U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 7
Station ID: 8574821 PUBLICATION DATE: 12/12/2003
Name: HAWKINS POINT
MD
NOAA Chart: 12281 Latitude: 39° 12.5' N ( 39.20830)
USGS Quad: CURTIS BAY Longitude: 76° 32.0' W ( -76.53330)
To reach the tidal bench marks from the intersection of State Highway 2
(Governor Ritchie Highway) and State Highway 710 (Ordinance Road) in Glen
Burnie, proceed ENE on State Highway 710 for 3.5 km (2.2 mi) to State Highway
170 (Fort Smallwood Road), then turn right and proceed NE on State Highway 170
for 3.1 km (1.9 mi) to Fort Armistead Road, then turn left and proceed NW on
Fort Armistead Road for 1.8 km (1.1 mi), then turn right and continue for 0.2 km
(0.1 mi), then turn left onto a dirt road and go 0.6 km (0.4 mi) to the end of
the road. The bench marks are on the sea wall. The tide gage and staff were on
the city owned pier.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: NO 1 1975
DESIGNATION: 857 4821 TIDAL 1
MONUMENTATION: Tidal Station disk VM#: 3185
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete sea wall OPUS PID:
LATITUDE: 39° 12.5' N ( 39.20831) LONGITUDE: 76° 31.9' W ( -76.53169)
The primary bench mark is a disk set flush in the concrete sea wall at the foot
of the city pier, about 2 m (5 ft) from the north fence gate post, and 0.61 m
(2.0 ft) west of the edge of the sea wall.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 7
Station ID: 8574821 PUBLICATION DATE: 12/12/2003
Name: HAWKINS POINT
MD
NOAA Chart: 12281 Latitude: 39° 12.5' N ( 39.20830)
USGS Quad: CURTIS BAY Longitude: 76° 32.0' W ( -76.53330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING:
DESIGNATION: 857 4821 TIDAL 3
ALIAS: NO STAMPING 1
MONUMENTATION: See descriptive text VM#: 3186
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete sea wall OPUS PID:
LATITUDE: 39° 12.5' N ( 39.20831) LONGITUDE: 76° 31.9' W ( -76.53169)
The bench mark is a chiseled point marked by a white painted circle on the
concrete sea wall, 40 m (130 ft) NNE of bench mark NO 1 1975.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 7
Station ID: 8574821 PUBLICATION DATE: 12/12/2003
Name: HAWKINS POINT
MD
NOAA Chart: 12281 Latitude: 39° 12.5' N ( 39.20830)
USGS Quad: CURTIS BAY Longitude: 76° 32.0' W ( -76.53330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING:
DESIGNATION: 857 4821 TIDAL 4
ALIAS: NO STAMPING 2
MONUMENTATION: Nail VM#: 3187
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Concrete sea wall OPUS PID:
LATITUDE: 39° 12.5' N ( 39.20831) LONGITUDE: 76° 31.9' W ( -76.53169)
The bench mark is a masonry nail driven into the concrete sea wall and marked
"BUCK" with white painted letters, and 30 m (100 ft) north of bench mark 857
4821 TIDAL 3.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 7
Station ID: 8574821 PUBLICATION DATE: 12/12/2003
Name: HAWKINS POINT
MD
NOAA Chart: 12281 Latitude: 39° 12.5' N ( 39.20830)
USGS Quad: CURTIS BAY Longitude: 76° 32.0' W ( -76.53330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING:
DESIGNATION: 857 4821 TIDAL 2
ALIAS: NO STAMPING 3
MONUMENTATION: Nail VM#: 17049
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Pavement OPUS PID:
LATITUDE: 39° 12.5' N ( 39.20831) LONGITUDE: 76° 31.9' W ( -76.53169)
The bench mark is a nail driven into and flush with the pavement at the SE
corner of a tin shed, 15 m (50 ft) SW of bench mark NO 1 1975, 0.3 m (1 ft) from
the SE corner of the tin shed. NOTE: A white painted circle indicates the
location of the nail.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 7
Station ID: 8574821 PUBLICATION DATE: 12/12/2003
Name: HAWKINS POINT
MD
NOAA Chart: 12281 Latitude: 39° 12.5' N ( 39.20830)
USGS Quad: CURTIS BAY Longitude: 76° 32.0' W ( -76.53330)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING:
DESIGNATION: 857 4821 TIDAL 5
ALIAS: NO STAMPING 4
MONUMENTATION: Nail VM#: 17050
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Tree trunk OPUS PID:
LATITUDE: 39° 12.5' N ( 39.20831) LONGITUDE: 76° 31.9' W ( -76.53169)
The bench mark is a nail driven into the SE side of the trunk of a large tree,
67 m (220 ft) NW of bench mark 857 4821 TIDAL 4, 5 m (15 ft) SW of the sea wall,
and 0.3 m (1.0 ft) above the ground.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 7
Station ID: 8574821 PUBLICATION DATE: 12/12/2003
Name: HAWKINS POINT
MD
NOAA Chart: 12281 Latitude: 39° 12.5' N ( 39.20830)
USGS Quad: CURTIS BAY Longitude: 76° 32.0' W ( -76.53330)
T I D A L D A T U M S
Tidal datums at HAWKINS POINT based on:
LENGTH OF SERIES: 1 MONTH
TIME PERIOD: September 1976 - September 1976
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:
MEAN HIGHER HIGH WATER MHHW = 0.524
MEAN HIGH WATER MHW = 0.425
MEAN SEA LEVEL MSL = 0.250
MEAN TIDE LEVEL MTL = 0.244
MEAN LOW WATER MLW = 0.063
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
NO 1 1975 1.635 1.210
857 4821 TIDAL 3 1.609 1.184
857 4821 TIDAL 4 1.652 1.227
857 4821 TIDAL 2 2.182 1.757
857 4821 TIDAL 5 1.992 1.567
Foot Notes:
Bench mark 8574821 TIDAL 5 is based on one differential leveling connection and
does not meet the quality control standards of the NOS. Therefore, caution
should be used when deriving an elevation for this mark.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 7 of 7
Station ID: 8574821 PUBLICATION DATE: 12/12/2003
Name: HAWKINS POINT
MD
NOAA Chart: 12281 Latitude: 39° 12.5' N ( 39.20830)
USGS Quad: CURTIS BAY Longitude: 76° 32.0' W ( -76.53330)
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.