I live in Seattle and swim in Puget Sound (or Lake Washington). Recently I've been swimming most often out of Alki beach in West Seattle.
Seattle has a dirty little secret. That is, with each large rain storm, the city releases thousands of gallons of sewage into the waterways, both Puget Sound and Lake Washington. This is done to keep the sewage from backing up into the streets when the storm drains are full. That's, on balance, probably a good idea.
However, I don't especially like swimming in raw sewage. And so, when the rains are heavy, I check the city website for information on if the Combined Sewage Outflows (CSOs) have fired off. If they have, I don't swim.
Here's the chart from this weekend, with my swim point marked with an arrow:
One might argue that the CSOs near my swim site weren't dispensing, so why not swim? Well, I once got VERY sick after a swim with that logic. So these days, a red or yellow CSO means no swim for me.
I hope to be back this weekend. And, as the days are getting (slightly) longer, perhaps an after-work swim will be back on the agenda soon!