North Dakota Century Code Title 39. Motor Vehicles § 39-09-04. Alteration of maximum speed limits on state highways

The maximum speed limits specified in section 39-09-02 may be altered on all or any part of the state highway system by an administrative order by the director after holding a public hearing. The determination must be based on engineering and traffic investigations with primary consideration given to the establishment of reasonable and safe speeds, highway conditions, enforcement, and the general welfare. Speed limits established under this section are effective only when appropriate signs giving notice are erected and the maximum speed limits may be declared effective at all times or at the times indicated on the signs. Differing limits may be established by the director for different times of the day, different types of vehicles, varying weather conditions, and other factors bearing on safe speeds. Differing limits are effective when posted on appropriate fixed or variable signs. An administrative order is not required to lower maximum speed limits temporarily due to unsafe conditions.