Footage of them being pulled out of the river at link:
http://www.msn.com/en-us/video/watch/150-year-old-confederate-cannons-found-in-river/vi-AAeWFMv
http://www.msn.com/en-us/video/watch/150-year-old-confederate-cannons-found-in-river/vi-AAeWFMv