Iowa Code § 52.2: Optical scan voting system required.

Notwithstanding any provision to the contrary, for elections held on or after November 4, 2008, a county shall use an optical scan voting system only. The requirements of the federal Help America Vote Act, Pub. L. No. 107-252, 116 Stat. 1666, relating to disabled voters shall be met by a county through the use of electronic ballot marking devices that are compatible with an optical scan voting system.