This chapter summarizes Iowa State statutes related to speed. I. The State may also establish a speed limit of 65 MPH on certain non-limited access divided multilaned highways. The State or a city may lower the 65 MPH speed limit upon highways located within the corporate limits of a city.
Local authorities have the authority to regulate the speed in public parks and alleys.
The Natural Resource Commission may reduce the speed limit on State parks and preserve roads when such is needed to improve safety. The Board of Regents may establish lower speed limits on roads under their jurisdiction in the interest of safety. I. A person shall not drive a motor vehicle at such a slow speed to impede or block the normal and reasonable movement of traffic. A vehicle, which cannot attain and maintain a speed of 40 MPH, cannot be driven on the interstate system. Based on engineering and traffic investigations, the State may establish a minimum speed limit on controlled-access, multilaned highways including interstate highways.