U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Datums Page Page 1 of 5 Station ID: 9751309 PUBLICATION DATE: 11/18/2011 Name: LEINSTER POINT, LEINSTER BAY, ST. JOHN'S VI NOAA Chart: 25641 Latitude: 18° 22.1' N ( 18.36761) USGS Quad: WESTERN ST JOHN Longitude: 64° 43.2' W ( -64.72072) To reach the tidal bench marks from the National Park Service Visitor Center at St John, Cruz Bay, travel east from the Visitor Center for 200 m (0.1 mi) to North Shore Road Route 20 and turn left, then take another immediate left to stay on Route 20 at the NPS Maintenance Area signs, and continue on Route 20 as it winds eastward for 9.0 km (5.6 mi) towards Annaberg to a fork in the road where the east bound and west bound lanes split, continue east on Route 20 for another 1.1 km (0.7 mi) to a stop sign, turn right towards Annaberg and travel east 400 m (0.2 mi) to the Annaberg Plantation parking lot, continue east on foot along the trail that starts on the beach just east of the parking lot for 1.24 km (0.77 mi) as it follows the shoreline around Leinster Bay and Watermelon Bay to a tidal stream at the SE end of the sandy beach on Watermelon Bay, cross the stream and continue NE on the trail in the woods along the beach for 0.13 km (0.1 mi) to a fork in the trail, take the less traveled trail to the left continuing along the shoreline to the NW for 0.31 km (0.2 mi) to where the trail dead ends into the beach, follow the shoreline north for 0.22 km (0.13 mi) to the end of Leinster Point. The bench marks are in the bedrock on either side of the point. T I D A L B E N C H M A R K S PRIMARY BENCH MARK STAMPING: 1309 A 2010 DESIGNATION: 975 1309 A MONUMENTATION: Tidal Station disk VM#: 19777 AGENCY: National Ocean Service (NOS) IDB PID#: SETTING CLASSIFICATION: Bedrock outcrop. OPUS PID#: BBCH99 LATITUDE: 18° 22.1' N ( 18.36764) LONGITUDE: 64° 43.2' W ( -64.72033) The primary bench mark is set flush in bedrock on the east side of Leinster Point near the north end of a sand and gravel beach, 19.05 m (62.5 ft) south of bench mark 975 1309 B, 7.45 m (24.4 ft) north of the north end of the beach, 4.54 m (14.9 ft) east of a prominent triangular shattered bedrock cliff face extending out of the grass and trees above the north end of the beach, and 0.99 m (3.25 ft) SE of vegetation line.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 2 of 5 Station ID: 9751309 PUBLICATION DATE: 11/18/2011 Name: LEINSTER POINT, LEINSTER BAY, ST. JOHN'S VI NOAA Chart: 25641 Latitude: 18° 22.1' N ( 18.36761) USGS Quad: WESTERN ST JOHN Longitude: 64° 43.2' W ( -64.72072) T I D A L B E N C H M A R K S BENCH MARK STAMPING: 1309 B 2010 DESIGNATION: 975 1309 B MONUMENTATION: Tidal Station disk VM#: 19778 AGENCY: National Ocean Service (NOS) IDB PID#: SETTING CLASSIFICATION: Bedrock outcrop. OPUS PID: LATITUDE: 18° 22.1' N ( 18.36781) LONGITUDE: 64° 43.2' W ( -64.72028) The bench mark is set flush in an elevated section of bedrock extending to the NE on the east side of the end of Leinster Point, 60.21 m (197.5 ft) NE of bench mark 975 1309 C measured around the end of the point, 25.61 m (84.0 ft) north of the north end of the beach on the east side of Leinster Point, 4.35 m (14.25 ft) NE of a 6 m (20 ft) tall cliff face on the east side of Leinster Point, and 1.59 m (5.2 ft) above the surrounding bedrock and gravel beach. BENCH MARK STAMPING: 1309 C 2010 DESIGNATION: 975 1309 C MONUMENTATION: Tidal Station disk VM#: 19779 AGENCY: National Ocean Service (NOS) IDB PID#: SETTING CLASSIFICATION: Bedrock outcrop. OPUS PID: LATITUDE: 18° 22.1' N ( 18.36758) LONGITUDE: 64° 43.2' W ( -64.72072) The bench mark is set flush in an outcropping of striped bedrock on the west side of the end of Leinster Point, 60.21 m (197.5 ft) SW of bench mark 975 1309 B measured around the end of the point, 16.95 m (55.6 ft) NE of bench mark 975 1309 D measured on a curve along the shore, 8.33 m (27.3 ft) south of a large 1.0 m x 2.6 m x 1.4 m (3.2 ft x 8.5 ft x 4.6 ft) angular boulder offshore of the point, 0.84 m (2.75 ft) NW of a cliff face of the NW side of the end of the point, and 0.91 m (2.9 ft) above the surrounding stone beach.