511 (BOY-1117-209225) Historical Patterns and Ecological Interactions Associated with Eutrophication in Chesapeake Bay.
Start time: 1:50 PM
Boynton, W¹, Kemp, W², ¹ Univ MD Chesapeake Biological Lab, Solomons, MD, USA² Univ MD Horn Point Laboratory, Cambridge, MD, USA
A synthesis of diverse Chesapeake Bay data sets provided insights regarding eutrophication patterns and ecological consequences. Various analyses indicated initial signs of organic enrichment 200 years ago, increased algal growth and declines in water clarity 100 years ago, and recurring deep-water hypoxia/anoxia and loss of submersed vascular plants since 1950. Degradation of benthic habitats appears to have contributed to declines in abundance and production of mesohaline macrofauna and polyhaline blue crab populations. In contrast, copepod communities, which are heavily grazed, appear relatively unaffected by nutrient-induced changes in food abundance and phytoplankton species composition. Intense fisheries harvest and disease have caused a dramatic decline in oyster reefs and associated filtration of estuarine water and also exacerbated eutrophication effects on phytoplankton and water clarity. There is little direct evidence that overall fisheries production has been affected by nutrient enrichment, but demersal fish catch and food web efficiency have both declined suggesting fundamental changes in ecosystem structure. Ecosystem responses to nutrient load changes tend to be non-linear involving important roles for benthic plants and oxygen effects on sediment biogeochemistry. Recent nutrient load reductions have elicited rapid responses for some ecosystem functions but lags in others.

512 (BAT-1117-746428) Assessing and Managing the Impacts from Nutrients and Sediments: Chesapeake Bay Lessons Learned.
Start time: 2:10 PM
Batiuk, R¹, ¹ U.S. Environmental Protection Agency, Annapolis, Maryland, USA
The Chesapeake Bay Program is the unique regional partnership that's been directing and conducting the restoration of the Chesapeake Bay since the signing of the historic Chesapeake Bay Agreement of 1983. The Chesapeake Bay Program partners include the states of Maryland, Pennsylvania and Virginia; the District of Columbia; the Chesapeake Bay Commission, a tri-state legislative body; the U.S. Environmental Protection Agency, representing the federal government; and participating scientific, citizen and local government advisory groups. With the adoption of the Chesapeake 2000 Agreement came an unprecedented opportunity to use decades of estuarine research and monitoring data to define restored Chesapeake Bay water quality and establish far reaching nutrient and sediment reduction goals. The resultant Bay specific water quality criteria, dissolved oxygen, water clarity and chlorophyll, along with tidal habitat, defined designated uses have been adopted by Maryland, Virginia, Delaware and the District of Columbia as water quality standards. Using a unique integration of monitoring data and model simulated outputs, caps on nutrient and sediment loads required to achieve the Bay criteria were allocated to 44 sub-basins across the six-state, 64,000 square mile Chesapeake watershed. The critical roles played by estuarine science, resource managers and senior policy officials in deriving these precedent setting criteria and nutrient and sediment loading cap allocations will be illustrated.

513 (BEA-1122-325172) Water Quality Protection and Restoration in the Chesapeake Bay: A Maryland Perspective.
Start time: 2:30 PM
Beaman , J¹, Eskin, R¹, ¹ Maryland Department of the Environment
The overarching water quality goal of the Chesapeake 2000 ("C2K") Agreement is to achieve and maintain the water quality necessary to support the aquatic living resources of the Bay and its tributaries and to protect human health. To that end, Maryland and the other Bay jurisdictions and watershed states embarked on a process to, "correct the nutrient- and sediment-related problems in the Chesapeake Bay and its tidal tributaries sufficiently to remove the Bay and the tidal portions of its tributaries from the list of impaired waters under the Clean Water Act by 2010". The major tasks associated with this goal included defining the water quality conditions necessary to protect aquatic living resources, assigning load reductions for nitrogen and phosphorus to each major tributary, and adopting new or revised water quality standards consistent with the defined water quality conditions. The new standards will now be used as the basis for removing the Bay and its tidal rivers from the list of impaired waters. The presentation will address Maryland's perspective on dealing with the scientific and management complexities of developing and promulgating Chesapeake Bay water quality standards and attainment procedures into state water quality standards and how they have become the drivers for meeting the goals and commitments within the Chesapeake 2000 agreement.

