U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 7
Station ID: 8570283 PUBLICATION DATE: 04/28/2020
Name: OCEAN CITY INLET
MD
NOAA Chart: 12211 Latitude: 38° 19.7' N ( 38.32833)
USGS Quad: OCEAN CITY Longitude: 75° 5.5' W ( -75.09167)
To reach the tidal bench marks from the east end of the US Highway 50 bridge and
Philadelphia Avenue in Ocean City, proceed south on Philadelphia Avenue for 0.5
km (0.3 mi) to the intersection with Worchester Street, turn right on Worchester
Street, then left into the US Coast Guard Station. The bench marks are located
on the grounds of the station. The tide gage was located on the westernmost
pier at the boat basin.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 0280 J 1982
DESIGNATION: 857 0283 J TIDAL
MONUMENTATION: Tidal Station disk VM#: 13880
AGENCY: National Ocean Service (NOS) IDB PID#: DL8731
SETTING CLASSIFICATION: Stainless steel rod OPUS PID#: DL8731
LATITUDE: 38° 19.7' N ( 38.32772) LONGITUDE: 75° 5.4' W ( -75.09028)
The primary bench mark is a disk located in the SE corner of the U.S. Coast
Guard station, on the south side of the U.S. Coast Guard Station, 28.47 m (93.4
ft) SE of the east leg of a steel radio tower, 18.99 m (62.3 ft) SSW of the SW
corner of the Coast Guard barracks, 4.63 m (15.2 ft) NNE of the SE corner of a
chain link fence, and 1.31 m (4.3 ft) WSW of the chain link fence. The bench
mark is set 9 cm (0.3 ft) below ground level, crimped to the top of a stainless
steel rod driven an unspecified depth, 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 2 of 7
Station ID: 8570283 PUBLICATION DATE: 04/28/2020
Name: OCEAN CITY INLET
MD
NOAA Chart: 12211 Latitude: 38° 19.7' N ( 38.32833)
USGS Quad: OCEAN CITY Longitude: 75° 5.5' W ( -75.09167)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 0280 H 1980
DESIGNATION: 857 0283 H
MONUMENTATION: Tidal Station disk VM#: 13879
AGENCY: National Ocean Service (NOS) IDB PID:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 38° 19.7' N ( 38.32856) LONGITUDE: 75° 5.4' W ( -75.08986)
The bench mark is located on the north side of the coast guard station at
Worchester street and Philadelphia avenue near the entrance to the base, 21.27 m
(69.78 ft) ESE of a white hydrant, 8.75 M (28.71 ft) SW of the centerline of
Worchester st, 5.51 m (18.08 ft) WNW of the NE corner of a white knee wall at
the entrance of the base, 2.50 m (8.20 ft) WNW of the NE corner of a fence, the
bench mark is set at ground level, crimped to the top of a stainless steel rod
driven an unspecified depth, and encased in a 4-inch PVC pipe and concrete kick
block.
BENCH MARK STAMPING: 11-11 RESET 2000 BALTIMORE
DESIGNATION: 857 0283 11-11 RESET
MONUMENTATION: Survey disk VM#: 16830
AGENCY: US Army Corps of Engineers (USE) IDB PID#: DL8735
SETTING CLASSIFICATION: Bulkhead OPUS PID:
LATITUDE: 38° 19.7' N ( 38.32819) LONGITUDE: 75° 5.5' W ( -75.09097)
The bench mark is a disk set in the bulkhead cap along the boat basin, 9.65 m
(31.66 ft) SW of the NW corner of the dock shack, 8.68 M (28.48 ft) NW of a
metal light pole, 0.85 m (2.79 ft) east of the NW corner of the dock, and set
flush in the concrete dock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 7
Station ID: 8570283 PUBLICATION DATE: 04/28/2020
Name: OCEAN CITY INLET
MD
NOAA Chart: 12211 Latitude: 38° 19.7' N ( 38.32833)
USGS Quad: OCEAN CITY Longitude: 75° 5.5' W ( -75.09167)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: SPEICHER 1956
DESIGNATION: SPEICHER
MONUMENTATION: Survey disk VM#: 16832
AGENCY: US Army Corps of Engineers (USE) IDB PID#: HU0266
SETTING CLASSIFICATION: Sea wall OPUS PID#: HU0266
LATITUDE: 38° 19.5' N ( 38.32514) LONGITUDE: 75° 5.3' W ( -75.08814)
The bench mark is a disk set in the sea wall on the north side of the inlet
located near the intersection of Boardwalk Street and Baltimore Street, 14.72 m
(48.3 ft) SSW of the centerline of Baltimore Street, 7.53 m (24.7 ft) ESE of the
west corner of a metal handrail, and 0.42 m (1.4 ft) north of the south edge of
the sea wall.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 7
Station ID: 8570283 PUBLICATION DATE: 04/28/2020
Name: OCEAN CITY INLET
MD
NOAA Chart: 12211 Latitude: 38° 19.7' N ( 38.32833)
USGS Quad: OCEAN CITY Longitude: 75° 5.5' W ( -75.09167)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 6 1931
DESIGNATION: TIDAL 6 STA 1
MONUMENTATION: Tidal Station disk VM#: 17700
AGENCY: US Coast and Geodetic Survey
(USC&GS) IDB PID#: HU0267
SETTING CLASSIFICATION: Brick chimmey OPUS PID:
LATITUDE: 38° 19.8' N ( 38.32917) LONGITUDE: 75° 5.2' W ( -75.08708)
The bench mark is a disk set flush in the concrete foundation of the brick
chimney at the NW corner of the Hotel Atlantic, near the intersection of
Baltimore Avenue and Somerset Street, 35.69 m (117.1 ft) east of the east curb
of Baltimore Avenue, 6.40 m (21.0 ft) south of the south curb of Somerset
Street, 0.24 m (0.79 ft) north of the north edge, 0.20 m (0.66 ft) west of the
west edge, and 0.25 m (0.8 ft) above the level of the ground.
