On a sweltering Friday afternoon in Chicago earlier this month, I was in desperate search of relief from the heat. The single air-conditioning unit in my third-floor apartment bedroom was not cutting it: I needed to submerge my body in cold water, fast.

I could have hauled it over to Lake Michigan, but biking for forty minutes in more than 100 degrees was inadvisable. Luckily, just a few blocks from my apartment lay an anodyne oasis: my local public pool.

Within minutes, I walked through the open gate, threw my towel over an unclaimed lounge chair, and hopped into the deep end. My body temperature felt instantly lowered, and I felt grateful for the ability to take advantage of such a vital public good, for free, at just the moment I needed it most.