When a city starts running short of water, the obvious question is: Where can we find more? A new reservoir? Groundwater? Desalination? But there is another question that doesn't always get asked first: What are we doing with the water we already have? Corpus Christi, Texas, is providing an interesting real-world example right now. The South Texas city has been dealing with years of drought and growing water demand. Recent rainfall has improved reservoir levels, but the city'