514 (EVA-1122-324810) Chesapeake Bay Restoration Symposium.
Start time: 2:50 PM
Evans, D¹, ¹ McGuirewoods, LLP
During its 2005 session, the Virginia General Assembly adopted innovative legislation that is expected to significantly accelerate and intensify reductions in nutrient loads to the Chesapeake Bay from point and non-point sources in Virginia. The legislation codifies Virginia's Chesapeake Bay nutrient load cap allocations, authorizes nutrient credit trading to facilitate cost-effective compliance with the allocations using a watershed general permit as the implementation mechanism, and establishes a framework for acquiring nutrient offsets to accommodate continued growth and economic development in the watershed without exceeding the nutrient load caps established for each of Virginia's five Chesapeake Bay tributaries. Although this legislation offers significant flexibility and opportunities for cost savings, it also presents unprecedented challenges for Virginia state and local governments, industry, and developers. This presentation will discuss the legislation, its innovative cost-savings features, and the issues and challenges that must be addressed and overcome if the nutrient cap is to be achieved and maintained in the face of continued grown in Virginia's Chesapeake Bay watershed.

(59356) Break.
Start time: 3:10 PM

515 (HUN-1117-738153) The Science of Chesapeake Bay Nutrient Standards: A Municipal Perspective.
Start time: 3:50 PM
Hunley, W¹, Bell, C², ¹ Hampton Roads Sanitation District, Virginia Beach, VA, USA² Malcolm Pirnie, Inc., Newport News, VA, USA
Ambient water quality criteria for dissolved oxygen, water clarity, and chlorophyll a for the Chesapeake Bay and tidal tributaries were published by the USEPA in 2003. Since their publication the States have promulgated (or are in the process of promulgating) those criteria into their water quality standards. The development of a scientifically defensible chlorophyll a standard for the James River, Virginia has been controversial. This presentation will outline the municipal concerns regarding the efficacy of this standard to affect meaningful environmental benefits. The role of excessive inorganic suspended sediment based turbidity and the historical loss of filter-feeding stocks will also be discussed as factors complicating a restoration of the James River system. Alternative management solutions and needs for further research will be indicated.

516 (BRE-1117-666484) The importance of scale and location to the ecological and economic benefits of restoration.
Start time: 4:10 PM
Breitburg, D¹, Nice, A², Adamack, A³, Jordan, T¹, Weller, D¹, Lipton, D⁴, Fulford, R¹, Lung, W², Rose, K³, ¹ Smithsonian Environmental Research Center, Edgewater, MD, US² University of Virginia, Charlottesville, VA, US³ Louisiana State University, Baton Rouge, LA, US⁴ University of Maryland, College Park, MD, US
The scale and location of restoration efforts are influenced by funding constraints, the size and location of jurisdictional boundaries, and a desire to increase stakeholder involvement. We used a series of linked watershed, water quality, fisheries and economic models of the Patuxent River and adjacent Chesapeake Bay to investigate the differences in benefits gained from local vs. regional restoration. The models show that the location and percentage of agriculture and developed land within the Patuxent watershed strongly affects nutrient discharge and chlorophyll concentrations in the river, but has virtually no effect on bottom layer hypoxia. Instead, the extent and severity of hypoxia, which influences both mortality of early life stages of fishes and the ability of oysters (if restored) to remove chlorophyll from the water column, is almost entirely controlled by nutrient concentrations and carbon entering the river from the mainstem Chesapeake Bay. Thus, local stakeholders may reap greater benefit from regional than local restoration, and water quality goals will only be met by efforts at both scales. Regional efforts are also required to reap the economic benefits of restoration. Because fishers can adjust to long term local (Patuxent River) water quality degradation by fishing in other areas, significant economic gains are more likely to be realized when water quality improvements occur over the larger set of choices of fishing locations, that is, regional scale improvements. Applying strict cost-benefit analysis to local restoration improvements may fail to capture the benefits from the cumulative effects of restoration projects that lead to regional improvements in water quality. Regulations that result in a decoupling of the timing or magnitude of local and regional restoration efforts, and lead to benefits that differ from public expectations, may affect the willingness to pay and stakeholder political support for restoration.

