The contracts with other public agencies, private corporations, or persons may provide for contributions to be made by each party thereto, for the division and apportionment of the expenses of the acquisitions and operations, and for the division and apportionment of the benefits, the services, and products therefrom. Such contracts may also provide for an agency to effect the acquisitions and to carry on the operations, and shall provide in the powers and methods of procedure for such agency the method by which the agency may contract. Such contracts may contain such other and further covenants and agreements as may be necessary or convenient to accomplish the purposes thereof.