U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of 10

                                                                                
Station ID: 9063012                         PUBLICATION DATE:  08/11/2017
Name:       NIAGARA INTAKE, NIAGARA FALLS, NIAGARA R          
            NY
NOAA Chart: 14822                           Latitude:   43°  4.6' N (  43.07692)
USGS Quad:                                  Longitude:  79°  0.8' W ( -79.01389)


TO REACH THE NOS GAUGING STATION, IN NIAGARA COUNTY, NEW YORK, FROM THE
INTERSECTION OF I-190 (GRAND ISLAND BRIDGE) AND ROBERT MOSES PARKWAY, PROCEED
WEST ON ROBERT MOSES PARKWAY FOR APPROX 2.25 KM (1.40 MI) , THE ETG IS IN THE
NIAGARA FRONTIER PARK, JUST SOUTH SOUTHEAST OF THE EASTERLY ONE OF TWO NEW YORK
POWER AUTHORITY (NYPA) INTAKE STRUCTURES ON THE SOUTH SIDE OF ROBERT MOSES
PARKWAY, THE GAUGE HOUSE IS A 10' X 1O' BUILDING WITH STAINLESS STEEL SIDING.


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


                 PRIMARY BENCH MARK STAMPING:  INTAKE 1963
                         DESIGNATION:          906 3012 INTAKE

MONUMENTATION:           Survey disk                           VM#:        12774
AGENCY:                  Army Corp of Engineers                IDB PID#:  OG0215
SETTING CLASSIFICATION:  Intake foundation                     OPUS PID:        
LATITUDE:   43°  4.7' N (  43.07756)          LONGITUDE:  79°  1.0' W ( -79.01694)


The bench mark is a disk on the S side of Robert Moses Parkway, near river face
of W intake structure of the New York State Power Authority, 14.4 m (47.2 ft) SW
of SE corner, 3.4 m (11.2 ft) ENE of SW corner of the intake structure, 0.9 m
(3.0 ft) S of the S face of concrete base of intake structure, being the highest
point over cross at center of bronze disc set into concrete walk which is part
of the intake structure that is sitting on bedrock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of 10

                                                                                
Station ID: 9063012                         PUBLICATION DATE:  08/11/2017
Name:       NIAGARA INTAKE, NIAGARA FALLS, NIAGARA R          
            NY
NOAA Chart: 14822                           Latitude:   43°  4.6' N (  43.07692)
USGS Quad:                                  Longitude:  79°  0.8' W ( -79.01389)


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


                         BENCH MARK STAMPING:  BM
                         DESIGNATION:          906 3012 EWI

MONUMENTATION:           Bolt                                  VM#:        12773
AGENCY:                                                        IDB PID#:  OG0354
SETTING CLASSIFICATION:  Intake Structure                      OPUS PID:        
LATITUDE:   43°  4.6' N (  43.07717)          LONGITUDE:  79°  0.9' W ( -79.01433)


The bench mark is a bolt on the S side of Robert Moses Parkway, near the SW
corner of the W face of E one of two New York Power Authority water intake
structures,  8.41 m (27.59 ft) S of NW corner of water intake structure, 5.6 m
(18.4 ft) N of SW corner, 1.8 m (5.9 ft) S of the S edge of the doorway
entrance, 1.5 m (4.9 ft) above the sidewalk, being horizontal line at center of
a 0.5 x 0.75 inch rectangular-headed brass bolt with rounded corners.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of 10

                                                                                
Station ID: 9063012                         PUBLICATION DATE:  08/11/2017
Name:       NIAGARA INTAKE, NIAGARA FALLS, NIAGARA R          
            NY
NOAA Chart: 14822                           Latitude:   43°  4.6' N (  43.07692)
USGS Quad:                                  Longitude:  79°  0.8' W ( -79.01389)


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


                         BENCH MARK STAMPING:  Z 411 1977
                         DESIGNATION:          Z 411

MONUMENTATION:           Bench Mark disk                       VM#:        12775
AGENCY:                  National Geodetic Survey              IDB PID#:  OG0353
SETTING CLASSIFICATION:  Copper-clad steel rod w/o sleeve      OPUS PID:        
LATITUDE:   43°  4.7' N (  43.07853)          LONGITUDE:  79°  1.1' W ( -79.01756)


The bench mark is a disk on the median of Robert Moses Parkway, between the N
and S bound lanes, 74.4 m (244.1 ft) N of the most N of two intake towers, 31.2
m (102.4 ft) E of the E side of a turn-around of the highway, 16.67 m (54.69 ft)
S of the centerline of the N bound lane of Robert Moses Parkway, 14.2 m (46.6
ft) N of the centerline of the S bound lane, being a disc crimped atop a 5/8
inch copper coated steel rod driven to a depth of 6.1 m (20.0 ft) , encased in a
5-inch pvc pipe with an ngs logo cap and concrete kickblock with witness post.



