NOAA Web Site Link Tides and Currents Home Page Transparent placeholder image

Bench Mark Sheet for 8573704, Betterton MD

Superseded Epoch

Large map location marker Station Location
Small red map location marker Published bench mark
Small blue map location marker Unpublished bench mark

Bench mark positions only appear on the map if their coordinates in the CO-OPS database are at the precision of degrees/minutes/seconds/and tenths of seconds. If the coordinates are less precise, the mark will not appear.

Printable version

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  6

                                                                                
Station ID: 8573704                         PUBLICATION DATE:  04/21/2003
Name:       BETTERTON, SASSAFRAS RIVER                        
            MD
NOAA Chart: 12274                           Latitude:   39° 22.3' N (  39.37170)
USGS Quad:  BETTERTON                       Longitude:  76°  3.8' W ( -76.06330)


To reach the tidal bench marks from the intersection of Route 291 and Route 213
in Chesterton, travel 6.2 km (3.7 mi) north on Route 213 to Route 561, turn left
and proceed 3.9 km (2.4 mi) to Route 298 in Lynch, turn left and proceed 1.6
miles (2.6 km) to Route 292, turn left and proceed to a T junction, turn left
again staying on Route 292 to its end.  The bench marks are located along Route
292. The tide gage and staff were located on the Kent County Public Pier.


                         T I D A L   B E N C H   M A R K S
                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  6

                                                                                
Station ID: 8573704                         PUBLICATION DATE:  04/21/2003
Name:       BETTERTON, SASSAFRAS RIVER                        
            MD
NOAA Chart: 12274                           Latitude:   39° 22.3' N (  39.37170)
USGS Quad:  BETTERTON                       Longitude:  76°  3.8' W ( -76.06330)


                         T I D A L   B E N C H   M A R K S


                 PRIMARY BENCH MARK STAMPING:  NO 4 1938
                         DESIGNATION:          TIDAL 4 STA 59

MONUMENTATION:           Tidal Station disk                    VM#:         3162
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  JV0549
SETTING CLASSIFICATION:  Concrete step support                 OPUS PID:        
LATITUDE:   39° 22.2' N (  39.37000)          LONGITUDE:  76°  3.7' W ( -76.06170)


The primary bench mark is a disk set vertically in the north face of a concrete
support for the concrete steps leading uphill to the entrance on the north side
of Rigbie Hotel, 33 m (108 ft) east of the NE corner of the post office, 10.67 m
(35.0 ft) east of the centerline of Main Street, 3.20 m (10.5 ft) south of the
extended centerline of Ericsson Avenue, and 0.43 m (1.4 ft) above ground.



                         BENCH MARK STAMPING:  NO 6 1971
                         DESIGNATION:          857 3704 TIDAL 6

MONUMENTATION:           Tidal Station disk                    VM#:         3163
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete pad                          OPUS PID:        
LATITUDE:   39° 22.2' N (  39.37000)          LONGITUDE:  76°  3.7' W ( -76.06170)


The bench mark is a disk set in a cement pad on the side of the pumphouse,
located on the west side of a pump house at the east end of a parking lot east
of Main Street at the foot of a hill, 11.58 m (38.0 ft) NE of a power pole at
the SE corner of the lot,10.67 m (35.0 ft) east of the east end of the parking
lot pavement, 1.98 m (6.5 ft) SW of the NW corner of the pump house, and 0.46 m
(1.5 ft) ENE of a witness post.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  6

                                                                                
Station ID: 8573704                         PUBLICATION DATE:  04/21/2003
Name:       BETTERTON, SASSAFRAS RIVER                        
            MD
NOAA Chart: 12274                           Latitude:   39° 22.3' N (  39.37170)
USGS Quad:  BETTERTON                       Longitude:  76°  3.8' W ( -76.06330)


                         T I D A L   B E N C H   M A R K S


                         BENCH MARK STAMPING:  NO 7 1971
                         DESIGNATION:          857 3704 TIDAL 7

MONUMENTATION:           Tidal Station disk                    VM#:         3164
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:        
SETTING CLASSIFICATION:  Retaining wall                        OPUS PID:        
LATITUDE:   39° 22.2' N (  39.37000)          LONGITUDE:  76°  3.7' W ( -76.06170)


The bench mark is a disk set flush in the top of the south end of a retaining
wall on the west side of Main Street, 37.73 m (123.8 ft) south of the north end
of the retaining wall, 16.37 m (53.7 ft) south of the south retaining wall for
steps in the main retaining wall, 10.03 m (32.9 ft) NW of power pole 33999
29830, 4.48 m (14.7 ft) west of the centerline of Main Street, and 0.46 m (1.5
ft) north of the south end of the retaining wall.



