Traveling water screens, or bandscreens, are automatically cleaned screening devices that are used to remove floating or suspended debris from a channel of flowing water. Traveling water screens consist of a continuous series of wire mesh panels bolted to basket frames, or trays, and attached to two matched strands of roller chain. Thru flow traveling water screens, also referred to as "direct," "single," or "uni" flow screens, are the most common type of raw water intake screen in the United States. Dual flow traveling water screens were developed in the 1920s and have been used extensively in Europe and Asia and are being applied on an increasingly frequent basis in the United States. The center flow screen is a variation of the dual flow traveling water screen that has a single entry/double-exit flow pattern. Double-entry dual flow screens can be mounted from a platform or pier that is supported by pilings, eliminating the need for a concrete channel or well.