U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  7

                                                                                
Station ID: 8575512                         PUBLICATION DATE:  10/14/2011
Name:       U.S. NAVAL ACADEMY, SEVERN R., CHES. BAY          
            MD
NOAA Chart: 12282                           Latitude:   38° 59.0' N (  38.98328)
USGS Quad:  ANNAPOLIS                       Longitude:  76° 28.9' W ( -76.48156)


To reach the tidal bench marks from gate number 8 of the U.S. Naval Academy,
proceed SE on Bowyer Road over a bridge to McNair Road, continue NE on McNair
Road to Santee Road, proceed on Santee Road for 0.5 km (0.3 mi) to Santee Basin.
 The bench marks are located within the U.S. Naval Academys grounds. The gage
and staff are located on Santee Pier in the Oceanography Laboratory Building.


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


                 PRIMARY BENCH MARK STAMPING:  7
                         DESIGNATION:          857 5512 TIDAL 7

MONUMENTATION:           Tidal Station disk                    VM#:          438
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  HV0207
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   38° 59.0' N (  38.98325)          LONGITUDE:  76° 28.9' W ( -76.48167)


The primary bench mark is a disk set in a concrete monument located near the
northern corner of Luce Hall, 5.55 m (18.2 ft) SW of the edge of the sidewalk on
the south side of Santee Road, 4.45 m (14.6 ft) NE of the NE edge of the
sidewalk entrance to Luce Hall, 3.23 m (10.6 ft) NW of the ironwood (locust
tree), 2.86 m (9.4 ft) SE of the SE corner of the concrete foundation for an
oriental monument, and 0.15 m (0.5 ft) below ground.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  7

                                                                                
Station ID: 8575512                         PUBLICATION DATE:  10/14/2011
Name:       U.S. NAVAL ACADEMY, SEVERN R., CHES. BAY          
            MD
NOAA Chart: 12282                           Latitude:   38° 59.0' N (  38.98328)
USGS Quad:  ANNAPOLIS                       Longitude:  76° 28.9' W ( -76.48156)


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


                         BENCH MARK STAMPING:  2 1928
                         DESIGNATION:          TIDAL 2 STA 80

MONUMENTATION:           Tidal Station disk                    VM#:          441
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  HV0206
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   38° 58.9' N (  38.98214)          LONGITUDE:  76° 29.1' W ( -76.48481)


The bench mark is a disk set in a concrete monument along the north edge of
Chambers Walk between Chauvenet Walk and Chapel Walk, 62 m (203 ft) SE of the
centerline of Chapel Walk, 41 m (136 ft) SW of the centerline of Stribling Walk,
27.04 m (88.7 ft) east of a granite monument for the Judge Joseph Hopper
Nicholson Memorial bronze plaque, 23 m (75 ft) NE of the NE lamp post, 21.06 m
(69.1 ft) NW of the NW edge of Chauvenet Walk, 0.09 m (0.30 ft) NE of the NE
edge of Chambers Walk, and 0.03 m (0.10 ft) below ground.  

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  7

                                                                                
Station ID: 8575512                         PUBLICATION DATE:  10/14/2011
Name:       U.S. NAVAL ACADEMY, SEVERN R., CHES. BAY          
            MD
NOAA Chart: 12282                           Latitude:   38° 59.0' N (  38.98328)
USGS Quad:  ANNAPOLIS                       Longitude:  76° 28.9' W ( -76.48156)


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


                         BENCH MARK STAMPING:  3 1928
                         DESIGNATION:          TIDAL 3 STA 80

MONUMENTATION:           Tidal Station disk                    VM#:          442
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  HV0205
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   38° 59.0' N (  38.98286)          LONGITUDE:  76° 29.2' W ( -76.48592)


The bench mark is a disk set in a concrete monument at the NE edge of Chambers
Walk in an area bounded by Stribling Walk, Chauvenet Walk, Chapel Walk, and
Maryland Avenue, 54 m (176 ft) south of the south corner of the Mecedonian
monument, 18.11 m (59.4 ft) west of the center of a manhole cover, 17.87 m (58.6
ft) NNW of the NW face of a 3.55 m (11.6 ft) circumference tulip poplar tree,
0.22 m (0.7 ft) west of the edge of Chambers Walk, and 0.06 m (0.2 ft) below
ground.



                         BENCH MARK STAMPING:  5 1928
                         DESIGNATION:          857 5512 TIDAL 5

MONUMENTATION:           Tidal Station disk                    VM#:          443
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  HV0204
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   38° 58.9' N (  38.98247)          LONGITUDE:  76° 29.2' W ( -76.48631)


The bench mark is a disk set in a concrete monument in an area bounded by
Chauvenet Walk, Blake Road, Maryland Avenue and Chapel Walk, 42.55 m (139.6 ft)
WNW of the west corner of the granite foundation for a monument which bears the
letters HERNDON, 42 m (138 ft) SE of the SE curb of Maryland Avenue, 30.94 m
(101.5 ft) SW of the SW edge of Chauvenet Walk, 19.96 m (65.5 ft) NE of the NE
curb of Blake Road, and 13 m (44 ft) south of the south edge of an east-west
brick walk.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  7

                                                                                
Station ID: 8575512                         PUBLICATION DATE:  10/14/2011
Name:       U.S. NAVAL ACADEMY, SEVERN R., CHES. BAY          
            MD
NOAA Chart: 12282                           Latitude:   38° 59.0' N (  38.98328)
USGS Quad:  ANNAPOLIS                       Longitude:  76° 28.9' W ( -76.48156)


