It was very dry here, in East Tennessee, until the January rains came in. I purchased four rain barrels in June and the rain water they saved was of great value to plants who were practically on their last leg, errr root! My barrels hold 60 gal. each and after even a little shower, they would be full to the brim. I certainly recommend rain barrels to all gardeners, because one never knows just when that next rain event will occur.
Janet, I mostly hand water with my barrels or do the bucket brigade. However, you can purchase a submersible sump pump to spew water out...FAST.
You can raise barrels VERY high, on several tiers of cement block or make a wooden stand and let gravity work in soaker hoses (short runs, this won't create pressure for a long run of soaker hoses).
Kids love dipping or filling buckets and distributing water on a hot day. If you have plants that need a long, slow soak (say a tomato) you can make your own waterer by inverting a soda bottle with no lid (or small holes in the lid) and cutting off the bottom to fill.