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

                                                                                
Station ID: 8720596                         PUBLICATION DATE:  11/24/2009
Name:       EAST TOCOI, ST. JOHNS RIVER                       
            FL
NOAA Chart: 114955                          Latitude:   29° 51.5' N (  29.85830)
USGS Quad:  RIVERDALE                       Longitude:  81° 33.2' W ( -81.55330)


To reach the bench marks from the intersection of U.S. Highway 1 and State Road
C-214 in St. Augustine, proceed west on State Road 214 for 25.1 km (15.6 mi) to
State Road 13, proceed north on State Road 13 for 1.4 km (0.9 mi) to the Tocoi
Fish Camp on the west side of the highway.  The bench marks are along State
Roads 13 and C-214.  The tide station were at the NW corner of the southernmost
dock at the fish camp.


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


                 PRIMARY BENCH MARK STAMPING:  0596 C 1978
                         DESIGNATION:          872 0596 C TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         5223
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AQ2634
SETTING CLASSIFICATION:  Concrete headwall                     OPUS PID:        
LATITUDE:   29° 50.9' N (  29.84889)          LONGITUDE:  81° 33.4' W ( -81.55694)


The primary bench mark is a disk set flush in the north end of the culvert
headwall, in the north end of a drainage culvert headwall on the east side of
the highway in front of the residence at 13860 State Road 13, 402.34 m (1320.0
ft) NNE of bench mark No 3 1934, 17.07 m (56.0 ft) south of the centerline of a
driveway leading to the residence at 13860 State Road 13, 10.33 m (33.9 ft) NW
of a 1.22 m (4.0 ft) wire and wood fence corner, 7.01 m (23.0 ft) east of the
centerline of State Road 13, 25.91 m (85.0 ft) east of the St. Johns River, and
7.25 m (23.8 ft) NNW of wood power pole No. 34450 6588 09 with a transformer
attached and 5.15 m (16.9 ft) NW of a guy wire.

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

                                                                                
Station ID: 8720596                         PUBLICATION DATE:  11/24/2009
Name:       EAST TOCOI, ST. JOHNS RIVER                       
            FL
NOAA Chart: 114955                          Latitude:   29° 51.5' N (  29.85830)
USGS Quad:  RIVERDALE                       Longitude:  81° 33.2' W ( -81.55330)


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


                         BENCH MARK STAMPING:  NO 1 1934
                         DESIGNATION:          872 0596 TIDAL 1

MONUMENTATION:           Tidal Station disk                    VM#:         5219
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  AQ2632
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID#: AQ2632
LATITUDE:   29° 50.7' N (  29.84467)          LONGITUDE:  81° 33.5' W ( -81.55850)


The bench mark is a disk set flush in the top of a 0.30 m (1.0 ft) square
concrete monument projecting 0.18 m (0.6 ft) above the level of the ground, at
the SE corner of State Road 13 and County Road 214, 16.03 m (52.6 ft) east of
the centerline of State Road 13, 14.75 m (48.4 ft) south of the centerline of
County Road 214, 5.58 m (18.3 ft) west of a 0.15 m by 0.15 m (6.0 in by 6.0 in)
SRD concrete right of way marker that projects 45.72 cm (18.0 in) above ground,
1.31 m (4.3 ft) south of a power pole with a transformer box number P65
attached, and 0.98 m (3.2 ft) west of a carsonite witness post.  



                         BENCH MARK STAMPING:  NO 3 1934
                         DESIGNATION:          872 0596 TIDAL 3

MONUMENTATION:           Tidal Station disk                    VM#:         5220
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  AQ2633
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   29° 50.7' N (  29.84575)          LONGITUDE:  81° 33.5' W ( -81.55797)


The bench mark is a disk set flush in the top of a 0.30 m (1.0 ft) square
concrete monument which is projecting 0.12 m (0.4 ft) above ground level, north
of the intersection of State Roads 13 and C-214, 118.26 m (388.0 ft) north of
the centerline of County Road 214, 49.68 m (163.0 ft) NNE of the north end of
the east headwall of a culvert under the highway, 14.33 m (47.0 ft) east of the
centerline of State Road 13, and 0.30 m (1.0 ft) south of a carsonite witness
post..     

