Some Bay swim spots like taking a dip in toilet?

On hot days like we've had this summer, I like to think back to the refreshing dips I've taken over the years in the Chesapeake Bay. I'm older, wiser -- and a little disgusted -- to learn now that some beaches and recreation spots around the Bay are about as safe to swim in after a hard rain as an unflushed toilet.

That's what reporters at the University of Maryland found recently when they sampled seven spots on five rivers that feed the Bay.

Three of the seven had bacteria levels that exceeded Maryland and Virginia standards for safe recreation, they reported, while five were higher than the safe level for swimming.  Two - Savage Park in Howard County and Middle Branch Park in Baltimore - had bacteria counts far worse than an unflushed toilet they also sampled.

The water sampling is part of a multimedia report, Bay on the Brink, being produced by the reporters, who are fellows with News21, a consortium of journalism schools. (Full disclosure: I'm a consultant to News21 and advising the fellows in their reporting.)

Sally Hornor, a biology professor at Anne Arundel Community College, analyzed water samples taken by the reporters.  She points out that storm-water pollution is the usual culprit when bacteria counts soar in open waters.  A hard rain washes litter and a host of unseen contaminants - animal waste, food scraps, sewage overflows - off streets and parking lots into storm drains and nearby streams.

There are no official swimming beaches on the Middle Branch of the Patapsco River, and I've never seen anyone taking a dip there.  The city health department advises against swimming anywhere in the harbor or the rivers that feed into it.  But there are crabbers and fishers at Middle Branch park, and the river there is used regularly by members of the Baltimore Rowing Club.

Swimming is off limits at Savage Park on the Middle Patuxent River, too.  But as the photo above shows, it's not enforced, and it's a popular cooling-off spot on hot days.

To be sure, there are officially sanctioned bathing beaches around the Bay, and local health authorities regularly test them.  They're closed when bacteria levels are unsafe - most likely after a heavy rain.   But even if there's no warning sign on the beach, it's a good precaution to stay out of the water for at least several hours after a downpour.

(Photo by Allison Frick, courtesy of News21)