U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  5

                                                                                
Station ID: 8517137                         PUBLICATION DATE:  01/13/2016
Name:       BEACH CHANNEL CROSS B. BRIDGE                     
            NY
NOAA Chart: 12350                           Latitude:   40° 35.3' N (  40.58830)
USGS Quad:  FAR ROCKAWAY                    Longitude:  73° 49.2' W ( -73.82000)


To reach the station from JFK airport in Queens, NY, follow Belt Parkway 4.7 km
(2.9 mi) west to exit 17S for Cross Bay Boulevard, proceed south on Cross Bay
Boulevard 8.8 km (5.5 mi) through the toll plaza and to the end of the Cross Bay
Bridge, stay left to take the exit for Far Rockaway and continue to stay left
0.4 km (0.25 mi) south and then west around the exit ramp to merge onto Beach
Channel Drive, immediately turn left and proceed north on Beach 92nd Street 0.05
km (0.03 mi) to Thai Rock Restaurant and the tide station in the outside eating
area.  The bench marks are along the seawall west of the restaurant.


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


                 PRIMARY BENCH MARK STAMPING:  7137 B 2015
                         DESIGNATION:          851 7137 B

MONUMENTATION:           DB                                    VM#:        21383
AGENCY:                  National Ocean Service                IDB PID#:        
SETTING CLASSIFICATION:  Abutments and piers of large bridges  OPUS PID:        
LATITUDE:   40° 35.3' N (  40.58822)          LONGITUDE:  73° 49.1' W ( -73.81853)


The primary bench mark is a disk set in the NW corner of the bridge abutment,
14.06 m (46.1 ft) SW of pathway light pole p6, 13.34 m (43.8 ft) W of street
light pole c84 for bridge traffic, 11.46 m (37.6 ft) E of NW fence corner under
bridge, 8.67 m (28.4 ft) SE of pathway light pole p7, 1.65 m (5.4 ft) N of NE
fence corner under bridge and about 1.4 m (4.6 ft) higher than the ground.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  5

                                                                                
Station ID: 8517137                         PUBLICATION DATE:  01/13/2016
Name:       BEACH CHANNEL CROSS B. BRIDGE                     
            NY
NOAA Chart: 12350                           Latitude:   40° 35.3' N (  40.58830)
USGS Quad:  FAR ROCKAWAY                    Longitude:  73° 49.2' W ( -73.82000)


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


                         BENCH MARK STAMPING:  7137 A 2015
                         DESIGNATION:          851 7137 A

MONUMENTATION:           DB                                    VM#:        21384
AGENCY:                  National Ocean Service                IDB PID#:        
SETTING CLASSIFICATION:  Retaining walls                       OPUS PID:        
LATITUDE:   40° 35.3' N (  40.58875)          LONGITUDE:  73° 49.0' W ( -73.81725)


The bench mark is a disk set in the top of E end of the N wall for the
pedestrian path up to the bridge, 17.66 m (57.9 ft) SW of power pole near
Mcdonalds restaurant drive thru, 17.09 m (56.1 ft) SE of E most pathway light
pole in park S of seawall, 16.68 m (54.7 ft) S of fire hydrant on W side of dead
end Beach 92nd street, 15.79 m (51.8 ft) NNE of E facing sign for cross bay Vet
Mem Bridge Belt Parkway, 9.37 m (30.7 ft) NW of stop sign at NW corner of Beach
92nd street and Beach Channel drive intersection and about 0.76 m (2.5 ft)
higher than the ground.



