Trash-hunting robotic submarine dives into Chicago River A small, remote-controlled submarine fetching trash in the Chicago River won't be able to clean it up on its own -- after all it only has one claw -- but the contraption is part of a long-term plan to do so, and it's also a gee-whiz way to educate locals about the bigger pollution picture. The sub "is a way to clean up but also to connect people to the underwater world right at their feet so they can see the trash and the creatures and, ultimately, become better stewards of our ocean, lakes and rivers," Rachael Miller told NBC News in describing the robot used by her environmental group, the Rozalia Project. The trash collector has been deployed across the Northeast and this week was in Chicago. The Rozalia Project uses an underwater camera to show locals what's under the water -- in Chicago's case, beer cans, a deck chair and lots of other trash. And while the robot is small, it's claw "can pull out 75 pounds worth of stuff," said Miller. NBCChicago.com A can is retrieved from the Chicago River by the Rachel Project's remote-controlled submarine. This year alone, 420,000 pieces of trash weighing 72 tons have been pulled out of rivers, lakes and seas with the Rozalia Project's help, Miller said. It's not just the sub plucking trash, but surface nets and volunteers on shore. The items are mostly junk like lost fishing gear, but include a few treasures like an 1800s moonshine jug found in Indiana and a Navy ship anchor found in Narragansett Bay in Rhode Island. Next stops for the submarine include Los Angeles, Sacramento, San Diego, San Francisco and Santa Cruz in November. Chicago, for its part, this year embarked on a $10 million cleanup of its river, with help from the state and the federal Environmental Protection Agency. Mayor Rahm Emanuel this week also unveiled plans to expand the city's Riverwalk another six blocks, calling the river the "city's next recreational frontier," NBCChicago.com reported.