Are the Washington City Canal and Champlain Canal both still fully operational ?
Washington City Canal The Washington City Canal operated from 1815 until the mid-1850s in Washington, D.C. The canal connected the Anacostia River, called the "Eastern Branch" at that time, to Tiber Creek, the Potomac River, and later the Chesapeake and Ohio Canal (C&O). The canal fell into disuse in the late 19th century and the city government covered over or filled in various sections.
St. Clair Tunnel The St. Clair Tunnel is the name for two separate rail tunnels which were built under the St. Clair River between Sarnia, Ontario and Port Huron, Michigan. It was the first full-size subaqueous tunnel built in North America. (By full-size it is meant that it allowed a railroad to run through it.) It is a National Historic Landmark of the United States, and has been designated a civil engineering landmark by both US and Canadian engineering bodies.