Public Release: 

Scientists urge outcome-based, watershedwide approach to restore the Chesapeake

Maryland Sea Grant

WASHINGTON, DC -- More than twenty years after the historic Chesapeake Bay Agreement set out a roadmap for a coordinated clean-up effort at state and federal levels, the region is struggling to follow it, scientists say.

Panelists speaking at a February 20 session of the American Association for the Advancement of Science (AAAS) in Washington, DC emphasized the importance of an adaptive approach to restoration in the Chesapeake--which scientists call adaptive management, in which ideas and approaches can be tested, checked for success, and adjusted along the way.

"We are headed in the right direction, we know where we want to go, but need to be more efficient and accountable in order to get there," says Donald Boesch, president of the University of Maryland Center for Environmental Science.

And this modify-as-you-go approach to restoration should be "watershedwide," panelists say, including upland streams and rivers, not only the Bay and its living resources--such as crabs, oysters, and underwater grasses.

"What happens every day in backyards and on street corners that are miles and miles from the Bay proper have huge impacts on Bay health," according to ecologist Margaret Palmer from the University of Maryland, College Park.

"Restoration of the Bay will not occur unless we stem the loss of headwater streams and freshwater wetlands and restore non-tidal waters," Palmer says.

Palmer is working on the large-scale National River Restoration Science Synthesis Project, to inventory and evaluate ongoing stream and river restoration projects in the Chesapeake watershed. She analyzed existing written records and found that fewer than 5% of these projects have been evaluated for success after completion, a significantly lower percentage than other regions in her analysis.

The panel also addressed the need for a watershedwide approach to limit nitrogen input to Chesapeake Bay--which causes the excessive growth of algae and leads to the depletion of oxygen in the bottom layers as it dies, falls to the bottom, and decomposes.

Agricultural fertilizer runoff plays a dominant role in contaminating the Bay with excess nitrogen and has long occupied center stage in restoration efforts. But emissions to the atmosphere from cars and stationary sources, deposited later on the landscape, may be more significant than previously thought, according to biogeochemist Robert Howarth from Cornell University in Ithaca, NY.

Climate change will further compound the nitrogen problem in the Bay, Howarth reports. In the absence of management actions, nitrogen flux down the Susqhehanna River, the Bay's largest tributary, could increase as much as 17% by 2030 and up to 65% by 2095 due to predicted warmer, wetter conditions, he finds.

So what approach can scientists, managers, and citizens take to reverse the Bay's downward spiral?

"We must think across the boundaries that traditionally lead to disjointed, uncoordinated efforts in freshwater and coastal systems," says Jonathan Kramer, session organizer and director of the Maryland Sea Grant College, part of a network of 30 university-based programs that support innovative marine research and education.

"We have plotted a good course for restoration. What we need now is a method of course correction that encourages us to make adjustments along the way," Kramer says.


AAAS/Sea Grant Panel Transcending Boundaries: Challenges for Holistic Restoration in the Chesapeake Watershed

Jonathan Kramer (Moderator), Maryland Sea Grant Program, Email:, Telephone: 301-403-4220
Restoration efforts in the Chesapeake Bay should cross traditional boundaries and include upland and coastal areas of the watershed. Chesapeake Bay has a strong foundation for this approach and can become a model for design and implementation of innovative restoration.

Lance Gunderson: Ecological Resilience and Adaptive Management: Lessons for the Chesapeake Bay Watershed, Emory University, Email:, Telephone: 404-727-2429
Management of large-scale natural resource systems such as the Chesapeake Bay Watershed involves confronting ecological, institutional, social and political complexities. Critical to success is an approach that incorporates adaptive management, a modify-as-you-go tactic, and thinking about ecological resilience, or the ability of an ecosystem to withstand perturbation without a fundamental change.

Margaret Palmer: Backyards to the Bay: Why We Have Been Lulled into False Complacency, University of Maryland College Park, Email:, Telephone: 301-405-3795
Restoration of the Chesapeake Bay can only succeed through coordinated efforts in upland watersheds. Our analysis, through the National River Restoration Science Synthesis Project, has found that the number of restoration projects per river and stream mile in the Chesapeake watershed is the highest in the nationwide, but fewer than 5% of them have been evaluated for success after completion.

Scott Phillips: Freshwater, Sediment, and Nutrient Delivery to Chesapeake Bay U.S. Geological Survey, Email:, Telephone: 410-238-4252
New understanding of the factors that contribute to the "lag time" between implementation of restoration practices and the response of the Chesapeake Bay ecosystem will improve planning and targeting of management actions to provide the most rapid water quality improvement.

Donald Boesch: Watershed Management Requirements for Chesapeake Bay Restoration, University of Maryland Center for Environmental Science, E-mail:, Telephone: 410-228-9250 x601
Adaptive management approaches that match modeling and monitoring will be required to progress in Bay restoration. Incentives for reducing agricultural pollution will be key, as will implementation of Clean Air Act requirements for atmospheric nitrogen reduction where regional actions alone are likely to be insufficient.

Thomas Bott: Ecosystem Services in Upland Streams: Implications for Watershed Restoration, Stroud Water Research Center, E-mail:, Telephone: 610-268-2153, ext. 224
Measurements comparing ecosystem metabolism in streams with forested v. meadow-vegetated buffers find greater processing of organic matter in forested areas. Management strategies that include restoration of forest along streams in upland areas will reduce the rate of delivery of nutrients and pollutants downstream.

Robert Howarth: Sources of Nitrogen and the Influence of Climate on Nitrogen Delivery to Chesapeake Bay, Cornell University, Email:, Telephone: 607-255-6175
Nitrogen originating from fossil fuel combustion (vehicle emissions) that is deposited onto the landscape and swept downstream may be even greater than previously estimated and should be a high priority for restoration efforts in Chesapeake Bay. We also demonstrated that watersheds in wet climates deliver more nitrogen downstream than those in dry climates. The influence of climate variability and climate change should be evaluated in restoration efforts.

Thomas Fisher: Land Use and Estuarine Restoration Goals in the Patuxent and Choptank Rivers, University of Maryland Center for Environmental Science, Email:, Telephone: 410-221-8432
Primary sources of nitrogen input to the Patuxent and Choptank rivers, two large Maryland tributaries of Chesapeake Bay, differ according to watershed characteristics. Agricultural fertilizer, a nonpoint-source of nitrogen, dominates in the more rural Choptank watershed, while human waste from sewage treatment plants is the main source for the more urbanized Patuxent. Restoration efforts in these rivers should be tailored to fit individual watershed qualities.

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