Except when otherwise provided for by contract, permit or ordinance, a unit of local government having jurisdiction over streets or roads may repair damage to any such streets or roads caused by a public or private utility and bill the utility for the cost thereof if the utility fails to complete such repairs within 30 days after receipt of written notice from the unit of local government that such repairs must be made. Primary responsibility for such repairs shall remain with the utility.
     As used in this Section, “unit of local government” means a county, municipality, township or other unit designated as a unit of local government by law.