Posted on August 1, 2022
One of the more noticeable features of the Rappahannock River downstream of the Fall Line (Route 1 bridge) in late summer Fredericksburg is the accumulation of silt and other sediment. This shoaling below the Fall Line can be deleterious, as fish eggs and other aquatic life are smothered. In addition, this shoaling can be unsightly and is a hindrance to motorized boats.
Some background and history is needed to understand this problem. The upper Rappahannock west of the Fall Line is a lotic aquatic system, or fast-moving body of water that descends from higher elevations in the Piedmont of Virginia. When the waters and sediment of the upper Rappahannock River reach the slower-moving estuarine, or tidal waters below the Fall Line at Fredericksburg, the sediment tends to fall out or settle on the river bottom. The river below the Fall Line is also wide, which facilitates this dropping of sediment load, often for several miles downstream of Fredericksburg.