Louisiana Revised Statutes Tit. 32, § 63. Establishing of speed zones

A. Whenever the department shall determine upon the basis of an engineering and traffic investigation that any maximum speed set forth in this Chapter is greater or less than is reasonable or safe under the conditions found to exist upon any highway of this state, or any part thereof, the department may determine and declare a reasonable and safe maximum speed limit thereat, which, when appropriate signs giving notice thereof are erected, shall be effective at all times or at such specific times as may be determined by the department.

B. Whenever the department determines on the basis of an engineering and traffic investigation that slow speeds on any highway of this state, or part thereof, consistently impede the normal and reasonable movement of traffic, the department may determine and declare a minimum speed limit thereat, below which no person shall drive a vehicle except when necessary for safe operation or in compliance with law. Minimum speeds so determined shall become effective upon the erection of signs giving notice thereof.

C. The department may establish a speed zone and may determine and declare a speed in excess of any maximum speed set forth in this Chapter within such speed zone on any highway of this state, whenever the department shall determine on the basis of an engineering and traffic investigation that such speed is reasonable and safe. The department shall erect appropriate signs giving notice thereof.