U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  9

                                                                                
Station ID: 8577330                         PUBLICATION DATE:  10/06/2011
Name:       SOLOMONS ISLAND, PATUXENT RIVER                   
            MD
NOAA Chart: 12284                           Latitude:   38° 19.0' N (  38.31667)
USGS Quad:  SOLOMONS ISLAND                 Longitude:  76° 27.1' W ( -76.45167)


To reach the tidal bench marks from State Highway 214 in Calvert County, proceed
south towards Solomons, bear left at the highway split, continue south on
Highway 2 and 4 for 2.3 km (1.4 mi) to the Chesapeake Biological Laboratory Pier
on the left and the Pump House at the end of the pier.  The bench marks are
within 1.6 km (1 mi) radius of the tide gage.  The tide gage and staff are
located on the pier.  Station is inside the Pump House - the key must be
obtained from the front office.


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


                 PRIMARY BENCH MARK STAMPING:  7330 E 1980
                         DESIGNATION:          857 7330 E TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:          455
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AJ8036
SETTING CLASSIFICATION:  Galvanized steel rod                  OPUS PID#: AJ8036
LATITUDE:   38° 19.2' N (  38.31951)          LONGITUDE:  76° 27.2' W ( -76.45318)


The primary bench mark is a disk located near the entrance to Solomons Marina,
10.67 m (35.0 ft) SE of the centerline of the entrance to the Marina, 6.43 m
(21.1 ft) NNE of the centerline of Charles Street, 2.16 m (7.1 ft) south of the
southernmost post of the Solomons Marina sign, and 1.01 m (3.3 ft) NW of the
chain link fence around the boat storage yard.  The bench mark is 0.03 m (0.1
ft) below ground, crimped to a galvanized steel rod driven 12.2 m (40 ft) to
refusal, and encased in a 5-inch PVC pipe and concrete kickblock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  9

                                                                                
Station ID: 8577330                         PUBLICATION DATE:  10/06/2011
Name:       SOLOMONS ISLAND, PATUXENT RIVER                   
            MD
NOAA Chart: 12284                           Latitude:   38° 19.0' N (  38.31667)
USGS Quad:  SOLOMONS ISLAND                 Longitude:  76° 27.1' W ( -76.45167)


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


                         BENCH MARK STAMPING:  NO 5 1937
                         DESIGNATION:          TIDAL 5 STA 89

MONUMENTATION:           Tidal Station disk                    VM#:          449
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  HV0367
SETTING CLASSIFICATION:  Concrete wall                         OPUS PID:        
LATITUDE:   38° 19.1' N (  38.31839)          LONGITUDE:  76° 27.2' W ( -76.45375)


The bench mark is a disk set in the top of the NE end of the 3.05 m (10 ft) long
concrete wall, located on the NW side of the steps leading to the basement of
the Chesapeake Biological Laboratory building, 23.87 m (78.3 ft) south of bench
mark NO 11 1963, 9.36 m (30.7 ft) SW of the north corner of the building, 2.07 m
(6.8 ft) NE of the NE edge of the steps, and 0.9 m (3 ft) NW of the NW wall of
the building.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  9

                                                                                
Station ID: 8577330                         PUBLICATION DATE:  10/06/2011
Name:       SOLOMONS ISLAND, PATUXENT RIVER                   
            MD
NOAA Chart: 12284                           Latitude:   38° 19.0' N (  38.31667)
USGS Quad:  SOLOMONS ISLAND                 Longitude:  76° 27.1' W ( -76.45167)


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


                         BENCH MARK STAMPING:  10 1946
                         DESIGNATION:          TIDAL 10 STA 89

MONUMENTATION:           Tidal Station disk                    VM#:          450
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  HV0371
SETTING CLASSIFICATION:  Concrete step                         OPUS PID:        
LATITUDE:   38° 19.1' N (  38.31858)          LONGITUDE:  76° 27.2' W ( -76.45403)


The bench mark is a disk set in the SE end of the second step from the bottom of
the NE entrance to Nice Hall, 11.70 m (38.4 ft) WNW of the west corner of the
Biological Research Laboratory, 6.71 m (22.0 ft) ESE of the NW corner of Nice
Hall, 4.69 m (15.4 ft) north of the east corner of Nice Hall, 2.80 m (9.2 ft) NE
of the NE side of Nice Hall, and 0.18 m (0.6 ft) above ground.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  9

