I like Justins idea, I think that would work great.  The NM game and fish dept. builds what they call "trick tanks" in areas with low natural water sources.  They consist of a plastic or metal gathering/holding tank which feeds a small (3-4ft diameter, maybe a foot deep) depression in the dirt lined with concrete.  
I think its use could depend on the severity of the drought.  Obviously the desert southwest is a little different than Alabama, but when times get lean here, water is water.  Once a source is located, it is used with regularity, even if the animals have to lower their standards a little.