(a) Plans prepared by “local organizations,” as defined by the Watershed Protection and Flood Prevention Act, with assistance from the United States Department of Agriculture, Soil Conservation Service, and plans prepared by the Department of the Army, Chief of Engineers, or any other federal or state agency may be adopted by the board of directors and when so adopted shall become the plan of improvement of the district and may be used in lieu of the engineer's survey and other requirements pertaining thereto mentioned in § 14-117-202, or as a supplement to the preliminary survey and report filed under the provisions of § 14-117-203. As soon as the board has adopted its plan for improvement of the district and has ascertained the cost thereof, it shall file the plan with the chancery or circuit clerk. The plans shall be accompanied by a map showing the location of the proposed improvements.
(b)
(1) If, in the preparation of the final work plan, it is determined by the board that the location and character of the works of improvement are so varied that it would be impracticable to let contracts on all of them in the same year, or if federal funds would not be available for all of them in the same year, the final work plan may be segregated or divided into one (1) or more units of construction constituting any work or group of works proposed in the final work plan which can be constructed and operated as a feasible unit alone and which can also be operated economically in conjunction with the other proposed works in the plan.
(2) The final work plan shall indicate the area included in each unit of construction and establish each such area as a separate construction area, set forth the percentage or portion of the total project costs allocated to each construction area, and delineate the lands in each construction area which, on the basis of preliminary estimates, will derive some benefit from the works of improvement to be installed therein.
(3) Each construction area shall be appropriately identified by name and number, such as “Construction Area No.….”.
(4) The determination of the board that the works of improvement proposed in the final work plan, even though divided into units of construction, do not lack unity or singleness of purpose and that the works in each unit of construction confer some benefit on the lands therein shall be final and conclusive.
(c)
(1) The board of commissioners shall have the authority to let contracts for carrying out the works of improvement on a construction area basis, to borrow money and issue notes or bonds, and to assess benefits and damages on a construction area basis.
(2) A separate assessment book shall be prepared and maintained for each construction area.
(3) The tax levied under § 14-117-413 to secure and repay notes or bonds shall be limited to and be a lien only on the lands located within each construction area found to be benefited by the works installed in the construction area, and that fact shall be indicated on the face of the notes or bonds.
(4) All published notices with respect to the assessment of benefits and damages and the borrowing of money and issuance of notes or bonds shall list the lands according to the construction area in which they are located.