JANESVILLE -- Flood waters in Rock County have turned some streets into a virtual aquarium.

That 's because hundreds of fish were in the waters of the Rock River when it spilled over containment walls in downtown Janesville.

The north end of Main Street is underwater, and the fish are easily visible below the surface.

State biologists say most of the fish are carp.

Wildlife officials say they 're worried that the fish can get stuck outside the river if the water recedes too quickly.

Rock County deputies are more worried about the curiosity factor. They say the fish are increasingly attracting gawkers, but authorities are trying to keep people away from flood waters that can be contaminated with sewage and other chemicals.