growing near swamp in buckets??

hey guys found a decent spot yesterday that im going to try out, next to a swap/pond type deal and gets most of the mourning to mid afternoon sun,first time ever growing in buckets,i have four 5 gallon buckets and a bunch of 3 gallon buckets.the strains im going to grow in the buckets are haze,kc mango,and some very good outdoor weed i bought last yr that had seeds.my question is with the 3 gallon buckets what happens when the plant gets root bound?does it die or just not grow as big,im not worried about the size of the plant i just want some smoke...and on the buckets where should i put the drainage holes?since some of these are near water should i put the holes on bottom of bucket or a few inches from the bottom?