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Bench Mark Sheet for 8551910, Reedy Point 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Superseded Epoch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Small blue map location marker Unpublished bench mark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  8

                                                                                
Station ID: 8551910                         PUBLICATION DATE:  09/27/2011
Name:       REEDY POINT, C&D CANAL                        
            DE
NOAA Chart: 12277                           Latitude:   39° 33.5' N (  39.55831)
USGS Quad:  DELAWARE CITY                   Longitude:  75° 34.4' W ( -75.57331)


To reach the tidal bench marks from the intersection of Clinton Street and State
Highway 9 in Delaware City, proceed 3.5 km (2.2 mi) south on Highway 9 over the
Reedy Point bridge to South Reedy Point Road, turn right and continue 1.3 km
(0.8 mi) to a gravel road that parallels the Chesapeake and Delaware Canal, then
turn right and proceed 0.8 km (0.5 mi) to the Corps of Engineers T-pier.  The
bench marks are along South Reedy Point Road, the gravel road, and State Highway
9.  The tide gauge and staff are on the pier, east of the bridge and on the
south side of the canal.


                         T I D A L   B E N C H   M A R K S
                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  8

                                                                                
Station ID: 8551910                         PUBLICATION DATE:  09/27/2011
Name:       REEDY POINT, C&D CANAL                        
            DE
NOAA Chart: 12277                           Latitude:   39° 33.5' N (  39.55831)
USGS Quad:  DELAWARE CITY                   Longitude:  75° 34.4' W ( -75.57331)


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


                 PRIMARY BENCH MARK STAMPING:  R 41 1979
                         DESIGNATION:          R 41

MONUMENTATION:           Bench Mark disk                       VM#:          383
AGENCY:                  National Geodetic Survey (NGS)        IDB PID#:  JU2187
SETTING CLASSIFICATION:  Bridge pier foundation                OPUS PID:        
LATITUDE:   39° 33.4' N (  39.55672)          LONGITUDE:  75° 34.9' W ( -75.58175)


The primary bench mark is a disk set in the concrete foundation of the most
easterly of the two concrete piers of the first row of bridge piers south of the
south bank of the Chesapeake and Delaware canal, 16.70 m (54.79 ft) east of a
gravel service road that parallels the bridge, 0.3 m (1.0 ft) south of the north
face of the pier, and 0.02 m (0.07 ft) west of the west edge of the pier, 0.3 m
(1.0 ft) below ground.



                         BENCH MARK STAMPING:  1910 B 1979
                         DESIGNATION:          855 1910 B TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:          376
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  JU2189
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   39° 33.4' N (  39.55669)          LONGITUDE:  75° 34.4' W ( -75.57331)


The bench mark is a disk located west of the pier on the south side of the dirt
road along the canal bank, 129.0 m (423.2 ft) WSW of the SW corner of the pier,
12.07 m (39.6 ft) south of utility pole number 75 with light, and 6.40 m (21.0
ft) south of the center of the dirt road.  The bench mark is set 15 cm (0.5 ft)
above ground, crimped to the top of a stainless steel rod driven 9.8 m (32 ft)
to refusal, and encased in a 4 inch PVC pipe with concrete kickblock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  8

                                                                                
Station ID: 8551910                         PUBLICATION DATE:  09/27/2011
Name:       REEDY POINT, C&D CANAL                        
            DE
NOAA Chart: 12277                           Latitude:   39° 33.5' N (  39.55831)
USGS Quad:  DELAWARE CITY                   Longitude:  75° 34.4' W ( -75.57331)


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


                         BENCH MARK STAMPING:  1910 C 1979
                         DESIGNATION:          855 1910 C TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:          381
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  JU2188
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   39° 33.4' N (  39.55670)          LONGITUDE:  75° 34.6' W ( -75.57670)


The bench mark is a disk located on the south side of the dirt road along the
canal bank, 0.3 km (0.2 mi) west of the pier, 13.72 m (45.0 ft) south of utility
pole number 85 with light, 6.71 m (22.0 ft) south of the centerline of the dirt
road, and 0.61 m (2.0 ft) north of a NOS witness post. The bench mark is set 15
cm (0.5 ft) above ground, crimped to the top of a stainless steel rod driven 9.1
m (30 ft) to refusal, and encased in a 4 inch PVC pipe with concrete kickblock.



