Your analogy isn't a very accurate representation of the problem some communities in Iowa are facing. Instead of an empty glass fill it to the top with sand so only a small percentage of the water you try to put into the glass infiltrates and the rest runs off. Then punch a couple of straws into the sand that people are continuously drinking out of. A little more accurate representation there.While it might take a week for a 16 ounce glass of water to evaporate in the summer sun........it only takes a few seconds to fill it up.
Northern Texas in 2015 and California last winter are a testament to that after many seasons of below average rainfall.......just one with above average worked wonders.
Things in Iowa the summer of 92' were pretty dry....................12 months later?
Who knows what will happen this spring in Iowa.
