U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  6

                                                                                
Station ID: 9752235                         PUBLICATION DATE:  06/03/2020
Name:       CULEBRA                                           
            PR
NOAA Chart: 25653                           Latitude:   18° 18.1' N (  18.30086)
USGS Quad:  CULEBRA AND ADJACENT ISLANDS    Longitude:  65° 18.1' W ( -65.30247)


On the island of Culebra, Puerto Rico, in the town of Dewey, at the Culebra
ferry terminal, station is located on the waters edge, being a white aluminum
enclosure mounted on aluminum stand.


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


                 PRIMARY BENCH MARK STAMPING:  2235 D 2005
                         DESIGNATION:          975 2235 D

MONUMENTATION:           Tidal Station disk                    VM#:        17958
AGENCY:                  National Ocean Service (NOS)          IDB PID#:  DN8624
SETTING CLASSIFICATION:  Concrete bulkhead                     OPUS PID#: DN8624
LATITUDE:   18° 18.1' N (  18.30114)          LONGITUDE:  65° 18.1' W ( -65.30250)


The primary bench mark is a NOS disk set flush in the concrete bulkhead located
7.57 m (24.8 ft) ESE of the south end of the bottom step of six steps leading to
the water, 3.90 m (12.8 ft) south of the north face of a 1.1 m (3.6 ft) high
block wall, 3.05 m (10.0 ft) west of the east face of the terminal building.



                         BENCH MARK STAMPING:  2235 B 2005
                         DESIGNATION:          975 2235 B

MONUMENTATION:           Tidal Station disk                    VM#:        17956
AGENCY:                  National Ocean Service (NOS)          IDB PID#:  DN8622
SETTING CLASSIFICATION:  Concrete bulkhead                     OPUS PID:        
LATITUDE:   18° 18.1' N (  18.30108)          LONGITUDE:  65° 18.1' W ( -65.30222)


The bench mark is a disk set flush in the concrete bulkhead located 18.10 m
(59.4 ft) SW of the SW corner of Culebra divers store, 9.92 m (32.6 ft) SE of
the NE corner of the ticket office of the ferry terminal, 3.70 m (12.1 ft) west
of two gas hoses, and 0.3 m (1.0 ft) below the street level.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  6

                                                                                
Station ID: 9752235                         PUBLICATION DATE:  06/03/2020
Name:       CULEBRA                                           
            PR
NOAA Chart: 25653                           Latitude:   18° 18.1' N (  18.30086)
USGS Quad:  CULEBRA AND ADJACENT ISLANDS    Longitude:  65° 18.1' W ( -65.30247)


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


                         BENCH MARK STAMPING:  2235 C 2005
                         DESIGNATION:          975 2235 C

MONUMENTATION:           Tidal Station disk                    VM#:        17957
AGENCY:                  National Ocean Service (NOS)          IDB PID#:  DN8623
SETTING CLASSIFICATION:  Concrete manhole                      OPUS PID:        
LATITUDE:   18° 18.1' N (  18.30106)          LONGITUDE:  65° 18.1' W ( -65.30200)


The bench mark is a disk set flush in concrete 11.4 m (37.4 ft) SE of a concrete
structure corner, 9.9 m (32.5 ft) SW of Ricky's Service Station, 5.97 m (19.6
ft) SE of a concrete power pole, 3.10 m (10.2 ft) NE of the water's edge, and
2.12 m (7.0 ft) west of the east face of the Garaje Ricky building.



                         BENCH MARK STAMPING:  2235 F 2006
                         DESIGNATION:          975 2235 F

MONUMENTATION:           Tidal Station disk                    VM#:        18237
AGENCY:                  National Ocean Service (NOS)          IDB PID#:  DN8626
SETTING CLASSIFICATION:  Sidewalk                              OPUS PID:        
LATITUDE:   18° 18.1' N (  18.30181)          LONGITUDE:  65° 18.2' W ( -65.30261)


The BM is a disk set flush in the concrete sidewalk on the NW side of the ramp
by some concrete benches, located 29.05 m (95.31 ft) NW of BM 2235 E, 23.73 m
(77.8 ft) WNW of the center of the road leading into town, 11.49 m (37.7 ft)
west of the center of some concrete steps leading to the water, and 0.65 m (2.1
ft) south of a concrete wall.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  6

                                                                                
Station ID: 9752235                         PUBLICATION DATE:  06/03/2020
Name:       CULEBRA                                           
            PR
NOAA Chart: 25653                           Latitude:   18° 18.1' N (  18.30086)
USGS Quad:  CULEBRA AND ADJACENT ISLANDS    Longitude:  65° 18.1' W ( -65.30247)


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


                         BENCH MARK STAMPING:  2235 G 2007
                         DESIGNATION:          975 2235 G

MONUMENTATION:           Tidal Station disk                    VM#:        18308
AGENCY:                  National Ocean Service (NOS)          IDB PID#:  DN8627
SETTING CLASSIFICATION:  Sidewalk                              OPUS PID:        
LATITUDE:   18° 18.1' N (  18.30189)          LONGITUDE:  65° 18.1' W ( -65.30231)


The bench mark is a disk set flush in a concrete slab near a concrete wall 0.55
m (1.8 ft) high, 4.5 m (14.8 ft) long, running north and south and splitting the
sidewalk by the Bienvenidos A Culebra building, 22.0 m (72.2 ft) west of the
center line of the road leading to the cargo ferry ramp, 7.9 m (25.9 ft) NE of a
light pole, 6.7 m (22.0 ft) NW of a tree, and 1.9 m (6.2 ft) north of the PR-250
curb and gutter.



