As soon as practicable after the organization of any such district, the board of directors shall, by a resolution entered on its record, formulate a general plan of its proposed operation in which it shall state (1) what constructed works or other property it proposes to purchase and the cost of purchasing the same and (2) what construction work it proposes to do and how it proposes to raise the funds for carrying out such plan. For the purpose of ascertaining the cost of any such construction work, the board shall cause such surveys, examinations, and plans to be made as will demonstrate the practicability of such plan and furnish the proper basis for an estimate of the costs of carrying out the same. All such surveys, examinations, maps, plans, and estimates shall be made under the direction of a competent irrigation engineer and certified by the engineer. The board shall then submit a copy of the same to the Director of Natural Resources within ninety days thereafter, who shall file a report upon the same with the board, which report shall contain such matters as in the judgment of the director may be desirable.