If a railroad and road authority enter into an agreement or if the department orders or otherwise authorizes the construction, relocation, or improvement of a railroad crossing at grade, the construction of a grade separation structure, the reconstruction of an existing grade separation, the alteration of existing grade separations for increased highway or railroad facilities, or the establishment of a clear vision area, the right-of-way and other property rights necessary for the project, unless otherwise agreed upon, shall be acquired by condemnation in the same manner as property is acquired for other highway purposes.