The Nautilus, designed by industrial design students TJ DiTallo and Mara Maxwell at Metropolitan State University of Denver.

(Courtesy the Greenway Foundation)

More than 100 pounds of plastic bottles, 70 pounds of paper, even 62 pounds of discarded clothing. That's how much trash was collected from in and along Denver's South Platte River during annual clean-up events.

Officials from Denver's Department of Environmental Health say a lot of trash flows into urban rivers and streams especially during heavy rain. Recently, the non-profit Greenway Foundation sponsored a competition to design a machine that collects trash in urban rivers so it can be removed more easily. Five teams from Metropolitan State University of Denver took part. The winning machine is called The Nautilus, designed by seniors Mara Maxwell and TJ DiTallo. They spoke with CPR's Nathan Heffel.