Current through Register Vol. 50, No. 9, September 20, 2024
A. In
addition to the requirements for planimetric maps set forth above, topographic
maps shall be prepared to include the following information:
1. contour lines shall be shown at vertical
intervals established and specified by the responsible contracting authority.
Every fifth contour line will be coded as an index contour which can be
symbolized as a line of heavier weight than that of intermediate contours and
shall be expressed as a heavier weight line on the digital data base hard-copy
delivery maps. Index contours shall be labeled inside a "break" in the line
every 6 to 12 inches at map scale. In those areas where vegetation prohibits
accurate plotting of contour line elevations, the contour line elevations will
be interpolated as accurately as possible from spot elevations measured
photogrammetrically in places where the ground is visible. All contour lines
will be solid and unbroken except where they pass through dense ground cover,
in which case dashed lines must be used;
2. spot elevations will be determined
photogrammetrically and shall be placed at hilltops, saddles, ridgelines,
bottoms of depressions, intersections of principal streets, intersections of
highways, ends of bridges, and water levels of lakes, reservoirs and ponds.
Spot elevations shall also be determined and placed at maximum 400-foot
intervals along the tops of all levees and floodwalls within the project area.
In areas where contours are more than one inch apart at map scale, additional
spot elevations shall be shown at approximately 1-inch intervals to accurately
portray the character of the topography throughout the project area;
3. auxiliary heights shall consist of the
photogrammetric determination of the heights of buildings, wooded areas, signs,
billboards, towers and other specified features at the discretion of the
responsible contracting authority. Auxiliary heights are intended to be an
approximate representation of the vertical character of such features for
nonprecision applications.
B. The primary topographic features to be
mapped are identified within §1527, Appendix A, included herewith. Photo
identifiable features required by the responsible contracting authority and not
specifically listed in §1527, Appendix A, shall also be captured and
categorized.
C. Each topographic
feature mapped will be identified and stored digitally by a specific feature
code as listed and described within Chapter 19. Any topographic features when
identifiable which are not included within the list of feature elements shall
be defined by appropriate outline, symbol and/or annotation by using feature
code additions to the data aggregation.
AUTHORITY NOTE:
Promulgated in accordance with
R.S.
50:171.