§ 50:2 — State plane coordinate system; zones

§2. State plane coordinate system; zones
A. The official geodetic datums for geodetic coordinates referenced within the state
shall be as defined by the National Spatial Reference System established by the National
Geodetic Survey of the National Oceanic and Atmospheric Administration, or its successors.
B.(1) The official state plane coordinate system for defining and stating the positions
or locations of points on the surface of the earth within the state is the most recent version
of the state plane coordinate system for Louisiana based on the National Spatial Reference
System established by the National Geodetic Survey and shall be known as the "Louisiana
Plane Coordinate System".
(2) For the purpose of using the Louisiana Plane Coordinate System, the state is
divided into three projection zone layers designated as the North Zone, the South Zone, and
the Statewide Zone, the areas of which are as follows:
(a) The area now included in the following parishes shall constitute the North Zone:
Avoyelles, Bienville, Bossier, Caddo, Caldwell, Catahoula, Claiborne, Concordia, DeSoto,
East Carroll, Franklin, Grant, Jackson, LaSalle, Lincoln, Madison, Morehouse, Natchitoches,
Ouachita, Rapides, Red River, Richland, Sabine, Tensas, Union, Vernon, Webster, West
Carroll, and Winn.
(b) The area now included in the following parishes extending to the coastal
boundary of Louisiana shall constitute the South Zone: Acadia, Allen, Ascension,
Assumption, Beauregard, Calcasieu, Cameron, East Baton Rouge, East Feliciana,
Evangeline, Iberia, Iberville, Jefferson, Jefferson Davis, Lafayette, Lafourche, Livingston,
Orleans, Plaquemine, Pointe Coupee, St. Bernard, St. Charles, St. Helena, St. James, St. John
the Baptist, St. Landry, St. Martin, St. Mary, St. Tammany, Tangipahoa, Terrebonne,
Vermilion, Washington, West Baton Rouge, and West Feliciana.
(c) The area now included in the areas of the North Zone and South Zone shall
constitute the Statewide Zone.
(3) For purposes of defining more precisely the Louisiana Plane Coordinate System,
the following definitions are adopted:
(a) The "Louisiana Plane Coordinate System North Zone" is a Lambert conformal
conic projection of the National Spatial Reference System NATRF2022 or its successors,
having a central parallel at north latitude 31 degrees 54 minutes 00 seconds, along which
parallel the scale shall be 0.999 93 (exact). The origin of the North Zone is at the
intersection of the meridian 92 degrees 30 minutes west longitude and the parallel 31 degrees
54 minutes 00 seconds north latitude. This origin is given the coordinates: x (east) = 495,300
meters and y (north) = 190,500 meters.
(b) The "Louisiana Plane Coordinate System South Zone" is a Lambert conformal
conic projection of the National Spatial Reference System NATRF2022 or its successors,
having a standard parallel at north latitude 30 degrees 00 minutes 00 seconds, along which
parallel the scale shall be 0.999 93 (exact). The origin of the South Zone is at the
intersection of the meridian 91 degrees 30 minutes 00 seconds west longitude and the parallel
30 degrees 00 minutes 00 seconds north latitude. This origin is given the coordinates: x
(east) = 609,600 meters and y (north) = 190,500 meters.
(c) The "Louisiana Plane Coordinate System Statewide Zone" has statewide
coverage. It is a Hotine Oblique Mercator projection of the National Spatial Reference
System NATRF2022 or its successors, having a north latitude of 31 degrees 00 minutes 00
seconds and a west longitude of 91 degrees 30 minutes, 00 seconds and a skew azimuth of
-68 degrees 00 minutes 00 seconds at that point, and the skew axis scale shall be 0.999 8
(exact). This origin is given the coordinates: x (east) = 914,400 meters and y (north) =
381,000 meters.
C. The provisions of this Section shall not be construed to prohibit the appropriate
use of other datums or geodetic reference networks when required and appropriate.

Legislative History

Acts 1968, No. 299, §1; Acts 1985, No. 913, §1; Acts 2024, No. 626, §2.