Iowa Code § 455B.223: Competent operator required.

It shall be unlawful for any person, firm, corporation, municipal corporation, or other governmental subdivision or agency, operating a water treatment plant, water distribution system, or wastewater treatment plant to operate same unless the competency of the operator to operate such plant or system is duly certified to by the director under the provisions of this part 2 of subchapter III. It shall also be unlawful for any person to perform the duties of an operator, as defined in this part, without being duly certified under the provisions of this part.