Funds shall be expended and contributions made to a political subdivision of the state from flood control appropriations only after:
(1) The project for which the funds are to be used has been approved by the department of ecology in accordance with the regulatory provisions of chapter
86.16 RCW.
(2) Engineering studies and plans have been made and filed with the county engineer of the county in which the project is located, or the county engineers of all counties in which the project is located, if it is located in more than one county.
(3) The estimate of cost of acquisition of necessary lands, rights-of-way and construction of the project or improvements, together with adequate supporting data have been completed and filed with the department of ecology.
(4) A comprehensive plan for the area involved has been completed and filed with the department.
(5) The political subdivision desiring a contribution has made an application for a contribution to the department showing the estimated cost of the project and the requested contribution.
(6) Federal funds are available for contribution for payment of a portion of the cost of the project.
The director of ecology is authorized to determine when these conditions have been met and to request the proper warrant for the state's contribution. Contributions to a political subdivision for a specific project shall not exceed fifty percent of the cost of acquisition of necessary lands and rights-of-way, and construction of the project or works of improvement.