517 (SPA-1117-829461) Use of dredged materials for landscape-scale island and tidal wetland habitat restoration in Chesapeake Bay.
Start time: 4:30 PM
Spaur, C¹, Johnson, S ¹, ¹ U.S. Army Corps of Engineers, Baltimore, MD, USA
Society′s vision for the desired condition of the Bay over the next several decades includes continued presence of large expanses of tidal wetlands and isolated islands. There has been historic loss of both of these habitat types as a consequence of the combined impacts of natural and anthropogenic causes, and they remain on a downward trend. Dredged materials from navigation channels will provide the principal material means to restore substrates of tidal wetland and isolated island habitats. Several ongoing and proposed U.S. Army Corps of Engineers′ projects being undertaken in conjunction with the Maryland Port Administration are of particular importance in this regard. Upon completion, the ongoing Poplar Island Environmental Restoration Project would restore/create approximately 1,140 acres of remote island habitat; proposed future expansion would add approximately 550 acres of remote island habitat. Proposed future placement of dredged material at James Island would create/restore about 2,000 acres of remote island habitat. The Poplar and James Islands projects would produce roughly half upland and half tidal wetland habitats. Proposed wetland restoration in and around the Blackwater National Wildlife Refuge area of Dorchester County using dredged material has the potential to restore thousands of acres of tidal wetlands.

518 (MEN-1122-325526) Applying a multi-stressor and relative risk framework for understanding factors influencing conditions within Chesapeake Bay.
Start time: 4:50 PM
Menzie, C¹, Amos, B¹, ¹ Menzie-Cura & Associates, Inc.
Biological, physical, and chemical stressors vary throughout the Chesapeake Bay. The role they play in shaping conditions depends on local factors as well as factors that operate at larger scales. The relative importance and cumulative effects of physical alterations, nutrient inputs, harvesting, toxics, and introduced species must be viewed within this multi-scale framework. This paper illustrates how conceptual models and a multi-stressor relative risk framework can be used to organize information at varying scales. The approach is designed to lay information out in a manner that is understandable by people with varying degrees of scientific understanding. As such it affords a useful communication tool. For illustration, the approach is focused on three types of regions and regional problems: Baltimore (toxics, nutrient inputs, dissolved oxygen, sedimentation, loss of sea grass beds), island systems within the Bay (physical erosion, sediment enrichment, development), and the Bay at large (dissolved oxygen, nutrients, loss of SAV, toxics, introduced species.

519 (BOE-1122-324287) Chesapeake Bay - People, Policies, Pollutants, and Perseverance: A Vision for the Future.
Start time: 5:10 PM
Boesch, D¹, ¹ University of Maryland Center of Environmental Sciences
For decades, scientists, environmental managers, politicians, and the Chesapeake Bay communities have worked toward addressing the physical, chemical, and biological pressures influencing conditions with the Chesapeake Bay. With great effort, accords have been reached about how to approach the most pressing problems. The SETAC symposium on the Bay has identified trends in resources as well as identified some of the major pressures. The Bay is inextricably linked not only to things that occur within the Bay but also to an expansive watershed that includes a number of states. Charting a path toward approiate management for the Bay has not only been a technical challenge but also an economic and political one. Perhaps as much as any place in the United States, addressing these challenges has required arriving at a shared understanding among a diverse assemblage of stakeholders that don't always share the same view and who differ in the degree to which they impact the Bay, participate in the benefits of improved water quality conditions, or are otherwise impacted by decisions. With this diverse fabric of people, policies, and pollutants, the path forward often seems as turbid as some of the Bays tributaries. This paper, provides an overview of where we currently stand as we make efforts to move forward. It identifies some of the challenges and constraints and highlights the opportunities to make progress.