                         BENCH MARK STAMPING:   
                         DESIGNATION:          906 3012 RAIL

MONUMENTATION:           Survey disk                           VM#:        12777
AGENCY:                  Army Corp of Engineers                IDB PID#:  OG0217
SETTING CLASSIFICATION:  Concrete Sidewalk                     OPUS PID#: OG0217
LATITUDE:   43°  4.6' N (  43.07664)          LONGITUDE:  79°  0.8' W ( -79.01250)


The bench mark is a disk on the the S side of Robert Moses Parkway, 137.2 m
(450.1 ft) E of E of two intake structures, 72.9 m (239.2 ft) W along seawall
from an angle in the wall, 9.55 m (31.33 ft) WSW of the W edge of a asphalt bike
path, 7.96 m (26.12 ft) SW of the SW corner of square concrete storm drain, 1.8
m (5.9 ft) N of river face of concrete breakwall, 18.3 cm (7.2 in) S of N edge
of concrete walk, being highest point over cross at center of bronze disc set
into the concrete walk.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of 10

                                                                                
Station ID: 9063012                         PUBLICATION DATE:  08/11/2017
Name:       NIAGARA INTAKE, NIAGARA FALLS, NIAGARA R          
            NY
NOAA Chart: 14822                           Latitude:   43°  4.6' N (  43.07692)
USGS Quad:                                  Longitude:  79°  0.8' W ( -79.01389)


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


                         BENCH MARK STAMPING:  AJAX
                         DESIGNATION:          906 3012 AJAX

MONUMENTATION:           Survey disk                           VM#:        12780
AGENCY:                  US Lake Survey                        IDB PID#:  OG0194
SETTING CLASSIFICATION:  Tower Foundation                      OPUS PID:        
LATITUDE:   43°  4.8' N (  43.07989)          LONGITUDE:  79°  0.9' W ( -79.01428)


The bench mark is a disk 135.9 m (445.9 ft) S of S curb of Buffalo Avenue, on
concrete foundation which used to support the SE leg of a large double-bent
transmission tower no.  25, on E-W centerline of the footing, 29.9 m (98.1 ft) S
of the SE leg of tower T291, 13.9 m (45.6 ft) SSW of a fire hydrant, 11.4 m
(37.4 ft) NNE of most N train rail, 8.05 m (26.41 ft) SW of power pole marked
Bell Atlantic no.5, 7.03 m (23.06 ft) NW of centerline of Iroquois Ave curb,
flush with the ground surface, being highest point over cross at center of
bronze disc set into the concrete, near the SE edge of the concrete.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of 10

                                                                                
Station ID: 9063012                         PUBLICATION DATE:  08/11/2017
Name:       NIAGARA INTAKE, NIAGARA FALLS, NIAGARA R          
            NY
NOAA Chart: 14822                           Latitude:   43°  4.6' N (  43.07692)
USGS Quad:                                  Longitude:  79°  0.8' W ( -79.01389)


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


                         BENCH MARK STAMPING:  A 412 1977
                         DESIGNATION:          A 412

MONUMENTATION:           Bench Mark disk                       VM#:        12781
AGENCY:                  National Geodetic Survey              IDB PID#:  OG0355
SETTING CLASSIFICATION:  Seawall                               OPUS PID:        
LATITUDE:   43°  4.6' N (  43.07689)          LONGITUDE:  79°  0.8' W ( -79.01411)


The bench mark is a disk on the S side of Robert Moses Parkway, 38.2 m (125.3
ft) SE of the SW corner of the S tower, 5.45 m (17.88 ft) SSW of the NW corner
of gauge house, 3.59 m (11.78 ft) SW of the SW corner of gauge house, 0.25 m
(0.82 ft) N of guard rail which runs E-W of Niagara River.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of 10

