Louisiana Administrative Code
Title 43 - NATURAL RESOURCES
Part XXVII - State Lands
Subpart 1 - Land Information Mapping and Map Records System
Chapter 15 - Geographic Base Map
Section XXVII-1517 - Map Sheet Requirements

A. Map Scale. Final hard copy maps shall be at a scale of 1" = 50', 1" = 100', 1" = 200' or 1" = 400' based upon respective area classifications as set forth within Chapter 3.

B. Map Grid System. The map grid system established by these standards is based on a 1" = 400' basic regional map which is designated the "Basic Modular Unit." The Basic Modular Unit concept provides for a series of maps corresponding to each respective area classification at four separate scales which are defined as follows.

C. Grid System Numbering. Each Basic Modular Unit Map shall be identified by a map number derived from selected paired digits of the east and north coordinates of the southwest corner of the module. For example, a map with hypothetical lower left coordinates of E = 640,000 and N = 530,000 will be known as Map Number 6543. The digit "6" in the 100,000th place of the east coordinate is paired with the digit "5" in the 100,000th place of the north coordinate; the digit "4" in the 10,000th place of the east coordinate is paired with the digit "3" in the corresponding position in the north coordinate. These four digits uniquely define the modular map units within the area of jurisdiction of each parish. In parishes where the coordinate values equal or exceed 1,000,000 feet, the digit in the millionth place is redundant and will be dropped. However, the map must be clearly identified with its proper parish name and zone (north and south) of the Louisiana State Plane Coordinate System. Thus, a map in Orleans Parish having coordinates for the southwest corner of E = 3,700,000 and N = 540,000 can be identified as Orleans Parish Map Number 7504, Louisiana State Plane Coordinate System (South Zone). The map numbers at the 1" = 400' scale will contain only four digits. The map numbers at the 1" = 200' scale, the 1" = 100' scale and the 1" = 50' scale will contain only six digits. For these larger scales, the first four digits shall be those of the Basic Modular Unit with the addition of a two-digit suffix as shown in §1529, Appendix B. There will be a decimal point between the four digits of the Basic Modular Unit and the suffix. For example, a 1" = 200' map of Orleans Parish would be numbered 7504.03, a 1" = 100' map would be numbered 7504.15, and a 1" = 50' map would be numbered 7504.47 as shown in §1529, Appendix B.

D. Map Size. The outside edge dimensions of all hard-copy maps shall be 28 inches high by 36 inches long. The neat image area shall be 25 inches high by 25 inches long. A typical geographic base map sheet layout is included within §1531, Appendix C.

E. Map Title. A title to be prepared and approved by the responsible contracting authority shall be shown on each map sheet. The title shall denote as a minimum whether the map is planimetric or topographic, and the particular parish represented. A sample title block layout is included within §1533, Appendix D.

F. Grid Lines. Grid lines of the Louisiana State Plane Coordinate System (North or South Zone, as applicable) shall be plotted at 5-inch intervals. These grid lines shall be shown by solid black lines throughout the neat image area. The Louisiana State Plane Coordinates of the grid lines shall be printed in feet at 5-inch intervals in the margin along the image area border at the north, east, south and west sides of the map. Corresponding coordinate values in meters (rounded to the nearest millimeter) shall be printed along the image area border at the northeast, southeast, southwest and northwest corners of the map.

G. Graticule Ticks. Computer generated graticule ticks will be shown at the 10 second intervals of latitude and longitude at map scale along the image area border. The graticule ticks will appear as dashed black lines on the finished map sheets with appropriate values of latitude and longitude given for each graticule tick mark based on the Lambert Conformal Conic Projection defined by the NAD 83 Louisiana State Plane Coordinate System parameters.

H. Sheet Index. A sheet index diagram shall be included on each map sheet to indicate the map numbers of the adjoining sheets. This index will be placed in the margin outside the image area.

I. Legend and Margin Information. A legend of principal map symbols, north arrow, graphic bar scale, map number, horizontal and vertical control descriptions, and related margin data will appear in the right hand margin of the map sheet. All margin information will be placed on the geographic base map in such a fashion so that when this map is overprinted or layered with its companion parcel map, all marginal information from both maps will be clearly legible.