In accordance with requirements of the Iowa Department of Transportation, or whenever the City Council shall determine upon the basis of an engineering and traffic investigation that any speed limit listed in Section 62.01 is greater or less than is reasonable or safe under the conditions found to exist at any intersection or other place or upon any part of the City street system, the Council shall determine and adopt by resolution such higher or lower speed limit as it deems reasonable and safe at such location. Violations of this section shall be cited under Section 62.01(84) through 62.01(99), as is appropriate under the circumstances.
(Code of Iowa, Sec. 321.290)