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

                                                                                
Station ID: 9411399                         PUBLICATION DATE:  05/10/2013
Name:       GAVIOTA STATE PARK, PACIFIC OCEAN                 
            CA
NOAA Chart: 18721                           Latitude:   34° 28.2' N (  34.46939)
USGS Quad:  GAVIOTA                         Longitude: 120° 13.7' W (-120.22831)


To reach the station from the intersection of Highways 1 and 101 29 km (18 mi)
SE of Lompoc, proceed southerly on Highway 101 for 3.9 km (2.4 mi) to the
intersection with Gaviota Beach Road, turn right on Gaviota Beach Road and
proceed south 0.5 km (0.3 mi) to the Gaviota State Park entrance, continue 0.2
km (0.1 mi) south into the parking lot, park and continue SW on foot beneath a
train trestle along the paved road 0.1 km (0.06 mi) to the wooden pier.  The
benchmarks are located throughout the parking area and along an abandoned
highway to the north near Highway 101.  The tide gauge is located 130 m (425 ft)
from the base of the pier.


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


                 PRIMARY BENCH MARK STAMPING:  1399 A 2012
                         DESIGNATION:          941 1399 A

MONUMENTATION:           Tidal Station disk                    VM#:        20623
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete base of pier                 OPUS PID#: BBCW94
LATITUDE:   34° 28.3' N (  34.47089)          LONGITUDE: 120° 13.7' W (-120.22868)


The primary bench mark is a disk set in a 0.58 m (1.9 ft) thick concrete slab on
top of bedrock at the base of the Gaviota State Park pier, 33.89 m (111.2 ft) SW
from the north end of the metal railing on the east side of the path near the
trestle, 9.95 m (32.6 ft) WNW from the NE corner of the wooden pier, 4.21 m
(13.8 ft) NW from the NW corner of the wooden pier, 0.15 m (0.5 ft) NE of the
concrete edge, and 0.14 m (0.5 ft) WSW from the metal railing.

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

                                                                                
Station ID: 9411399                         PUBLICATION DATE:  05/10/2013
Name:       GAVIOTA STATE PARK, PACIFIC OCEAN                 
            CA
NOAA Chart: 18721                           Latitude:   34° 28.2' N (  34.46939)
USGS Quad:  GAVIOTA                         Longitude: 120° 13.7' W (-120.22831)


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


                         BENCH MARK STAMPING:  1399 B 2012
                         DESIGNATION:          941 1399 B

MONUMENTATION:           Tidal Station disk                    VM#:        20624
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete curb                         OPUS PID:        
LATITUDE:   34° 28.3' N (  34.47186)          LONGITUDE: 120° 13.7' W (-120.22833)


The bench mark is a disk set in a concrete curb adjacent to the storage building
for the Gaviota Beach Store, 52.35 m (171.8 ft) NNW of the fourth support east
of the west end of the train trestle, 29.05 m (95.3 ft) east of a metal light
pole, 4.75 m (15.6 ft) SE of a stop sign, 0.27 m (0.9 ft) WSW from the SW corner
of the storage building and 0.18 m (0.6 ft) above the asphalt parking lot.



                         BENCH MARK STAMPING:  1399 C 2012
                         DESIGNATION:          941 1399 C

MONUMENTATION:           Tidal Station disk                    VM#:        20625
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete curb                         OPUS PID:        
LATITUDE:   34° 28.4' N (  34.47300)          LONGITUDE: 120° 13.8' W (-120.22942)


The bench mark is a disk set in the concrete curb to the entrance kiosk for the
Gaviota State Beach Park, 41.35 m (135.7 ft) NW of the NW corner of the shower
building, 37.81 m (124.0 ft) south of the centerline of the entrance gate to the
park, 10.06 m (33.0 ft) ESE of a stop sign on the west side of the road at the
kiosk, 3.92 m (12.9 ft) south of the SW corner of the kiosk and 0.06 m (0.2 ft)
above the asphalt road.

