• Progress

    During the 2013 to 2015 assessment period, an estimated 37 percent of the Chesapeake Bay and its tidal tributaries met water quality standards. This marks an almost 10 percent increase from the previous assessment period, but is far below the 100 percent attainment needed for clean water and a stable aquatic habitat.

    The Bay and its tidal tributaries can be divided into 92 segments. Each of these segments contains up to five “designated uses” (also known as aquatic habitats), including deep channel, deep water, open water, shallow water and migratory fish, spawning and nursery. In all, the Bay and its tidal tributaries contain 291 designated uses. Each of these designated uses has its own set of criteria for dissolved oxygen, water clarity/underwater grasses and chlorophyll a (a measure of algae growth), which are designed to protect those uses. If the Bay and its tidal tributaries are to function as a healthy ecosystem, all water quality standards or criteria must be met.

    Water quality is influenced by nutrient and sediment loads, which in turn are influenced by river flow. Between October 2014 and September 2015, river flow to the Bay measured a below-average 41 billion gallons per day. During this same time period, approximately 217 million pounds of nitrogen, 9.8 million pounds of phosphorus and 2.9 billion pounds of sediment reached the Bay: a 25 percent, 44 percent and 59 percent drop from the previous year, respectively. Experts attribute this drop in pollution loads to dry weather and below-average river flow, but note local efforts to reduce pollution also played a role.

    In 2016, the USGS released its analysis of the long-term (1985 to 2015) and short-term (2006 to 2015) trends in nutrient and sediment loads at nine River Input Monitoring (RIM) stations. Together, these stations reflect the nutrient and sediment loads delivered to the Bay from 78 percent of its watershed. Long-term and short-term nutrient and sediment trends are summarized in the table below. An upward arrow indicates improving conditions (and downward trends in nutrient or sediment loads), while a downward arrow indicates degrading conditions (and upward trends in nutrient or sediment loads).

    Status of Pollutant Load Trends
    Monitoring Station Long-Term Trend (1985-2015) Ten-Year Trend (2006-2015)
    Susquehanna River (Conowingo, MD)
    Potomac River (Washington, DC)
    James River (Cartersville, VA)
    Rappahannock River (Fredericksburg, VA)
    Appomattox River (Matoaca, VA)
    Pamunkey River (Hanover, VA)
    Mattaponi River (Beulahville, VA)
    Patuxent River (Bowie, MD)
    Choptank River (Greensboro, MD)

    Over the long term, trends in both nitrogen and phosphorus loads have improved at three monitoring sites (including the James, Patuxent and Potomac rivers) and degraded at one (the Choptank). Six sites show long-term improvements in nitrogen loads, while three show long-term improvements in phosphorus loads. Three sites (including the Choptank, Patuxent and Potomac rivers) show long-term improvements in sediment loads.

    Computer-simulated nitrogen, phosphorus and sediment loads (generated using the Chesapeake Bay Program’s Watershed Model (Phase 5.3.2) and wastewater discharge data reported by watershed jurisdictions and calibrated using monitoring data) are used to track progress toward the 2017 and 2025 Watershed Implementation Plans (WIPs) outcome.

  • Management Strategy

    To achieve the water quality standards attainment and monitoring outcome, participating partners have committed to:

    • Analyzing water quality trends in the Chesapeake Bay and its watershed;
    • Explaining the factors affecting water quality trends in the Bay and its watershed;
    • Enhancing Chesapeake Bay Program models using our improved understanding of water quality trends;
    • Informing management strategies to improve water quality;
    • Conducting a 2017 Midpoint Assessment; and
    • Adhering to the TMDL Accountability Framework.

    Monitoring progress toward the outcome will occur through model simulations of pollution-reducing practices and monitoring networks that track river flow; nitrogen, phosphorus and sediment in the watershed; air deposition; conditions in tidal waters relative to established water quality standards; conditions of tidal habitats; and the health of living resources. Monitoring and assessing progress toward the outcome will also occur through the 2017 Midpoint Assessment, which will review our progress, enhance our modeling tools and address emerging issues like climate change.

  • Work Plan
    Chesapeake Bay Program partners have committed to taking specific actions over the course of 2016 and 2017 to achieve the high-level approaches identified in the management strategy above.
  • Participating Partners

    The Water Quality Goal Implementation Team leads the effort to achieve this outcome. It works in partnership with the Scientific, Technical Assessment and Reporting Team.

    Participating partners include:

    • State of Delaware
    • State of Maryland
    • State of New York
    • Commonwealth of Pennsylvania
    • Commonwealth of Virginia
    • State of West Virginia
    • District of Columbia
    • Chesapeake Bay Commission
    • Natural Resources Conservation Service (U.S. Department of Agriculture)
    • U.S. Army Corps of Engineers
    • U.S. Department of Defense
    • U.S. Department of Homeland Security
    • U.S. Environmental Protection Agency
    • U.S. Geological Survey