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Bench Mark Sheet for 8557380, Lewes DE

Superseded Epoch

Large map location marker Station Location
Small red map location marker Published bench mark
Small blue map location marker Unpublished bench mark

Bench mark positions only appear on the map if their coordinates in the CO-OPS database are at the precision of degrees/minutes/seconds/and tenths of seconds. If the coordinates are less precise, the mark will not appear.

Printable version

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  7

                                                                                
Station ID: 8557380                         PUBLICATION DATE:  09/13/2017
Name:       LEWES, FT. MILES                                  
            DE
NOAA Chart: 12216                           Latitude:   38° 47.0' N (  38.78278)
USGS Quad:  CAPE HENLOPEN                   Longitude:  75°  7.1' W ( -75.11916)


To reach the tidal bench marks from the Post Office in Lewes, proceed SE on
Front Street for 0.2 km (0.1 mi), then 0.8 km (0.5 mi) NE on Savannah Road to
Henlopen Drive.  Continue on Henlopen Drive for 1.3 km (0.8 mi) to the Cape
May-Lewes Ferry Terminal.  The bench marks are within a 1.6 km (1 mi) radius of
the ferry terminal and the tide house is located on the west side of Ferry Slip
No. 2.


                         T I D A L   B E N C H   M A R K S


                 PRIMARY BENCH MARK STAMPING:  NO 20 1975
                         DESIGNATION:          855 7380 TIDAL 20

MONUMENTATION:           Tidal Station disk                    VM#:          390
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AJ8038
SETTING CLASSIFICATION:  Bollard foundation                    OPUS PID#: AJ8038
LATITUDE:   38° 46.9' N (  38.78233)          LONGITUDE:  75°  7.1' W ( -75.11867)


The primary bench mark is a disk set in the concrete foundation of a bollard
located east of ferry slip number 2, 3.44 m (11.3 ft) east of the east side of a
ramp, and 1.89 m (6.2 ft) north of the NW corner of a chain link fence on the
east side of the east loading ramp, 0.85 m (2.8 ft) east of the center of the
bollard.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  7

                                                                                
Station ID: 8557380                         PUBLICATION DATE:  09/13/2017
Name:       LEWES, FT. MILES                                  
            DE
NOAA Chart: 12216                           Latitude:   38° 47.0' N (  38.78278)
USGS Quad:  CAPE HENLOPEN                   Longitude:  75°  7.1' W ( -75.11916)


                         T I D A L   B E N C H   M A R K S


                         BENCH MARK STAMPING:  7380 B 1979
                         DESIGNATION:          855 7380 B

MONUMENTATION:           Tidal Station disk                    VM#:          395
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   38° 46.9' N (  38.78089)          LONGITUDE:  75°  7.0' W ( -75.11706)


The bench mark is a disk located south of the visitors parking area, 26.52 m
(87.0 ft) east of the centerline of the entrance road to the parking area, 24.41
m (80.1 ft) SE of the sign reading foot passager parking from east steel lag of
sign, 7.01 m (23.0 ft) south of the centerline of the drive to the east end of
the parking area, and 0.43 m (1.4 ft) north of the power pole stamped on the
west side CPT B288. The bench mark is 0.3 m (1 ft) below ground, crimped to the
top of a stainless steel rod driven 12.8 m (42 ft) to refusal, and encased in a
4 inch PVC pipe with concrete kickblock.



                         BENCH MARK STAMPING:  37 1947
                         DESIGNATION:          855 7380 TIDAL 37

MONUMENTATION:           Tidal Station disk                    VM#:          399
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  HU0087
SETTING CLASSIFICATION:  Flagpole foundation                   OPUS PID:        
LATITUDE:   38° 46.9' N (  38.78122)          LONGITUDE:  75°  7.2' W ( -75.11950)


The bench mark is set in the center of the SW concrete foundation, located at
the Harbor Pilots Association base, 31.1 m (102.0 ft) north of NE corner of the
pilots residence, 27.19 m (89.21 ft) NE of the ne corner of a concrete flag pole
foundation (flag pole no longer exists), 19.48 m (63.91 ft) east of a walkway
leading to the dock, and 8.69 m (28.51 ft) west of a chain link fence along the
east side of the base.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  7