                         BENCH MARK STAMPING:  1910 G 1982
                         DESIGNATION:          855 1910 G

MONUMENTATION:           Tidal Station disk                    VM#:          382
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AJ6314
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID#: AJ6314
LATITUDE:   39° 33.5' N (  39.55844)          LONGITUDE:  75° 34.3' W ( -75.57219)


The bench mark is a disk set on the south side of the dirt road along the canal
bank, on the extended centerline of the wood pier located on the bank, 26.06 m
(85.50 ft) SW of a utility pole with light on the east side of the pier, 15.24 m
(50.0 ft) south of the SW end of the pier, and 7.01 m (23.0 ft) south of the
centerline of the dirt road. The bench mark is set 0.3 m (1 ft) below ground,
crimped to the top of a stainless steel rod driven 8.8 m (28.9 ft) with 6 in (15
cm) water pipe surround the mark, and 0.6 m (2.0 ft) below ground.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  8

                                                                                
Station ID: 8551910                         PUBLICATION DATE:  09/27/2011
Name:       REEDY POINT, C&D CANAL                        
            DE
NOAA Chart: 12277                           Latitude:   39° 33.5' N (  39.55831)
USGS Quad:  DELAWARE CITY                   Longitude:  75° 34.4' W ( -75.57331)


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


                         BENCH MARK STAMPING:  RP 3 1975
                         DESIGNATION:          855 1910 TIDAL RP 3

MONUMENTATION:           Tidal Station disk                    VM#:          385
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  JU2186
SETTING CLASSIFICATION:  Concrete culvert head wall            OPUS PID:        
LATITUDE:   39° 33.4' N (  39.55670)          LONGITUDE:  75° 34.9' W ( -75.58170)


The bench mark is a disk set in a concrete culvert headwall along the east side
of South Reedy Point Road, 147.0 m (482.3 ft) south of the canal, 50.11 m (164.4
ft) west of bridge Pier R38W, and 5.49 m (18.0 ft) east of the centerline of the
road.    The bench mark is a disk set in a concrete culvert headwall along the
east side of south reedy point road, 147 m (482.3 ft) south of the canal, 50.11
m (164.40 ft) west of bridge pier r38w, and 5.49 m (18.01 ft) east of the
centerline of the road.



                         BENCH MARK STAMPING:  RP 5 1975
                         DESIGNATION:          855 1910 TIDAL RP 5

MONUMENTATION:           Tidal Station disk                    VM#:          386
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  JU2185
SETTING CLASSIFICATION:  Concrete culvert head wall            OPUS PID:        
LATITUDE:   39° 33.1' N (  39.55170)          LONGITUDE:  75° 34.8' W ( -75.58000)


The bench mark is a disk set in a concrete culvert headwall along the west side
of South Reedy Point Road, 23.01 m (75.5 ft) NW of bridge pier R53W, 20.42 m
(67.0 ft) SW of bridge pier R52W, 6.80 m (22.3 ft) SE of utility pole number
DP&L 27, and 6.71 m (22.0 ft) west of the road centerline.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  8

                                                                                
Station ID: 8551910                         PUBLICATION DATE:  09/27/2011
Name:       REEDY POINT, C&D CANAL                        
            DE
NOAA Chart: 12277                           Latitude:   39° 33.5' N (  39.55831)
USGS Quad:  DELAWARE CITY                   Longitude:  75° 34.4' W ( -75.57331)


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


                         BENCH MARK STAMPING:  R 72 W
                         DESIGNATION:          855 1910 R 72 W

MONUMENTATION:           Survey disk                           VM#:        12414
AGENCY:                  US Army Corps of Engineers (USE)      IDB PID#:        
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   39° 32.8' N (  39.54619)          LONGITUDE:  75° 34.8' W ( -75.57992)


The bench mark is a disk set in a concrete monument located on the west side of
U.S. Highway 9 near the south end of the bridge leading over the canal, 121.3 m
(398.0 ft) NE of the junction of Route 9 and South Reedy Point Road, 59.62 m
(195.60 ft) south of the south end of the bridge, 7.19 m (23.59 ft) SW of the
centerline of Route 9, and 0.21 m (0.7 ft) west of the curb, and 0.7 m (2.3 ft)
above the road surface.



