U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Datums Page Page 1 of 5 Station ID: 9414525 PUBLICATION DATE: 04/29/2003 Name: PALO ALTO YACHT HARBOR, S. F. BAY CA NOAA Chart: 18651 Latitude: 37° 27.5' N ( 37.45830) USGS Quad: MOUNTAIN VIEW Longitude: 122° 6.3' W (-122.10500) To reach the tidal bench marks fron the Embarcadero Road exit on U.S. Highway 101, proceed NE on Embarcadero Road for 1.9 km (1.2 mi) to Palo Alto Yacht Harbor. The bench marks are near the harbor. The tide gage and staff were located opposite Slip #13. T I D A L B E N C H M A R K S
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 2 of 5 Station ID: 9414525 PUBLICATION DATE: 04/29/2003 Name: PALO ALTO YACHT HARBOR, S. F. BAY CA NOAA Chart: 18651 Latitude: 37° 27.5' N ( 37.45830) USGS Quad: MOUNTAIN VIEW Longitude: 122° 6.3' W (-122.10500) T I D A L B E N C H M A R K S PRIMARY BENCH MARK STAMPING: TIDAL 7 PA 1965 DESIGNATION: TIDAL 7 MONUMENTATION: Tidal Station disk VM#: 8327 AGENCY: US Coast and Geodetic Survey (USC&GS) IDB PID#: HT1274 SETTING CLASSIFICATION: Concrete foundation OPUS PID#: HT1274 LATITUDE: 37° 27.4' N ( 37.45670) LONGITUDE: 122° 6.4' W (-122.10700) The primary bench mark is a disk set on the rim at the SW corner of the foundation for the fountain pool at the duck pond at the yacht harbor, on the east side of the pond, 91 m (300 ft) north of the road, 15 m (50 ft) NNW of the migratory bird sanctuary sign post, 4 m (12 ft) east of the pond rim.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 3 of 5 Station ID: 9414525 PUBLICATION DATE: 04/29/2003 Name: PALO ALTO YACHT HARBOR, S. F. BAY CA NOAA Chart: 18651 Latitude: 37° 27.5' N ( 37.45830) USGS Quad: MOUNTAIN VIEW Longitude: 122° 6.3' W (-122.10500) T I D A L B E N C H M A R K S BENCH MARK STAMPING: TIDAL 8 PA 1965 DESIGNATION: TIDAL 8 MONUMENTATION: Tidal Station disk VM#: 8328 AGENCY: US Coast and Geodetic Survey (USC&GS) IDB PID#: HT1273 SETTING CLASSIFICATION: Spit OPUS PID: LATITUDE: 37° 27.4' N ( 37.45670) LONGITUDE: 122° 6.6' W (-122.11000) The bench mark is a disk set in the rim of the duck pond at the yacht harbor, on the north side of the pond and at the west end of the spit, 9 m (30 ft) east of the terminus of a cyclone fence, 3.81 m (12.5 ft) east of a right angle change in direction of the duck pond bulkhead, and 0.18 m (0.6 ft) from the end of the spit. BENCH MARK STAMPING: 4525 C 1976 DESIGNATION: 941 4525 C MONUMENTATION: Tidal Station disk VM#: 8330 AGENCY: National Ocean Survey (NOS) IDB PID#: SETTING CLASSIFICATION: Unspecified rod OPUS PID: LATITUDE: 37° 27.5' N ( 37.45830) LONGITUDE: 122° 6.3' W (-122.10500) The bench mark is a disk located 43 m (140 ft) east of the harbormasters office front door, 25 m (83 ft) north of north post of Gate B-2 of Palo Alto Yacht Harbor, 21 m (70 ft) east of the centerline of the Palo Alto Yacht Harbor ramp road, 2 m (6 ft) west of the outer edge of the sand banked sea wall on the west side of Palo Alto Yacht Harbor, and 0.85 m (2.8 ft) north of power pole # 26Y with witness post marker. The bench mark is set at ground level, crimped to the top of an unspecified rod driven 9.8 m (32 ft), and encased in a PVC pipe.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 4 of 5 Station ID: 9414525 PUBLICATION DATE: 04/29/2003 Name: PALO ALTO YACHT HARBOR, S. F. BAY CA NOAA Chart: 18651 Latitude: 37° 27.5' N ( 37.45830) USGS Quad: MOUNTAIN VIEW Longitude: 122° 6.3' W (-122.10500) T I D A L D A T U M S Tidal datums at PALO ALTO YACHT HARBOR, S. F. BAY based on: LENGTH OF SERIES: 7 MONTHS TIME PERIOD: June 1984 - December 1984 TIDAL EPOCH: 1983-2001 CONTROL TIDE STATION: 9414750 ALAMEDA, SAN FRANCISCO BAY Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS: MEAN HIGHER HIGH WATER MHHW = 2.321 MEAN HIGH WATER MHW = 2.130 MEAN TIDE LEVEL MTL = 1.182 MEAN SEA LEVEL MSL = 1.149 MEAN LOW WATER MLW = 0.234 MEAN LOWER LOW WATER MLLW = 0.000 North American Vertical Datum (NAVD88) Bench Mark Elevation Information In METERS above: Stamping or Designation MLLW MHW TIDAL 7 PA 1965 2.307 0.177 TIDAL 8 PA 1965 2.048 -0.082 4525 C 1976 2.940 0.810
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 5 of 5 Station ID: 9414525 PUBLICATION DATE: 04/29/2003 Name: PALO ALTO YACHT HARBOR, S. F. BAY CA NOAA Chart: 18651 Latitude: 37° 27.5' N ( 37.45830) USGS Quad: MOUNTAIN VIEW Longitude: 122° 6.3' W (-122.10500) 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.