I'm still not convinced that it would be a wise strategy. He would have to leave himself open to attack to do this. Or at least find a way to buy himself time. He is known for being very fast, so if an opening is created that would give him time.
Actually, the Jedi Apprentice books indicate otherwise, specifically book 7.
If the pipes are in the walls, chances are they would not be that hard to get to, in case of a pipe bursting, they would want to be able to get to said pipe fairly quickly so they don't start having a mold problem...
All Fisto has to do is spray Kolar and his saber with a lot of water, which would be fairly easy to do. The place doesn't need to partially submerged in order for him to short out a lightsaber.
Come on people don't tell me none of you have ever handled garden hoses before...
(Just thinking out loud here)We know that Kit Fisto preaches restraint, but then I think he would give a good Force Push to Kolar if he had to. Heck, he could even use Kolar's tendency to suddenly use Force Push to do this. But then there's the issue of Kolar making a quick follow up.
It would probably fall to Fisto to create a gap.