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Topic
- West (U.S.) 7
- Bodies of water 4
- River engineering 4
- United States--Appropriations and expenditures 4
- Rivers 3
- Boats and boating 2
- Canals--Design and construction--Costs 2
- Inland navigation 2
- Locks (Hydraulic engineering) 2
- Photography 2
- River surveys 2
- Steamboats 2
- Boatbuilding 1
- Canada, Western 1
- Canals 1
- Cartography 1
- Cascade Range 1
- Dams--Design and construction 1
- Dams--Surveying 1
- Discoveries in geography 1
