U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 7
Station ID: 9410079 PUBLICATION DATE: 07/27/2017
Name: AVALON, SANTA CATALINA ISLAND
CA
NOAA Chart: 18757 Latitude: 33° 20.7' N ( 33.34500)
USGS Quad: SANTA CATALINA EAST Longitude: 118° 19.5' W (-118.32500)
To reach the tide station from the Avalon ferry terminal on Pebbly Beach Road,
proceed 0.26 km (0.16 mi) SW on Pebbly Beach Road to the intersection with
Crescent Ave, turn right on Crescent Avenue and proceed 0.15 km (0.1 mi) WNW on
Crescent Ave along the waterfront to the intersection with Catalina Avenue at
the base of the Green Pier. The tide station is on Green Pier and the bench
marks are along the waterfront.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 0079 A 2017
DESIGNATION: 941 0079 A
MONUMENTATION: Bench Mark disk VM#: 22200
AGENCY: National Ocean Service IDB PID#:
SETTING CLASSIFICATION: OPUS PID:
LATITUDE: 33° 20.6' N ( 33.34347) LONGITUDE: 118° 19.4' W (-118.32283)
The primary bench mark is a disk set in bed rock outcrop at the base of a rock
cliff on east side of pebbly beach road, 13.47 m (44.2 ft) ESE of the centerline
of road, 11.04 m (36.2 ft) east of light pole, 8.62 m (28.3 ft) south of the
north corner of concrete retaining wall, 6.20 m (20.3 ft) NW of opening of cave,
5.02 m (16.5 ft) ESE of southern most palm tree of three, 4.10 m (13.5 ft) east
of the south corner of cement retaining wall and approximately 2.5 m (8.2 ft)
above the road.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 7
Station ID: 9410079 PUBLICATION DATE: 07/27/2017
Name: AVALON, SANTA CATALINA ISLAND
CA
NOAA Chart: 18757 Latitude: 33° 20.7' N ( 33.34500)
USGS Quad: SANTA CATALINA EAST Longitude: 118° 19.5' W (-118.32500)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: TIDAL 5 1975
DESIGNATION: TIDAL 5 1975
MONUMENTATION: Bench Mark disk VM#: 15680
AGENCY: National Ocean Survey (NOS) IDB PID#:
SETTING CLASSIFICATION: Set in a concrete rectangle OPUS PID:
LATITUDE: 33° 20.6' N ( 33.34281) LONGITUDE: 118° 19.5' W (-118.32447)
The bench mark is a disk set in concrete sidewalk at SE corner of intersection
of Crescent and Clarissa Ave, 3.15 m (10.3 ft) SW of water valve cover in
street, 1.97 m (6.5 ft) SW of water cover in paver sidewalk, 1.92 m (6.3 ft) SW
of building corner, 0.36 m (1.2 ft) SE of edge of curb for Clarissa Avenue, and
0.26 m (0.9 ft) SSW of wooden sign post.
BENCH MARK STAMPING: 0079 B 2017
DESIGNATION: 941 0079 B
MONUMENTATION: Bench Mark disk VM#: 22201
AGENCY: National Ocean Service IDB PID#:
SETTING CLASSIFICATION: Concrete stairway OPUS PID:
LATITUDE: 33° 20.5' N ( 33.34233) LONGITUDE: 118° 19.4' W (-118.32344)
The bench mark is a disk set in middle landing of concrete stairs, 7.82 m (25.7
ft) north of power pole 1492372e, 6.87 m (22.5 ft) SE of light post, 4.39 m
(14.4 ft) NW of top of stairs, 4.10 m (13.5 ft) SE of bottom of stairs, 2.12 m
(7.0 ft) west of palm tree, and 0.2 m (0.7 ft) SSW of concrete and stone
railing.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 7
Station ID: 9410079 PUBLICATION DATE: 07/27/2017
Name: AVALON, SANTA CATALINA ISLAND
CA
NOAA Chart: 18757 Latitude: 33° 20.7' N ( 33.34500)
USGS Quad: SANTA CATALINA EAST Longitude: 118° 19.5' W (-118.32500)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 0079 C 2017
DESIGNATION: 941 0079 C
MONUMENTATION: Bench Mark disk VM#: 22202
AGENCY: National Ocean Service IDB PID#:
SETTING CLASSIFICATION: Concrete seawall OPUS PID:
LATITUDE: 33° 20.6' N ( 33.34339) LONGITUDE: 118° 19.5' W (-118.32503)
The bench mark is a disk set in top of concrete seawall, 11.51 m (37.8 ft) west
of second set of stairs SE of pier through seawall to water, 2.6 m (8.5 ft) NW
of palm tree, 1.96 m (6.4 ft) ESE of the pier, 1.48 m (4.9 ft) ESE of center of
stairs to water adjacent to pier, and 0.39 m (1.3 ft) above beach.
