Iowa Code § 6B.52: Renegotiation of damages.

Whenever property or an interest therein has been taken by condemnation or has been purchased for a public use and a settlement for construction or maintenance damages has been thereafter entered into pursuant to said condemnation or purchase, the owner shall have five years from the date of said settlement to renegotiate construction or maintenance damages not apparent at the time of said settlement. The condemner or purchaser shall give written notice to the owner of such right of renegotiation at the time said settlement is entered into.