Iowa Code § 820.24: Expenses — how paid.

When the punishment of the crime shall be the confinement of the criminal in the penitentiary, the expenses shall be paid by the department of corrections; and in all other cases they shall be paid out of the county treasury in the county wherein the crime is alleged to have been committed. The expenses shall be the fees paid to the officers of the state on whose governor the requisition is made, and all necessary and actual traveling expenses incurred in returning the prisoner.