                         BENCH MARK STAMPING:  1910 H 1997
                         DESIGNATION:          855 1910 H

MONUMENTATION:           Flange-encased Rod                    VM#:        13758
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod in sleeve         OPUS PID:        
LATITUDE:   39° 33.3' N (  39.55444)          LONGITUDE:  75° 34.9' W ( -75.58164)


The bench mark is a flange encased rod located on the east side of South Reedy
Point Road, 0.3 km (0.2 mi) from the intersection of Dutch Neck Road, 65.20 m
(213.9 ft) south of the stop sign on the east side of the road, 4.50 m (14.76
ft) east of the road centerline, and 2.80 m (9.2 ft) west of a NOS witness post,
2.10 m (6.9 ft) east of the east edge of the road.  The datum point is the top
of a stainless steel rod driven 17.4 m (57.1 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.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of  8

                                                                                
Station ID: 8551910                         PUBLICATION DATE:  09/27/2011
Name:       REEDY POINT, C&D CANAL                        
            DE
NOAA Chart: 12277                           Latitude:   39° 33.5' N (  39.55831)
USGS Quad:  DELAWARE CITY                   Longitude:  75° 34.4' W ( -75.57331)


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


                         BENCH MARK STAMPING:  1910 J 1997
                         DESIGNATION:          855 1910 J

MONUMENTATION:           Flange-encased Rod                    VM#:        13759
AGENCY:                  National Ocean Service (NOS)          IDB PID#:  AJ6315
SETTING CLASSIFICATION:  Stainless steel rod in sleeve         OPUS PID#: AJ6315
LATITUDE:   39° 33.5' N (  39.55830)          LONGITUDE:  75° 34.4' W ( -75.57330)


The bench mark is a flange-encased rod located on the west side of South Reedy
Point Road, 49.25 m (161.6 ft) north of power pole number 29, 33.60 m (110.2 ft)
south of the south side of the driveway for the residence at 270 South Reedy
Point Drive, 8.20 m (26.9 ft) west of the centerline of South Reedy Point Road,
and 6.25 m (20.5 ft) SSE of power pole number 30. The datum point is the top of
a stainless steel rod driven 18.0 m (59 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.



                         BENCH MARK STAMPING:  1910 K 1997
                         DESIGNATION:          855 1910 K

MONUMENTATION:           Flange-encased Rod                    VM#:        13760
AGENCY:                  National Ocean Service (NOS)          IDB PID#:  AJ6316
SETTING CLASSIFICATION:  Stainless steel rod in sleeve         OPUS PID:        
LATITUDE:   39° 32.7' N (  39.54500)          LONGITUDE:  75° 34.8' W ( -75.58000)


The bench mark is a flange-encased rod located on the east side of South Reedy
Point Road, 19.30 m (63.3 ft) NE of power pole 6, 9.86 m (32.4 ft) west of the
curb on the west side of Highway 9, 7.20 m (23.6 ft) east of the centerline of
South Reedy Point Road, and 0.25 m (0.8 ft) west of an orange fiberglass NOS
witness post. The datum point is the top of a stainless steel rod driven 11.9 m
(39 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  7 of  8

                                                                                
Station ID: 8551910                         PUBLICATION DATE:  09/27/2011
Name:       REEDY POINT, C&D CANAL                        
            DE
NOAA Chart: 12277                           Latitude:   39° 33.5' N (  39.55831)
USGS Quad:  DELAWARE CITY                   Longitude:  75° 34.4' W ( -75.57331)


                            T I D A L   D A T U M S 


Tidal datums at REEDY POINT, C&D CANAL 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 (04/17/2011)         =  2.816
     MEAN HIGHER HIGH WATER                     MHHW   =  1.780
     MEAN HIGH WATER                            MHW    =  1.683
     North American Vertical Datum              NAVD88 =  0.905
     MEAN SEA LEVEL                             MSL    =  0.890
     MEAN TIDE LEVEL                            MTL    =  0.869
     MEAN LOW WATER                             MLW    =  0.055
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (04/07/1982)         = -1.222

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     R 41 1979                                   1.620   -0.063
     1910 B 1979                                 3.268    1.585
     1910 C 1979                                 3.148    1.465
     1910 G 1982                                 2.390    0.707
     RP 3 1975                                   1.875    0.192
     RP 5 1975                                   2.325    0.642
     R 72 W                                      5.904    4.221
     1910 H 1997                                 1.784    0.101
     1910 J 1997                                 2.467    0.784
     1910 K 1997                                 2.534    0.851


                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  8 of  8

                                                                                
Station ID: 8551910                         PUBLICATION DATE:  09/27/2011
Name:       REEDY POINT, C&D CANAL                        
            DE
NOAA Chart: 12277                           Latitude:   39° 33.5' N (  39.55831)
USGS Quad:  DELAWARE CITY                   Longitude:  75° 34.4' W ( -75.57331)


                             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 8551910 Reedy Point, DE

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