BENCH MARK STAMPING: INLET BALTO DIST 1994
DESIGNATION: 857 0283 11/11 INLET
MONUMENTATION: Survey disk VM#: 18664
AGENCY: US Corp of Engineers (USE) IDB PID:
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 38° 19.7' N ( 38.32797) LONGITUDE: 75° 5.5' W ( -75.09092)
The bench mark is set flush in a concrete monument, 25.78 m (84.6 ft) west of
the north leg of a three legged tower, 17.84 m (58.5 ft) south of a metal light
pole, 4.36 m (14.3 ft) SSW of the SW corner of a metal building, and 0.3 m (1.0
ft) above the ground.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 7
Station ID: 8570283 PUBLICATION DATE: 04/28/2020
Name: OCEAN CITY INLET
MD
NOAA Chart: 12211 Latitude: 38° 19.7' N ( 38.32833)
USGS Quad: OCEAN CITY Longitude: 75° 5.5' W ( -75.09167)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: F 104 RESET
DESIGNATION: F 104 RESET
MONUMENTATION: Tidal Station disk VM#: 19241
AGENCY: National Ocean Survey/Service (NOS) IDB PID#: DL8738
SETTING CLASSIFICATION: Concrete drive way OPUS PID:
LATITUDE: 38° 19.8' N ( 38.33003) LONGITUDE: 75° 5.2' W ( -75.08742)
The mark is 29.25 m (96.0 ft) north of the centerline of Dorchester Street, 7.08
m (23.2 ft) northwest of the center of the fire hydrant at the southwest corner
of the intersection of Baltimore Avenue and Dorchester Street, and 6.25 m (20.5
ft) southeast of the southwest corner of the fire company building.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 7
Station ID: 8570283 PUBLICATION DATE: 04/28/2020
Name: OCEAN CITY INLET
MD
NOAA Chart: 12211 Latitude: 38° 19.7' N ( 38.32833)
USGS Quad: OCEAN CITY Longitude: 75° 5.5' W ( -75.09167)
T I D A L D A T U M S
Tidal datums at OCEAN CITY INLET based on:
LENGTH OF SERIES: 12 YEARS
TIME PERIOD: 8/2002-7/2008, 4/2009-3/2015
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8557380 LEWES, FT. MILES
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
HIGHEST OBSERVED WATER LEVEL (02/05/1998) = 1.845
MEAN HIGHER HIGH WATER MHHW = 0.749
MEAN HIGH WATER MHW = 0.687
North American Vertical Datum NAVD88 = 0.528
MEAN SEA LEVEL MSL = 0.387
MEAN TIDE LEVEL MTL = 0.367
MEAN LOW WATER MLW = 0.047
MEAN LOWER LOW WATER MLLW = 0.000
LOWEST OBSERVED WATER LEVEL (01/06/2018) = -0.760
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
0280 J 1982 2.523 1.836
0280 H 1980 2.059 1.372
11-11 RESET 2000 BALTIMORE 2.279 1.592
SPEICHER 1956 3.477 2.790
6 1931 2.674 1.987
INLET BALTO DIST 1994 2.017 1.330
F 104 RESET 1.560 0.873
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 7 of 7
Station ID: 8570283 PUBLICATION DATE: 04/28/2020
Name: OCEAN CITY INLET
MD
NOAA Chart: 12211 Latitude: 38° 19.7' N ( 38.32833)
USGS Quad: OCEAN CITY Longitude: 75° 5.5' W ( -75.09167)
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.