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Bench Mark Sheet for 8594900, Washington DC

Superseded Epoch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Small blue map location marker Unpublished bench mark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  8

                                                                                
Station ID: 8594900                                PUBLICATION DATE:  09/05/2003
Name:       WASHINGTON, POTOMAC RIVER                         
            DC
NOAA Chart: 12289                                  Latitude:         38° 52.4' N
USGS Quad:  WASHINGTON WEST                        Longitude:        77°  1.3' W


To reach the tidal bench marks from where I-395 northbound splits, travel 1.0 km
(0.7 mi) along I-395 northbound to the Maine Avenue S.W. exit.  Take the Maine
Avenue SW exit road for 0.3 km (0.2 mi) until it dead ends into Water Street
S.W.  Turn SE onto Water Street, S.W. and proceed to the end of Water Street to
the Police and Fire Harbor Patrol Office at Pier 5.  The bench marks are located
along Water Street, Maine Avenue, and Pier 5, and the tide station is in a
separate room located halfway along the north side of the Police building.


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


                 PRIMARY BENCH MARK STAMPING:  TIDAL NO 1 1951
                         DESIGNATION:          859 4900 TIDAL 1

MONUMENTATION:           Tidal Station disk                        VM#:      456
AGENCY:                  CGS                                       PID#:  HV1980
SETTING CLASSIFICATION:  Concrete sea wall


The primary bench mark is a disk set in the concrete seawall at the southern
inshore corner of Pier 4, 13.90 m (45.6 ft) SW of the centerline of Water
Street, S.W., 5.49 m (18.0 ft) SE of the center of the south gate leading to the
pier, 3.57 m (11.7 ft) east of the east corner of the Washington Boat Lines
building, and 1.77 m (5.8 ft) SE of the first brick fence pillar SE of the
building.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  8

                                                                                
Station ID: 8594900                                PUBLICATION DATE:  09/05/2003
Name:       WASHINGTON, POTOMAC RIVER                         
            DC
NOAA Chart: 12289                                  Latitude:         38° 52.4' N
USGS Quad:  WASHINGTON WEST                        Longitude:        77°  1.3' W


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


                         BENCH MARK STAMPING:  NO 4 1973
                         DESIGNATION:          859 4900 TIDAL 4

MONUMENTATION:           Tidal Station disk                        VM#:      458
AGENCY:                  National Ocean Survey (NOS)               PID#:  HV9068
SETTING CLASSIFICATION:  Concrete sea wall


The bench mark is a disk set in the concrete seawall just north of Pier 4, 25.45
m (83.5 ft) NW of the center of the NW gate to the pier, 18.0 m (59 ft) south of
the southern corner of a concrete curb surrounding a paid parking area, 13.59 m
(44.6 ft) SW of the centerline of water street, and 3.69 m (12.1 ft) NW  of the
NW corner of the third brick pillar NW of the gate.



                         BENCH MARK STAMPING:  NO 5 1973
                         DESIGNATION:          859 4900 TIDAL 5

MONUMENTATION:           Tidal Station disk                        VM#:      459
AGENCY:                  National Ocean Survey (NOS)               PID#:  HV9069
SETTING CLASSIFICATION:  Concrete sea wall


The bench mark is a disk set in the concrete seawall at the northern inshore
corner of Pier 4, 25.0 m (82 ft) SW of the first light pole NW of the Washington
Boat Lines driveway entrance, 13.90 m (45.6 ft) SW of the centerline of Water
Street, 3.63 m (11.9 ft) NW of the center of the NW gate entrance, 2.90 m (9.5
ft) north of the NW corner of the Washington Boat Lines building, and 0.40 m
(1.3 ft) NW of the first brick fence pillar NW of the NW gate.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  8

                                                                                
Station ID: 8594900                                PUBLICATION DATE:  09/05/2003
Name:       WASHINGTON, POTOMAC RIVER                         
            DC
NOAA Chart: 12289                                  Latitude:         38° 52.4' N
USGS Quad:  WASHINGTON WEST                        Longitude:        77°  1.3' W


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


                         BENCH MARK STAMPING:  4900 A 1977
                         DESIGNATION:          859 4900 A

MONUMENTATION:           Tidal Station disk                        VM#:      461
AGENCY:                  National Ocean Survey (NOS)               PID:         
SETTING CLASSIFICATION:  Concrete ramp


The bench mark is a disk set in a concrete delivery ramp located at the NW
corner of the south half of the Arena Stage Theater building, 30.5 m (100 ft)
east of the start of the sidewalk leading to the ramp from the sidewalk along
the NE side of Maine Avenue, 4 m (13 ft) west of the double steel doors of the
ramp, and 0.30 m (1.0 ft) north of the south wall of the ramp.



