U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  7

                                                                                
Station ID: 9410580                         PUBLICATION DATE:  04/21/2003
Name:       NEWPORT BEACH, NEWPORT BAY ENTRANCE               
            CA
NOAA Chart: 18754                           Latitude:   33° 36.2' N (  33.60330)
USGS Quad:  NEWPORT BEACH                   Longitude: 117° 53.0' W (-117.88300)


To reach the tidal bench marks from the Jamboree/Corona Del Mar exit of U.S.
Interstate 405, proceed 8.8 km (5.5 mi) SW on Jamboree Road to Bayside Drive,
then 1.1 km (0.7 mi) SE to the Orange County Harbor District Office grounds
entrance at 1901 Bayside Drive.  The bench marks are on the grounds and along
Bayside Drive.  The tide gage was located on the Orange County Harbor District
Office pier.


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


                 PRIMARY BENCH MARK STAMPING:  1 NP 1955
                         DESIGNATION:          941 0580 TIDAL 1 NP

MONUMENTATION:           Bench Mark disk                       VM#:          912
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  DX1968
SETTING CLASSIFICATION:  Concrete flagpole base                OPUS PID:        
LATITUDE:   33° 36.2' N (  33.60330)          LONGITUDE: 117° 53.1' W (-117.88500)


The primary bench mark is a disk set in the concrete flagpole base at Orange
County Harbor District Office, 29.29 m (96.1 ft) SW of bench mark 0580 N 1977,
17 m (56 ft) NE of the north corner of a boat shop, and 0.61 m (2.0 ft) NW of
the flagpole.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  7

                                                                                
Station ID: 9410580                         PUBLICATION DATE:  04/21/2003
Name:       NEWPORT BEACH, NEWPORT BAY ENTRANCE               
            CA
NOAA Chart: 18754                           Latitude:   33° 36.2' N (  33.60330)
USGS Quad:  NEWPORT BEACH                   Longitude: 117° 53.0' W (-117.88300)


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


                         BENCH MARK STAMPING:  2 NP 1955
                         DESIGNATION:          941 0580  TIDAL 2 NP

MONUMENTATION:           Bench Mark disk                       VM#:          915
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  DX1969
SETTING CLASSIFICATION:  Concrete sea wall                     OPUS PID#: DX1969
LATITUDE:   33° 36.2' N (  33.60330)          LONGITUDE: 117° 53.1' W (-117.88500)


The bench mark is a disk set in the concrete sea wall on the Orange County
Harbor District Office grounds, 62 m (204 ft) NW of bench mark COORS 1974
TOPOGRAPHIC, 6.49 m (21.3 ft) south of the south corner of the Sheriff Harbor
Patrol office, 0.76 m (2.5 ft) NW of the NW wall of a marine railway, and 0.46 m
(1.5 ft) east of the west edge of the sea wall.



                         BENCH MARK STAMPING:  3 NP 1955
                         DESIGNATION:          941 0580 TIDAL 3 NP

MONUMENTATION:           Bench Mark disk                       VM#:          916
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  DX1970
SETTING CLASSIFICATION:  Concrete sea wall                     OPUS PID:        
LATITUDE:   33° 36.2' N (  33.60330)          LONGITUDE: 117° 53.1' W (-117.88500)


The bench mark is a disk set in the concrete sea wall on the Orange County
Harbor District Office grounds, 69 m (226 ft) NW of bench mark 2 NP 1955, 21.31
m (69.9 ft) NW of the west corner of the Sheriff Harbor Patrol office, 13.69 m
(44.9 ft) SW of the SW wall of a shop building, and 1.10 m (3.6 ft) SE of a
chain link fence.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  7

                                                                                
Station ID: 9410580                         PUBLICATION DATE:  04/21/2003
Name:       NEWPORT BEACH, NEWPORT BAY ENTRANCE               
            CA
NOAA Chart: 18754                           Latitude:   33° 36.2' N (  33.60330)
USGS Quad:  NEWPORT BEACH                   Longitude: 117° 53.0' W (-117.88300)


