Iowa Code § 49.6: Power to combine township and city precincts.

Election precincts composed partially of unincorporated territory and partially of all or any part of a city may be established within a single county in any manner which is not contrary to section 49.3. An agreement mutually satisfactory to the board of supervisors or the temporary county redistricting commission and the city council of the city involved shall be adopted and a copy of the agreement shall be submitted to the state commissioner as part of the certification of precinct boundaries required by section 49.7.