Maps

Long-Term Flow-Adjusted Trends for Total Phosphorus (32 Sites in the Chesapeake Bay Watershed) 1985-2009

This map shows the long-term flow-adjusted trends for total nitrogen at 32 Sites in the Chesapeake Bay Watershed from 1985-2009.

Over the past 10 years, sediment concentration trends show mixed responses among the monitoring sites with the majority of results being not significant, 5 sites indicate improving conditions while 6 sites indicate degrading conditions. The trend results indicate that in some locations, management actions, such as erosion and runoff controls may have contributed to reducing sediment concentrations in streams. The short-term flow-adjusted trends and yields indicator is calculated, and results and maps are published annually by the U.S. Geological Survey as part of a larger effort to determine loads and trends in nutrient and sediment concentrations and streamflow in the Chesapeake Bay watershed.

Over the past 10 years, phosphorus concentration trends are not significant at more than half (19 of 33) monitoring sites within the Bay watershed. Improving trends were estimated at 10 sites while degrading conditions were reported at 4 sites, indicating that in some locations, management actions, such as improved wastewater treatment and nonpoint-source pollution controls (i.e. urban stormwater runoff and agricultural runoff controls), have reduced phosphorus concentrations in streams. The short-term flow-adjusted trends and yields indicator is calculated, and results and maps are published annually by the U.S. Geological Survey as part of a larger effort to determine loads and trends in nutrient and sediment concentrations and streamflow in the Chesapeake Bay watershed.

Over the past 10 years, nitrogen concentration trends are downward at about half (16 out of 33) monitoring sites within the Bay watershed. The trend results indicate that in many locations, management actions, such as improved wastewater treatment and nonpoint-source pollution controls (i.e. urban stormwater runoff and agricultural runoff controls), have reduced nitrogen concentrations in streams. In addition, in the last 5 years, higher yields indicate a tendency to be located in the northern half of the watershed, conversely. lower yields are more numerous in the lower half of the watershed. The short-term flow-adjusted trends and yields indicator is calculated, and results and maps are published annually by the U.S. Geological Survey as part of a larger effort to determine loads and trends in nutrient and sediment concentrations and streamflow in the Chesapeake Bay watershed.

The 2011 Chlorophyll a percent of goal achievement by CBP segment.

This map shows the percent of the Water Clarity goal achieved for each Chesapeake Bay Segment in 2011.

The 2011 Dissolved Oxygen Indicator showing Percent of Goal Achieved using the three year analysis method.

This map shows population estimates within the Chesapeake Bay watershed on a county-by-county basis for the year 2010. These are actual Census Bureau population figures provided after the last decennial census (2010). However, for counties not completely within the Chesapeake Bay watershed, the population numbers were derived as a proportion of the total county based on land area.

This map displays the segmentsheds used by the Chesapeake Bay Program. A segmentshed is the discrete land area that drains into each of the 92 Bay Program segments (see map of Chesapeake Bay Segmentation Scheme) that have TMDLs associated with them.