                                                                                
Station ID: 8557380                         PUBLICATION DATE:  09/13/2017
Name:       LEWES, FT. MILES                                  
            DE
NOAA Chart: 12216                           Latitude:   38° 47.0' N (  38.78278)
USGS Quad:  CAPE HENLOPEN                   Longitude:  75°  7.1' W ( -75.11916)


                         T I D A L   B E N C H   M A R K S


                         BENCH MARK STAMPING:  7380 D 1986
                         DESIGNATION:          855 7380 D

MONUMENTATION:           Tidal Station disk                    VM#:          400
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   38° 46.9' N (  38.78225)          LONGITUDE:  75°  7.1' W ( -75.11756)


The bench mark is a disk located in the miniature golf course near the ferry
terminal concession stand, 21.34 m (70.0 ft) NE of the NE corner of the ferry
terminal building, 5.12 m (16.8 ft) south of the teak wood deck, 4.18 m (13.7
ft) east of the east edge of the concrete and brick patio surrounding the
restaurant, and 0.52 m (1.7 ft) south of a NOAA witness post. The bench mark is
0.3 m (1 ft) below ground, crimped to a stainless steel rod driven 14.0 m (46
ft) to refusal, and encased in a 6 inch PVC pipe with concrete kickblock.



                         BENCH MARK STAMPING:  7380 E 1986
                         DESIGNATION:          855 7380 E

MONUMENTATION:           Tidal Station disk                    VM#:          401
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   38° 46.9' N (  38.78092)          LONGITUDE:  75°  7.1' W ( -75.11828)


The bench mark is a disk located at the ferry terminal parking area, 29.63 (97.2
ft) east of the centerline of the exit gate, 29.17 m (95.7 ft) north of the
centerline of Henlopen Drive, 29.02 m (95.2 ft) SW of the SW corner of the
westernmost ticket booth, 0.67 m (2.2 ft) north of power pole number 24, and
0.67 m (2.2 ft) east of a witness post.  The bench mark is 0.15 m (0.5 ft) below
ground, crimped to a stainless steel rod driven 12.8 m (42 ft) to refusal, and
encased in a 6 inch PVC pipe with concrete kickblock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  7

                                                                                
Station ID: 8557380                         PUBLICATION DATE:  09/13/2017
Name:       LEWES, FT. MILES                                  
            DE
NOAA Chart: 12216                           Latitude:   38° 47.0' N (  38.78278)
USGS Quad:  CAPE HENLOPEN                   Longitude:  75°  7.1' W ( -75.11916)


                         T I D A L   B E N C H   M A R K S


                         BENCH MARK STAMPING:  GPS S-5A 1990
                         DESIGNATION:          GPS S 5 A

MONUMENTATION:           Horizontal Station disk               VM#:        13820
AGENCY:                  DEDHT                                 IDB PID#:  HU2679
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   38° 46.6' N (  38.77642)          LONGITUDE:  75°  7.8' W ( -75.12928)


The bench mark is a disk set in a 0.3 m x 0.3 m (1 ft x 1 ft) concrete monument,
located along the north side of U.S. Highway 9 between the bridge over the Lewes
and Rehoboth Canal and the turnoff to the Cape May - Lewes Ferry, 128.0 m (420
ft) east of the east end of the concrete curb on the bridge slope, 49.80 m
(163.4 ft) west of a road reflector post, 7.80 m (25.6 ft) north of the highway
centerline, 1.01 m (3.3 ft) north of a metal guardrail, and 0.3 m (1 ft) south
of a fiberglass witness post.



                         BENCH MARK STAMPING:  7380 F 1997
                         DESIGNATION:          855 7380 F

MONUMENTATION:           Flange-encased Rod                    VM#:        13821
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod in sleeve         OPUS PID:        
LATITUDE:   38° 46.8' N (  38.78019)          LONGITUDE:  75°  7.6' W ( -75.12592)


The bench mark is located along the north side of Henlopen Drive about 0.40 km
(0.25 mi) before the entrance to the ferry terminal, 48.01 m (157.5 ft) ESE of
the centerline of a paved road leading to the Pilots Point Condos, 13.80 m (45.3
ft) NNE of the centerline of Henlopen Drive, 8.25 m (27.1 ft) WNW of a steel
structure over the road, and 0.35 m (1.2 ft) SSW of a NOAA witness post. The
datum point is the top of a stainless steel rod driven 12.07 m (39.6 ft) to
refusal, in a grease filled sleeve extending to a depth of 1 m (3 ft), and
encased in a 5 inch logo cap.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  7

