If the Potomac River has gotten more attention than the Anacostia in the past 50 years, it’s partly because the Potomac supplies 90 percent of the region’s drinking water. That amounts to an ...

Although swimming is illegal along parts of the District of Columbia, the Potomac River is probably clean enough for swimmers during the driest stretches of the year, when water pollution is lowest.

In the 1960s, the Potomac River was declared a “national disgrace” by President Lyndon B. Johnson. Decades later, the condition of the river has earned a “B” from the Potomac River ...