On the receipt of an application from any public agency for the authorization of a regional project the district may cause an independent evaluation to be made of the plan submitted and if the district shall find and determine that the project is feasible and is in the public interest, then the district in its discretion may approve such plan as submitted or may approve such plan, subject to such changes and modifications as may be required by the district, or may disapprove such plan in its entirety, all in the discretion of the district. All costs of any consultants, technical or other personnel employed by the district in making an evaluation of such proposed project shall be borne by the public agency submitting the project, but the cost thereof shall be fixed by agreement between the district and such public agency prior to the district undertaking such evaluation. Any such project may, at the request of a public agency, be undertaken by the district for and on behalf of such public agency, subject to such terms, conditions and agreements as may be made by and between the district and such public agency, which agreements shall be binding on all parties thereto, and shall be enforceable in the chancery court as provided in Section 17-11-55. No such project shall be approved without the consent of the governing authorities of each city or county participating in such project and the consent of the governing authorities of each city or county within whose boundaries such project is to apply.