The Code of Alabama 1975

Section 32-5A-171

Maximum limits.

Except when a special hazard exists that requires lower speed for compliance with Section 32-5A-170, the limits hereinafter specified or established as hereinafter authorized shall be maximum lawful speeds, and no person shall drive a vehicle at a speed in excess of the maximum limits.

(1) No person shall operate a vehicle in excess of 30 miles per hour in any urban district.

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(Acts 1980, No. 80-434, p. 604, §8-102; Acts 1987, No. 87-408, p. 593; Acts 1994, No. 94-617, p. 1147, §1; Acts 1996, No. 96-577, p. 913, §1.)

Section 32-5A-173

When local authorities may and shall alter maximum limits.

(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;

(2) Increases the limit within an urban district but not to more than the maximum rate of speed that may be prescribed by the Governor under subdivision (6) of Section 32-5A-171;

(3) Decreases the limit on any street, unpaved road, or highway under the jurisdiction and control of any county commission; or

(4) Increases the limit on any street, unpaved road, or highway under the jurisdiction and control of any county commission but not to more than the maximum rate of speed that is prescribed under subdivision (3) or by the Governor under subdivision (6) of Section 32-5A-171.

(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 this chapter 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 the street or highway.

(d) Any alteration of maximum limits on state highways or extensions thereof in a municipality by local authorities shall not be effective until the alteration has been approved by the Department of Transportation.

(e) Not more than six 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 10 miles per hour.

(Acts 1980, No. 80-434, p. 604, §8-104; Acts 1985, 2nd Ex. Sess., No. 85-998, p. 366, §2; Acts 1994, No. 94-617, p. 1147, §2.)

Section 32-5A-30

Uniform marking of highways and erection of traffic-control devices.

(a) The Department of Transportation is authorized to classify, designate, and mark both interstate and intrastate highways lying within the boundaries of this state.

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(c) No local authority shall place or maintain any traffic-control device upon any highway under the jurisdiction of the Department of Transportation except by the latter's permission.

(Acts 1980, No. 80-434, p. 604, §2-100.)

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