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


                         BENCH MARK STAMPING:  5510 A 1978
                         DESIGNATION:          857 5512 A

MONUMENTATION:           Tidal Station disk                    VM#:          444
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   38° 59.0' N (  38.98256)          LONGITUDE:  76° 28.8' W ( -76.48064)


The bench mark is a disk located at the SE face of Luce Hall, 6.16 m (20.2 ft)
SW of the east corner of Luce Hall, 4.36 m (14.3 ft) NE of the centerline of the
SE entrance to Luce Hall, and 0.52 m (1.7 ft) SE of the SE wall of Luce Hall.
The bench mark is 0.03 m (0.1 ft) below ground, crimped to a stainless steel rod
driven 13 m (42 ft) to refusal, and encased in a 4-inch PVC pipe with concrete
kickblock.



                         BENCH MARK STAMPING:  5510 B 1978
                         DESIGNATION:          857 5512 B TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         1409
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AC6864
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   38° 59.0' N (  38.98319)          LONGITUDE:  76° 28.9' W ( -76.48156)


The bench mark is a disk located at the NW face of Luce Hall, 6.92 m (22.7 ft)
NE of the centerline of the NW entrance to Luce Hall, 3.57 m (11.7 ft) SW of the
north corner of Luce Hall, and 0.43 m (1.4 ft) NW of the NW wall of Luce Hall.
The bench mark is 3 cm (0.1 ft) below ground, crimped to a stainless steel rod
driven 11.0 m (36 ft) to refusal, and encased in a 4-inch PVC pipe with concrete
kickblock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  7

                                                                                
Station ID: 8575512                         PUBLICATION DATE:  10/14/2011
Name:       U.S. NAVAL ACADEMY, SEVERN R., CHES. BAY          
            MD
NOAA Chart: 12282                           Latitude:   38° 59.0' N (  38.98328)
USGS Quad:  ANNAPOLIS                       Longitude:  76° 28.9' W ( -76.48156)


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


                         BENCH MARK STAMPING:  5510 D 1979 RESET
                         DESIGNATION:          857 5512 D TIDAL RESET

MONUMENTATION:           Tidal Station disk                    VM#:        16271
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AJ8035
SETTING CLASSIFICATION:  Concrete bulkhead                     OPUS PID#: BBDJ75
LATITUDE:   38° 59.0' N (  38.98328)          LONGITUDE:  76° 28.7' W ( -76.47911)


The bench mark is a disk set in the concrete bulkhead located at the east corner
of Santee Pier near the Hendrix Oceanographic Lab, 13.65 m (44.8 ft) SE of the
SE face of the foundation for a steel crane, 11.45 m (37.6 ft) NE of the NE face
of a small wooden shed, and 0.15 m (0.5 ft) SW of the NE face of the bulkhead.



                         BENCH MARK STAMPING:  5512 E 2006
                         DESIGNATION:          857 5512 E

MONUMENTATION:           Tidal Station disk                    VM#:        18169
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete bulkhead                     OPUS PID:        
LATITUDE:   38° 59.0' N (  38.98400)          LONGITUDE:  76° 28.8' W ( -76.48006)


The bench mark is a disk set in the concrete bulkhead located at the north
corner of the Santee Pier near the Hendrix Oceanographic Lab,  60.30 m (197.8
ft) NE of the NE corner of the foundation of the field mantainance building, 
21.31 m (69.9 ft) E of the NE corner of the foundation of a green high voltage
box (TS-74) next to the practice field, and 19.27 m (63.2 ft) NNW of the NW
corner of the foundation of the cutter shed.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of  7

                                                                                
Station ID: 8575512                         PUBLICATION DATE:  10/14/2011
Name:       U.S. NAVAL ACADEMY, SEVERN R., CHES. BAY          
            MD
NOAA Chart: 12282                           Latitude:   38° 59.0' N (  38.98328)
USGS Quad:  ANNAPOLIS                       Longitude:  76° 28.9' W ( -76.48156)


                            T I D A L   D A T U M S 


Tidal datums at U.S. NAVAL ACADEMY, SEVERN R., CHES. BAY 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 (09/19/2003)         =  2.183
     MEAN HIGHER HIGH WATER                     MHHW   =  0.438
     MEAN HIGH WATER                            MHW    =  0.364
     North American Vertical Datum              NAVD88 =  0.235
     MEAN SEA LEVEL                             MSL    =  0.219
     MEAN TIDE LEVEL                            MTL    =  0.215
     MEAN LOW WATER                             MLW    =  0.067
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (12/31/1962)         = -1.194

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     7                                           1.500    1.136
     2 1928                                      6.119    5.755
     3 1928                                      5.028    4.664
     5 1928                                      6.716    6.352
     5510 A 1978                                 1.690    1.326
     5510 B 1978                                 1.723    1.359
     5510 D 1979 RESET                           1.641    1.277
     5512 E 2006                                 1.980    1.616


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

                                                                                
Station ID: 8575512                         PUBLICATION DATE:  10/14/2011
Name:       U.S. NAVAL ACADEMY, SEVERN R., CHES. BAY          
            MD
NOAA Chart: 12282                           Latitude:   38° 59.0' N (  38.98328)
USGS Quad:  ANNAPOLIS                       Longitude:  76° 28.9' W ( -76.48156)


                             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.