Chesapeake Bay Monitoring
"Monitoring for Management Actions"

1. introduction

The State of Maryland is actively pursuing a management policy to protect and restore the economic and recreational value of Chesapeake Bay. To assist in this goal, the Maryland Office of Environmental Programs (OEP) has designed and implemented a Chesapeake Bay Water Quality Monitoring Program. The purpose of this program is to provide State managers and policy makers with accurate, timely and comprehensive information about the Bay's existing condition and how it is responding to management initiatives. This information is required to evaluate current management policies and to formulate new goals and policies in the future. Perhaps most importantly, the results of the monitoring effort will provide a yardstick with which to measure progress towards the ultimate goal of protecting and restoring Chesapeake Bay.

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The information by itself, however, will not clean up the Bay. Measurable progress can be expected only when this information is used in the development, implementation and evaluation of management actions. Furthermore, the struggle toward progress will be difficult in the face of mounting population pressures. A long-term commitment to develop and maintain technically sound management plans is the only real hope for success in restoring vitality to Chesapeake Bay.

Presented here are the results of the first two years of the monitoring program.  During this period (summer 1984 through summer 1986) a major campaign has been initiated to reveal the present condition of the Bay in quantitative terms, to assess how the Bay is changing in response to management decisions, and to determine the causes of the current decline. At this early stage in the program, an unprecedented understanding of the Bay's current condition has already been achieved. It is this developing understanding of current conditions that will be the focus of this report. Future reports will examine in more detail the Bay's response to management actions and some of the underlying causes of the Bay's problems.


In order to insure that the OEP effort is capable of supporting effective management actions, it is imperative that the program be logically formulated. Past experiences indicate that the probability of success in satisfying this program's objective will be enhanced because the following elements were considered during the initial program design:
  • A clear statement of the relevant management issues to be addressed,
  • The development of specific management questions that define the information needed for management actions,
  • The design of a technically sound and practical sampling program,
  • A timely analysis, interpretation and presentation of results, and
  • The development of management policies and actions.

The remainder of this chapter will present a discussion of each of these five elements using examples to demonstrate the actual processes that were followed. A further discussion of the last step, development of management actions and policies, will be presented in the final chapter.


The first task that managers and scientists face before they can initiate efforts to restore the health of the Chesapeake Bay and its major tributaries is to clearly define what the major management issues are. Success in restoring the Bay will logically depend on a clear conceptualization of the problems we are trying to correct. This conceptualization of the management issues will then lead to specific actions that are perceived as necessary to bring about a recovery. Of course, the definition of management issues and management actions will significantly impact the design of the monitoring program and the ultimate application and utility of the monitoring results.

In 1983, the Environmental Protection Agency and the States of Maryland and Virginia completed a seven year, $27 million program to characterize the existing state of the Bay, to study the causes of the observed declines in the Bay, and to propose strategies needed to begin corrective measures. Relying on available historical data and supplemental information collected by the EPA/States program, the major management issues were identified as:

  • Declining levels of oxygen in Bay waters,
  • Increasing levels of phytoplankton (microscopic plants) due to nutrient enrichment,
  • The presence of toxic materials, and
  • Declines in living resources.

Once the broad management issues were defined, there was a need to develop more specific questions that would guide future management actions and serve as a focus for evaluating their success or failure. Answers to these management questions are the pieces of information necessary to develop technically sound actions and policies.


Management questions were formulated for each of the major management issues presented above. Consideration was given to the information already available from existing monitoring and research programs. Some of the management questions were relatively well studied by the State, and sufficient information was available to continue existing management plans. For several of the management questions, the available data was determined to be insufficient to develop revised or new management strategies.

To illustrate the concept, examples of management questions formulated for each of the management issues are given below:

Decreasing Oxygen Levels:

Where are the major areas of low dissolved oxygen waters in the Chesapeake Bay System?
Is the areal extent of low dissolved oxygen water expanding over time?
Which pollutant inputs are most responsible for the low oxygen conditions?

Increasing Phytoplankton Levels:

Where are phytoplankton blooms a major problem?
Has the severity of phytoplankton blooms in impacted areas, such as the Potomac and Patuxent Rivers, decreased since 1980 when management initiatives were being implemented?
What is the relationship between nutrient levels and phytoplankton biomass?


Where are the major concentrations of heavy metals in the sediments of the Bay?
Are toxicants levels in the sediments of historically impacted areas, such as Baltimore Harbor, decreasing?
Are toxicants that are accumulating in the sediments also entering the food chain?


Where is striped bass spawning succeeding or failing in the Bay system?
Are oyster stocks declining?
What environmental factors, for example food resources and acidity, are correlated with spawning success of fish in nursery regions?

Examination of the spectrum of major management questions revealed that they could be separated into 3 major categories:

  • Questions about the spatial and temporal characterization of each problem
  • Questions about observed trends in time
  • Questions about processes and causes relating to the major management issues

These three categories of management questions thus became the guiding objectives for designing the monitoring program. The specific physical, chemical and biological components of Bay water quality that were chosen for monitoring were those considered necessary to adequately address the major management issues.