BENCH MARK STAMPING: 0079 D 2017
DESIGNATION: 941 0079 D
MONUMENTATION: Bench Mark disk VM#: 22203
AGENCY: National Ocean Service IDB PID#:
SETTING CLASSIFICATION: Concrete seawall OPUS PID#: BBFL78
LATITUDE: 33° 20.7' N ( 33.34497) LONGITUDE: 118° 19.6' W (-118.32656)
The bench mark is a disk set in a concrete seawall just north of a stone plaza,
41.1 m (134.8 ft) ESE of SE corner of Via Casino Arch over water front walkway,
33.45 m (109.7 ft) SE of stairs down to water, 9.54 m (31.3 ft) NE of concrete
wall at top of beach, and 2.32 m (7.6 ft) NW of higher sea wall.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 7
Station ID: 9410079 PUBLICATION DATE: 07/27/2017
Name: AVALON, SANTA CATALINA ISLAND
CA
NOAA Chart: 18757 Latitude: 33° 20.7' N ( 33.34500)
USGS Quad: SANTA CATALINA EAST Longitude: 118° 19.5' W (-118.32500)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 0079 E 2017
DESIGNATION: 941 0079 E
MONUMENTATION: Bench Mark disk VM#: 22204
AGENCY: National Ocean Service IDB PID#:
SETTING CLASSIFICATION: Concrete headwall for culvert OPUS PID:
LATITUDE: 33° 20.4' N ( 33.34047) LONGITUDE: 118° 19.7' W (-118.32858)
The bench mark is a disk set in concrete headwall for a culvert near the SE
corner of the intersection for Avalon Cyn Rd and Tremont St, 17.25 m (56.6 ft)
south of SE corner of building at 410 Tremont St, 11.59 m (38.0 ft) east of
manhole, 9.65 m (31.7 ft) south of the centerline of Tremont St, 4.74 m (15.6
ft) south of tree, 4.74 m (15.6 ft) SE of curb along Avalon Cyn Rd, and 1.46 m
(4.8 ft) north of chain link fence.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 7
Station ID: 9410079 PUBLICATION DATE: 07/27/2017
Name: AVALON, SANTA CATALINA ISLAND
CA
NOAA Chart: 18757 Latitude: 33° 20.7' N ( 33.34500)
USGS Quad: SANTA CATALINA EAST Longitude: 118° 19.5' W (-118.32500)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 1 RESET 1968
DESIGNATION: TIDAL 1 RESET 1968
MONUMENTATION: Bench Mark disk VM#: 22205
AGENCY: US Coast & Geodetic Survey IDB PID#:
SETTING CLASSIFICATION: Curb OPUS PID:
LATITUDE: 33° 20.6' N ( 33.34269) LONGITUDE: 118° 19.4' W (-118.32383)
The bench mark is a disk set in a section of curb inside of circular traffic
island in intersection of Pebbly Beach Road and Crescent Avenue, 11.68 m (38.3
ft) NNE of corner of Catalina Island cart rentals building, 2.12 m (7.0 ft)
south of palm tree, 1.99 m (6.5 ft) WNW of light pole, 1.97 m (6.5 ft) NNE of
sewer manhole, and 1.05 m (3.4 ft) WSW of closest edge of well cover.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 7
Station ID: 9410079 PUBLICATION DATE: 07/27/2017
Name: AVALON, SANTA CATALINA ISLAND
CA
NOAA Chart: 18757 Latitude: 33° 20.7' N ( 33.34500)
USGS Quad: SANTA CATALINA EAST Longitude: 118° 19.5' W (-118.32500)
T I D A L D A T U M S
Tidal datums at AVALON, SANTA CATALINA ISLAND based on:
LENGTH OF SERIES: 3 MONTHS
TIME PERIOD: February 2017 - April 2017
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:
MEAN HIGHER HIGH WATER MHHW = 1.628
MEAN HIGH WATER MHW = 1.400
MEAN TIDE LEVEL MTL = 0.836
MEAN SEA LEVEL MSL = 0.831
MEAN LOW WATER MLW = 0.271
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
0079 A 2017 6.325 4.925
TIDAL 5 1975 3.139 1.739
0079 B 2017 9.903 8.503
0079 C 2017 3.077 1.677
0079 D 2017 2.768 1.368
0079 E 2017 12.266 10.866
1 RESET 1968 3.822 2.422
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 7 of 7
Station ID: 9410079 PUBLICATION DATE: 07/27/2017
Name: AVALON, SANTA CATALINA ISLAND
CA
NOAA Chart: 18757 Latitude: 33° 20.7' N ( 33.34500)
USGS Quad: SANTA CATALINA EAST Longitude: 118° 19.5' W (-118.32500)
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.