(1) A vehicle shall only be driven, as nearly as practicable, entirely within a single lane and shall not be moved from that lane until the driver has first ascertained that the movement can be made with safety.

(2) Upon a roadway which is divided into three lanes and provides for two-way movement of traffic, a vehicle may be driven in the center lane only when overtaking and passing another vehicle traveling in the same direction when the center lane is clear of traffic within a safe distance, or in preparation for making a left turn, or where the center lane is at the time allocated exclusively to traffic moving in the same direction that the vehicle is proceeding and the allocation is designated by official traffic-control devices.

(3) Official traffic-control devices may be erected directing specified traffic to use a designated lane or designating those lanes to be used by traffic moving in a particular direction regardless of the center of the roadway, and drivers of vehicles shall obey the directions of the signs.

(4) Official traffic-control devices may be installed prohibiting the changing of lanes on sections of roadway, and drivers of vehicles shall obey the directions of these devices. (Added 1971, No. 258 (Adj. Sess.), § 3, eff. March 1, 1973.)