Was Duluth Ship Canal or Cross Florida Barge Canal cancelled for environmental reasons?
Duluth Ship Canal:  Begun privately in 1871, it was put under federal supervision and maintenance several years later. Cross Florida Barge Canal: The Cross Florida Barge Canal, now officially the Marjorie Harris Carr Cross Florida Greenway is a protected green belt corridor, one mile (1.6 km) wide in most places.
i don't know