Another problem is that much of the of the most productive farm land (around Taylor, Hutto, Elgin, etc.) is now covered with homes. Subdivisions are going up everywhere within the 50 miles east of Austin.
My wife and I were living just a few miles west of the San Antonio city line in 2006. Water use restrictions were the norm. Evey time it rained was a news event and the aquifers were monitored every day on TV and the news paper.