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Bench Mark Sheet for 8638863, Chesapeake Bay Bridge Tunnel VA

Superseded Epoch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Small blue map location marker Unpublished bench mark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: 8638863                         PUBLICATION DATE:  10/06/2011
Name:       CHESAPEAKE BAY BRIDGE TUNNEL                      
            VA
NOAA Chart: 12254                           Latitude:   36° 58.0' N (  36.96667)
USGS Quad:  CAPE HENRY                      Longitude:  76°  6.8' W ( -76.11333)


To reach the tidal bench marks from the toll booth on the south end of
Chesapeake Bay Bridge Tunnel (CBBT) in Virginia Beach, proceed north on U.S.
Highway 13 for 4.8 km (3.0 mi) to the south entrance of the Thimble Shoal
Tunnel. The bench marks are located on the fishing pier and the around the
tunnel entrance. The tide station is located in a steel room below the deck of
the fishing pier and 90 m (295 ft) west of the inshore end of the pier.


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


                 PRIMARY BENCH MARK STAMPING:  NO. 2 1975
                         DESIGNATION:          863 8863 TIDAL 2

MONUMENTATION:           Tidal Station disk                    VM#:         1555
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AJ4591
SETTING CLASSIFICATION:  Concrete pier deck                    OPUS PID:        
LATITUDE:   36° 58.0' N (  36.96631)          LONGITUDE:  76°  6.8' W ( -76.11294)


The primary bench mark is a disk set on top of the reataining wall on the west
side of th island, at the entrance to the fishing pier, 22.10 m (72.5 ft) WSW
and across the drive/parking lot from the SW corner of the brick tunnel air
exchange building, 3.38 m (11.1 ft) west of the SW end of a bridge description
sign, and 2.47 m (8.1 ft) NNE of the NE corner of a restaurant.

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

                                                                                
Station ID: 8638863                         PUBLICATION DATE:  10/06/2011
Name:       CHESAPEAKE BAY BRIDGE TUNNEL                      
            VA
NOAA Chart: 12254                           Latitude:   36° 58.0' N (  36.96667)
USGS Quad:  CAPE HENRY                      Longitude:  76°  6.8' W ( -76.11333)


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


                         BENCH MARK STAMPING:  NO. 1 1975
                         DESIGNATION:          863 8863 TIDAL 1

MONUMENTATION:           Tidal Station disk                    VM#:         1554
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete pier deck                    OPUS PID:        
LATITUDE:   36° 58.1' N (  36.96753)          LONGITUDE:  76°  6.9' W ( -76.11456)


The bench mark is a disk set in the concrete pier deck at the NE inside corner
of the T end of the fishing pier, 7.99 m (26.2 feet) east of the west end of the
pier, 5.67 m (18.6 feet) north of the south face of the pier, and 0.98 m (3.2
feet) SSW of the north face of the pier.



                         BENCH MARK STAMPING:  NO. 3 1975
                         DESIGNATION:          863 8863 TIDAL 3

MONUMENTATION:           Tidal Station disk                    VM#:         1556
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete bulkhead                     OPUS PID#: BBBY81
LATITUDE:   36° 58.0' N (  36.96672)          LONGITUDE:  76°  6.7' W ( -76.11244)


The bench mark is a disk set in the concrete bulkhead at the rip-rap north of
the tunnel air exchange building, 13.90 m (45.6 ft) north of the north face of
the air exchange building, 7.01 m (23.0 ft) ENE of the center of a 0.70 m (2.3
ft) diameter manhole cover, 4.63 m (15.2 ft) west of the green navigation light,
0.61 m (2.0 ft) south of the north edge of the bulkhead, and 0.3 m (1 ft) west
of the Paul De Grasse dedication monument.

