( 39.53830) LONGITUDE: 76° 5.3' W ( -76.08830)
The bench mark is a disk set flush in the top of the concrete bulkhead cap at
the Havre de Grace City Marina, 32.10 m (105.3 ft) SW of the SW corner of the
Marina Snack Bar and Harbor Masters Office, 8.90 m (29.2 ft) NW of the utility
pole bearing inscription 400M Mercury, 8.08 m (26.5 ft) NW of the most SE corner
of the concrete bulkhead, and level with the parking area.
BENCH MARK STAMPING: 4070 A 1977
DESIGNATION: 857 4070 A TIDAL
MONUMENTATION: Tidal Station disk VM#: 423
AGENCY: National Ocean Survey (NOS) IDB PID#: JV6256
SETTING CLASSIFICATION: Concrete retaining wall OPUS PID:
LATITUDE: 39° 32.3' N ( 39.53830) LONGITUDE: 76° 5.4' W ( -76.09000)
The bench mark is a disk set flush in the west concrete cap of a cellar well
entrance to an octagon-shaped gazebo in the city park, 31.82 m (104.4 ft) south
of the centerline of Commerce Street, 22.30 m (73.0 ft) NW of the NW corner of
the Veterans Monument, 7.65 m (25.1 ft) SSW of the SW face of the gazebo, and
0.06 m (0.2 ft) above ground level. Note: New metal doors have been installed
over top of the bench mark. The mark is still accessible with the doors open.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 8
Station ID: 8574070 PUBLICATION DATE: 05/29/2009
Name: HAVRE DE GRACE, CHESAPEAKE BAY
MD
NOAA Chart: 12274 Latitude: 39° 32.2' N ( 39.53670)
USGS Quad: HAVRE DE GRACE Longitude: 76° 5.4' W ( -76.09000)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 4070 B 1979
DESIGNATION: 857 4070 B TIDAL
MONUMENTATION: Tidal Station disk VM#: 424
AGENCY: National Ocean Survey (NOS) IDB PID#: JV6255
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 39° 32.4' N ( 39.54000) LONGITUDE: 76° 5.5' W ( -76.09170)
The bench mark is a disk located on the NE corner of the intersection of South
Union Avenue and Commerce Street, 23.41 m (76.8 ft) SW of the SW corner of a
two-story brick house, 13.08 m (42.9 ft) north of the centerline of Commerce
Street, 9.51 m (31.2 ft) east of the centerline of South Union Avenue, and 3.90
m (12.8 ft) NNW of a fire hydrant. The bench mark is set 6 cm (0.2 ft) below
ground level, crimped to a stainless steel rod driven 7.32 m (24 ft) to refusal,
and encased in a 4-inch PVC pipe and concrete kickblock.
BENCH MARK STAMPING: 4070 C 1979
DESIGNATION: 857 4070 C TIDAL
MONUMENTATION: Tidal Station disk VM#: 425
AGENCY: National Ocean Survey (NOS) IDB PID#: JV6257
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 39° 32.6' N ( 39.54330) LONGITUDE: 76° 5.5' W ( -76.09170)
The bench mark is a disk located on the SW corner of the intersection of
Revolution Street and South Union Avenue, 37.92 m (124.4 ft) NE of the NE corner
of a parking garage, 13.56 m (44.5 ft) west of the centerline of South Union
Avenue, 11.58 m (38.0 ft) south of the centerline of Revolution Street, and 4.0
m (13.1 ft) west of a traffic signal post. The bench mark is set 3 cm (0.1 ft)
below ground level, crimped to a stainless steel rod driven 11 m (36 ft) below
ground level, and encased in a 4-inch PVC pipe and concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 8
Station ID: 8574070 PUBLICATION DATE: 05/29/2009
Name: HAVRE DE GRACE, CHESAPEAKE BAY
MD
NOAA Chart: 12274 Latitude: 39° 32.2' N ( 39.53670)
USGS Quad: HAVRE DE GRACE Longitude: 76° 5.4' W ( -76.09000)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 4070 D 1979
DESIGNATION: 857 4070 D TIDAL
MONUMENTATION: Tidal Station disk VM#: 426
AGENCY: National Ocean Survey (NOS) IDB PID#: JV6247
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 39° 32.9' N ( 39.54830) LONGITUDE: 76° 5.5' W ( -76.09170)
The bench mark is a disk located on the NW corner of the intersection of South
Union Avenue and Congress Street, 20.27 m (66.5 ft) SE of the SE corner of St.
