According to data submitted by Delaware, Maryland, Virginia and the District of Columbia to the U.S. Environmental Protection Agency in 2014, 80 percent of the Chesapeake Bay’s tidal segments are partially or fully impaired by toxic contaminants. Chesapeake Bay Program partners have set a goal to observe no such impairments. The latest listings of impaired waters under Section 303(d) of the Clean Water Act mark a continued increase in the observation of toxic contaminant impairments since 2010. An analysis to determine whether this observed increase is the result of a rise in the number of tidal segments analyzed or an actual decline in environmental conditions has not been conducted.

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Toxic Impairments in the Tidal Chesapeake Bay (2010-2014)

Percentage of Tidal Segments in Delaware, Maryland, Virginia and the District of Columbia with Partial or Full Impairments Due to Chemical Contaminants

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Toxic Impairments in the Tidal Chesapeake Bay (2014)

While chemical contamination is often characterized as a localized problem occurring in “hot spots” or “regions of concern,” metals, polychlorinated biphenyls (PCBs) and priority organics exceed water quality criteria in at least part of all of the tidal tributaries that deliver water to the main stem of the Bay. Because toxic contaminants are present in the water column, persist in bottom sediment and build up in the tissue of fish and other organisms through a process known as bioaccumulation—impacting the health of fish and other ecological resources—there may be little positive short-term change in this indicator of environmental health even if the input of toxic contaminants to our waterways declines.

A technical report shows PCBs and mercury are particularly problematic in the region, and are considered widespread in severity and extent. Polycyclic aromatic hydrocarbons (PAHs) and some herbicides are also considered widespread in extent, while dioxins, petroleum hydrocarbons, some chlorinated insecticides and some metals occur locally. Information is insufficient to determine the extent of biogenic hormones, household and personal care products, pharmaceuticals or flame retardants.

Toxic contaminants can harm human health and affect the survival, growth and reproduction of fish and wildlife. Increasing our understanding of toxic contaminants is critical to the drafting of policy and prevention approaches that will reduce their effects on living resources.

Management Strategy

To achieve this outcome, Chesapeake Bay Program partners have committed to:

  • Supporting programs that monitor the occurrence of PCBs;
  • Supporting the development, evaluation and implementation of toxic contaminant Total Maximum Daily Loads;
  • Compiling data for enhanced regulatory programs;
  • Developing a guidance document for the control and reduction of PCBs in regulated stormwater and wastewater;
  • Coordinating educational workshops to increase public knowledge of the impacts PCBs can have on human health, the risks of consuming contaminated fish and the technologies available for sediment remediation;
  • Coordinating voluntary programs to track the sources of PCBs and phase out PCB-containing equipment;
  • Exploring opportunities to reduce the inadvertent manufacture of PCBs; and
  • Improving the information available for reduction strategies.

As part of the Chesapeake Bay Program’s partnership-wide implementation of adaptive management, progress toward this outcome was reviewed and discussed by the Management Board in May of 2018.

Work Plan

Chesapeake Bay Program partners have committed to taking a series of specific actions that will support the management approaches listed above.

Completed actions from this outcome's work plan include:

  • In 2016, the Chesapeake Stormwater Network completed a study to determine the relative amount of toxic contaminant reduction that might occur across the range of best management practices implemented as part of the nutrient- and sediment-focused Chesapeake Bay Total Maximum Daily Load (Bay TMDL). Part One of the study examines how practices meant to control stormwater can remove urban toxic contaminants from the environment, while Part Two examines how the agricultural and wastewater sectors influence antibiotics, biogenic hormones and pesticides.
  • In 2016, the Toxic Contaminants Workgroup completed a story map depicting the extent of jurisdiction-listed waters that are impacted by PCBs. Additional maps that depict the need for, development of and presence of active PCB Total Maximum Daily Loads were built to help partners target activities related to PCB reductions.
  • During 2016, U.S. Environmental Protection Agency (EPA) enforcement personnel conducted four PCB inspections at facilities in the watershed.

Participating Partners

The Water Quality Goal Implementation Team leads the effort to achieve this outcome.

Participating partners include:

  • Delaware Department of Natural Resources and Environmental Control (State of Delaware)
  • Maryland Department of the Environment (State of Maryland)
  • Maryland Department of Natural Resources (State of Maryland)
  • New York Department of Environmental Conservation (State of New York)
  • Pennsylvania Department of Environmental Protection (Commonwealth of Pennsylvania)
  • Virginia Department of Environmental Quality (Commonwealth of Virginia)
  • West Virginia Department of Environmental Protection (State of West Virginia)
  • Department of Energy and Environment (District of Columbia)
  • Chesapeake Bay Commission
  • National Oceanic and Atmospheric Administration
  • U.S. Department of Homeland Security
  • U.S. Environmental Protection Agency
  • U.S. Fish and Wildlife Service
  • U.S. Geological Survey