Survey Control Monuments

 
 

Purpose
The Geographic Reference System (GRS) created resulted in a network of accurately positioned horizontal and vertical control monuments (latitude, longitude, elevation, and state plane coordinates) to be used by land surveyors, engineers, cartographers, and others who have a need to locate positions on, below, or above the surface of the earth. St. Clair County now has a usable GRS that will provide a common coordinate base for use by the county, surveyors, civil engineers, contractors, and developers. It is imperative that local surveyors have access to monuments and data on a common coordinate system. The coordinate system is the Illinois State Plane Coordinate System (ISPCS) which utilizes the North American Datum of 1983 (NAD 83).

The Federal Framework
The National Geodetic Survey (NGS) is a Federal agency responsible for the National Spatial Reference System (NSRS) throughout the United States and its territories inclusive of the Caribbean and parts of South America. Presently NGS defines and manages the NSRS which provides the foundation for transportation and communication; mapping and charting; and a multitude of scientific and engineering applications. Additionally, NGS develops Federal standards for geodetic surveys and regulates coordinate surveying methods. NGS State Geodetic Advisors are stationed in several states to work with local communities to expand surveying capabilities.

Designation
Latitude - NAD 1983 (2007)
Longitude - NAD 1983 (2007)
Grid Northing Illinois West Zone (1202)
Grid Easting Illinois West Zone (1202)
Elevation (NAVD 1988) +/- 0.2'
Grid Scale Factor
Combined Factor
Convergence
 
             
 
 
 
 
 
 
 
 
 
 
 
             
 
A 249
38°37'21.46591"N
90°03'32.52090"W
712218.467
2327333.407
420.2
0.999942258
0.99992704
0°04'02"
CHOCTAW
38°33'15.82436"N
89°48'09.22682"W
687557.526
2400704.022
443.6
0.999953575
0.99993719
0°13'37"
CHOCTAW AZ MK
38°33'15.11142"N
89°47'47.90585"W
687492.167
2402397.939
438.3
0.999953982
0.99993786
0°13'50"
E 285
38°31'26.75989"N
90°14'47.42760"W
676328.369
2273742.103
426.7
0.999941773
0.99992621
-0°02'59"
SCCB
38°30'46.12669"N
89°59'05.86008"W
672259.385
2348574.508
619.5
0.999944268
0.99991949
0°06'47"
 
38°37'22.36498"N
89°52'27.44944"W
712424.420
2380112.797
488.2
0.999949156
0.999930670
0°10'57"
 
 
38°37'01.37509"N
89°52'26.14571"W
710301.393
2380223.031
509.8
0.999949177
0.999929660
0°10'58"
 
 
38°26'18.09759"N
89°47'05.85111"W
645321.144
2405913.497
421.5
0.999954847
0.999939490
0°14'14"
 
 
38°26'18.43190"N
89°46'48.39179"W
645360.751
2407302.460
414.1
0.999955197
0.999940190
0°14'25"
 
 
38°17'38.28656"N
89°46'17.57664"W
592754.936
2409979.401
420.7
0.999955883
0.999940510
0°14'41"
 
 
38°17'37.54126"N
89°46'37.97958"W
592672.644
2408353.184
448.3
0.999955465
0.999938780
0°14'29"
 
 
38°20'49.70404"N
89°56'37.76842"W
611952.653
2360490.727
434.9
0.999945848
0.999929830
0°08'18"
 
 
38°20'05.40347"N
89°56'29.01680"W
607473.080
2361198.830
428.4
0.999945952
0.999930240
0°08'23"
 
 
38°26'51.58385"N
90°05'29.47768"W
648490.901
2318103.859
599.5
0.999941706
0.999917860
0°02'48"
 
 
38°26'39.66464"N
90°05'45.62173"W
647284.167
2316820.495
606.4
0.999941645
0.999917470
0°02'38"
 
 
38°31'49.82778"N
90°14'36.75659"W
678661.172
2274592.054
427.3
0.999941730
0.999926160
-0°02'52"
 
 
38°37'21.67513"N
90°03'54.56675"W
712237.640
2325583.839
433.1
0.999942138
0.999926310
0°03'48"
 
 
38°16'16.71385"N
89°51'44.74457"W
584404.798
2383924.544
421.8
0.999949902
0.999934490
0°11'18"
 
 
38°16'17.83253"N
89°52'17.21953"W
584509.567
2381334.459
422.3
0.999949392
0.999933950
0°10'58"
TURKEY HILL
38°28'33.06779"N
89°54'16.42804"W
658854.805
2371616.983
644.0
0.999947616
0.999921650
0°09'47"
 
 
 
 
 
 
 
 
 
Prepared by:
         
Horizontal Datum:
 
   Norman R. Brown, P.L.S.
       
   North American Datum of 1983 (2007)
   Kuhlmann design Group, Inc.
       
Vertical Datum:
 
 
   15 East Washington Street
       
   North American Vertical Datum of 1988
   Belleville, IL   62220
         
Coordinate System:
 
 
 
         
   Illinois West Zone (1202)
 
 
         
Units:
 
 
 
         
   U.S. Survey Foot
 
 
 
 
 
 
 
   (1 meter=3.280833333333 U.S. Survey  Feet)