ARTICLE 3 - SPEED REGULATIONS

(a) No person shall drive a vehicle on a highway at a speed greater than is reasonable and prudent under the conditions and having regard to the actual and potential hazards then existing. Consistent with the foregoing, every person shall drive at a safe and appropriate speed when approaching and crossing an intersection or railroad grade crossing, when approaching and going around a curve, when approaching a hillcrest, when traveling upon any narrow or winding roadway and when special hazards exist with respect to pedestrians or other traffic or by reason of weather or highway conditions.

(b) Except when a special hazard exists that requires lower speed for compliance with subsection (a) of this section, subject to W.S. 31-5-203(b), the limits specified in this subsection or established as otherwise authorized shall be maximum lawful speeds and no person shall drive a vehicle on a highway at a speed in excess of maximum limits:

(i) Twenty (20) miles per hour when passing a school building, the grounds thereof, within any other area or space in the vicinity of a school designated by an official traffic control device as a school zone with a reduced speed limit or a school crossing if appropriate signs giving notice of a reduced speed limit are erected;

(ii) Thirty (30) miles per hour in any urban district and in any residence district or subdivision except on roads that have been designated a private road pursuant to W.S. 18-5-306(a)(vii);

(iii) Except as provided under paragraph (vi) of this subsection, seventy-five (75) miles per hour on interstate highways. Nothing in this paragraph shall be construed to:

(A) Affect the authority of the superintendent to otherwise designate lower or higher maximum speed limits on interstate highways in accordance with other laws; or

(B) Authorize noncompliance with posted speed limits on interstate highways.

(iv) For all other locations for which a maximum speed limit is not specified under this subsection, sixty-five (65) miles per hour where the roadway is paved and fifty-five (55) miles per hour where the roadway is unpaved;

(v) Repealed By Laws 1997, ch. 61, § 2.

(vi) Notwithstanding paragraph (iii) of this subsection, eighty (80) miles per hour on interstate highways designated by the superintendent;

(vii) Seventy (70) miles per hour on state highways, as defined in W.S. 31-18-101(a)(xvii), that are not interstate highways, as defined in W.S. 31-18-801(a)(xvi).

(c) Subject to W.S. 31-5-203(b), the maximum speed limits set forth in this section may be altered as authorized in W.S. 31-5-302 and 31-5-303.

(d) Speeding violations of up to eighty (80) miles per hour where the posted speed limit is at least sixty-five (65) miles per hour but not more than seventy-five (75) miles per hour, or less than six (6) miles per hour over the posted speed limit in all other instances and zones, except violations for exceeding the speed limit in a school zone, or construction zone, and violations received while operating a commercial motor vehicle as defined by W.S. 31-7-102(a)(viii), shall not be made a part of the abstracts or records kept by the department of transportation pursuant to W.S. 31-5-1214 or 31-7-120.

Whenever the superintendent determines upon the basis of an engineering and traffic investigation, or in the event of a vehicle or weather emergency, that a maximum speed greater or less than that authorized herein is safe and reasonable under the conditions found to exist at any intersection or other place or upon any part of the state highway system, the superintendent, except as provided for in W.S. 31-5-303(b), may determine and declare a reasonable and safe maximum limit thereat, which shall be effective when appropriate signs giving notice thereof are erected and which shall not exceed eighty (80) miles per hour on interstate highways. The maximum speed limit may be declared to be effective at all times or at such times as are indicated upon the signs and differing limits may be established for different times of day, different types of vehicles, varying weather conditions, and other factors bearing on safe speeds, which shall be effective when posted upon appropriate fixed or variable signs. This section does not grant power to the superintendent to declare statewide or countywide maximum speed limits but grants power to declare maximum speed limits for the public safety in localized geographic areas.

(a) Repealed By Laws 2002, Ch. 68, § 2.

(b) Except as provided in subsection (f) of this section, in compliance with rules promulgated by the department, local authorities in their respective jurisdictions may determine the proper maximum speed for all streets and highways within their respective corporate jurisdiction which maximum speed is reasonable and safe and which may be greater or less than the maximum speed permitted under this act. The rules promulgated by the department shall adopt standards consistent with national practices. The department shall not promulgate rules that require a speed study before a local authority establishes a maximum speed limit for unpaved roads in accordance with subsection (f) of this section.

(c) Any altered limit established under this section shall be effective 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 is not effective until the alteration has been approved by the superintendent.

(e) Not more than six (6) alterations authorized under this section 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 fifteen (15) miles per hour.

(f) A local authority may decrease a maximum speed limit to not less than thirty-five (35) miles per hour for unpaved roadways under W.S. 31-5-301(b)(iv) without first conducting a speed study. A local authority may establish a temporary speed limit of less than thirty-five (35) miles per hour without conducting a speed study and for a period not exceeding one (1) year for purposes including, but not limited to, construction, maintenance, special events, emergency situations and changes in use. Before establishing a temporary speed limit of less than thirty-five (35) miles per hour, the local authority shall consult with the local authority's engineer or road and bridge superintendent and law enforcement with jurisdiction over the roadway.

(a) No person shall drive a motor vehicle at such a slow speed as to impede the normal and reasonable movement of traffic except when reduced speed is necessary for safe operation or in compliance with law.

(b) Whenever the superintendent determines on the basis of an engineering and a traffic investigation that slow speeds on any part of a highway consistently impede the normal and reasonable movement of traffic, the superintendent may determine and declare a minimum speed limit below which no person shall drive a vehicle except when necessary for safe operation or in compliance with law and that limit is effective when posted upon appropriate fixed or variable signs. A local authority may make the determination permitted under this subsection by complying with rules adopted by the department for this purpose, which rules shall adopt standards consistent with national practices.

(c) Notwithstanding any minimum speed that may be authorized and posted pursuant to this section, no person shall operate a vehicle in the extreme left-hand lane of a controlled-access highway for a prolonged period in a manner which impedes the flow of other traffic traveling at a lawful rate of speed.

(a) No person shall drive a vehicle over any bridge or other elevated structure constituting a part of a highway at a speed which is greater than the maximum speed which can be maintained with safety to the bridge or structure when the structure is signposted as provided in this section.

(b) The superintendent and local authorities on highways under their respective jurisdictions may conduct an investigation of any bridge or other elevated structure constituting a part of a highway, and if he or they find that the structure cannot with safety to itself withstand vehicles traveling at the speed otherwise permissible under this act, the superintendent or local authorities shall determine and declare the maximum speed of vehicles which the structure can safely withstand and shall cause or permit suitable signs stating the maximum speed to be erected and maintained before each end of the structure.

(c) Upon the trial of any person charged with a violation of this section, proof of the determination of the maximum speed by the superintendent and the existence of the signs constitutes conclusive evidence of the maximum speed which can be maintained with safety to the bridge or structure.

(a) In every charge of violation of any speed regulation in this act except a charge under W.S. 31-5-301(a) the complaint, also the summons or notice to appear, shall specify the speed at which the defendant is alleged to have driven, also the maximum speed applicable within the district or at the location.