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

                                                                                
Station ID: 8638863                         PUBLICATION DATE:  10/06/2011
Name:       CHESAPEAKE BAY BRIDGE TUNNEL                      
            VA
NOAA Chart: 12254                           Latitude:   36° 58.0' N (  36.96667)
USGS Quad:  CAPE HENRY                      Longitude:  76°  6.8' W ( -76.11333)


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


                         BENCH MARK STAMPING:  13
                         DESIGNATION:          863 8863 TIDAL 13

MONUMENTATION:           Bolt                                  VM#:         1557
AGENCY:                                                        IDB PID#:        
SETTING CLASSIFICATION:  Concrete bulkhead                     OPUS PID:        
LATITUDE:   36° 58.0' N (  36.96644)          LONGITUDE:  76°  6.8' W ( -76.11286)


The bench mark is a brass bolt set in top of the concrete bulkhead at the
rip-rap on the NW side of the tunnel entrance, 28.96 m (95.0 ft) SW of the NW
corner of the air exchange building, 23.47 m (77.0 ft) north of the north side
of the fishing pier entrance, 22.86 m (75.0 ft) east of the west face of the air
exchange building, and 0.43 m (1.4 ft) east of the west face of the bulkhead.

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

                                                                                
Station ID: 8638863                         PUBLICATION DATE:  10/06/2011
Name:       CHESAPEAKE BAY BRIDGE TUNNEL                      
            VA
NOAA Chart: 12254                           Latitude:   36° 58.0' N (  36.96667)
USGS Quad:  CAPE HENRY                      Longitude:  76°  6.8' W ( -76.11333)


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


                         BENCH MARK STAMPING:  19
                         DESIGNATION:          863 8863 DE GRASSE
                         ALIAS:                DE GRASSE

MONUMENTATION:           Bolt                                  VM#:         6491
AGENCY:                                                        IDB PID#:        
SETTING CLASSIFICATION:  Concrete bulkhead                     OPUS PID:        
LATITUDE:   36° 58.0' N (  36.96664)          LONGITUDE:  76°  6.7' W ( -76.11244)


The bench mark is a brass bolt set in the concrete bulkhead at the rip-rap north
of the tunnel air exchange building, 13.99 m (45.9 ft) NE of the NE face of the
air exchange building, 8.60 m (28.2 ft) NW of the NW side of the Paul De Grasse
dedication monument, and 0.49 m (1.6 ft) SW of the SE face of the island.



                         BENCH MARK STAMPING:  8863 A 1993
                         DESIGNATION:          863 8863 A

MONUMENTATION:           Tidal Station disk                    VM#:         6492
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete bulkhead                     OPUS PID#: BBCB25
LATITUDE:   36° 58.0' N (  36.96614)          LONGITUDE:  76°  6.7' W ( -76.11225)


The bench mark is a disk set in the concrete bulkhead at the rip-rap on the east
side of the tunnel entrance, 35.48 m (116.4 ft) SE of the NE corner of the air
exchange building, 25.69 m (84.3 ft) ENE of the SE corner of the air exchange
building, and 0.61 m (2.0 ft) west of the east face of the concrete bulkhead.

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

                                                                                
Station ID: 8638863                         PUBLICATION DATE:  10/06/2011
Name:       CHESAPEAKE BAY BRIDGE TUNNEL                      
            VA
NOAA Chart: 12254                           Latitude:   36° 58.0' N (  36.96667)
USGS Quad:  CAPE HENRY                      Longitude:  76°  6.8' W ( -76.11333)


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


                         BENCH MARK STAMPING:  8863 B 1993
                         DESIGNATION:          863 8863 B

MONUMENTATION:           Tidal Station disk                    VM#:         6493
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Tunnel entrance wall foundation       OPUS PID:        
LATITUDE:   36° 54.8' N (  36.91333)          LONGITUDE:  76°  6.8' W ( -76.11375)


The bench mark is a disk set in the foundation at the south end of the east
tunnel entrance wall, 46.18 m (151.5 ft) NNE of the concrete control box on the
east side of the highway, 14.20 m (46.6 ft) WNW of the east face of the
retaining wall, 7.96 m (26.1 ft) SE of the centerline of the highway, and 0.15 m
(0.5 ft) south of the north face of the wall.



                         BENCH MARK STAMPING:  8863 C 2000
                         DESIGNATION:          863 8863 C

MONUMENTATION:           Tidal Station disk                    VM#:        16424
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete bulkhead of tunnel           OPUS PID:        
LATITUDE:   36° 57.9' N (  36.96558)          LONGITUDE:  76°  6.8' W ( -76.11319)


The bench mark is a disk set in a concrete bulkhead on the west side of Thimble
Shoals Island, 29.00 m (95.1 ft) SW of the SE corner of the seagull restaurant,
25.12 m (82.4 ft) west of the west face of the retaining wall of the tunnel, and
0.50 m (1.6 ft) east of the western face of the concrete bulkhead.

