The Rappahannock River Watershed
The Rappahannock River stretches 184 miles from the Blue Ridge Mountains to the Chesapeake Bay, starting out running over the rolling hills and then moving down into flatter country (pictures of upper, middle, lower basin). Below Fredericksburg the water is brackish, supporting the crab and oyster industry. The Rappahannock Watershed covers about 2,848 square miles, 6% of the state (picture). The watershed is comprised of many different land uses, 55% of which are forested, 38% agriculture, and 7% Urban. Between 1982 and 1997 there was a net loss of approximately 14,300 acres or a 4% decrease in cropland, pasture land shows a 13% loss, and forest land a 3% loss. The majority of this land is being converted to developed land, resulting in a 60% increase from 1982-1997.
Although the Rappahannock has historically been considered one of the nations most pristine rivers, it is now facing many problems. Water quality monitoring throughout the Rappahannock has indicated that there are increased nutrient and sediment loads entering the river and its tributaries. Increases in these pollutants have caused a decrease in dissolved oxygen, and an increase in algal blooms, submerged aquatic grasses, and suspended solids.
There are several possible causes of the increased problems. The conversion of pasture, crop, and forest land to urban has increased the amount on impermeable surfaces in the watershed. Impermeable surfaces, such as roads, do not allow water to filter through; instead the water runs off and enters the river and its tributaries at a much higher rate. With the urban areas also comes an increase in homes where people want nice green lawns. However, in the effort to have the greenest lawn in the neighborhood, homeowners often inadvertently over fertilize. The grass is unable to use all the nutrients, and it has to go somewhere, so it runs off their land and eventually makes its way to the Rappahannock. Talk with your neighbors about lawn fertilization. Local extension offices can help you to make informed decisions on the amount and type of fertilizers needed by your lawn.