St. Marys River

Cascading through one of Virginia's most scenic canyons runs St. Marys River. This breathtaking native brook trout stream has long caught the interest of businessmen, scientists, government, and the public in general. A hike through St. Marys gorge yields both a natural feast for the eyes and a reminder of the days when the area was heavily mined for manganese. In fact, old cables and slabs of concrete are testimony to the heavy mining activity that occurred in the watershed around 1910. A railroad spur was built by the Pulaski Iron Company along St. Marys River up to its confluence with Chimney Branch. St. Marys River was adversely affected by heavy mining through World War I. The stream slowly recovered and scientific investigations began in 1936 with groundbreaking chemical and aquatic macroinvertebrate (bug) work done by Eugene Surber. His findings provided invaluable baseline biological information that is still used by scientists today. St. Marys River was also used as "proving grounds" for a DDT experiment conducted by the federal government in the 1940's. This was a one-time test and no permanent damage was done to the river. The U. S. Congress declared the 10,000 acres in the watershed a wilderness area in 1984.

The Virginia Department of Game and Inland Fisheries' (VDGIF) management activities date back to 1948, when St. Marys River was stocked with catchable brook and rainbow trout. Stocking continued until 1974, after high water washed out the access road along the stream. From that point on, St. Marys has supported populations of native brook trout and naturalized (wild) rainbow trout. DGIF began monitoring fish and macroinvertebrate populations in 1976, and the process continues to this day. The database constructed with the information collected in these biological surveys tells an interesting story about the river, its inhabitants, and man's influence on it.

Part of the puzzle that was missing from the DGIF surveys was good chemical analysis of the water itself. This gap has been filled by DGIF by funding a long-term study with the University of Virginia and citizen volunteers. Since 1987, chemical data has been collected at different points in the watershed and analyzed in the lab. The results show that St. Marys River is an "acidified" stream, as a result of both acid precipitation and the impervious rock that the water flows over. The chemical data helps explain why certain "acid sensitive" fish and bugs have been declining over the decades. In an effort to stem the slide of the stream into biological oblivion, the Forest Service, James Madison University, VDGIF, and other organizations organized a campaign to lime St. Marys watershed to help ameliorate the negative impact of acidification. In March, 1999, St. Marys River and five of its major tributaries were "dosed" with 140 tons of limestone sand. This was done with a helicopter and the sand was applied directly to the stream. This type of liming exercise was tested in other watersheds to great success, so it was reasoned that it would be of some short-term relief to St. Mary River. Chemical and biological monitoring continue to this day and the results are encouraging.