U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Datums Page Page 1 of 6 Station ID: 8638491 PUBLICATION DATE: 01/17/2013 Name: VEPCO PLANT, CHESTER, JAMES RIVER VA NOAA Chart: 12252 Latitude: 37° 23.0' N ( 37.38330) USGS Quad: DREWRYS BLUFF Longitude: 77° 22.7' W ( -77.37830) To reach from the intersection of I-95 and VA Route 10, drive east on VA Route 10 for 0.5 km (0.3 mi) turn left on Old Stage Road, then drive north on Old Stage Road for 3.2 km (2.0 mi) and turn right on to Coxendale Road, continue east on Coxendale Road 1.6 km (1.0 mi) toward the boat ramp. The tide station is located on an elevated concrete pad, accessible by boat only. T I D A L B E N C H M A R K S PRIMARY BENCH MARK STAMPING: NO 1 1971 DESIGNATION: 863 8491 NO 1 MONUMENTATION: Bench Mark disk VM#: 20491 AGENCY: US Coast and Geodetic Survey (USC&GS) IDB PID#: SETTING CLASSIFICATION: Concrete pile cap OPUS PID: LATITUDE: 37° 23.0' N ( 37.38269) LONGITUDE: 77° 22.7' W ( -77.37825) The primary bench mark is a disk set on top of a concrete pile cap near the north end of the abandoned oil dock located 47.30 m (155.2 ft) WNW of the mooring bollard at the south end of the abandoned oil dock, 28.30 m (92.8 ft) NNW of the SW end of a fence on the shore for the old gangway, 21.10 m (69.2 ft) NE of the NE end of the security fence on shore, 10.30 m (33.8 ft) SW of the mooring bollard at the north end of an abandoned oil dock, and 0.55 m (1.8 ft) NE of the SW corner of a concrete pile cap.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 2 of 6 Station ID: 8638491 PUBLICATION DATE: 01/17/2013 Name: VEPCO PLANT, CHESTER, JAMES RIVER VA NOAA Chart: 12252 Latitude: 37° 23.0' N ( 37.38330) USGS Quad: DREWRYS BLUFF Longitude: 77° 22.7' W ( -77.37830) T I D A L B E N C H M A R K S BENCH MARK STAMPING: 8491 A 2011 DESIGNATION: 863 8491 A MONUMENTATION: Survey disk VM#: 20489 AGENCY: U.S. Army Corp Of Engineers (USACE) IDB PID#: SETTING CLASSIFICATION: Lamp pole foundation OPUS PID: LATITUDE: 37° 22.9' N ( 37.38206) LONGITUDE: 77° 22.7' W ( -77.37917) The bench mark is a disk set in the concrete base of lamp pole number LP13, 48.70 m (159.8 ft) NW of a street light pole number LP19, 48.50 m (159.1 ft) NE of a street light pole number LP17, 44.30 m (145.3 ft) SW of a power pole with wooden buttress VF83 and 35.30 m (115.8 ft) WSW of the NW end of the chain link fence at Dominion Power parking lot. BENCH MARK STAMPING: ELIJAH 1978 DESIGNATION: 863 8491 ELIJAH MONUMENTATION: Survey disk VM#: 20490 AGENCY: U.S. Army Corp Of Engineers (USACE) IDB PID#: SETTING CLASSIFICATION: CONCRETE AND STEEL MOORING POST OPUS PID: LATITUDE: 37° 22.9' N ( 37.38208) LONGITUDE: 77° 22.6' W ( -77.37700) The bench mark is a disk set in the top of a concrete and steel mooring post located 45.00 m (147.6 ft) SSE of a steel pile mooring dolphin in the James River, 41.70 m (136.8 ft) NW of the NW corner at the bottom of the steel steps from the parking lot, 40.50 m (132.9 ft) SE of bench mark Sprinkle, 31.90 m (104.7 ft) NNE of the pole with lights at the parking lot, and 7.71 m (25.3 ft) WNW of pole with lights at the boat ramp.