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

                                                                                
Station ID: 9411399                         PUBLICATION DATE:  05/10/2013
Name:       GAVIOTA STATE PARK, PACIFIC OCEAN                 
            CA
NOAA Chart: 18721                           Latitude:   34° 28.2' N (  34.46939)
USGS Quad:  GAVIOTA                         Longitude: 120° 13.7' W (-120.22831)


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


                         BENCH MARK STAMPING:  R 27 RESET 1957
                         DESIGNATION:          R 27 RESET

MONUMENTATION:           Survey disk                           VM#:        20626
AGENCY:                  CA State Lands Commission             IDB PID#:  DZ0047
SETTING CLASSIFICATION:  Bridge abutment                       OPUS PID:        
LATITUDE:   34° 28.3' N (  34.47133)          LONGITUDE: 120° 13.7' W (-120.22861)


The bench mark is a disk set on the top of the bridge abutment at the west end
of the railroad trestle over Gaviota State Park, 12.09 m (39.7 ft) east of a No
Trespassing sign, 2.71 m (8.9 ft) north of the south end of the stone abutment
and 0.63 m (2.1 ft) south of the wooden side of the bridge.

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

                                                                                
Station ID: 9411399                         PUBLICATION DATE:  05/10/2013
Name:       GAVIOTA STATE PARK, PACIFIC OCEAN                 
            CA
NOAA Chart: 18721                           Latitude:   34° 28.2' N (  34.46939)
USGS Quad:  GAVIOTA                         Longitude: 120° 13.7' W (-120.22831)


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


                         BENCH MARK STAMPING:  M 761 1948
                         DESIGNATION:          M 761

MONUMENTATION:           Bench Mark disk                       VM#:        20627
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  DZ0045
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   34° 28.3' N (  34.47133)          LONGITUDE: 120° 13.7' W (-120.22861)


The bench mark is a disk set in the top of a concrete monument, 48.53 m (159.2
ft) SSW of the shoulder of Highway 101 measured along the trail, 13.22 m (43.4
ft) WSW of the centerline of the abandoned highway right of way, 7.19 m (23.6
ft) SSW of power pole 949 675-E, 0.40 m (1.3 ft) ENE of a metal witness post and
0.18 m (0.6 ft) above the ground.

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

                                                                                
Station ID: 9411399                         PUBLICATION DATE:  05/10/2013
Name:       GAVIOTA STATE PARK, PACIFIC OCEAN                 
            CA
NOAA Chart: 18721                           Latitude:   34° 28.2' N (  34.46939)
USGS Quad:  GAVIOTA                         Longitude: 120° 13.7' W (-120.22831)


                            T I D A L   D A T U M S 


Tidal datums at GAVIOTA STATE PARK, PACIFIC OCEAN based on:

     LENGTH OF SERIES:      3 MONTHS
     TIME PERIOD:           December 2012 - February 2013
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  9411340 SANTA BARBARA, PACIFIC OCEAN


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

     MEAN HIGHER HIGH WATER                     MHHW   =  1.611
     MEAN HIGH WATER                            MHW    =  1.387
     MEAN TIDE LEVEL                            MTL    =  0.842
     MEAN SEA LEVEL                             MSL    =  0.837
     MEAN LOW WATER                             MLW    =  0.297
     North American Vertical Datum              NAVD88 =  0.028
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     1399 A 2012                                 6.710    5.323
     1399 B 2012                                 4.063    2.676
     1399 C 2012                                 4.722    3.335
     R 27 RESET 1957                            25.138   23.751
     M 761 1948                                 35.175   33.788


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

                                                                                
Station ID: 9411399                         PUBLICATION DATE:  05/10/2013
Name:       GAVIOTA STATE PARK, PACIFIC OCEAN                 
            CA
NOAA Chart: 18721                           Latitude:   34° 28.2' N (  34.46939)
USGS Quad:  GAVIOTA                         Longitude: 120° 13.7' W (-120.22831)


                             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.