Pollution remains a major threat to the Potomac River, its tributaries and the Chesapeake Bay where it flows.
the Potomac Conservancy,
Please select the location that you were searching for from the list below.
Please try searching again using a valid zip code or city and state.
Dr Craig Richard, Shenandoah University: Science behind the "whisper video"
Copyright © 2014 by WTOP. All rights reserved.