(1) "Federal agency" includes the United States, the President of the United States, and any agency or instrumentality of the United States which is designated, granted or authorized to engage in the building, construction and maintaining of flood control projects on any lakes, rivers or streams within Oregon.
(2) "Board of commissioners" means the governing body of any county in the state, whether the same consists of two county commissioners and the county judge or three commissioners.
(3) "Contract" includes contracts and agreements in the customary form; also a commitment by a federal agency by which it undertakes to make or engage in the construction of works for the purpose of controlling floods, and the terms, conditions and restrictions therein set forth.
(4) "Flood control project" means any plan, system, manner or means for the control, diversion, conservation or abatement of floodwaters or any excessive or unusual accumulation of water in any natural or artificial stream or body of water, or for protection of life and property against danger, menace, injury or damage resulting therefrom.