Waterfalls in the Bathroom

My dearest, sweetest, oldest child is incredibly creative. The other day Eli said he wanted to take a bath/shower. He has been taking bath/showers on his own for about 6 months now, and until this time had done a great job keeping the water in the tub, only a few minor spills here or there. (You can see where this is going, can't you). He also takes REALLY long showers, he likes to let the water run over him and he of course likes to play with the bath toys, so if he is in there for 10-20 minutes I usually don't concern myself. Well this particular day, I was doing a lot of packing and my mind was on the millions of things I needed to do before we moved...So there is my disclaimer. Anyway to the story...So Eli is taking is usually long shower/bath and after about 20 minutes comes out, and proudly exclaims "WOW, that was fun!" It was then I noticed that the bottom of his towel was sopping wet, but not enough to raise any red flags in my mind. So me being an attentive mom (well some of the time) asked him "what was fun". He then proceeds to tell me the following: " I made waterfalls in the bathroom, and I learned how to swim." Now the red flag is FLASHING and WAVING FRANTICALLY!!!! So I then ask Eli what he means by waterfalls and if there is water on the floor in the bathroom. He then says in a calm but reassuring manner "Yeah there is water on the floor". Of course I rush to the bathroom to find about 2 inches of water on the floor, now I know what he meant when he said waterfalls. Apparently he realized that if you pull the plug up to make a bath and keep the water going then the bathtub can then fill up with water and overflow down the sides, thus creating a waterfall effect, how fun and ingenuitive of him! I was able to soak up all the water using the recently washed towels that I hadn't packed yet, and borrowing some from our neighbors. Boy what an adventure!