The project is headed by Dr. Mariano Ospina of Colombia. Harvard, MIT and the Japanese government are also involved. It is a mega project which should have a large and defining effect on South America when fully implemented.
I looked on the web for a map that showed more relief and found this one. This map is from the Perry-Castenada Library Map Collection of the University of Texas.
The Orinoco River comes close to the Rio Negro which empties in the Amazon. Another tributary, the Rio Madeira, goes down through Bolivia and is some distance from the Rio Parana which goes to Buenos Aires! It looks possible. Those in the know with better maps have better routes I'm sure. When I find them, I will put them on here.
Senor Moreno has sent me two pictures of the South American River System Project. The first is a map showing the river system.
The towns are difficult to read so I will list them here.
From the Pacific Ocean to the confluence of the rivers: Tumaco Colombia and Leticia Colombia
From the Atlantic Ocean to the confluence of the rivers: Ciudad Bolivar Venezuela, Puerto Carrena Colombia and Manaus Brazil *
Going south from confluence: Porto Velho *, Guajara Mirim Brazil *, Cuiba Brazil *, Asuncion Paraguay * and Buenos Aires Argentina *
The asterisks show the ones that are on the relief map above.