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

                                                                                
Station ID: 8638863                         PUBLICATION DATE:  10/06/2011
Name:       CHESAPEAKE BAY BRIDGE TUNNEL                      
            VA
NOAA Chart: 12254                           Latitude:   36° 58.0' N (  36.96667)
USGS Quad:  CAPE HENRY                      Longitude:  76°  6.8' W ( -76.11333)


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


                         BENCH MARK STAMPING:  8863 D 2008
                         DESIGNATION:          863 8863 D

MONUMENTATION:           Tidal Station disk                    VM#:        19130
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete seawall                      OPUS PID:        
LATITUDE:   36° 57.8' N (  36.96411)          LONGITUDE:  76°  6.8' W ( -76.11383)


The benchmark is set in a massive concrete retaining seawall located on the
north corner of the newest section of seawall at the SW side of the island,
15.30 m (50.20 ft) NW of centerline of road leading to pier and restaurant, 6.70
m (21.98 ft) NW of 90 degree junction of old and new seawall, 0.65 m (2.13 ft)
SE of NW face of corner, and 0.50 m (1.64 ft) SW of the NE face of corner wall.



                         BENCH MARK STAMPING:  8863 E 2008
                         DESIGNATION:          863 8863 E

MONUMENTATION:           Tidal Station disk                    VM#:        19131
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete seawall                      OPUS PID:        
LATITUDE:   36° 57.8' N (  36.96325)          LONGITUDE:  76°  6.8' W ( -76.11414)


The benchmark is  set in a massive concrete seawall, located on the SW corner of
the newest section of seawall on the SW side of the island, 13.30 m (43.64 ft)
SE of the NW bridge abutement in the vicinity of the bridge span, 7.30m (23.95
ft) NW of a 90 degree junction of the old and new seawalls, 0.80m (2.62 ft) NE
of the SW face of the seawall corner, and 0.60m (1.97 ft) SE of the NW face of
wall corner.    

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

                                                                                
Station ID: 8638863                         PUBLICATION DATE:  10/06/2011
Name:       CHESAPEAKE BAY BRIDGE TUNNEL                      
            VA
NOAA Chart: 12254                           Latitude:   36° 58.0' N (  36.96667)
USGS Quad:  CAPE HENRY                      Longitude:  76°  6.8' W ( -76.11333)


                            T I D A L   D A T U M S 


Tidal datums at CHESAPEAKE BAY BRIDGE TUNNEL based on:

     LENGTH OF SERIES:      19 YEARS
     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 (11/12/2009)         =  2.304
     MEAN HIGHER HIGH WATER                     MHHW   =  0.884
     MEAN HIGH WATER                            MHW    =  0.814
     MEAN SEA LEVEL                             MSL    =  0.431
     MEAN TIDE LEVEL                            MTL    =  0.426
     MEAN LOW WATER                             MLW    =  0.037
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (01/11/1978)         = -0.895

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     NO. 2 1975                                  8.210    7.396
     NO. 1 1975                                  7.578    6.764
     NO. 3 1975                                  8.217    7.402
     13                                          8.199    7.385
     19                                          8.237    7.422
     8863 A 1993                                 8.135    7.320
     8863 B 1993                                 8.067    7.252
     8863 C 2000                                 8.171    7.357
     8863 D 2008                                 7.930    7.116
     8863 E 2008                                 7.900    7.086


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

                                                                                
Station ID: 8638863                         PUBLICATION DATE:  10/06/2011
Name:       CHESAPEAKE BAY BRIDGE TUNNEL                      
            VA
NOAA Chart: 12254                           Latitude:   36° 58.0' N (  36.96667)
USGS Quad:  CAPE HENRY                      Longitude:  76°  6.8' W ( -76.11333)


                             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.

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Products available at 8638863 Chesapeake Bay Bridge Tunnel, VA

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