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 3 of 5 Station ID: 9751309 PUBLICATION DATE: 11/18/2011 Name: LEINSTER POINT, LEINSTER BAY, ST. JOHN'S VI NOAA Chart: 25641 Latitude: 18° 22.1' N ( 18.36761) USGS Quad: WESTERN ST JOHN Longitude: 64° 43.2' W ( -64.72072) T I D A L B E N C H M A R K S BENCH MARK STAMPING: 1309 D 2010 DESIGNATION: 975 1309 D MONUMENTATION: Tidal Station disk VM#: 19780 AGENCY: National Ocean Service (NOS) IDB PID#: SETTING CLASSIFICATION: Bedrock outcrop. OPUS PID: LATITUDE: 18° 22.0' N ( 18.36747) LONGITUDE: 64° 43.2' W ( -64.72075) The bench mark is set flush in small ledge in a bedrock wall on the west side of Leinster Point, 92.32 m (302.8 ft) north of bench mark 975 1309 E, 16.95 m (55.6 ft) SW of bench mark 975 1309 C measured on a curve along the shore, 11.57 m (37.9 ft) north of the north end of the gravel beach that runs along the west side of the point, 2.91 m (9.5 ft) north of the most western point of the dark bedrock outcrop, and 1.22 m (4.0 ft) above the level of the surrounding stone beach. BENCH MARK STAMPING: 1309 E 2010 DESIGNATION: 975 1309 E MONUMENTATION: Tidal Station disk VM#: 19781 AGENCY: National Ocean Service (NOS) IDB PID#: SETTING CLASSIFICATION: Bedrock outcrop. OPUS PID: LATITUDE: 18° 23.0' N ( 18.38331) LONGITUDE: 64° 43.2' W ( -64.72064) The bench mark is set flush in a low bedrock outcrop at the south end of the gravel beach on the west side of Leinster Point, 92.32 m (302.8 ft) south of bench mark 975 1309 D, 22.86 m (74.9 ft) south of the only other bedrock outcrop visible along this beach before nearing the end of the point, 1.67 m (5.4 ft) south of the south end of the beach. 1.26 m (4.1 ft) west of the tree line, and 0.46 m (1.5 ft) above the level of the beach.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 4 of 5 Station ID: 9751309 PUBLICATION DATE: 11/18/2011 Name: LEINSTER POINT, LEINSTER BAY, ST. JOHN'S VI NOAA Chart: 25641 Latitude: 18° 22.1' N ( 18.36761) USGS Quad: WESTERN ST JOHN Longitude: 64° 43.2' W ( -64.72072) T I D A L D A T U M S Tidal datums at LEINSTER POINT, LEINSTER BAY, ST. JOHN'S based on: LENGTH OF SERIES: 4 MONTHS TIME PERIOD: December 2010 - March 2011 TIDAL EPOCH: 1983-2001 CONTROL TIDE STATION: 9755371 SAN JUAN, LA PUNTILLA, SAN JUAN BAY Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS: MEAN HIGHER HIGH WATER MHHW = 0.342 MEAN HIGH WATER MHW = 0.274 MEAN SEA LEVEL MSL = 0.159 MEAN TIDE LEVEL MTL = 0.156 MEAN LOW WATER MLW = 0.037 MEAN LOWER LOW WATER MLLW = 0.000 Bench Mark Elevation Information In METERS above: Stamping or Designation MLLW MHW 1309 A 2010 1.428 1.154 1309 B 2010 1.618 1.344 1309 C 2010 1.442 1.168 1309 D 2010 1.822 1.548 1309 E 2010 1.273 0.999
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 5 of 5 Station ID: 9751309 PUBLICATION DATE: 11/18/2011 Name: LEINSTER POINT, LEINSTER BAY, ST. JOHN'S VI NOAA Chart: 25641 Latitude: 18° 22.1' N ( 18.36761) USGS Quad: WESTERN ST JOHN Longitude: 64° 43.2' W ( -64.72072) 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 any other fixed island datum. This tide station location has a defined island datum (VIVD09). Island datums are specific fixed geodetic datums whose elevation relationship to local MSL and other tidal datums may not be consistent from one location to another. Virgin Islands Vertical Datum of 2009 (VIVD09) is a fixed datum derived from a simultaneous, least squares, minimum constraint adjustment of leveling observations. Local mean sea level relative to the 1983-2001 National Tidal Datum Epoch observed at tide stations 9751401 located at Lime Tree Bay, St. Croix, 9751381 located at Lameshur Bay, St. John, and 9751639 located at Charlotte Amalie, St Thomas was held fixed as the single initial constraint. VIVD09 replaces all previous height system as the national standard geodetic reference for heights in the Virgin Islands. Bench mark elevations relative to VIVD09 are available from NGS through the World Wide Web at National Geodetic Survey. 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 VIVD09 elevation is shown on the Elevations of Tidal Datums Table Referred to MLLW only when two or more of the bench marks listed have VIVD09 elevations. The VIVD09 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, VIVD09 bench mark elevations computed indirectly from the tidal datums elevation table may differ slightly from VIVD09 elevations listed for each bench mark in the NGS database.