Johns Episcopalian Church, 8.99 m (29.5 ft) west of the centerline of South
Union Avenue, 8.84 m (29.0 ft) north of the centerline of Congress Street, 2.32
m (7.6 ft) east of the east edge of the sidewalk, and 1.92 m (6.3 ft) SE of a
traffic signal post. The bench mark is set 3 cm (0.1 ft) below ground level,
crimped to a stainless steel rod driven 7.32 m (24 ft) to refusal, and encased
in a 4-inch PVC pipe and concrete kickblock.
BENCH MARK STAMPING: 4070 E 2005
DESIGNATION: 857 4070 E
MONUMENTATION: Tidal Station disk VM#: 17842
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Bulkhead OPUS PID#: BBCC02
LATITUDE: 39° 32.3' N ( 39.53830) LONGITUDE: 76° 5.4' W ( -76.09000)
The bench mark is a disk set flush on the seawall in the Havre De Grace Marina,
39.01 m (128.0 ft) from the SE corner of the western most steps in the park,
32.30 m (106.0 ft) from the western edge of the electrical panel in the middle
of the park, and 2.29 m (7.5 ft) from electrical pole "239781."
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 8
Station ID: 8574070 PUBLICATION DATE: 05/29/2009
Name: HAVRE DE GRACE, CHESAPEAKE BAY
MD
NOAA Chart: 12274 Latitude: 39° 32.2' N ( 39.53670)
USGS Quad: HAVRE DE GRACE Longitude: 76° 5.4' W ( -76.09000)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 4070 F 2005
DESIGNATION: 857 4070 F
MONUMENTATION: Tidal Station disk VM#: 17843
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Bulkhead OPUS PID#: BBBQ09
LATITUDE: 39° 32.3' N ( 39.53830) LONGITUDE: 76° 5.5' W ( -76.09170)
The bench mark is lcoated along the sea wall of the marina, under light pole
"239782", 18.29 m (60.0 ft) west of the edge of an electrical panel on the west
side of Tydings Memorial Park, 60.96 m (200.0 ft) SE of SE corner of Cees
Building on west edge of Tydings Memorial Park, and 4.88 m (16.0 ft) SW of light
pole "464871".
BENCH MARK STAMPING: 4070 G 2005
DESIGNATION: 857 4070 G
MONUMENTATION: Tidal Station disk VM#: 17844
AGENCY: National Ocean Service (NOS) IDB PID#:
SETTING CLASSIFICATION: Bulkhead OPUS PID:
LATITUDE: 39° 32.3' N ( 39.53830) LONGITUDE: 76° 5.3' W ( -76.08830)
The bench mark is a disk set flush in the top of the concrete bulkhead cap on
the eastern side of the Havre De Grace City Marina, 38.40 m (126.0 ft) east of
telephone pole "460684," 31.09 m (102.0 ft) NE of the NE corner of the Marina
Building/snack bar, and 3.81 m (12.5 ft) NE of a small brick gazebo, 0.47 m (1.5
ft) above the sidewalk.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 7 of 8
Station ID: 8574070 PUBLICATION DATE: 05/29/2009
Name: HAVRE DE GRACE, CHESAPEAKE BAY
MD
NOAA Chart: 12274 Latitude: 39° 32.2' N ( 39.53670)
USGS Quad: HAVRE DE GRACE Longitude: 76° 5.4' W ( -76.09000)
T I D A L D A T U M S
Tidal datums at HAVRE DE GRACE, CHESAPEAKE BAY based on:
LENGTH OF SERIES: 13 YEARS
TIME PERIOD: January 1979 - December 1991
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8574680 BALTIMORE, FORT MCHENRY, PATAPSCO RIVER
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
HIGHEST OBSERVED WATER LEVEL (09/06/1979) = 2.086
MEAN HIGHER HIGH WATER MHHW = 0.746
MEAN HIGH WATER MHW = 0.642
MEAN SEA LEVEL MSL = 0.361
MEAN TIDE LEVEL MTL = 0.353
MEAN LOW WATER MLW = 0.064
MEAN LOWER LOW WATER MLLW = 0.000
LOWEST OBSERVED WATER LEVEL (12/25/1980) = -1.261
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
NO 5 1938 7.380 6.738
1 1927 7.453 6.811
2 1927 8.189 7.547
NO 4 1938 1.817 1.175
4070 A 1977 7.416 6.774
4070 B 1979 7.515 6.873
4070 C 1979 10.490 9.848
4070 D 1979 12.534 11.892
4070 E 2005 1.807 1.165
4070 F 2005 1.847 1.205
4070 G 2005 3.020 2.378
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 8 of 8
Station ID: 8574070 PUBLICATION DATE: 05/29/2009
Name: HAVRE DE GRACE, CHESAPEAKE BAY
MD
NOAA Chart: 12274 Latitude: 39° 32.2' N ( 39.53670)
USGS Quad: HAVRE DE GRACE Longitude: 76° 5.4' W ( -76.09000)
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.