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

                                                                                
Station ID: 9052030                         PUBLICATION DATE:  08/11/2017
Name:       OSWEGO, LAKE ONTARIO                              
            NY
NOAA Chart: 14813                           Latitude:   43° 27.9' N (  43.46417)
USGS Quad:  OSWEGO WEST                     Longitude:  76° 30.7' W ( -76.51183)


TO REACH THE NOS GAUGE, IN OSWEGO, OSWEGO COUNTY, NY, FROM THE INTERSECTION OF
WEST BRIDGE ST (HWY 104) AND 2ND ST, PROCEED NORTH ON EAST 2ND ST FOR 0.45 MILE
(0.72 KM) TO THE OSWEGO PORT AUTHORITY PROPERTY ENTRANCE, GAUGE IS LOCATED
INSIDE A 6 X 8 FT, ROOM IN THE LOWER SOUTHWEST CORNER OF THE PORT AUTHORITY OF
OSWEGO WAREHOUSE AND ON THE EAST SIDE OF THE OSWEGO RIVER.


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


                 PRIMARY BENCH MARK STAMPING:  LAKE 1948
                         DESIGNATION:          905 2030 LAKE

MONUMENTATION:           Metal Rod                             VM#:         1268
AGENCY:                  USLS                                  IDB PID#:  OF0658
SETTING CLASSIFICATION:  Metal rod driven into the ground      OPUS PID:        
LATITUDE:   43° 28.0' N (  43.46706)          LONGITUDE:  76° 30.5' W ( -76.50900)


BM Lake is about 83.8 m (275 ft) NE of ruins of former Coast Guard boathouse,
between railroad track and stone retaining wall along toe of the hill, about
57.0 m (187 ft) NE of gate in a fence. Bench mark is 10.9 m (35.7 ft) from stone
revetment along the lake shore, 1.2 m (3.8 ft) from most SE rail of the track,
0.3 m (1.0 ft) from face of the stone retaining wall, on line of arrow cut into
second course of stone from top of the retaining wall, flush with the ground
surface, being highest point on top of a 1-inch diameter iron rod, 1.5 m (5.0
ft) long. BM has 5 inch sleeve with aluminum cover and concrete kick block and
0.2m (0.7 ft) below grade.

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

                                                                                
Station ID: 9052030                         PUBLICATION DATE:  08/11/2017
Name:       OSWEGO, LAKE ONTARIO                              
            NY
NOAA Chart: 14813                           Latitude:   43° 27.9' N (  43.46417)
USGS Quad:  OSWEGO WEST                     Longitude:  76° 30.7' W ( -76.51183)


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


                         BENCH MARK STAMPING:   
                         DESIGNATION:          905 2030 OSWEGO

MONUMENTATION:           Bolt                                  VM#:         1272
AGENCY:                                                        IDB PID#:  OF0657
SETTING CLASSIFICATION:  Concrete                              OPUS PID:        
LATITUDE:   43° 27.9' N (  43.46561)          LONGITUDE:  76° 30.7' W ( -76.51119)


BM Oswego is near NE corner of main warehouse building occupied by Port of
Oswego Authority, on the loading dock which is attached to E face of building,
4.7 m (15.5 ft) S of the N edge of the loading dock, 15.2 cm (0.5 ft) from the
NE building corner, loading dock is about 1.2 m (4.0 ft) above the ground, being
highest point over a 1/2-inch diameter steel carriage bolt set into the
concrete.



                         BENCH MARK STAMPING:   
                         DESIGNATION:          905 2030 WILL

MONUMENTATION:           Bolt                                  VM#:         1273
AGENCY:                                                        IDB PID#:  OF0653
SETTING CLASSIFICATION:  Concrete floor                        OPUS PID:        
LATITUDE:   43° 27.9' N (  43.46436)          LONGITUDE:  76° 30.7' W ( -76.51117)


BM Will is on E side of the Oswego River near its mouth, inside of and near the
S end of main warehouse building occupied by the Port of Oswego Authority, 9.1
cm (0.3 ft) from outer angle formed by NE corner of wall dividing two-story
office facilities and general warehouse, being highest point on top of a
1/2-inch diameter steel carriage-bolt set into the concrete floor, mark is a
bolt head, part of which has rusted off, in addition, the concrete around the
mark is cracking.