                         BENCH MARK STAMPING:  7137 C 2015
                         DESIGNATION:          851 7137 C

MONUMENTATION:           DB                                    VM#:        21385
AGENCY:                  National Ocean Service                IDB PID#:        
SETTING CLASSIFICATION:  Massive retaining walls               OPUS PID:        
LATITUDE:   40° 35.3' N (  40.58769)          LONGITUDE:  73° 49.2' W ( -73.81969)


The bench mark is a disk set in the top of the concrete seawall, 25.16 m (82.5
ft) NE of light pole p16, 18.79 m (61.6 ft) N of NW end of a fence at bridge
abutment, 10.35 m (34.0 ft) NNE of light pole p15, 9.50 m (31.2 ft) W of first
pathway light pole p14 W of bridge off ramp and 6.32 m (20.7 ft) WSW of sign on
seawall railing for discharge outfall point rk-011.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  5

                                                                                
Station ID: 8517137                         PUBLICATION DATE:  01/13/2016
Name:       BEACH CHANNEL CROSS B. BRIDGE                     
            NY
NOAA Chart: 12350                           Latitude:   40° 35.3' N (  40.58830)
USGS Quad:  FAR ROCKAWAY                    Longitude:  73° 49.2' W ( -73.82000)


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


                         BENCH MARK STAMPING:  7137 D 2015
                         DESIGNATION:          851 7137 D

MONUMENTATION:           DB                                    VM#:        21386
AGENCY:                  National Ocean Service                IDB PID#:        
SETTING CLASSIFICATION:  Massive retaining walls               OPUS PID#: BBDV24
LATITUDE:   40° 35.2' N (  40.58722)          LONGITUDE:  73° 49.2' W ( -73.82061)


The bench mark is a disk set in the top of the concrete seawall, 27.83 m (91.3
ft) WSW of sign on seawall railing warning of outfall during dry weather, 17.37
m (57.0 ft) W of light pole p19, 15.12 m (49.6 ft) NE of light pole p21 and 5.83
m (19.1 ft) N of light pole p20.



                         BENCH MARK STAMPING:  7137 E 2015
                         DESIGNATION:          851 7137 E

MONUMENTATION:           DB                                    VM#:        21387
AGENCY:                  National Ocean Service                IDB PID#:        
SETTING CLASSIFICATION:  Retaining walls                       OPUS PID:        
LATITUDE:   40° 35.2' N (  40.58681)          LONGITUDE:  73° 49.3' W ( -73.82147)


The bench mark is a disk set in the top of the SE end of the concrete wall
inland of the riprap shore around beach channel high school, 24.39 m (80.0 ft)
NW of light pole on N side of Beach Channel drive near end of W bound bridge
exit lane, 18.22 m (59.8 ft) NNW of the SE corner of school fence at sidewalk
along Beach Channel drive, 10.83 m (35.5 ft) W of police your pets sign, 0.45 m
(1.5 ft) S of W end of stainless steel seawall railing and about 0.6 m (2.0 ft)
higher than the ground.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  5

                                                                                
Station ID: 8517137                         PUBLICATION DATE:  01/13/2016
Name:       BEACH CHANNEL CROSS B. BRIDGE                     
            NY
NOAA Chart: 12350                           Latitude:   40° 35.3' N (  40.58830)
USGS Quad:  FAR ROCKAWAY                    Longitude:  73° 49.2' W ( -73.82000)


                            T I D A L   D A T U M S 


Tidal datums at BEACH CHANNEL CROSS B. BRIDGE based on:

     LENGTH OF SERIES:      5 MONTHS
     TIME PERIOD:           April 2015 - August 2015
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8531680 SANDY HOOK


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

     MEAN HIGHER HIGH WATER                     MHHW   =  1.831
     MEAN HIGH WATER                            MHW    =  1.723
     MEAN TIDE LEVEL                            MTL    =  0.894
     MEAN SEA LEVEL                             MSL    =  0.892
     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

     7137 B 2015                                 4.602    2.879
     7137 A 2015                                 4.095    2.372
     7137 C 2015                                 3.310    1.587
     7137 D 2015                                 3.321    1.598
     7137 E 2015                                 3.944    2.221


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

                                                                                
Station ID: 8517137                         PUBLICATION DATE:  01/13/2016
Name:       BEACH CHANNEL CROSS B. BRIDGE                     
            NY
NOAA Chart: 12350                           Latitude:   40° 35.3' N (  40.58830)
USGS Quad:  FAR ROCKAWAY                    Longitude:  73° 49.2' W ( -73.82000)


                             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.