Abstract: This invention relates to a method of using sidewalls from discarded automobile, truck, and other tires to manufacture drainage culverts. It also relates to the culverts manufactured by this process, and to assembly devices useful for assembling and holding together such culverts. These culverts are made by means of a simple cutting operation which removes both sidewalls from a discarded tire. The tread portion is made available for any other desired use, and is not further involved herein. The two sidewall portions are laid flat together and drilled with holes which allows them to be mounted on parallel bars which have been welded to a circular steel base plate having roughly the same dimensions as the sidewalls. When a suitable number of sidewalls (such as about 50 to 150) have been mounted on the bars, a steel closure plate having matching holes is slid onto the bars, pressed hard against the sidewalls using a press, and welded to the protruding bars.