What is the drawback of digging a ditch, say 1ft deep, either side of the runway, and having a pump pumping the water out of the ditch to some location say 100m away?
Regarding reinforcement, the place where this is really needed is in the taxiing areas and the part of the runway where one moves slowly. Most planes can get their nosewheel off the ground pretty fast - in the TB20 I can have the nosewheel off after about 100m, even if it needs another 500m after that before one can climb away.