                         BENCH MARK STAMPING:  2235 H 2008
                         DESIGNATION:          975 2235 H

MONUMENTATION:           Tidal Station disk                    VM#:        18683
AGENCY:                  National Ocean Service (NOS)          IDB PID#:  DN8628
SETTING CLASSIFICATION:  Step                                  OPUS PID:        
LATITUDE:   18° 18.1' N (  18.30192)          LONGITUDE:  65° 18.1' W ( -65.30194)


The benchmark is a disk set in a concrete slab footing and step of the Culebra
Pissa on the SW side of the Isla del Culebra Pissa ve Pizza, 19.67 m (64.5 ft)
south from the south side of the Golden China, 6.27 m (20.6 ft) east from the
center line of Rt. Este 250, 0.33 m (1.08 ft) north from the SW end of Isla del
Culebra Pizza, and 0.20 m (0.66 ft) above the ground.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  6

                                                                                
Station ID: 9752235                         PUBLICATION DATE:  06/03/2020
Name:       CULEBRA                                           
            PR
NOAA Chart: 25653                           Latitude:   18° 18.1' N (  18.30086)
USGS Quad:  CULEBRA AND ADJACENT ISLANDS    Longitude:  65° 18.1' W ( -65.30247)


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


                         BENCH MARK STAMPING:  2235 K 2009
                         DESIGNATION:          975 2235 K

MONUMENTATION:           Tidal Station disk                    VM#:        19224
AGENCY:                  National Ocean Service (NOS)          IDB PID#:  DO1533
SETTING CLASSIFICATION:  Sidewalk                              OPUS PID#: DO1533
LATITUDE:   18° 18.2' N (  18.30261)          LONGITUDE:  65° 18.1' W ( -65.30133)


The bench mark is a disk set in a concrete slab next to a set of three steps
leading to a church on SR-250, 7.43 m (24.38 ft) NNW of the centerline of
SR-250, 4.78 m (15.68 ft) NNE of the north face of a wall of the church that
runs east and west parallel to SR-250, .20 m (0.66 ft) SSE of the east face of a
wall that runs east and west parallel to SR- 250 and next to a church, .17 m
(0.56 ft) SSW of a set of concrete steps leading to a church courtyard, 0.06 m
(0.20 ft) above the road on SR-250, set in a concrete sidewalk and flush with
the ground.



                         BENCH MARK STAMPING:  2235 M 2019
                         DESIGNATION:          975 2235 M

MONUMENTATION:           Bench Mark disk                       VM#:        23033
AGENCY:                  National Ocean Service                IDB PID:         
SETTING CLASSIFICATION:  Bridge abutment                       OPUS PID:        
LATITUDE:   18° 18.1' N (  18.30219)          LONGITUDE:  65° 18.0' W ( -65.29989)


The benchmark is brass disk set flush in the NW bridge abutment of the bridge
located along Cll Escudero. The disk is 10.30 m (33.8 ft) west of the west face
of the NE bridge abutment, 1.20 m (3.9 ft) east of the west edge of the NW
bridge abutment, and 0.18 m (2.6 ft) north of the south face of the NW bridge
abutment.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  6

                                                                                
Station ID: 9752235                         PUBLICATION DATE:  06/03/2020
Name:       CULEBRA                                           
            PR
NOAA Chart: 25653                           Latitude:   18° 18.1' N (  18.30086)
USGS Quad:  CULEBRA AND ADJACENT ISLANDS    Longitude:  65° 18.1' W ( -65.30247)


                            T I D A L   D A T U M S 


Tidal datums at CULEBRA based on:

     LENGTH OF SERIES:      6 YEARS
     TIME PERIOD:           6/06-5/09, 2/12-1/13, 4/16-3/17, 4/18-3/19
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  9755371 SAN JUAN, LA PUNTILLA, SAN JUAN BAY


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

     HIGHEST OBSERVED WATER LEVEL (09/20/2017)         =  0.666
     MEAN HIGHER HIGH WATER                     MHHW   =  0.343
     MEAN HIGH WATER                            MHW    =  0.280
     MEAN TIDE LEVEL                            MTL    =  0.165
     MEAN SEA LEVEL                             MSL    =  0.165
     Puerto Rico Vertical Datum of 2002         PRVD02 =  0.154
     MEAN LOW WATER                             MLW    =  0.050
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (04/28/2009)         = -0.187



Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     2235 D 2005                                 1.127    0.847
     2235 B 2005                                 1.722    1.442
     2235 C 2005                                 1.715    1.435
     2235 F 2006                                 2.945    2.665
     2235 G 2007                                 3.792    3.512
     2235 H 2008                                 4.564    4.284
     2235 K 2009                                 2.032    1.752
     2235 M 2019                                 3.271    2.990


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

                                                                                
Station ID: 9752235                         PUBLICATION DATE:  06/03/2020
Name:       CULEBRA                                           
            PR
NOAA Chart: 25653                           Latitude:   18° 18.1' N (  18.30086)
USGS Quad:  CULEBRA AND ADJACENT ISLANDS    Longitude:  65° 18.1' W ( -65.30247)


                             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 any other fixed island datum.

This tide station location has a defined island datum (PRVD02).  Island datums
are specific fixed geodetic datums whose elevation relationship 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 PRVD02 elevation is shown on the Elevations of Tidal Datums Table Referred
to MLLW only when two or more of the bench marks listed have PRVD02 elevations.
The PRVD02 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, PRVD02 bench mark elevations computed indirectly from the tidal
datums elevation table may differ slightly from PRVD02 elevations listed for
each bench mark in the NGS database.