August 10th, 2014



"Today, approximately 175 million tons of polluted sediment sits trapped behind the Conowingo hydroelectric power dam in northeastern Maryland, a product of nearly a century of build-up from clay, silt, fertilizer runoff, and sewage plant runoff from Pennsylvania and New York. The sediment — enough to fill about 80 football stadiums — contains phosphorus, nitrogen, and other harmful nutrients that can cloud waters, sprout toxic algae bacteria, harm ecosystems, kill aquatic life, and sully drinking water. Since 1929, the Conowingo Dam has been collecting that pollution and largely preventing it from entering the Chespeake Bay. But now, that polluted sediment has nearly reached the brim of the dam, and MacLeod worries that just one big storm event could send it over the edge, blanketing and destroying the Bay."