U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Datums Page Page 1 of 6 Station ID: 9447883 PUBLICATION DATE: 06/15/2016 Name: GREENBANK, PUGET SOUND WA NOAA Chart: 18423 Latitude: 48° 6.3' N ( 48.10500) USGS Quad: FREELAND Longitude: 122° 34.2' W (-122.57000) To reach the station from the Washington State Ferry terminal in Clinton on Whidbey Island, proceed 27.0 km (16.8 mi) west and then north on WA 525 to the intersection with North Bluff Road, turn right on North Bluff Road and proceed north 0.5 km (0.3 mi) to the intersection with Wonn Road, turn right on Wonn Road and proceed east 0.1 km (0.07 mi) to the end of the road and the private beach and wooden offshore pilings straight ahead. The tide gauge is on the beach and the bench marks are along Wonn Road and WA 525. T I D A L B E N C H M A R K S PRIMARY BENCH MARK STAMPING: 7883 A 2015 DESIGNATION: 944 7883 A MONUMENTATION: Metal Rod VM#: 21739 AGENCY: CO-OPS IDB PID#: SETTING CLASSIFICATION: Deep Rod Mark OPUS PID: LATITUDE: 48° 6.3' N ( 48.10511) LONGITUDE: 122° 34.4' W (-122.57267) The mark is a flange encased rod set in the lawn N of a shed and S of Wonn Road, 56.35 m (184.9 ft) SE of the centerline of North Bluff Road, 13.48 m (44.2 ft) N of the NW corner of the yellow house at 2909 North Bluff Road, 7.15 m (23.5 ft) NNE of the NE corner of a shed, 6.37 m (20.9 ft) ENE of the NW corner of the shed, 0.90 m (3.0 ft) SW of the N edge of the grass and beginning of the bramble bordering Wonn Road. The datum point is set 2 cm (1 inch) below grade being the top of a stainless steel rod driven 1.2 m (4 ft). to abrupt refusal in glacial till, in a sleeve extending to a depth of 0.9 m (3.0 ft), and encased in a 6 inch NOS logo cover.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 2 of 6 Station ID: 9447883 PUBLICATION DATE: 06/15/2016 Name: GREENBANK, PUGET SOUND WA NOAA Chart: 18423 Latitude: 48° 6.3' N ( 48.10500) USGS Quad: FREELAND Longitude: 122° 34.2' W (-122.57000) T I D A L B E N C H M A R K S BENCH MARK STAMPING: 7883 B 2015 DESIGNATION: 944 7883 B MONUMENTATION: Flange-encased Rod VM#: 21740 AGENCY: CO-OPS IDB PID#: SETTING CLASSIFICATION: OPUS PID#: BBDX65 LATITUDE: 48° 6.3' N ( 48.10570) LONGITUDE: 122° 34.5' W (-122.57422) The bench mark is a flange encased rod set in the lawn S of Greenbank Farm and N of Wonn Road, 22.51 m (73.9 ft) SE of second light pole N of Wonn Road along E side of farm driveway, 19.63 m (64.4 ft) E of a stop sign on W side of farm driveway, 19.02 m (62.4 ft) WNW of a fiber optic pedestal along north side of Wonn Road, 13.75 m (45.1 ft) N of the centerline of Wonn Road, 6.57 m (21.6 ft) ENE of a light pole and 5.28 m (17.3 ft) NE of N post for white Greenbank Farm sign. The datum point is set 6 cm (2 inches) below grade, being the top of a stainless steel rod driven 2.0 m (6.6 ft) to abrupt refusal, in a sleeve extending to a depth of 0.9 m (3.0 ft), and encased in a 6-inch (15 cm) NOS logo cap.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 3 of 6 Station ID: 9447883 PUBLICATION DATE: 06/15/2016 Name: GREENBANK, PUGET SOUND WA NOAA Chart: 18423 Latitude: 48° 6.3' N ( 48.10500) USGS Quad: FREELAND Longitude: 122° 34.2' W (-122.57000) T I D A L B E N C H M A R K S BENCH MARK STAMPING: GP 15525-28 1997 DESIGNATION: GP15525 28 MONUMENTATION: Survey disk VM#: 21741 AGENCY: Washington State Department of Transportation IDB PID#: SETTING CLASSIFICATION: OPUS PID: LATITUDE: 48° 6.1' N ( 48.10242) LONGITUDE: 122° 34.5' W (-122.57519) The mark is a disk in a concrete monument set in the grass along the E side of WA 525, 31.86 m (104.5 ft) NNW of a stop sign at North Bluff Road and WA 525, 28.95 m (95.0 ft) W of a wood power pole on the W side of North Bluff Road, 15.49 m (50.8 ft) NW of the W post of the white Greenbank Farm sign, 3.09 m (10.1 ft) SW of an evergreen tree, and 0.98 m (3.2 ft) SW of a carsonite witness post.