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

                                                                                
Station ID: 9052030                         PUBLICATION DATE:  08/11/2017
Name:       OSWEGO, LAKE ONTARIO                              
            NY
NOAA Chart: 14813                           Latitude:   43° 27.9' N (  43.46417)
USGS Quad:  OSWEGO WEST                     Longitude:  76° 30.7' W ( -76.51183)


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


                         BENCH MARK STAMPING:   
                         DESIGNATION:          905 2030 SON

MONUMENTATION:           Bolt                                  VM#:         1276
AGENCY:                                                        IDB PID#:  OF0656
SETTING CLASSIFICATION:  Loading dock concrete surface         OPUS PID:        
LATITUDE:   43° 27.9' N (  43.46436)          LONGITUDE:  76° 30.6' W ( -76.51072)


BM Son is 4.6 m (15.0 ft) N of the S edge of loading dock, loading dock is about
1.2 m (4.0 ft) above the ground, 24.4 cm (0.8 ft) SE from the SE building
corner, being highest point on top of a 1/4-inch diameter steel bolt set into
the concrete loading dock and set flush with the loading dock surface.



                         BENCH MARK STAMPING:   
                         DESIGNATION:          905 2030 E

MONUMENTATION:           Survey disk                           VM#:         1277
AGENCY:                  US Army Corps of Engineers (USE)      IDB PID#:  OF0654
SETTING CLASSIFICATION:  Concrete                              OPUS PID:        
LATITUDE:   43° 27.8' N (  43.46417)          LONGITUDE:  76° 30.7' W ( -76.51142)


BM E is 14.5 m (45.7 ft) W of the SW corner of warehouse, 0.6 m (2.0 ft) E of
dock face, being highest point over cross at center of bronze disc set into the
concrete.

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

                                                                                
Station ID: 9052030                         PUBLICATION DATE:  08/11/2017
Name:       OSWEGO, LAKE ONTARIO                              
            NY
NOAA Chart: 14813                           Latitude:   43° 27.9' N (  43.46417)
USGS Quad:  OSWEGO WEST                     Longitude:  76° 30.7' W ( -76.51183)


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


                         BENCH MARK STAMPING:  2030 J 1997
                         DESIGNATION:          905 2030 J

MONUMENTATION:           Metal Rod                             VM#:        17014
AGENCY:                  National Ocean Service                IDB PID#:  AH9231
SETTING CLASSIFICATION:                                        OPUS PID:        
LATITUDE:   43° 28.0' N (  43.46664)          LONGITUDE:  76° 30.6' W ( -76.51081)


BM J is 85.5 m (280.6 ft) NE of the NE corner of warehouse, 42.9 m (140.7 ft) W
of center of track switch, 7.5 m (24.6 ft) SE of chiseled X in the top of the
end steel I-beam for guard rail, 4.01 m (13.15 ft) SW of chiseled X in S edge of
S rail for the most N track, 3.8 m (12.6 ft) SE of chiseled X in same track, 2.7
m (8.7 ft) S of chiseled X in same track, 6.0 m (19.7 ft) N of chiseled X in N
edge of N rail of S track, being highest point on top of a stainless steel rod,
the rod is 2 cm below ground with aluminum access cover flush with ground.  To
protect the BM, owner of property has put a heavy steel culvert opening with lid
over the mark.

