The rain returned to the Bay Area this week, which was a glorious relief after our alarmingly dry January. The dingy air that has hung like a dirty film over everything blew away with the storm, and the sky has been crystal clear.

What isn’t crystal clear is whether we should be swimming when it rains. The typical advice is to wait 48 hours after a first big rain before getting back into the open water. Pollutants that accumulate on our streets and sidewalks, cars and houses, get washed away in the rain, run from gutters into storm drains, and into our bay. Dog poop, car oil, household chemicals, fertilizer, trash, are just some of the sludge that we might be swimming in. As gross as this sounds, staying out never seems like the straightforward right thing to do. For one thing, there always seems to be room to convince myself it’s not that bad. It didn’t rain that much. It’s not really our first big rain. Was it even a big rain? 

The problem is that the benefits of wild swimming are so immense that the risks are easy to overlook. There isn’t anything that gives me as immediate a mental health boost as swimming in the bay. Now that I’m not swimming every day, I’m more aware of this than ever. The days I swim are better in every way than the days I don’t. Swimming shoots vitality and goodness into my cells; I’m nicer to the people around me, and I’m better able to cope with daily challenges. So, in my personal assessment of risk, it’s easy to overestimate the good and underestimate the bad.

This question of risk assessment is something I thought about a lot back when I was in academia. I must have consumed and produced tens of thousands of words on the subject, but it all pretty much boiled down to this: people experience risk in ways that are shaped by, and make sense in, the context of their own lives. Accepting or avoiding risk is an emotional experience as much as it is a rational decision. 

For me this week, the risk from the pollution and bacteria that can run from the streets into the bay after a rain did not seem big enough to outweigh the benefit to my mental health of getting into the water. 

Lucky for me, many swimming buddies agreed. In a nod to safety, we decided to swim heads up. But on the way back, it was so windy and splashy that we were getting our faces full of water anyway and just decided to swim.

The rain is supposed to return this weekend, so I guess we will be asking ourselves these same questions again in a couple of days.