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 4 of 6 Station ID: 9447883 PUBLICATION DATE: 06/15/2016 Name: GREENBANK, PUGET SOUND WA NOAA Chart: 18423 Latitude: 48° 6.3' N ( 48.10500) USGS Quad: FREELAND Longitude: 122° 34.2' W (-122.57000) T I D A L B E N C H M A R K S BENCH MARK STAMPING: 7883 C 2015 DESIGNATION: 944 7883 C MONUMENTATION: Flange-encased Rod VM#: 21742 AGENCY: CO-OPS IDB PID#: SETTING CLASSIFICATION: OPUS PID: LATITUDE: 48° 6.4' N ( 48.10589) LONGITUDE: 122° 34.7' W (-122.57767) The mark is a flange encased rod set in the grass field on the N side of Wonn Road, 42.12 m (138.2 ft) NNE of the stop sign at the intersection of Wonn Road and WA 525, 42.01 m (137.8 ft) NNW of the centerline of Wonn Road at the driveway entrance to this field, 27.08 m (88.8 ft) N of the taller of two fiber optic pedestals, 22.95 m (75.3 ft) NE of the NE corner post of the Greenbank farm sign, and 12.34 m (40.5 ft) S of the fence along the S side of a horse pasture. The datum point is set 5 cm (2 inches) below grade being the top of a stainless steel rod driven 1.2 m (4 ft) to abrupt refusal in glacial till, in a sleeve extending to a depth of 0.9 m (3.0 ft), and encased in a 6 inch NOS logo cover. BENCH MARK STAMPING: 944 7883 TIDAL 3 DESIGNATION: 944 7883 TIDAL 3 MONUMENTATION: Bolt VM#: 21744 AGENCY: IDB PID#: SETTING CLASSIFICATION: OPUS PID: LATITUDE: 48° 6.3' N ( 48.10475) LONGITUDE: 122° 34.3' W (-122.57197) The mark is a steel bolt in a concrete monument on the N side of the opening in a stone wall for the path leading to the beach, 18.20 m (59.7 ft) NE of the post at the NW corner of the garage for 794 Wonn Road, 11.83 m (38.8 ft) ENE of the center of the top of a large boulder W of the driveway for 794 Wonn Road, 1.90 m (6.2 ft) N of south stone wall, and 0.50 m (1.6 ft) S of north stone wall.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 5 of 6 Station ID: 9447883 PUBLICATION DATE: 06/15/2016 Name: GREENBANK, PUGET SOUND WA NOAA Chart: 18423 Latitude: 48° 6.3' N ( 48.10500) USGS Quad: FREELAND Longitude: 122° 34.2' W (-122.57000) T I D A L D A T U M S Tidal datums at GREENBANK, PUGET SOUND based on: LENGTH OF SERIES: 3 MONTHS TIME PERIOD: August 2015 - October 2015 TIDAL EPOCH: 1983-2001 CONTROL TIDE STATION: 9447130 SEATTLE, PUGET SOUND Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS: MEAN HIGHER HIGH WATER MHHW = 3.461 MEAN HIGH WATER MHW = 3.196 MEAN TIDE LEVEL MTL = 2.022 MEAN SEA LEVEL MSL = 2.016 MEAN LOW WATER MLW = 0.848 MEAN LOWER LOW WATER MLLW = 0.000 North American Vertical Datum (NAVD88) Bench Mark Elevation Information In METERS above: Stamping or Designation MLLW MHW 7883 A 2015 6.239 3.043 7883 B 2015 10.959 7.763 GP 15525-28 1997 37.676 34.480 7883 C 2015 14.437 11.241 944 7883 TIDAL 3 4.366 1.170
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 6 of 6 Station ID: 9447883 PUBLICATION DATE: 06/15/2016 Name: GREENBANK, PUGET SOUND WA NOAA Chart: 18423 Latitude: 48° 6.3' N ( 48.10500) USGS Quad: FREELAND Longitude: 122° 34.2' W (-122.57000) 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.