                                                                                
Station ID: 8577330                         PUBLICATION DATE:  10/06/2011
Name:       SOLOMONS ISLAND, PATUXENT RIVER                   
            MD
NOAA Chart: 12284                           Latitude:   38° 19.0' N (  38.31667)
USGS Quad:  SOLOMONS ISLAND                 Longitude:  76° 27.1' W ( -76.45167)


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


                         BENCH MARK STAMPING:  NO 11 1963
                         DESIGNATION:          TIDAL 11 STA 89

MONUMENTATION:           Tidal Station disk                    VM#:          451
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  HV0369
SETTING CLASSIFICATION:  Concrete step                         OPUS PID:        
LATITUDE:   38° 19.1' N (  38.31856)          LONGITUDE:  76° 27.2' W ( -76.45381)


The bench mark is a disk set in the east corner of the top concrete step,
located at the SW entrance to the two story brick Biological Research Laboratory
building, 13.81 m (45.3 ft) SE of the west corner of the building, 10.73 m (35.2
ft) NW of the SE corner of the building, 1.76 m (5.8 ft) ESE of the SW edge of
the steps, and 0.21 m (0.7 ft) above the level of the ground.



                         BENCH MARK STAMPING:  7330 C 1979
                         DESIGNATION:          857 7330 C

MONUMENTATION:           Tidal Station disk                    VM#:          453
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete wall                         OPUS PID:        
LATITUDE:   38° 19.2' N (  38.31964)          LONGITUDE:  76° 27.3' W ( -76.45528)


The bench mark is a disk set on top of the concrete wall at the east side of the
steps located at the west entrance to the Harbor Island Marina Inc., 28.35 m
(93.0 ft) SSE of the bulkhead at the Marina, 9.91 m (32.5 ft) north of the
entrance to the Harbor Island Gift Shop, 4.82 m (15.8 ft) south of the
centerline of Charles Street, and 0.43 m (1.4 ft) above ground.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  9

                                                                                
Station ID: 8577330                         PUBLICATION DATE:  10/06/2011
Name:       SOLOMONS ISLAND, PATUXENT RIVER                   
            MD
NOAA Chart: 12284                           Latitude:   38° 19.0' N (  38.31667)
USGS Quad:  SOLOMONS ISLAND                 Longitude:  76° 27.1' W ( -76.45167)


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


                         BENCH MARK STAMPING:  7330 D 1980
                         DESIGNATION:          857 7330 D

MONUMENTATION:           Tidal Station disk                    VM#:          454
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Galvanized steel rod                  OPUS PID:        
LATITUDE:   38° 19.2' N (  38.31975)          LONGITUDE:  76° 27.1' W ( -76.45228)


The bench mark is a disk located at the intersection of Charles Street and
Patuxent Avenue, 47.98 m (157.4 ft) NNE of power pole No. 44, 9.36 m (30.7 ft)
east of the centerline of Patuxent Avenue, 3.32 m (10.9 ft) SE of power pole No.
45, 1.19 m (3.9 ft) west of the bulkhead, and 0.61 m (2.0 ft) east of the
galvanized guard rail.  The bench mark is 0.24 m (0.8 ft) below ground, crimped
to a galvanized steel rod driven 9.14 m (30.0 ft) to refusal, and encased in a
5-inch PVC pipe with concrete kickblock.



                         BENCH MARK STAMPING:  7330 F 1998
                         DESIGNATION:          857 7330 F TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:        15481
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Retaining wall                        OPUS PID#: AJ8037
LATITUDE:   38° 19.2' N (  38.31964)          LONGITUDE:  76° 26.4' W ( -76.43928)


The bench mark is a disk set in a concrete retaining wall located on the north
side of Charles Street near a brick county pump station, 8.70 m (28.5 ft) NW of
the centerline of Charles Street, 5.62 m (18.4 ft) SSE of the wooden bulkhead on
the north side of Charles Street, 2.00 m (6.6 ft) WSW of the west wall of the
pump house, and 0.76 m (2.5 ft) above ground.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of  9

                                                                                
Station ID: 8577330                         PUBLICATION DATE:  10/06/2011
Name:       SOLOMONS ISLAND, PATUXENT RIVER                   
            MD
NOAA Chart: 12284                           Latitude:   38° 19.0' N (  38.31667)
USGS Quad:  SOLOMONS ISLAND                 Longitude:  76° 27.1' W ( -76.45167)


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


                         BENCH MARK STAMPING:  7330 G 2003
                         DESIGNATION:          857 7330 G

MONUMENTATION:           Tidal Station disk                    VM#:        16990
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Loading dock                          OPUS PID:        
LATITUDE:   38° 19.2' N (  38.31950)          LONGITUDE:  76° 27.3' W ( -76.45428)


The bench mark is a disk set in a loading dock near the intersection of Charles
Street and Patuxent Avenue, 22.92 m (75.2 ft) SW of the centerline of Charles
Street, 9.06 m (29.7 ft) NE of the SE corner of the loading dock, 2.87 m (9.4
ft) NW of the NE wall of the loading dock, 0.25 m (0.8 ft) SE of the NW face of
the loading dock, and 0.60 m (2.0 ft) above the asphalt parking area.



