Underwater robotics expert reveals 'shipwreck city' hiding beneath major urban lake

An underwater robotics specialist, Phil Parisi, is documenting nearly 100 targets in Lake Union, a central lake in Seattle, Washington, with about half believed to be shipwrecks. The expert uses remotely operated vehicles to document the targets identified in sonar surveys. The lake has served as a working waterway for over a century, supporting shipbuilding and vessel traffic.