Like what jonv112 said, you don't want to drain. As the rain is starting to come back, the water table is probably going to get high quickly.

If you're draining because you're going to redo your pool, then that's different as you can have pressure relief holes drilled so your pool's concrete doesn't get cracked and the whole pool doesn't float.

Nonetheless, the answer to your original question is that a simple sump pump can empty out a pool just fine (but it may take more than a day) and you'd have to know the regulations in your area as draining water has to be done properly, too.