                                                                                
Station ID: 8557380                         PUBLICATION DATE:  09/13/2017
Name:       LEWES, FT. MILES                                  
            DE
NOAA Chart: 12216                           Latitude:   38° 47.0' N (  38.78278)
USGS Quad:  CAPE HENLOPEN                   Longitude:  75°  7.1' W ( -75.11916)


                         T I D A L   B E N C H   M A R K S


                         BENCH MARK STAMPING:  7380 G 1997
                         DESIGNATION:          855 7380 G

MONUMENTATION:           Flange-encased Rod                    VM#:        13822
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod in sleeve         OPUS PID:        
LATITUDE:   38° 46.8' N (  38.78019)          LONGITUDE:  75°  7.6' W ( -75.12592)


The bench mark is a disk located near the intersection of U.S. Highway 9 and
Henlopen Drive, 24.20 m (79.4 ft) west of the south leg of a green state highway
sign, 12.70 m (41.7 ft) NNE of the center median strip of Henlopen Drive, 10.40
m (34.1 ft) west of power pole number 14 with light, and 0.35 m (1.15 ft) SSW of
a NOAA witness post. The datum point is the top of a stainless steel rod driven
18.20 m (59.7 ft) to refusal, in a grease filled sleeve extending to a depth of
1 m (3.3 ft), and encased in a 5 inch logo cap. Note-The sleeve depth does not
meet the specifications for a Class A rod mark.



                         BENCH MARK STAMPING:  7380 H 2003
                         DESIGNATION:          855 7380 H

MONUMENTATION:           Tidal Station disk                    VM#:        17205
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete foundation                   OPUS PID:        
LATITUDE:   38° 47.0' N (  38.78289)          LONGITUDE:  75°  7.2' W ( -75.11919)


The bench mark is a disk set in the concrete foundation for a yellow bollard
located on the north side of the NOAA tide station between bumper 37 and bumper
36, 10.58 m (34.7 ft) east of the west side of slip 1, 5.43 m (17.8 ft) north of
the north side of the tide shelter box, and 1.65 m (5.4 ft) west of the east
side of the slip.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of  7

                                                                                
Station ID: 8557380                         PUBLICATION DATE:  09/13/2017
Name:       LEWES, FT. MILES                                  
            DE
NOAA Chart: 12216                           Latitude:   38° 47.0' N (  38.78278)
USGS Quad:  CAPE HENLOPEN                   Longitude:  75°  7.1' W ( -75.11916)


                            T I D A L   D A T U M S 


Tidal datums at LEWES, FT. MILES based on:

     LENGTH OF SERIES:      19 YEARS
     TIME PERIOD:           January 1983 - December 2001
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:   


Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:

     HIGHEST OBSERVED WATER LEVEL (01/23/2016)         =  2.821
     MEAN HIGHER HIGH WATER                     MHHW   =  1.418
     MEAN HIGH WATER                            MHW    =  1.290
     North American Vertical Datum              NAVD88 =  0.801
     MEAN SEA LEVEL                             MSL    =  0.680
     MEAN TIDE LEVEL                            MTL    =  0.669
     MEAN LOW WATER                             MLW    =  0.048
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (01/10/1978)         = -1.284

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     NO 20 1975                                  3.142    1.852
     7380 B 1979                                 2.566    1.276
     37 1947                                     3.254    1.964
     7380 D 1986                                 2.904    1.614
     7380 E 1986                                 1.957    0.667
     GPS S-5A 1990                               3.194    1.904
     7380 F 1997                                 1.887    0.597
     7380 G 1997                                 2.019    0.729
     7380 H 2003                                 3.106    1.816


                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  7 of  7

                                                                                
Station ID: 8557380                         PUBLICATION DATE:  09/13/2017
Name:       LEWES, FT. MILES                                  
            DE
NOAA Chart: 12216                           Latitude:   38° 47.0' N (  38.78278)
USGS Quad:  CAPE HENLOPEN                   Longitude:  75°  7.1' W ( -75.11916)


                             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.

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Products available at 8557380 Lewes, DE

Revised: 10/15/2013
NOAA / National Ocean Service
Web site owner: Center for Operational Oceanographic Products and Services