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

                                                                                
Station ID: 8727343                         PUBLICATION DATE:  05/20/2004
Name:       CRYSTAL RIVER, KINGS BAY                          
            FL
NOAA Chart: 11409                           Latitude:   28° 53.9' N (  28.89830)
USGS Quad:  CRYSTAL RIVER                   Longitude:  82° 35.9' W ( -82.59830)


To reach the tidal bench marks from the City Hall in Crystal River, proceed west
on U.S. Highway 19/98 for 0.08 km (0.05 mi) to the Knox Bait House.  The bench
marks are located in the area along U.S. Highway 19/98. The tide gage and staff
were located on the covered wooden dock at the NW corner of the pier at the bait
house.


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


                 PRIMARY BENCH MARK STAMPING:  7343 B 1978
                         DESIGNATION:          872 7343 B TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         7796
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AL7754
SETTING CLASSIFICATION:  Galvanized steel rod                  OPUS PID:        
LATITUDE:   28° 54.0' N (  28.90000)          LONGITUDE:  82° 35.8' W ( -82.59670)


The primary bench mark is a disk located 83 m (273 ft) SW of bench mark 7343 C
1978, 14.78 m (48.5 ft) south of the centerline of U.S. Highway 19/98, 13.72 m
(45.0 ft) east of the centerline of the drive entrance to the parking lot of
Knox Bait House, 11.16 m (36.6 ft) NW of the NW corner of the Old Oyster Bar
Restaurant, and 0.88 m (2.9 ft) south of powerline pole #10098-076007.  The
bench mark is crimped to the top of a galvanized steel rod driven 7.3 m (24 ft)
to refusal, and encased in a PVC pipe and concrete kickblock.

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

                                                                                
Station ID: 8727343                         PUBLICATION DATE:  05/20/2004
Name:       CRYSTAL RIVER, KINGS BAY                          
            FL
NOAA Chart: 11409                           Latitude:   28° 53.9' N (  28.89830)
USGS Quad:  CRYSTAL RIVER                   Longitude:  82° 35.9' W ( -82.59830)


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


                         BENCH MARK STAMPING:  7343 A 1978
                         DESIGNATION:          872 7343 A TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         7795
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AL7755
SETTING CLASSIFICATION:  Concrete walkway                      OPUS PID:        
LATITUDE:   28° 53.9' N (  28.89830)          LONGITUDE:  82° 35.8' W ( -82.59670)


The bench mark is a disk set in a concrete walkway on the east side of the Knox
Bait House, 80 m (262 ft) SW of bench mark 7343 B 1978, 6.10 m (20.0 ft) south
of the NE corner of the building, 5.30 m (17.4 ft) north of the SE corner of the
building, 2.0 m (6.5 ft) west of the edge of the concrete bulkhead, and 0.15 m
(0.5 ft) east of the east side of the building.



                         BENCH MARK STAMPING:  7343 C 1978
                         DESIGNATION:          872 7343 C TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         7797
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AL7753
SETTING CLASSIFICATION:  Concrete culvert head wall            OPUS PID:        
LATITUDE:   28° 54.0' N (  28.90000)          LONGITUDE:  82° 35.7' W ( -82.59500)


The bench mark is a disk set in the top of the east end of a concrete culvert
head wall, 152 m (500 ft) west of bench mark 7343 D 1978, 15.48 m (50.8 ft)
north of the centerline of U.S. Highway 19/98, 12.80 m (42.0 ft) west of the
centerline of 2nd Avenue, 1.16 m (3.8 ft) NE of a lone palm tree, and 0.24 m
(0.8 ft) north of a witness post.

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

                                                                                
Station ID: 8727343                         PUBLICATION DATE:  05/20/2004
Name:       CRYSTAL RIVER, KINGS BAY                          
            FL
NOAA Chart: 11409                           Latitude:   28° 53.9' N (  28.89830)
USGS Quad:  CRYSTAL RIVER                   Longitude:  82° 35.9' W ( -82.59830)


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


                         BENCH MARK STAMPING:  7343 D 1978
                         DESIGNATION:          872 7343 D TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         7798
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AL7752
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   28° 54.0' N (  28.90000)          LONGITUDE:  82° 35.6' W ( -82.59330)


The bench mark is a disk set in the top of a concrete monument, 42 m (138 ft)
west of the SE corner of a shopping center, 33 m (109 ft) south of the SW corner
of the shopping center, 12 m (40 ft) north of the centerline of the highway, 11
m (36 ft) east of the centerline of 1st Avenue, and 0.30 m (1.0 ft) north of
powerline pole #100993-076017 with a witness sign attached.

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

                                                                                
Station ID: 8727343                         PUBLICATION DATE:  05/20/2004
Name:       CRYSTAL RIVER, KINGS BAY                          
            FL
NOAA Chart: 11409                           Latitude:   28° 53.9' N (  28.89830)
USGS Quad:  CRYSTAL RIVER                   Longitude:  82° 35.9' W ( -82.59830)


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


                         BENCH MARK STAMPING:  4.200 7 1935
                         DESIGNATION:          4.200 7
                         ALIAS:                STA 7 1935 EL 4.200

MONUMENTATION:           Tidal Station disk                    VM#:         7799
AGENCY:                  US Army Corps of Engineers (USE)      IDB PID#:  AL7268
SETTING CLASSIFICATION:  Concrete sidewalk                     OPUS PID:        
LATITUDE:   28° 54.0' N (  28.90000)          LONGITUDE:  82° 35.6' W ( -82.59330)


The bench mark is a disk set in top of a concrete sidewalk, 21 m (69 ft) north
of the centerline of the highway, 6.10 m (20.0 ft) west of the centerline of
Citrus Avenue, 3.20 m (10.5 ft) north of a powerline pole, and 2.74 m (9.0 ft)
east of the Lewis Office Supply building

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

                                                                                
Station ID: 8727343                         PUBLICATION DATE:  05/20/2004
Name:       CRYSTAL RIVER, KINGS BAY                          
            FL
NOAA Chart: 11409                           Latitude:   28° 53.9' N (  28.89830)
USGS Quad:  CRYSTAL RIVER                   Longitude:  82° 35.9' W ( -82.59830)


                            T I D A L   D A T U M S 


Tidal datums at CRYSTAL RIVER, KINGS BAY based on:

     LENGTH OF SERIES:      3 MONTHS
     TIME PERIOD:           October 1978 - December 1978
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8727520 CEDAR KEY, GULF OF MEXICO


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

     MEAN HIGHER HIGH WATER                     MHHW   =  0.712
     MEAN HIGH WATER                            MHW    =  0.628
     North American Vertical Datum              NAVD88 =  0.359
     MEAN SEA LEVEL                             MSL    =  0.356
     MEAN TIDE LEVEL                            MTL    =  0.354
     MEAN LOW WATER                             MLW    =  0.080
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     7343 B 1978                                 1.870    1.242
     7343 A 1978                                 1.226    0.598
     7343 C 1978                                 1.599    0.971
     7343 D 1978                                 1.730    1.102
     4.200 7 1935                                1.382    0.754


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

                                                                                
Station ID: 8727343                         PUBLICATION DATE:  05/20/2004
Name:       CRYSTAL RIVER, KINGS BAY                          
            FL
NOAA Chart: 11409                           Latitude:   28° 53.9' N (  28.89830)
USGS Quad:  CRYSTAL RIVER                   Longitude:  82° 35.9' W ( -82.59830)


                             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.