U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
PUBLICATION DATE: 12/17/1985
Station ID: 8571266 SUPERCEDED DATE: 04/21/2003
Name: RUMBLEY, GOOSE CREEK, MANOKIN RIVER
MARYLAND
NOAA Chart: 12231 Latitude: 38° 5.5' N
USGS Quad: MARION Longitude: 75° 51.7' W
To reach the tidal bench marks from Salisbury, Maryland, take U.S. Route 13 for
20 miles (32 km) south to Maryland Route 413, then proceed 2 miles (3 km) south
on Route 413 to Westover, Maryland and its intersection with Maryland State
Route 361, then 6.2 miles (10.0 km) west on State Route 361 through Upper
Fairmont, Maryland, to where State Route 361 changes from a secondary highway to
a light duty road named Fairmont Rumbley Road, proceed 1.6 miles (2.6 km) to
where the road makes a 90 right turn, then 2.2 miles (3.5 km) to the end of the
road and the traffic circle in Rumbley, Maryland. The bench marks are located
in the vicinity of the traffic circle. The tide gage and staff were located on
the County Pier to the south of the traffic circle.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 1266 A 1981
MONUMENTATION: Survey Disk VM#: 3049
AGENCY: PID:
SETTING CLASSIFICATION: Stainless Steel Rod
The bench mark is 70.8 feet (21.6 m) east of the southeasternmost corner of the
southwesternmost building at the traffic circle in Rumbley, 49.7 feet (15.1 m)
ESE of the south corner of the building in the middle of a traffic circle, 28.3
feet (8.6 m) west of the northwesternmost corner of the County Pier, and 12.0
feet (3.7 m) north of the south edge of the bulkhead. The bench mark is crimped
to the top of a stainless steel rod driven 72 feet (22 m) to refusal.
BENCH MARK STAMPING: 1266 B 1981
MONUMENTATION: Survey Disk VM#: 3050
AGENCY: PID:
SETTING CLASSIFICATION: Stainless Steel Rod
The bench mark is north of the NW end of the road at Rumbley, 142 feet (43 m) SW
of telephone pole number 201C on the north side of the road where it turns into
a circle, 125 feet (38 m) NNE of the north corner of the building in the middle
of the traffic circle, 110 feet (34 m) NNE of the NE corner of the center of
three buildings on the west side of a circle, and 15.0 feet (4.6 m) NE of
telephone pole number 201D. The bench mark is crimped to the top of a stainless
steel rod driven 33 feet (10 m) to refusal.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
PUBLICATION DATE: 12/17/1985
Station ID: 8571266 SUPERCEDED DATE: 04/21/2003
Name: RUMBLEY, GOOSE CREEK, MANOKIN RIVER
MARYLAND
NOAA Chart: 12231 Latitude: 38° 5.5' N
USGS Quad: MARION Longitude: 75° 51.7' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 1266 C 1981
MONUMENTATION: Survey Disk VM#: 3051
AGENCY: PID:
SETTING CLASSIFICATION: Stainless Steel Rod
The bench mark is 161 feet (49 m) NE of Bench Mark 1266 B 1981, 123 feet (37 m)
SW of telephone pole number 201F in front of the westernmost house on the north
side of the road before the circle, 50.8 feet (15.5 m) SW of the SW corner of
the shack SW of the house, 32 feet (10 m) NNW of the centerline of the road
leading to the circle and 18.6 feet (5.7 m) NE of telephone pole number 201C.
The bench mark is crimped to the top of a stainless steel rod driven 72 feet (22
m) to refusal.
BENCH MARK STAMPING: 1266 D 1981
MONUMENTATION: Survey Disk VM#: 3052
AGENCY: PID:
SETTING CLASSIFICATION: Stainless Steel Rod
The bench mark is in the southeasternmost corner of the front yard of the
westernmost house on the north side of the road before the circle, 193 feet (59
m) NE of Bench Mark 1266 C 1981, 83.4 feet (25.4 m) east of the SW corner of the
house, 76.6 feet (23.3 m) west of the west end of the bulkhead which runs along
the road, 69.4 feet (21.2 m) NE of telephone pole number 201F, 55.4 feet (16.9
m) SE of the SE corner of the house, and 15 feet (5 m) north of the centerline
of the road. The bench mark is crimped to the top of a stainless steel rod
driven 72 feet (22 m) to refusal.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
PUBLICATION DATE: 12/17/1985
Station ID: 8571266 SUPERCEDED DATE: 04/21/2003
Name: RUMBLEY, GOOSE CREEK, MANOKIN RIVER
MARYLAND
NOAA Chart: 12231 Latitude: 38° 5.5' N
USGS Quad: MARION Longitude: 75° 51.7' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 1266 E 1981
MONUMENTATION: Survey Disk VM#: 3053
AGENCY: PID:
SETTING CLASSIFICATION: Stainless Steel Rod
The bench mark is 225 feet (69 m) NE of Bench Mark 1266 D 1981, 172 feet (52 m)
NE of the west end of the bulkhead along the road, 107 feet (33 m) ESE of the
middle front porch step in front of the westernmost two-story house on the north
side of the road leading to the circle, 43 feet (13 m) NNW of the centerline of
the road leading to the circle, and 17 feet (5 m) NE of the centerline of the
last north to south road before the circle. The bench mark is crimped to the
top of a stainless steel rod driven 72 feet (22 m) to refusal.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
PUBLICATION DATE: 12/17/1985
Station ID: 8571266 SUPERCEDED DATE: 04/21/2003
Name: RUMBLEY, GOOSE CREEK, MANOKIN RIVER
MARYLAND
NOAA Chart: 12231 Latitude: 38° 5.5' N
USGS Quad: MARION Longitude: 75° 51.7' W
T I D A L D A T U M S
Tidal datums at RUMBLEY, GOOSE CREEK, MANOKIN RIVER based on:
LENGTH OF SERIES: 1 MONTH
TIME PERIOD: NOVEMBER 1981
TIDAL EPOCH: 1960-1978
CONTROL TIDE STATION: 8638610 HAMPTON ROADS, VA
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in FEET:
HIGHEST OBSERVED WATER LEVEL (11/16/1981) = 4.04
MEAN HIGHER HIGH WATER MHHW = 2.16
MEAN HIGH WATER MHW = 2.06
MEAN TIDE LEVEL MTL = 1.10
MEAN LOW WATER MLW = 0.14
MEAN LOWER LOW WATER MLLW = 0.00
LOWEST OBSERVED WATER LEVEL (11/08/1981) = -0.50
Bench Mark Elevation Information In FEET above:
Stamping or Designation MLLW MHW
1266 A 1981 0.91 -1.15
1266 B 1981 0.82 -1.24
1266 C 1981 1.72 -0.34
1266 D 1981 1.25 -0.81
1266 E 1981 2.09 0.03
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
PUBLICATION DATE: 12/17/1985
Station ID: 8571266 SUPERCEDED DATE: 04/21/2003
Name: RUMBLEY, GOOSE CREEK, MANOKIN RIVER
MARYLAND
NOAA Chart: 12231 Latitude: 38° 5.5' N
USGS Quad: MARION Longitude: 75° 51.7' 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.