                         BENCH MARK STAMPING:  4900 B 1977
                         DESIGNATION:          859 4900 B

MONUMENTATION:           Tidal Station disk                        VM#:      462
AGENCY:                  National Ocean Survey (NOS)               PID:         
SETTING CLASSIFICATION:  Ventilation shaft


The bench mark is a disk set in the concrete retaining wall of a ventilation
shaft  located on the north wall near the NE corner of the north half of the
Arena Stage Theater building, 12.83 m (42.1 ft) west of the west curb of 6th
Street, 2.50 m (8.2 ft) south of the south curb of the Arena Stage northern
parking lot, and 1.16 m (3.8 ft) north of the north wall of the building.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  8

                                                                                
Station ID: 8594900                                PUBLICATION DATE:  09/05/2003
Name:       WASHINGTON, POTOMAC RIVER                         
            DC
NOAA Chart: 12289                                  Latitude:         38° 52.4' N
USGS Quad:  WASHINGTON WEST                        Longitude:        77°  1.3' W


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


                         BENCH MARK STAMPING:  4900 C 1977
                         DESIGNATION:          859 4900 C

MONUMENTATION:           Tidal Station disk                        VM#:      463
AGENCY:                  National Ocean Survey (NOS)               PID:         
SETTING CLASSIFICATION:  Concrete retaining wall


The bench mark is a disk set in the NW corner of a concrete retaining wall
bordering the entrance to an underground parking lot just south of the building
at 700 Water Street, 20.85 m (68.4 ft) SSE of the south wall of the building,
18.59 m (61.0 ft) north of a bell in the park area SE of the parking lot
entrance, 5.82 m (19.1 ft) north of the SW corner of the retaining wall, and
1.37 m (4.5 ft) above the parking lot.



                         BENCH MARK STAMPING:  4900 E 1982
                         DESIGNATION:          859 4900 E

MONUMENTATION:           Tidal Station disk                        VM#:      465
AGENCY:                  National Ocean Survey (NOS)               PID:         
SETTING CLASSIFICATION:  Galvanized steel rod


The bench mark is a disk located along the east side of Water Street near its
intersection with 6th Street, S.W., 20.55 m (67.4 ft) NNW of the centerline of
6th Street, 15.39 m (50.5 ft) north of the light pole at the NE corner of 6th
Street and Water Street, 7.35 m (24.1 ft) east of the centerline of Water
Street, and 3.87 m (12.7 ft) NNE of the center of the manhole cover just east of
the east curb of Water Street. The bench mark is crimped to a galvanized steel
rod driven 4.3 m (14 ft) to refusal, and encased in a 4-inch PVC pipe with cap.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  8

                                                                                
Station ID: 8594900                                PUBLICATION DATE:  09/05/2003
Name:       WASHINGTON, POTOMAC RIVER                         
            DC
NOAA Chart: 12289                                  Latitude:         38° 52.4' N
USGS Quad:  WASHINGTON WEST                        Longitude:        77°  1.3' W


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


                         BENCH MARK STAMPING:  4900 F 1982
                         DESIGNATION:          859 4900 F

MONUMENTATION:           Tidal Station disk                        VM#:      466
AGENCY:                  National Ocean Survey (NOS)               PID:         
SETTING CLASSIFICATION:  Galvanized steel rod


