(a)
(1) After their qualification, the board shall form plans for the improvements within the consolidated district.
(2) These plans shall include the existing water plant and system and the existing light plant and system owned and constructed by the separate water and light districts. The plans shall also include such additions, extensions, enlargements, improvements, repairs, and replacements thereof and thereto which the board may determine upon.
(3) As soon as the plans shall have been determined upon, the board shall file a copy of the plans and an estimate of the cost thereof with the city council. The copy of plans so filed shall show the character and extent of the plans and systems acquired or constructed by the separate light and water districts, as well as all new proposed improvements to be made for the purpose of consolidating the operation of the plants and all other new proposed improvements and extensions to the existing plants and systems. This copy shall also show the location of all water mains including such extensions and new mains as are proposed and shall show the location of all electric light and power lines including such extensions and new lines as are proposed.
(4) The estimate of the cost shall include all sums required to pay for the existing system as well as the cost of new improvements and extensions.
(b) At any time after the filing of the original plans provided for in this section, the board of improvement of such a consolidated district may, upon the request of the city council of the city in which such district is located, form additional plans for new improvements, extensions, repairs, or replacements to the consolidated water and electric light plant and system. A copy of the plans and of the estimated cost thereof shall be filed with the city council.