American Canals has some 1998 photos and then additonal photos posted April 27, 2013, that shows the flood damage.
Paul Braun has made a panoramic shot that is well worth the mouse click. It includes the overflow waterfall. And Joe Balynas has another nice shot including the waterfall. Some of his other canal pictures are also quite artistic. Steve Conro has several photos including the sluice gates that control the spillway and the original wooden version. And Skip Maskeri got some pictures of this and other I&M Canal spots during the flood.