Timber harvesting, increases in agricultural and urban lands, and the lack of protective environmental practices have led to excess sediment and nutrients washed into the Bay. When sediment, which is composed of loose particles of clay, silt, and sand, becomes suspended, it makes the water cloudy and reduces the amount of sunlight that reaches the submerged aquatic vegetation (SAV) that provides habitat and stability to the bay. The reduction in water clarity in the Bay has lead to a drastic decline in SAV over the past 30 years and this coupled with poor water quality, leaves the Chesapeake Bay classified as an “impaired water body”.
Implications for restoration of the Chesapeake Bay and its watershed
Both nutrient and sediment reductions will be needed to improve water clarity in the Bay;
Different strategies will be required to reduce sediment since its sources and transport are different from nutrients;
Because of the long travel times for sediment, management actions to reduce sediment in the watershed will help local streams but may take decades or longer to improve water clarity in tidal waters. Therefore management actions for sediment should consider targeting near-shore areas.