The scenic rivers around Annapolis, where generations of Marylanders have crabbed and fished, are among the most polluted in the state, researchers said yesterday.
The second annual Chesapeake Bay Report Card gave its lowest grades to the collection of rivers that flow through Anne Arundel County - the Severn, the South, the Magothy, the Rhode and the West - as well as to Southern Maryland's Patuxent River. Researchers from the University of Maryland Center for Environmental Science, who gather data on the rivers, gave each a D-minus.
Adding to the dismal news yesterday was the annual Health and Restoration Assessment published by the Chesapeake Bay Program, a multistate government agency charged with cleaning up the bay. It found that the water in nearly 88 percent of the bay and its tributaries does not have enough oxygen in summer to sustain marine life.
"There are some positive signs, and much good work that has been done, but what our reports tell us is that the bay is degraded and in a vulnerable state," said Jeffrey Lape, director of the Chesapeake Bay Program.
On the Chesapeake Bay Report Card, the bay's overall grade improved slightly, from a D-plus in 2006 to a C-minus for 2007 - improvement attributed largely to weather. Drought last summer reduced pollution from runoff.
The only real success stories were north of Baltimore - the Bush, Gunpowder and Middle rivers each received a B, up from D-plus - and the Choptank, which was second-worst on the list in 2006 but was in the middle of the pack for 2007.
William Dennison, the university vice president who oversees the report card, said he expected the bay and the rivers to have a better year, particularly because of last summer's lack of rain. He said the bay seems to still be recovering from 2003, an unusually wet year that was made even worse by Tropical Storm Isabel.
The main causes of bay pollution have long been known - runoff from fields and paved areas, nitrogen from sewage treatment plants, and sediment from erosion. Dennison said the report's data bolster the connection between land and water, and that he hopes the research will guide local officials in land-use decisions.
"We've explicitly linked land use within the tributaries to bay health, and that links more strongly the fact that we need to resolve our problems with actions on the land," Dennison said.
