Heavy storms have caused the Potomac to swell and even spill over its banks in some places.
The U.S. Geological Survey has been monitoring water quality across the Chesapeake Bay watershed, and over 25 years things have gotten a lot better.
"We're seeing less nutrient and sediment in the waterways," says Scott Phillips, Chesapeake Bay coordinator with the USGS.
Phillips says 70 percent of sites showed less nitrogen and phosphorous and 40 percent had less sediment. These are all pollutants that smother life in the Bay.
But stream health is a different matter -- the majority of streams in the region are in "poor" or "very poor" condition based on the health of creatures actually living in them.
"The poorest stream index scores often occuring in highly urbanized watersheds such as those around our primary metropolitan centers," says USGS's Peter Tango.
The "primary" centers are D.C. and Baltimore. The Eastern Shore of Maryland, where there's extensive farming, also had poorer stream quality.Chesapeake Bay Report Card