                         BENCH MARK STAMPING:  7330 H 2006
                         DESIGNATION:          857 7330 H

MONUMENTATION:           Metal Rod                             VM#:        18177
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod in sleeve         OPUS PID:        
LATITUDE:   38° 18.2' N (  38.30416)          LONGITUDE:  76° 27.1' W ( -76.45197)


The bench mark is a steel rod located 35.55 m (116.6 ft) NNE of a fire hydrant,
20.36 m (66.8 ft) NE of the NE corner of the University of MD Center for
Environmental Sciences Research Fleet Operations building, 2.05 m (6.7 ft) SSW
of the edge of the parking lot, and 1.80 m (5.9 ft) WNW of a witness post. The
datum point is the top of a  steel rod driven 17.7 m (58 ft) to refusal, and
encased in a 5-inch PVC pipe concrete kickblock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  7 of  9

                                                                                
Station ID: 8577330                         PUBLICATION DATE:  10/06/2011
Name:       SOLOMONS ISLAND, PATUXENT RIVER                   
            MD
NOAA Chart: 12284                           Latitude:   38° 19.0' N (  38.31667)
USGS Quad:  SOLOMONS ISLAND                 Longitude:  76° 27.1' W ( -76.45167)


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


                         BENCH MARK STAMPING:  7330 J 2006
                         DESIGNATION:          857 7330 J

MONUMENTATION:           Metal Rod                             VM#:        18178
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod in sleeve         OPUS PID:        
LATITUDE:   38° 19.1' N (  38.31792)          LONGITUDE:  76° 27.3' W ( -76.45528)


The bench mark is a steel rod located at the University of MD building and
maintenance facility at the western end of the parking lot, 35.76 m (117.3 ft)
WNW of the southern post of the gate at the main entrance, 9.02 m (29.6 ft) SW
of the west corner of the wooden garage, 7.20 m (23.6 ft) NE of the SW fence
corner of the gravel parking lot.  The datum point is a metal rod driven 7.3 m
(24 ft) to refusal, and encased in a 5-inch PVC pipe and concrete kickblock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  8 of  9

                                                                                
Station ID: 8577330                         PUBLICATION DATE:  10/06/2011
Name:       SOLOMONS ISLAND, PATUXENT RIVER                   
            MD
NOAA Chart: 12284                           Latitude:   38° 19.0' N (  38.31667)
USGS Quad:  SOLOMONS ISLAND                 Longitude:  76° 27.1' W ( -76.45167)


                            T I D A L   D A T U M S 


Tidal datums at SOLOMONS ISLAND, PATUXENT RIVER 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 (09/01/2006)         =  1.343
     MEAN HIGHER HIGH WATER                     MHHW   =  0.449
     MEAN HIGH WATER                            MHW    =  0.404
     North American Vertical Datum              NAVD88 =  0.259
     MEAN SEA LEVEL                             MSL    =  0.230
     MEAN TIDE LEVEL                            MTL    =  0.226
     MEAN LOW WATER                             MLW    =  0.048
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (01/01/1963)         = -1.135

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     7330 E 1980                                 3.321    2.916
     NO 5 1937                                   4.508    4.104
     10 1946                                     4.363    3.959
     NO 11 1963                                  4.642    4.238
     7330 C 1979                                 2.324    1.920
     7330 D 1980                                 2.282    1.878
     7330 F 1998                                 1.731    1.327
     7330 G 2003                                 4.838    4.433
     7330 H 2006                                 1.143    0.738
     7330 J 2006                                 0.956    0.551


                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  9 of  9

                                                                                
Station ID: 8577330                         PUBLICATION DATE:  10/06/2011
Name:       SOLOMONS ISLAND, PATUXENT RIVER                   
            MD
NOAA Chart: 12284                           Latitude:   38° 19.0' N (  38.31667)
USGS Quad:  SOLOMONS ISLAND                 Longitude:  76° 27.1' W ( -76.45167)


                             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.