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

                                                                                
Station ID: 9052030                         PUBLICATION DATE:  08/11/2017
Name:       OSWEGO, LAKE ONTARIO                              
            NY
NOAA Chart: 14813                           Latitude:   43° 27.9' N (  43.46417)
USGS Quad:  OSWEGO WEST                     Longitude:  76° 30.7' W ( -76.51183)


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


                         BENCH MARK STAMPING:  D
                         DESIGNATION:          D

MONUMENTATION:           Survey disk                           VM#:        18293
AGENCY:                  Army Corps of Engineers               IDB PID#:  DJ5176
SETTING CLASSIFICATION:  Unspecified Concrete                  OPUS PID#: DJ5176
LATITUDE:   43° 27.9' N (  43.46547)          LONGITUDE:  76° 30.7' W ( -76.51211)


BM D is 42.73 meters (140.19 ft) NW of the NW corner of the Ports bldg and
warehouse, 9.30 meters (30.51 ft) W of the E edge of the rounded bulkhead
corner, 8.26 meters (27.10 ft) N of the most N bollard, 0.88 meters (2.89 ft) E
of the W edge of the rounded bulkhead cell.





Foot Notes:

Above marks are published for informational purposes only.  Long term stability
has not been reviewed prior to publication.

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

                                                                                
Station ID: 9052030                         PUBLICATION DATE:  08/11/2017
Name:       OSWEGO, LAKE ONTARIO                              
            NY
NOAA Chart: 14813                           Latitude:   43° 27.9' N (  43.46417)
USGS Quad:  OSWEGO WEST                     Longitude:  76° 30.7' W ( -76.51183)


                             D E F I N I T I O N S


The International Great Lakes Datum (IGLD) is the vertical height reference
datum used in the Great Lakes/St. Lawrence River System for engineering,
charting, channel dredging, navigation safety, power generation, and water 
resource management. It is a coordinated datum between the United States and
Canada that ensures both countries are using the same reference for projects
in the Great Lakes basin. The datum origin, or zero, is defined as Mean Sea 
Level at Pointe-au-Pere /Rimouski, Quebec, Canada at the mouth of the 
St. Lawrence River. IGLD requires updating approximately every 25-30 years 
to account for varying changes in the land surface elevations following the 
retreat of the glaciers during the last ice age, referred to as Glacial 
Isostatic Adjustment (GIA). The current IGLD 1985 was implemented in 1992.

IGLD 1985 uses dynamic heights as the vertical reference standard and lakes
station water level elevations are adjusted to provide a level geopotential
plane for lake level reference.

Dynamic height is the potential difference along the plumbline between the 
vertical datum and a point of interest divided by a constant value of 
gravity. In Canada and USA, the constant value of gravity is the 
"normal gravity" on the ellipsoid at latitude 45 (9.806199 ms-2). Dynamic 
heights have no geometric meaning. They are mainly used for the management 
of water in large lakes, rivers and channels. The surface of a lake has a 
constant dynamic height if undisturbed by currents, winds, atmospheric 
pressure, etc.

The Hydraulic Corrector (HC) is the difference in the long term water level 
mean between Subordinate and Master station. The difference (HC) is 
subtracted algebraically at the subordinate gauge referencing the same 
elevation as the master station. Thus all water levels on a given lake can 
be referenced to the same lakes LWD/Chart Datum reference elevation.

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

                                                                                
Station ID: 9052030                         PUBLICATION DATE:  08/11/2017
Name:       OSWEGO, LAKE ONTARIO                              
            NY
NOAA Chart: 14813                           Latitude:   43° 27.9' N (  43.46417)
USGS Quad:  OSWEGO WEST                     Longitude:  76° 30.7' W ( -76.51183)


                             D E F I N I T I O N S


A Master Stations is the control point for determining water level 
elevations on a particular lake of the Great Lakes.   Since water surfaces
of the Great Lakes are considered to be at geopotential equal, all Mean 
Water Level (MWL) values for stations on a particular lake should have the 
same dynamic height.  Therefore, all subordinate water level station MWL 
values are adjusted to match the dynamic water level elevation of the Master
Station through the use of a hydraulic corrector.  In the establishment of 
International Great Lakes Datum (1985) the connecting waterways station 
dynamic elevations were calculated through the use of a linear regression 
while constraining the end points of the regression with the dynamic 
elevations of the corresponding master station above and below the 
connecting channel.

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 toNAVD88 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/.