Headwaters to Baywaters

Headwaters to Baywaters. . , An intricate network of streams, the Occoquan Watershed drains 590 square miles around you. To the northwest, the forested Bull Run Mountains are the source, or headwaters of the watershed, which begins as three small, spring-fed streams. These streams are joined by other streams, eventually forming Bull Run., Bull Run meets the Occoquan River about 10 miles downstream from here. The river then fills the Occoquan Reservoir, a source of drinking water for over 1 million Northern Virginians. Though mostly impounded by a dam, some water still continues to journey below the dam, the fresh water mixes with salty tidal water of the Potomac River before flowing to the Chesapeake Bay., While Bull Run's journey to the Bay is shaped by the mountains, valleys and tidal plains, forests define its health. Foreste protect water, filtering our pollutants and holding soil in place. Keeping or planting trees, shrubs and groundcover helps provide the vegetation that keeps water healthy., Conservation Through Understanding , Harry Ardell Allard, an internationally known botanist, discovered how the duration of light and darkness affects the flowering and germination of plants. Allard loved the Bull Run Mountains, and in 1930s and '40s, he made 55 trips a year to this region, collecting nearly 15,000 plant specimens and describing their habitat. Today's efforts to protect and restore this watershed still rely on images from Allard's field notes.