Water supplies in the Southwest are limited but Lake Michigan holds a lot of water communities in the Chicago region can access:

Lake Michigan holds more than 1 quadrillion gallons of water, so supply will never be a problem for the region.

Should we be so confident about this? Lake Michigan is large and the Great Lakes contain roughly one-fifth of “the world’s supply of surface fresh water.“

Sure, the Chicago region has limited population increases. The Midwest at large is not exactly growing like the Sunbelt. But, lots of people and governments rely on this water and climates and ecosystems change.

The context for this quote is a dispute between local governments in the region about obtaining water. Hundreds of millions of dollars, perhaps billions, are on the line. People need water. For now, it is there and it probably will be there for a long time…but it is not guaranteed to be there.