Water can short something out that would cause more voltage to be applied and burn that device out. Water will most certainly cause corrosion that will open up circuits. Water just does not mix well with electrical or electronics at all. If you get a leak, remove to a dry location and dry it out as fast as possible without causing more damage. Seal the leak once your sure that everything is dry. I also like to be proactive and in the case of my kit controllers. Once I have them built and have cleaned off the rosin on the back of the board and have taped off any connections and the socketed chi