The bench mark is a disk set along the NE side of Water Street near its
intersection with Connector Road, S.W., 20.85 m (68.4 ft) WSW of the first light
pole north of the Maine Avenue and Connector Road intersection, 5.00 m (16.4 ft)
NW of the center of the manhole cover just NW of the NW corner of Connector Road
and Water Street, and 1.01 m (3.3 ft) NE of the NE curb of Water Street.  The
bench mark is crimped to a galvanized steel rod driven 9.1 m (30 ft) to refusal,
and encased in a 4-inch PVC pipe with cap.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of  8

                                                                                
Station ID: 8594900                                PUBLICATION DATE:  09/05/2003
Name:       WASHINGTON, POTOMAC RIVER                         
            DC
NOAA Chart: 12289                                  Latitude:         38° 52.4' N
USGS Quad:  WASHINGTON WEST                        Longitude:        77°  1.3' W


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


                         BENCH MARK STAMPING:   
                         DESIGNATION:          RV PIER 4

MONUMENTATION:           Rivet                                     VM#:      467
AGENCY:                  US Coast and Geodetic Survey (USC&GS)     PID#:  HV1983
SETTING CLASSIFICATION:  Concrete pier deck


The bench mark is a monel rivet set near the SW corner of the Spirit of
Washington Cruises loading dock at Pier 4, 2.80 m (9.2 ft) NNE of a bumper post
with a light, 0.52 m (1.7 ft) north of the most easterly of 9 bumper posts at
the SW end of the pier, and 0.20 m (0.7 ft) NW of the SE edge of the pier.  



                         BENCH MARK STAMPING:  4900 H 1989
                         DESIGNATION:          859 4900 H

MONUMENTATION:           Tidal Station disk                        VM#:      468
AGENCY:                  National Ocean Service (NOS)              PID:         
SETTING CLASSIFICATION:  Concrete pier deck


The bench mark is a disk set in the concrete deck along the NW side of the DC
Police and Fire Harbor Patrol pier (Pier 5), 8.14 m (26.71 ft) SE of the NW edge
of the pier, 3.72 m (12.20 ft) NW of the door to the tide station room, and 0.24
m (0.79 ft) south of the SW corner of the protruding entrance to the boat repair
bay.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  7 of  8

                                                                                
Station ID: 8594900                                PUBLICATION DATE:  09/05/2003
Name:       WASHINGTON, POTOMAC RIVER                         
            DC
NOAA Chart: 12289                                  Latitude:         38° 52.4' N
USGS Quad:  WASHINGTON WEST                        Longitude:        77°  1.3' W


                            T I D A L   D A T U M S 


Tidal datums at WASHINGTON, POTOMAC RIVER based on:

     LENGTH OF SERIES:      228 MONTHS
     TIME PERIOD:           January 1983 - December 2001
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:   


Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:

     HIGHEST OBSERVED WATER LEVEL (10/17/1942)         =  3.368
     MEAN HIGHER HIGH WATER                     MHHW   =  0.965
     MEAN HIGH WATER                            MHW    =  0.896
     MEAN SEA LEVEL                             MSL    =  0.472
     MEAN TIDE LEVEL                            MTL    =  0.471
     North American Vertical Datum              NAVD88 =  0.425
     MEAN LOW WATER                             MLW    =  0.047
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (02/26/1967)         = -1.539

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     TIDAL NO 1 1951                             2.728    1.831
     NO 4 1973                                   2.853    1.957
     NO 5 1973                                   2.733    1.837
     4900 A 1977                                 5.739    4.843
     4900 B 1977                                 6.534    5.638
     4900 C 1977                                 6.070    5.174
     4900 E 1982                                 4.581    3.685
     4900 F 1982                                 4.157    3.261
     RV PIER 4                                   2.750    1.854
     4900 H 1989                                 2.766    1.870


                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  8 of  8

                                                                                
Station ID: 8594900                                PUBLICATION DATE:  09/05/2003
Name:       WASHINGTON, POTOMAC RIVER                         
            DC
NOAA Chart: 12289                                  Latitude:         38° 52.4' N
USGS Quad:  WASHINGTON WEST                        Longitude:        77°  1.3' 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.

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Products available at 8594900 Washington, DC

Revised: 10/15/2013
NOAA / National Ocean Service
Web site owner: Center for Operational Oceanographic Products and Services