045-I Wyo. Code R. § 1.1
(1) Title 31, Chapter 5 - Article 3 of the Wyoming Statutes establishes the speed regulations for all public roadways in Wyoming. Effective July 1, 2011, the statutory speed limits are:
(a) 20 mph in school zones
(b) 30 mph in urban districts, as defined by W.S. 31-5-102(a) (lvii)
(c) 30 mph in any residence district, as defined by W.S. W.S. W.S. 31-5-102(a) (xxxviii)
(d) 30 mph in any subdivision, pursuant to W.S. W.S. W.S. 18-5-304
(e) 75 mph on interstate highways
(f) 65 mph on all other paved roadways
(g) 55 mph on all other unpaved roadways
(2) The statutes, under W.S. W.S. W.S. 31-5-303, authorize local authorities to establish specific maximum speed limits on all streets and highways within their respective corporate jurisdiction. Such speed limits may be greater or less than the normal statutory speed limits for the roadways being considered.
(3) The statutes also include a basic speed law [W.S. W.S. W.S. 31-5-301(a) ], prohibiting drivers from traveling at a speed greater than what is reasonable and prudent under the conditions and having regard to the actual and potential hazards that may exist, which recognizes that driving conditions and speeds may vary widely from time to time. No posted speed limit can adequately serve all driving conditions. Motorists must constantly adjust their driving behavior to fit the conditions they encounter.
(4) Any speed limit, other than a statutory speed limit listed above, that is posted on Wyoming paved roads open to the public shall be based on criteria contained in this procedure and be consistent with national practices. Criteria used to set a speed limit shall include an analysis of free-flow traffic speeds. A spot speed analysis is used to measure the free-flowing traffic speed characteristics at a specified location under the traffic and environmental conditions prevailing at the time of the analysis. The purpose of this document is to establish the proper procedures for completing an analysis in accordance with the statutes, to provide guidance in setting appropriate speed limits based on data, and to establish the documentation and notification procedures when establishing new speed limits.
045-I Wyo. Code R. § 1.1