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


                         BENCH MARK STAMPING:  6 NP 1959
                         DESIGNATION:          941 0580 TIDAL 6 NP

MONUMENTATION:           Bench Mark disk                       VM#:          917
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  DX1967
SETTING CLASSIFICATION:  Concrete curb                         OPUS PID:        
LATITUDE:   33° 36.2' N (  33.60330)          LONGITUDE: 117° 53.1' W (-117.88500)


The bench mark is a disk set in the SW curb of the entrance to Orange County
Harbor District Office, 7.89 m (25.9 ft) SE of the centerline of the entrance
road, 6.10 m (20.0 ft) SE of the centerline of Bayside Drive, 4.60 m (15.1 ft)
NW of the NW edge of a driveway to the residence at 1915 Bayside Drive, 3.66 m
(12.0 ft) east of a fire hydrant, and 0.18 m (0.6 ft) above road level.



                         BENCH MARK STAMPING:  0580 L 1977
                         DESIGNATION:          941 0580 L TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:          918
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  DX3418
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   33° 36.4' N (  33.60670)          LONGITUDE: 117° 53.1' W (-117.88500)


The bench mark is a disk set near the south end of a curve on the east side of
Bayside Drive, opposite the residence at 1645 Bayside Drive, 16.61 m (54.5 ft)
NE of a fire hydrant, 6.80 m (22.3 ft) east of the centerline of Bayside Drive,
3.29 m (10.8 ft) south of utility pole #3503, 0.34 m (1.1 ft) west of a metal
witness post, and 0.21 m (0.7 ft) east of the east edge of a sidewalk.  The
bench mark is set 0.06 m (0.2 ft) above grade, crimped to a copper-clad steel
rod driven 4.90 m (16 ft), and encased in a 4-inch PVC pipe and concrete
kickblock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  7

                                                                                
Station ID: 9410580                         PUBLICATION DATE:  04/21/2003
Name:       NEWPORT BEACH, NEWPORT BAY ENTRANCE               
            CA
NOAA Chart: 18754                           Latitude:   33° 36.2' N (  33.60330)
USGS Quad:  NEWPORT BEACH                   Longitude: 117° 53.0' W (-117.88300)


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


                         BENCH MARK STAMPING:  0580 M 1977
                         DESIGNATION:          941 0580 M TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:          919
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  DX3419
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   33° 36.3' N (  33.60500)          LONGITUDE: 117° 53.1' W (-117.88500)


The bench mark is a disk set on the NE side of Bayside Drive, 0.2 km (0.1 mi) NW
of the entrance to Orange County Harbor District Office, 26.49 m (86.9 ft) NE
and across Bayside Drive from the BALBOA YACHT CLUB sign, 18.11 m (59.4 ft) SE
and across Bayside Drive from the NE corner of a fence surrounding the yacht
club, 7.32 m (24.0 ft) east of the centerline of Bayside Drive, and 0.43 m (1.4
ft) west of a metal witness post.  The bench mark is set 6 cm (0.2 ft) above
grade, crimped to a copper-clad steel rod driven 6.1 m (20 ft), and encased in a
4-inch PVC pipe and concrete kickblock.



                         BENCH MARK STAMPING:  0580 N 1977
                         DESIGNATION:          941 0580 N TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:          920
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  DX3420
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   33° 36.2' N (  33.60330)          LONGITUDE: 117° 53.0' W (-117.88300)


The bench mark is a disk set on the Orange County Harbor District Office
grounds, 34.69 m (113.8 ft) SW of the centerline of Bayside Drive, 28.59 m (93.8
ft) SW of bench mark 6 NP 1959, 26.06 m (85.5 ft) east of a flagpole, 4.60 m
(15.1 ft) SE of the centerline of a driveway, 0.61 m (2.0 ft) SE of the SE curb
of the driveway, and 0.46 m (1.5 ft) north of a metal witness post.  The bench
mark is set 6 cm (0.2 ft) above grade, crimped to a copper-clad steel rod driven
6.7 m (22 ft), and encased in a 4-inch PVC pipe and concrete kickblock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  7

