triathlon nontraditional- If one were to set up a half triathlon what would the kakak distance be.?

I have this discussion with a buddy about doing a non swimming half ironman distance triathlon. It would have of course a 56 mile bike ride, 13.1 run but start off with a flat water kakak, instead of the 1.2 mile swim. What would be an equivalent distance to that swim? Has anybody done a tri with a canoe or kakak leg?

AuSable River Canoe Marathon Intro

The entire video covers the entire 120 mile race, which starts in Grayling, MI at 9 PM, and finishes in Oscoda, MI the following afternoon. The 2005 marathon boasted the closest finish in the race’s 58-year history, with legendary paddlers Serge Corbin & Jeff Kolka, edging out last years champion Andy Triebold and his partner Matt Rimer, by a mere second.

marathon racing

flat water canoe and kayack racing an olympic sport eddited and partially filmed by andrew daniels with some voutage from anna hemmings website.