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

                                                                                
Station ID: 8720596                         PUBLICATION DATE:  11/24/2009
Name:       EAST TOCOI, ST. JOHNS RIVER                       
            FL
NOAA Chart: 114955                          Latitude:   29° 51.5' N (  29.85830)
USGS Quad:  RIVERDALE                       Longitude:  81° 33.2' W ( -81.55330)


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


                         BENCH MARK STAMPING:  STJ 11 1984 BSM
                         DESIGNATION:          STJ 11

MONUMENTATION:           Tidal Station disk                    VM#:        19379
AGENCY:                  FL Department of Natural Resources
                         (FLDNR)                               IDB PID#:  AQ2630
SETTING CLASSIFICATION:  Culvert headwall                      OPUS PID:        
LATITUDE:   29° 49.5' N (  29.82444)          LONGITUDE:  81° 33.2' W ( -81.55333)


The bench mark is a disk set flush in the top of the culvert headwall, 0.30 m
(1.0 ft) below the level of State Road 13, 5.12 m (16.8 ft) east of the
centerline of State Road 13, and 0.30 m (1.0 ft) south of the north end of the
culvert headwall.  



                         BENCH MARK STAMPING:  STJ 12
                         DESIGNATION:           STJ 12
                         ALIAS:                 

MONUMENTATION:           Tidal Station disk                    VM#:        19380
AGENCY:                  FL Department of Transportation (FLDT) IDB PID#:  AQ2631
SETTING CLASSIFICATION:  Bridge guardrail                      OPUS PID:        
LATITUDE:   29° 50.1' N (  29.83500)          LONGITUDE:  81° 33.2' W ( -81.55389)


The bench mark is a disk set flush in the top of the bridge guardrail on the SW
corner of the bridge, 5.09 m (16.7 ft) west of the centerline of State Road 13,
and 0.91 m (3.0 ft) above the level of State Road 13.  

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

                                                                                
Station ID: 8720596                         PUBLICATION DATE:  11/24/2009
Name:       EAST TOCOI, ST. JOHNS RIVER                       
            FL
NOAA Chart: 114955                          Latitude:   29° 51.5' N (  29.85830)
USGS Quad:  RIVERDALE                       Longitude:  81° 33.2' W ( -81.55330)


                            T I D A L   D A T U M S 


Tidal datums at EAST TOCOI, ST. JOHNS RIVER based on:

     LENGTH OF SERIES:      3 MONTHS
     TIME PERIOD:           September 1978 - November 1978
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8720496 GREEN COVE SPRINGS, ST. JOHNS R.


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

     MEAN HIGHER HIGH WATER                     MHHW   =  0.325
     MEAN HIGH WATER                            MHW    =  0.302
     MEAN TIDE LEVEL                            MTL    =  0.158
     MEAN SEA LEVEL                             MSL    =  0.157
     North American Vertical Datum              NAVD88 =  0.143
     MEAN LOW WATER                             MLW    =  0.013
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     0596 C 1978                                 3.348    3.046
     NO 1 1934                                   2.887    2.585
     NO 3 1934                                   3.114    2.813
     STJ 11 1984 BSM                             1.070    0.768
     STJ 12                                      3.232    2.930


Foot Notes:

Geodetic heights of the bench marks meet all NOAA/NOS/NGS quality control
standards for Second Order, Class 1 leveling.  It is advised that a confirmation
set of levels be established for bench marks STJ 11 1984 BSM and STJ 12 to
verify height differences before using tidal bench mark elevation information.

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

                                                                                
Station ID: 8720596                         PUBLICATION DATE:  11/24/2009
Name:       EAST TOCOI, ST. JOHNS RIVER                       
            FL
NOAA Chart: 114955                          Latitude:   29° 51.5' N (  29.85830)
USGS Quad:  RIVERDALE                       Longitude:  81° 33.2' W ( -81.55330)


                             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.