                                                                                
Station ID: 9410580                         PUBLICATION DATE:  04/21/2003
Name:       NEWPORT BEACH, NEWPORT BAY ENTRANCE               
            CA
NOAA Chart: 18754                           Latitude:   33° 36.2' N (  33.60330)
USGS Quad:  NEWPORT BEACH                   Longitude: 117° 53.0' W (-117.88300)


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


                         BENCH MARK STAMPING:  COORS 1974 TOPOGRAPHIC
                         DESIGNATION:          941 0580 TIDAL COORS

MONUMENTATION:           Bench Mark disk                       VM#:          921
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  DX3663
SETTING CLASSIFICATION:  Concrete sea wall                     OPUS PID:        
LATITUDE:   33° 36.2' N (  33.60330)          LONGITUDE: 117° 53.1' W (-117.88500)


The bench mark is a disk set in a concrete sea wall at Orange County Harbor
District Office, about 76 m (250 ft) south of bench mark 1 NP 1955, 19.39 m
(63.6 ft) SE of the east corner of the Coast Guard pier, 4.60 m (15.1 ft) south
of a white Coast Guard signal mast, and 1.10 m (3.6 ft) NW of the SE corner of
the sea wall.



                         BENCH MARK STAMPING:  NB4-41-82
                         DESIGNATION:          941 0580 NB4-41-82

MONUMENTATION:           Bench Mark disk                       VM#:          923
AGENCY:                  Orange County                         IDB PID#:        
SETTING CLASSIFICATION:  Concrete storm drain                  OPUS PID:        
LATITUDE:   33° 26.2' N (  33.43670)          LONGITUDE: 117° 53.0' W (-117.88300)


The bench mark is a disk set flush in the NW corner of a concrete storm drain
fronting the residence at 2137 Bayside Drive, 0.3 km (0.2 mi) east of the
entrance to Orange County Harbor District Office, 10.67 m (35.0 ft) east of the
centerline of the residence driveway, and 0.27 m (0.9 ft) south of the south
curb.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of  7

                                                                                
Station ID: 9410580                         PUBLICATION DATE:  04/21/2003
Name:       NEWPORT BEACH, NEWPORT BAY ENTRANCE               
            CA
NOAA Chart: 18754                           Latitude:   33° 36.2' N (  33.60330)
USGS Quad:  NEWPORT BEACH                   Longitude: 117° 53.0' W (-117.88300)


                            T I D A L   D A T U M S 


Tidal datums at NEWPORT BEACH, NEWPORT BAY ENTRANCE based on:

     LENGTH OF SERIES:      14 Years
     TIME PERIOD:           January 1980 - December 1993
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  9410660 LOS ANGELES, OUTER HARBOR


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

     HIGHEST OBSERVED WATER LEVEL (01/28/1983)         =  2.337
     MEAN HIGHER HIGH WATER                     MHHW   =  1.649
     MEAN HIGH WATER                            MHW    =  1.424
     MEAN TIDE LEVEL                            MTL    =  0.852
     MEAN SEA LEVEL                             MSL    =  0.845
     MEAN LOW WATER                             MLW    =  0.279
     North American Vertical Datum              NAVD88 =  0.055
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (01/20/1988)         = -0.717

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     1 NP 1955                                   3.583    2.159
     2 NP 1955                                   3.280    1.856
     3 NP 1955                                   3.300    1.876
     6 NP 1959                                   4.592    3.168
     0580 L 1977                                 6.395    4.971
     0580 M 1977                                 4.696    3.272
     0580 N 1977                                 4.004    2.580
     COORS 1974 TOPOGRAPHIC                      3.275    1.851
     NB4-41-82                                   3.768    2.344


                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  7 of  7

                                                                                
Station ID: 9410580                         PUBLICATION DATE:  04/21/2003
Name:       NEWPORT BEACH, NEWPORT BAY ENTRANCE               
            CA
NOAA Chart: 18754                           Latitude:   33° 36.2' N (  33.60330)
USGS Quad:  NEWPORT BEACH                   Longitude: 117° 53.0' W (-117.88300)


                             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.