What’s in the water Washingtonians drink that is linked to obesity, diabetes, autism, cancer, and other disorders—and that medications and products we use every day might contribute to the problem.

Washington’s tap water, most of which comes from the Potomac River, meets or exceeds federal water-quality standards. But new pollutants have emerged that are not removed by current water-purification technology. Evidence suggests that the same contaminants that caused massive fish kills and deformities in recent years are linked to increases in obesity, diabetes, autism, cancer, and other disorders—and that medications and products we use every day might contribute to the problem.

Of all the natural resources in the Washington area, none is more important than the potomac river. Besides the beauty and recreation it provides, the area pulls nearly 400 million gallons of water a day out of it—about 90 percent of our drinking water.

In some ways, the Potomac is cleaner today than it was 40 or 50 years ago. Back then, people were warned not to swim in the river or eat fish from it; a tetanus vaccination was recommended for anyone who did swim there. On many days, you could smell the Potomac before you saw it.

Improvements in wastewater treatment and conservation upgraded the water quality of the river, which wends its way nearly 500 miles from its origin in the Appalachian Plateau to Point Lookout, Maryland, where it empties into the Chesapeake Bay. These efforts helped reduce major pollutants—such as nitrogen and phosphorous from fertilizers, pesticides, and soaps—that fed algae, rootless plant-like organisms that grow in sunlit water. Algae blooms—rapid accumulations of microscopic algae in water that can stretch for miles—deplete the water of oxygen and release harmful toxins. 

They can virtually destroy a river if left to grow unchecked.