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 3 of 6 Station ID: 8638491 PUBLICATION DATE: 01/17/2013 Name: VEPCO PLANT, CHESTER, JAMES RIVER VA NOAA Chart: 12252 Latitude: 37° 23.0' N ( 37.38330) USGS Quad: DREWRYS BLUFF Longitude: 77° 22.7' W ( -77.37830) T I D A L B E N C H M A R K S BENCH MARK STAMPING: NO 2 1971 DESIGNATION: 863 8491 NO 2 MONUMENTATION: Bench Mark disk VM#: 20492 AGENCY: US Coast and Geodetic Survey (USC&GS) IDB PID#: SETTING CLASSIFICATION: Concrete base OPUS PID: LATITUDE: 37° 23.0' N ( 37.38258) LONGITUDE: 77° 22.8' W ( -77.38006) The bench mark is a disk set on the top of the concrete base for the NE leg of the large electric transmission tower closest to the west bank of the James River located 45.40 m (148.9 ft) NNE of the NW corner of the guard shack, 32.80 m (107.6 ft) WSW of a power line pole #BF45, 32.40 m (99.7 ft) NW of a street light pole #LP09, 26.20 m (86.0 ft) SSE of a power line pole with transformer and meter and switches. BENCH MARK STAMPING: SPRINKLE 1978 DESIGNATION: 863 8491 SPRINKLE MONUMENTATION: Survey disk VM#: 20493 AGENCY: U.S. Army Corp Of Engineers (USACE) IDB PID#: SETTING CLASSIFICATION: Concrete and steel mooring post OPUS PID: LATITUDE: 37° 22.9' N ( 37.38217) LONGITUDE: 77° 22.6' W ( -77.37742) The bench mark is set in the top of a concrete and steel mooring posted located 50.90 m (167.0 ft) SE of a mooring bollard on a concrete cap at the end of an abandoned oil dock on the James River, 40.50 m (132.9 ft) NW of USACE bench mark Elijah, 29.80 m (97.8 ft) east of a light pole TF-19, 27.20 m (89.2 ft) ENE of most southernly post of park entrance sign and 11.80 m (38.7 ft) NE of the center paved road to the boat ramp.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 4 of 6 Station ID: 8638491 PUBLICATION DATE: 01/17/2013 Name: VEPCO PLANT, CHESTER, JAMES RIVER VA NOAA Chart: 12252 Latitude: 37° 23.0' N ( 37.38330) USGS Quad: DREWRYS BLUFF Longitude: 77° 22.7' W ( -77.37830) T I D A L B E N C H M A R K S BENCH MARK STAMPING: WALTER 2009 DESIGNATION: WALTER MONUMENTATION: Survey disk VM#: 20494 AGENCY: U.S. Army Corp Of Engineers (USACE) IDB PID#: SETTING CLASSIFICATION: Concrete monument OPUS PID: LATITUDE: 37° 22.9' N ( 37.38214) LONGITUDE: 77° 22.7' W ( -77.37850) The bench mark is a disk set in concrete monument located 42.40 m (139.1 ft) SE of a power pole with wooden buttress #VF83, 39.50 m (129.6 ft) west of a power pole #WF42, 26.30 m (86.3 ft) NW of Dominion Power sign, 22.90 m (75.1 ft) ENE of the NW end of a chain link fence at Dominion Power parking lot, and 21.70 m (71.2 ft) SSE of the SW end of the security warning sign.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 5 of 6 Station ID: 8638491 PUBLICATION DATE: 01/17/2013 Name: VEPCO PLANT, CHESTER, JAMES RIVER VA NOAA Chart: 12252 Latitude: 37° 23.0' N ( 37.38330) USGS Quad: DREWRYS BLUFF Longitude: 77° 22.7' W ( -77.37830) T I D A L D A T U M S Tidal datums at VEPCO PLANT, CHESTER, JAMES RIVER based on: LENGTH OF SERIES: 3 MONTHS TIME PERIOD: February 2012 - April 2012 TIDAL EPOCH: 1983-2001 CONTROL TIDE STATION: 8638610 SEWELLS POINT, HAMPTON ROADS Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS: MEAN HIGHER HIGH WATER MHHW = 0.990 MEAN HIGH WATER MHW = 0.915 MEAN SEA LEVEL MSL = 0.502 MEAN TIDE LEVEL MTL = 0.476 MEAN LOW WATER MLW = 0.037 MEAN LOWER LOW WATER MLLW = 0.000 North American Vertical Datum (NAVD88) Bench Mark Elevation Information In METERS above: Stamping or Designation MLLW MHW NO 1 1971 3.877 2.962 8491 A 2011 8.986 8.071 ELIJAH 1978 5.019 4.104 NO 2 1971 10.316 9.401 SPRINKLE 1978 5.002 4.087 WALTER 2009 7.622 6.707
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 6 of 6 Station ID: 8638491 PUBLICATION DATE: 01/17/2013 Name: VEPCO PLANT, CHESTER, JAMES RIVER VA NOAA Chart: 12252 Latitude: 37° 23.0' N ( 37.38330) USGS Quad: DREWRYS BLUFF Longitude: 77° 22.7' W ( -77.37830) 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.