U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
Station ID: 8720406 PUBLICATION DATE: 12/04/2009
Name: DOCTORS LAKE, PEORIA POINT
FL
NOAA Chart: 11495 Latitude: 30° 7.2' N ( 30.12000)
USGS Quad: MIDDLEBURG Longitude: 81° 45.5' W ( -81.75830)
To reach the tidal bench marks from the intersection of US Highway 17 and State
Highway 224 in Orange Park, proceed 0.8 km (0.5 mi) west along State Highway 224
to Doctors Lake Road, proceed 7.1 km (4.4 mi) SW on Doctors Lake Road to Cedar
Road, then 0.2 km (0.1 mi) on Cedar Road, then 0.2 km (0.1 mi) on Cedar Road to
Holly Road, then continue 0.3 km (0.2 mi) east on Holly Road to Magnolia Road,
then south on Magnolia Road to 4221 Magnolia Road. The bench marks are located
along Magnolia and Holly Roads. The tide gauge and staff were located on the
property at 4221 Magnolia Road.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 0406 C 1978
DESIGNATION: 872 0406 C TIDAL
MONUMENTATION: Tidal Station disk VM#: 10724
AGENCY: National Ocean Survey (NOS) IDB PID#: BC1436
SETTING CLASSIFICATION: Copper-clad steel rod OPUS PID:
LATITUDE: 30° 7.3' N ( 30.12111) LONGITUDE: 81° 45.7' W ( -81.76083)
The primary bench mark is a disk located in the triangular island at the
junction of Holly Road and Magnolia Road, 15.18 m (49.8 ft) SW of a wooden power
pole Number 4107, 14.02 m (46.0 ft) south of a driveway, 3.84 m (12.6 ft) south
of the projection of the south edge of the tangent portion of Holly Road, 6.86 m
(22.5 ft) west of the centerline of magnolia road and 0.21 m (0.7 ft) SW of a
carsonite witness post. The bench mark is set flush with the ground, crimped to
the top of a copper-clad steel rod driven 9.75 m (32.0 ft) to refusal, and
encased in a PVC pipe with concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
Station ID: 8720406 PUBLICATION DATE: 12/04/2009
Name: DOCTORS LAKE, PEORIA POINT
FL
NOAA Chart: 11495 Latitude: 30° 7.2' N ( 30.12000)
USGS Quad: MIDDLEBURG Longitude: 81° 45.5' W ( -81.75830)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 0406 A 1978
DESIGNATION: 872 0406 A TIDAL
MONUMENTATION: Tidal Station disk VM#: 10722
AGENCY: National Ocean Survey (NOS) IDB PID#: BC1437
SETTING CLASSIFICATION: Concrete monument OPUS PID:
LATITUDE: 30° 7.2' N ( 30.11944) LONGITUDE: 81° 45.6' W ( -81.75972)
The bench mark is a disk set in the top of a concrete monument flush with the
ground and level with the road, located on the east side of Magnolia Road near
the south property line of the residence at 4221 Magnolia Road, 6.40 m (21.0 ft)
east of the approximate centerline of Magnolia Drive, 2.13 m (7.0 ft) north of
twin oak tree; 0.40 m (1.3 ft) south of a wooden power pole No. 4223, and 0.30 m
(1.0 ft) SW of a metal witness post.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
Station ID: 8720406 PUBLICATION DATE: 12/04/2009
Name: DOCTORS LAKE, PEORIA POINT
FL
NOAA Chart: 11495 Latitude: 30° 7.2' N ( 30.12000)
USGS Quad: MIDDLEBURG Longitude: 81° 45.5' W ( -81.75830)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 0406 D 1978
DESIGNATION: 872 0406 D TIDAL
MONUMENTATION: Tidal Station disk VM#: 10725
AGENCY: National Ocean Survey (NOS) IDB PID#: BC1435
SETTING CLASSIFICATION: Copper-clad steel rod OPUS PID:
LATITUDE: 30° 7.4' N ( 30.12278) LONGITUDE: 81° 45.8' W ( -81.76361)
The bench mark is a disk located 34.14 m (112.0 ft) SE of the intersection of
224A (Doctors Lake Drive) and Bay Road, 20.12 m (66.0 ft) SW of the approximate
centerline of Bay Road, 16.46 m (54.0 ft) NW of the NW corner of house number
4055 Cedar Road, 12.95 m (42.5 ft) SE of a large pine tree, 11.89 m (39.0 ft)
NNE of the south end of the median island in Cedar Road, 6.40 m (21.0 ft) SE of
the west edge of the southbound pavement of Cedar Road, 5.70 m (18.7 ft) NNE of
a small oak tree at the south end of the median, 5.00 m (16.4 ft) NW of the east
edge of the northbound pavement of Cedar Road and 24.38 cm (0.8 ft) NE of a
carsonite witness post, and 18.29 cm (0.6 ft) above the level of cedar road.
The bench mark is recessed 9.14 cm (0.3 ft) below the level of the ground,
crimped to the top of a copper-clad steel rod driven 9.75 m (32.0 ft) to
refusal, and encased in a 5-inch PVC pipe with concrete kickblock.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
Station ID: 8720406 PUBLICATION DATE: 12/04/2009
Name: DOCTORS LAKE, PEORIA POINT
FL
NOAA Chart: 11495 Latitude: 30° 7.2' N ( 30.12000)
USGS Quad: MIDDLEBURG Longitude: 81° 45.5' W ( -81.75830)
T I D A L D A T U M S
Tidal datums at DOCTORS LAKE, PEORIA POINT based on:
LENGTH OF SERIES: 5 MONTHS
TIME PERIOD: June 1978 - October 1978
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8720496 GREEN COVE SPRINGS, ST. JOHNS R.
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 0.278
MEAN HIGH WATER MHW = 0.257
MEAN TIDE LEVEL MTL = 0.136
MEAN SEA LEVEL MSL = 0.130
North American Vertical Datum NAVD88 = 0.117
MEAN LOW WATER MLW = 0.014
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
0406 C 1978 3.878 3.621
0406 A 1978 3.084 2.827
0406 D 1978 6.638 6.381
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
Station ID: 8720406 PUBLICATION DATE: 12/04/2009
Name: DOCTORS LAKE, PEORIA POINT
FL
NOAA Chart: 11495 Latitude: 30° 7.2' N ( 30.12000)
USGS Quad: MIDDLEBURG Longitude: 81° 45.5' W ( -81.75830)
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.