Standing in Chicago, Illinois, and gazing across the vastness of Lake Michigan, it is hard to imagine that communities in the surrounding region could be concerned about running short of water. However, international treaties, U.S. Supreme Court decrees, and interstate agreements restrict diversions of water from the Great Lakes in an effort to maintain lake levels. This forces the region to use alternative sources of water to serve the rapidly growing population. Local governments in the southern Lake Michigan region, and likely elsewhere in the Lake Michigan region, need to acquire and integrate data and information regarding the region's water supply into planning processes.