                         BENCH MARK STAMPING:  3704 A 1999
                         DESIGNATION:          857 3704 A

MONUMENTATION:           Tidal Station disk                    VM#:        15889
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Flagpole foundation                   OPUS PID#: BBBM87
LATITUDE:   39° 22.2' N (  39.37000)          LONGITUDE:  76°  3.7' W ( -76.06170)


The bench mark is a disk set in a foundation for three flag poles, just south of
the south side of Ericson Avenue, 17.98 m (59.0 ft) west of a fire hydrant,
11.81 m (38.8 ft) south of the centerline of Ericson Avenue, 5.15 m (16.9 ft)
east of the west end of the concrete foundation, and 0.12 m (0.4 ft) above
ground level.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  6

                                                                                
Station ID: 8573704                         PUBLICATION DATE:  04/21/2003
Name:       BETTERTON, SASSAFRAS RIVER                        
            MD
NOAA Chart: 12274                           Latitude:   39° 22.3' N (  39.37170)
USGS Quad:  BETTERTON                       Longitude:  76°  3.8' W ( -76.06330)


                         T I D A L   B E N C H   M A R K S


                         BENCH MARK STAMPING:  3704 B 1999
                         DESIGNATION:          857 3704 B

MONUMENTATION:           Tidal Station disk                    VM#:        15890
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Picnic shelter slab                   OPUS PID:        
LATITUDE:   39° 22.2' N (  39.37000)          LONGITUDE:  76°  3.7' W ( -76.06170)


The bench mark is a disk set in the concrete slab foundation for the picnic
shelter on a hill overlooking the beach at Betterton, 16.43 m (53.9 ft) west of
a light pole, 12.07 m (39.6 ft) east of the western edge of the foundation, 5.03
m (16.5 ft) north of the south edge of the foundation, and 3.15 m (10.3 ft)
south of the north edge of the foundation.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  6

                                                                                
Station ID: 8573704                         PUBLICATION DATE:  04/21/2003
Name:       BETTERTON, SASSAFRAS RIVER                        
            MD
NOAA Chart: 12274                           Latitude:   39° 22.3' N (  39.37170)
USGS Quad:  BETTERTON                       Longitude:  76°  3.8' W ( -76.06330)


                            T I D A L   D A T U M S 


Tidal datums at BETTERTON, SASSAFRAS RIVER based on:

     LENGTH OF SERIES:      7 Months
     TIME PERIOD:           June 1999 - December 1999
     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   =  0.657
     MEAN HIGH WATER                            MHW    =  0.554
     MEAN SEA LEVEL                             MSL    =  0.315
     MEAN TIDE LEVEL                            MTL    =  0.310
     MEAN LOW WATER                             MLW    =  0.066
     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 4 1938                                   5.267    4.713
     NO 6 1971                                   2.164    1.610
     NO 7 1971                                  11.568   11.014
     3704 A 1999                                 3.840    3.286
     3704 B 1999                                12.622   12.068


                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of  6

                                                                                
Station ID: 8573704                         PUBLICATION DATE:  04/21/2003
Name:       BETTERTON, SASSAFRAS RIVER                        
            MD
NOAA Chart: 12274                           Latitude:   39° 22.3' N (  39.37170)
USGS Quad:  BETTERTON                       Longitude:  76°  3.8' W ( -76.06330)


                             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.

Return to Top
Products available at 8573704 Betterton, MD

Revised: 08/08/2018
NOAA / National Ocean Service
Web site owner: Center for Operational Oceanographic Products and Services