Maps

Fifty-five percent of monitoring sites in the Chesapeake Bay watershed show improving long-term flow-adjusted trends in nitrogen concentrations. Between 1985 and 2013: five out of nine sites—including the James, Patuxent, Potomac, Rappahannock and Susquehanna rivers—have shown improving trends for nitrogen concentrations. Two sites—including the Choptank and Pamunkey rivers—have shown degrading trends. Two sites—including the Appomattox and Mattaponi rivers—have shown minor changes that are not statistically significant.

Up until 2013, submerged aquatic vegetation (SAV, also known as bay grasses) acreage totals for the Chesapeake Bay were aggregated into three zones: Upper Bay, Middle Bay and Lower Bay. For 2013, it was decided to report the totals by the four salinity zones found in the Bay: tidal fresh, oligohaline, mesohaline and polyhaline. Since different species of SAV are generally found in waters of a specific range of salinity, tracking changes in SAV abundance by salinity could help track changes in species abundance more easily.

This map shows the locations of riparian forest buffer restoration projects throughout the Chesapeake Bay Watershed. Project locations were provided by Forestry Workgroup representatives from the Maryland Department of Natural Resources, the Virginia Department of Forestry, the Pennsylvania Department of Conservation and Natural Resources, the West Virginia Division of Forestry, the Delaware Department of Natural Resources and Environmental Control and the Upper Susquehanna Coalition.

This map shows progress toward achieving the Chesapeake Bay Program segment-specific underwater bay grass restoration goals. It is based on the single best year of acreage as observed through the most recent three years of data from the Chesapeake Bay underwater bay grasses aerial survey.

Fish passage is a key component to the restoration of anadromous fish (shad and river herring) in the Chesapeake Bay watershed. These fish are blocked from much of their historic spawning areas, which included waters over 200 miles from the Bay. Maryland, Virginia, Pennsylvania and the District of Columbia have set goals to provide fish passage to make much of those historic spawning areas once again accessible to migratory fish. Other species that benefit from the unblocking of streams include eels, native species such as brook trout and other resident species.

American shad were once the most abundant and economically important species in the Chesapeake Bay. Shad are anadromous fish and spend most of their lives in the ocean, returning to freshwater rivers to spawn after they reach maturity. Data for the York, Potomac, Rappahannock and lower James Rivers were provided by the Virginia Institute of Marine Science via an ongoing Catch per Unit Effort (CPUE) study involving American Shad gill-netting. Data for the Susquehanna and upper James Rivers represent published fishway passage values for Conowingo and Boshers Dams, respectively.

Watershed Yield: Sediment yields ranged from 9.3 to 648 tons per square mile. Each of the 17 sites in the high yield category carries more than 200 tons of sediment per square mile of watershed. High yielding sites are spatially dispersed across the Susquehanna, Potomac and Rappahannock watersheds. The lowest sediment yielding sits are located on the Eastern Shore and the York River Basin.

Watershed Yield: Total Phosphorus yields ranged from 0.036 to 0.57 tons per square mile. Each of the 17 sites in the high yield category carries more than 0.19 tons of phosphorus per square mile of watershed. High yielding sites were found in the Eastern Shore, Susquehanna, Potomac, and Rappahannock Watersheds. The lowest yields are generally in the western areas of the Bay watershed and the York River Basin.

Watershed Yield: Total Nitrogen yields ranged from 0.33 to 9.87 tons per square mile. Each of the 17 sites in the high yield category carries more than 3.4 tons of nitrogen per square mile of watershed. These sites are generally located on the Eastern Shore, Lower Susquehanna and Northern Potomac Watersheds. The lowest yields, which are less than 1.2 tons per square mile, are generally in the Upper Potomac and Southern Virginia Rivers.

Short Term Trend: Over the past 10 years, 49 percent of sites show little change while 41 percent show degrading flow-adjusted sediment concentrations. Between 2003 and 2012: - 4 out of 39 sites show improving flow-adjusted trends for sediment concentrations, - 16 site shows degrading trends, and - 19 sites show small changes that are not statistically significant.