The first two objectives of the monitoring program - characterization and trend - were considered to be goals that were fully-achievable by the monitoring program. At this time an initial characterization using the monitoring results is possible, although we will achieve greater confidence and reliability in this assessment with several years of data. The initial characterization is the subject of this report. The identification of trends will be an ongoing objective as management actions are continually being evaluated. The third objective - processes and causes - requires a synthesis of monitoring data with research and modeling programs to achieve definitive answers to most management questions in this category. There are also management questions that are not fully covered under the water quality program such as those related to living resources; these questions are being addressed by other State programs specific to this problem. Nonetheless, there are important questions relating to living resources that cannot be answered without the comprehensive perspective of the current water quality monitoring program.


The design of the present monitoring program is predicated upon the management issues and questions discussed above. The program will only be successful to the degree that it can ultimately respond with sound answers to the management questions being posed. Thus, in assembling the program details, the attainment of these answers was always the foremost consideration.

To reach its stated goals, it is essential that the program be technically sound. State-of-the-art scientific knowledge was incorporated into all phases of the monitoring design to assure technically defensible results. For each discipline contained in the monitoring program, OEP scientists solicited technical reviews from recognized experts.

To be implemented effectively and sustained for the time necessary to yield results, the monitoring program also needs to be logistically and economically practical. This means that the program is scaled properly, is efficient, measures the minimum number of the meaningful variables, and is flexible enough to change when necessary.

Finally, the complex physical, chemical and biological processes characteristic of estuarine systems must be considered in the design of an effective monitoring program. Without a solid understanding of how these processes influence the selection of variables to be measured, sampling frequencies, measurement methods, and data analyses techniques, the results will have limited application to management policy formulations. A description of these important processes and how they influence the problems facing Chesapeake Bay is contained in the next chapter.

A brief description of the overall program design is presented in Chapter 3. In each subsequent chapter that addresses elements of the monitoring program, more specific aspects of the program design are discussed prior to the presentation of results.


A critical step that determines the usefulness of the monitoring program is the analysis of date, interpretation of the findings and presentation of results. This final link is necessary to bring the wealth of information collected under the monitoring program into coherent and usable products. These products complete the sequence of events that allow the program to fulfill its objective of providing management with a valuable planning and assessment tool. Too often, ambitious and well-intentioned programs have floundered at this crucial final stage.

In order for the monitoring data to be used in the decision making process, it must first be meaningfully analyzed by one or more objective techniques. For some applications, a simple graphical analysis may suffice because the patterns are obvious or the analysis is exploratory in nature such as examining potential cause and effect relationships. Graphical analysis is also valuable for the preliminary phases of data analysis when, in many cases, insufficient data is available to warrant specific statistical tests. Graphical representations of the data are the principal products in this report because we are presently in the preliminary phases of data analysis.

In more rigorous levels of data analysis, objective statistical techniques are applied to evaluate hypotheses. Hypotheses, in the context of the monitoring program, are simply a formulation of the management questions into a statistically testable statement. For example, one of the management questions stated above concerning increased phytoplankton levels and the effectiveness of management initiatives since 1980 could be formulated into the following specific hypothesis: Phytoplankton levels in the tidal fresh area of the Potomac River during summer have not changed since 1980. An appropriate statistical test could then be applied to either accept or reject this hypothesis. If the hypothesis was rejected and levels actually were shown to decline since 1980, the management question concerning trends in phytoplankton for this region would be answered. The use of statistics must be very carefully applied, however, paying particular attention to the assumptions of each technique in relation to the data that is available from the monitoring program. In fact, the requirements of statistical testing was one of the critical factors considered in the program's design to insure that appropriate data would be collected.

Once the monitoring data has been analyzed, the results must be interpreted in the context of the management decisions that will depend upon this information. Often, there will be numerous specific results from several different monitoring elements that must be synthesized into a unified finding about a particular management issue. It is also important that the results from the monitoring data be accompanied by some statement of the confidence, or scientific uncertainty, that should be associated with a particular finding. Confidence in the findings could include limits on the estimates of particular measurements of the Bay's condition or limits on the geographical locations to which a result may apply.

Finally, the interpretation of results should conclude with recommendations for management policies. This is the culmination of the sequence of events upon which that entire program is based. It presents managers with a suggested course of action based upon the careful evaluation of monitoring results. Of course, there are other considerations, as will be discussed in the following paragraphs, that also influence the final decisions on management policies and actions.


The degree to which OEP's monitoring program results are incorporated into the formulation of management policy and actions directed towards Bay restoration will determine the true efficacy of the program.

In almost all management decisions aimed at restoring the Bay, several issues must be considered. First, there is the technical foundation for the decision. This is where the monitoring program is expected to be a powerful tool. Sometimes the monitoring data will be used in conjunction with computer models to provide an added dimension of forecasting the outcome of a variety of potential management strategies. Results from research studies may also provide technical input in the area of cause-and-effect relationships.

Other important considerations that will bear upon a final management policy are the priorities of citizens who could be affected by the decision, the economics of the decision and the available technology to support the implementation of a particular management policy.

In the end, however, it is the monitoring program that will provide the verdict on the success of individual or collective management decisions. These evaluations will either lead to a strengthening of our original management positions or to a reformulation of strategies to provide more effective measures aimed at restoring the Bay's health.

A more detailed description of the strategies that will be used in the development of policies and management actions will be the subject of the final chapter.

1.   Introduction
2.   Understanding The Bay's Problems
3.   Program Description
4.   Chemical and Physical Properties
5.   Plankton
6.   Benthic Organisms
7.   Ecosystem Processes
8.   Pollutant Inputs
9.   Management Strategies and the Role of Monitoring
10. Glossary

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