Chesapeake Bay - Case Study

The Chesapeake Bay water quality deteriorated from a variety of pollutants during a time of population growth and more intensive agricultural practices during the 1960s, 1970s and continuing to the early 1990s. As a result of the Clean Water Act of 1972, various pollution control measures were instituted resulting in measurable improvements in the water quality.

• In 1984, the Commission was at the center of a coordinated effort to ban the use of phosphate detergents in all three Bay Program states.
• The Commission has been a strong proponent in the passage of key land-use laws that protect the Bay's shorelines, such as Maryland's Critical Area Act and Virginia's Chesapeake Bay Preservation Act.
• After signing the 1992 Amendments to the Chesapeake Bay Agreement, which committed the signatories to reducing nutrients in the Bay's rivers as well as the Bay itself, the Commission helped establish the process for developing these tributary strategies and passed a resolution to ensure their success.
• In 1994, the Commission sponsored successful legislation in Pennsylvania requiring certain livestock operations to develop and implement nutrient management plans to protect Bay waters.
• Realizing the importance of riparian, or stream side, forests to both water quality and habitat in the watershed's streams and river, in 1994 the Commission adopted a resolution to maintain and restore riparian forests. This kicked off a major initiative to develop a watershed-wide Bay Program policy on the restoration of riparian forest buffers.

For this case study, you will identify various water pollutants and methods of controlling them. As part of the debate, the general question will be: What further measures need to be taken to obtain further declines in the amount of nutrients which enter the bay?

Participants in the debate will represent the following interests:

• Municipal Sewage Treatment Plants
• Farmers and large landowners

INTRODUCTION AND OVERVIEW OF THE PROBLEM:

• Chesapeake Bay Program - Overview.
  What is the purpose of the program?
  
  
• Chesapeake Bay and Watershed - graphic
  
  
• State of the Chesapeake Bay, 1995.
  Lots of information about the Bay and the ecosystem. Do not have to look at all of it, but get an overview to put the problems in prospective.
  
  
• Population Growth and Wastewater Discharges.
  What are the main pollutants called nutrients (chemical names?) resulting from population growth, conversion of individual septic systems to municipal waster water treatment?
  
  
• Overall Nutrient Sources and Reduction Goals.
  What is the result of excess nutrients in the water?
  
  
• Key Chesapeake Bay Commission Issues
  What steps have been taken to control nutrient pollution?
  
  

In general, if necessary, click on the speakers notes for a description of the graphs which follow: Threats to the Bay - Nutrients, Toxic Chemicals, Habitat Loss, and Over Fishing

• Portrait of an Ecosystem.
  Look very carefully on the left side of the graphic to describe the relationship of nutrients to algal growth to dying algae.Why does this produce low levels of oxygen? Hint: Think of decomposition by bacteria. BOD. For further help see the next graphic.
  
  
• Effects of Pollutants on the Bay
  
  

• Overall watershed Nutrient sources.
  Pie charts for nitrogen and phosphorus. What source is the main contributor for the pollution caused by nutrients?
  
  
• Acres under nutrient management.
  Be sure to check out the Òspeakers notesÓ on this one explain what measures are taken for agricultural nutrient management.
  
  
• Phosphorus loads delivered to the Bay.
  Again be sure to check out the Òspeakers notesÓ on this one to find the definitions of point sources and nonpoint sources and then compare the amount of reductions for both sources.
  
  
• Nitrogen loads to the Bay.
  What is shown on these slides about nitrogen reduction?
  
  
• Dissolved Oxygen levels in the Bay
  What are the trends for dissolved oxygen in the bay?
  
  
• Trends in Blue Crab Harvest
  What are the trends in the Blue Crab harvest?
  
  
• Trends in Oyster harvest
  What are the trends in the Oyster harvest?
  
  
• Toxics in oysters
  What are the trends in the toxic levels of mercury and chloradane in oysters?
  
  
• Municipal Wastewater discharge of phosphorus
  What do these graphs show about the discharge levels of phosphorus since the Clean Water Act?
  
  
• Municipal Wastewater discharge of nitrogen
  What do these graphs show about the discharge levels of nitrogen since the Clean Water Act?
  
  
• Environmental Indicators
  This is the main menu for the environmental indicators that were selected above. Use only if you need or desire to look at more of them.
  
  

About two thirds of the way down in the article this paragraph appears: ÒThe October 1996 draft of the strategy proposed that the final 4 percent nutrient reduction gap be closed through the implementation of nutrient removal technology at all of the larger municipal wastewater treatment facilities across the Shenandoah Potomac basin. This proposal was not supported by local officials in the Shenandoah Valley and Lower Potomac region, who believe that it unfairly placed the burden of closing the nutrient gap on areas of the basin that had worked cooperatively with the state to meet their regional nutrient reduction target. In addition, it would substantially diminish the capability of these areas to reserve future nutrient reduction measures that would help maintain their regional nutrient reduction caps as the population grows.Ó

• Municipal Waste Water Treatment Nitrogen Discharges
  What statement is made about the feasibility of controlling nitrogen through BNR technology?
  
  
• Tributary Strategy Goals for the Upper Potomac
  List some of the examples of things in all areas that are being implemented.
  
  
• Chesapeake Bay Area Nutrient Management Programs: An Overview
  Check the following sections: Introduction, Plan Definition and Criteria, Progress Update, Urban Nutrient Management, Vision for the Future
  
  
• RECOMMENDATIONS FOR ACTION for the Nutrient Management Group
  What are some of the actions recommended?
  
  

DEBATE QUESTION:

What further measures need to be taken to obtain further declines in the amount of nutrients which enter the bay?

During the debate two groups of students should represent the following interest groups: Municipal Sewage Treatment Plants and Farmers / large landowners. What balance of actions should be taken in light of the evidence of nutrient loads from the point and nonpoint sources and the the progress made to date?

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