A. Whenever local authorities in their respective jurisdictions determine on the basis of an engineering and traffic investigation that the maximum speed permitted under this article is greater or less than is reasonable and safe under the conditions found to exist upon a highway or part of a highway, the local authority may determine and declare a reasonable and safe maximum limit thereon which:

1. Decreases the limit at intersections; or

2. Increases the limit within an urban district, but not to more than sixty-five (65) miles per hour; or

3. Decreases the limit outside an urban district, but not to less than thirty (30) miles per hour.

B. Local authorities in their respective jurisdictions shall determine by an engineering and traffic investigation the proper maximum speed for all arterial streets and shall declare a reasonable and safe maximum limit thereon which may be greater or less than the maximum speed permitted under Section 1-101 et seq. of this title for an urban district.

C. Any altered limit established as hereinabove authorized shall be effective at all times or during hours of darkness or at other times as may be determined when appropriate signs giving notice thereof are erected upon such street or highway.

D. As to streets and highways within the corporate limits which have been constructed or reconstructed with state or federal funds, local authorities shall have joint authority with the Transportation Commission to establish or alter speed limits; provided, however, the speed limit on an interstate highway within such corporate limits shall not be decreased to less than sixty (60) miles per hour; and provided further, that no local authority shall impose speed limits on any such street or highway substantially lower than those justified by the highway design, capacity, and traffic volume as determined by engineering studies.

E. Not more than six such alterations as hereinabove authorized shall be made per mile along a street or highway except in the case of reduced limits at intersections, and the difference between adjacent limits shall not be more than ten (10) miles per hour.

Added by Laws 1961, p. 385, § 11-803, eff. Sept. 1, 1961. Amended by Laws 1991, c. 98, § 5, eff. July 1, 1991; Laws 1996, c. 324, § 2.