                                                                                
Station ID: 9063012                         PUBLICATION DATE:  08/11/2017
Name:       NIAGARA INTAKE, NIAGARA FALLS, NIAGARA R          
            NY
NOAA Chart: 14822                           Latitude:   43°  4.6' N (  43.07692)
USGS Quad:                                  Longitude:  79°  0.8' W ( -79.01389)


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


                         BENCH MARK STAMPING:  Y 411 1977
                         DESIGNATION:          Y 411

MONUMENTATION:           Bench Mark disk                       VM#:        12782
AGENCY:                  National Geodetic Survey              IDB PID#:  OG0352
SETTING CLASSIFICATION:  Abutment                              OPUS PID:        
LATITUDE:   43°  4.7' N (  43.07853)          LONGITUDE:  79°  1.6' W ( -79.02600)


The bench mark is a disk on the S of Robert Moses Parkway, in the SW bridge
abutment, 20.1 m (65.9 ft) W of the E end of concrete bridge abutment, 15.4 m
(50.52 ft) N of the S end of the abutment wing wall, 0.29 m (0.95 ft) S of the N
edge of concrete abutment.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  7 of 10

                                                                                
Station ID: 9063012                         PUBLICATION DATE:  08/11/2017
Name:       NIAGARA INTAKE, NIAGARA FALLS, NIAGARA R          
            NY
NOAA Chart: 14822                           Latitude:   43°  4.6' N (  43.07692)
USGS Quad:                                  Longitude:  79°  0.8' W ( -79.01389)


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


                         BENCH MARK STAMPING:  X 411 1977
                         DESIGNATION:          X 411

MONUMENTATION:           Tidal Station disk                    VM#:        13025
AGENCY:                                                        IDB PID#:  OG0351
SETTING CLASSIFICATION:                                        OPUS PID:        
LATITUDE:   ' °deg (0)          LONGITUDE:  ' °deg (0)




                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  8 of 10

                                                                                
Station ID: 9063012                         PUBLICATION DATE:  08/11/2017
Name:       NIAGARA INTAKE, NIAGARA FALLS, NIAGARA R          
            NY
NOAA Chart: 14822                           Latitude:   43°  4.6' N (  43.07692)
USGS Quad:                                  Longitude:  79°  0.8' W ( -79.01389)


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


                         BENCH MARK STAMPING:  V411 1977
                         DESIGNATION:          V 411

MONUMENTATION:           Bench Mark disk                       VM#:        17006
AGENCY:                                                        IDB PID#:  OG0347
SETTING CLASSIFICATION:                                        OPUS PID:        
LATITUDE:   43°  4.9' N (  43.08167)          LONGITUDE:  79°  3.7' W ( -79.06167)






                         BENCH MARK STAMPING:  906 3012 J 2013
                         DESIGNATION:          906 3012 J

MONUMENTATION:           Metal Rod                             VM#:        20867
AGENCY:                  National Ocean Service                IDB PID#:        
SETTING CLASSIFICATION:  Metal rod driven into the ground      OPUS PID:        
LATITUDE:   43°  4.6' N (  43.07656)          LONGITUDE:  79°  0.7' W ( -79.01100)


The bench mark is a metal rod 47.4 m (155.5 ft) ESE of a 25 cm diameter tree in
the E side of an open field S of the Robert Moses Parkway, 26.2 m (86.0 ft) SSE
of the center line of the S-bound lane of the Robert Moses Parkway, 14.7 m (48.2
ft) NE of the center line of an asphalt jogging path, 15 cm W of a NOS witness
post.





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  9 of 10

                                                                                
Station ID: 9063012                         PUBLICATION DATE:  08/11/2017
Name:       NIAGARA INTAKE, NIAGARA FALLS, NIAGARA R          
            NY
NOAA Chart: 14822                           Latitude:   43°  4.6' N (  43.07692)
USGS Quad:                                  Longitude:  79°  0.8' W ( -79.01389)


                             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 10 of 10

                                                                                
Station ID: 9063012                         PUBLICATION DATE:  08/11/2017
Name:       NIAGARA INTAKE, NIAGARA FALLS, NIAGARA R          
            NY
NOAA Chart: 14822                           Latitude:   43°  4.6' N (  43.07692)
USGS Quad:                                  Longitude:  79°  0.8' W ( -79.01389)


                             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/.