Some people may be familiar with it — the smell of rainwater in a covered tube. It's a stale, unpleasant smell. And it's similar to what happens at the Chesapeake Bay every summer.
Fertilizer washes into the Bay from farms, septic tanks, sewage plants, and backyards. Then algae eat it and make giant algae blooms so big they can be seen from space.
The algae die and rot. After that, the unpleasant smell of low oxygen water is produced. This toxicity in the water is huge, and it kills tens of thousands of animals in the Bay every year.
Bill Dennison, a scientist with the University of Maryland, says how bad it gets next summer, depends on this spring.
"The big thing is in setting things up right now, and the precipitation between now and April," he says.
That's because the rain is what washes all the fertilizer into the Bay. But the rain also sends a sheet of freshwater that floats on top of the saltier water, deeper in the Bay, kind of like a lid, sealing the nasty water down below.
"The double whammy of injecting nutrients, and you're also trapping the bottom water from the surface," Dennison says.
Over the long term he says, programs to reduce the nutrients that flow into the Bay are working, but from year to year, the spring rain has a big say.