Whenever it shall be deemed necessary by an authority, in connection with the exercise of its powers herein conferred, to take or acquire any lands, structures or buildings or other rights, either in fee or as easements, for the purposes herein set forth, the authority may purchase the same directly or through its agents from the owner or owners thereof, or failing to agree with the owner or owners thereof, the authority may exercise the power of eminent domain in the manner provided for condemnation proceedings in Chapter 54 of this code, and such purposes are hereby declared to be public uses for which private property may be taken or damaged.