Whenever any roadway has been divided into three or more clearly marked lanes for traffic the following rules in addition to all others consistent herewith shall apply:
 1. A vehicle shall be driven as nearly as practical entirely within a single lane and shall not be moved from such lane until the driver has first ascertained that such movement can be made with safety.

Terms Used In Iowa Code 321.306

  • Driver: means a person who operates a motor vehicle for the transportation of railroad workers in the motor vehicle on behalf of a railroad worker transportation company, whether the person is employed by the company for wages or drives for the company as an independent contractor. See Iowa Code 327F.39
  • following: when used by way of reference to a chapter or other part of a statute mean the next preceding or next following chapter or other part. See Iowa Code 4.1
  • highway: means the entire width between property lines of every way or place of whatever nature when any part thereof is open to the use of the public, as a matter of right, for purposes of vehicular travel, except in public areas in which the boundary shall be thirty-three feet each side of the center line of the roadway. See Iowa Code 321I.1
  • Roadway: means that portion of a highway improved, designed, or ordinarily used for vehicular travel. See Iowa Code 321I.1
  • Vehicle: means any vehicle as defined in chapter 321. See Iowa Code 321H.2
 2. If a roadway is divided into three lanes, a vehicle shall not be driven in the center lane except as follows:

 a. When overtaking and passing another vehicle where the roadway is clearly visible and such center lane is clear of traffic within a safe distance.
 b. In preparation for a left turn or where such center lane is at the time allocated exclusively to traffic moving in the direction the vehicle is proceeding and is signposted to give notice of such allocation.
 3. Official signs may be erected directing slow-moving traffic to use a designated lane or allocating specified lanes to traffic moving in the same direction and drivers of vehicles shall obey the directions of every such sign.
 4. Vehicles moving in a lane designated for slow-moving traffic shall yield the right-of-way to vehicles moving in the same direction in a lane not so designated when such lanes merge to form a single lane.
 5. A portion of a highway provided with a lane for slow-moving vehicles does not become a roadway marked for three lanes of traffic.
  Previous section
Next section  
 Chapter 321 Contents