Combating Nutrient Over-enrichment: Findings and Recommendations
This committee was charged to recommend ways to help coastal and watershed managers achieve meaningful reductions in the impacts of nutrient over-enrichment in the near-term. The committee was charged further to identify areas where scientific uncertainty and imperfect knowledge limit the nation’s ability to achieve long-term reductions in nutrient over-enrichment and its effects. The dichotomy in its charge required the committee to explore both current scientific understanding and resource management practice. This chapter, which summarizes the committee’s major conclusions, also reflects this dichotomy, with many of the key findings and recommendations organized to emphasize their relationship to common coastal or watershed management practice. If the nation is to address coastal nutrient over-enrichment successfully, efforts by local, state, and federal agencies must be coordinated nationwide. Thus, by keying the major components of a national nutrient management strategy to a common decision process followed by the managers working on-the-ground at local, state, and regional levels, the committee hopes to emphasize that, with a few important exceptions such as where problems span multiple jurisdictions, involve multiple sectors of the economy, threaten federally held resources, or fall under federal regulations like the Clean Air Act, nationwide improvement can best be achieved through coordinated local and regional actions.
DEVELOPING A NATIONWIDE STRATEGY TO ADDRESS NUTRIENT OVER-ENRICHMENT
Recent efforts to determine the extent of nutrient over-enrichment, such as the National Oceanic and Atmospheric Administration’s (NOAA) National Estuarine Eutrophication Assessment (Bricker et al. 1999), have been hampered by a lack of systematic monitoring and reporting and inadequate coverage of the nation’s coasts. Nonetheless, the available data clearly demonstrate that problems associated with nutrient over-enrichment occur nationwide and that impacts will worsen if current trends continue. As discussed earlier, NOAA’s examination of 139 coastal water bodies found that nearly one-third (44) are experiencing severe or worsening impacts caused by nutrient over-enrichment (Figure 1-1). The nutrient sources are diverse, often rooted in major changes in technology and human behavior over the last 50 years—ranging from significant changes in how agriculture is conducted to expanded use of fossil fuels. Solutions to the problems caused by nutrient over-enrichment are multi-faceted and vary from region to region.
Although there are large national programs that aim to “protect and restore coastal waters and habitat,” there is no nationwide strategy designed specifically to address excess nutrient inputs to coastal waters. At present, there is little accessible information or easily implemented and reliable methods for a decisionmaker or program manager in a coastal area to determine the sources of excess nutrients or the potential impacts of those nutrients to a specific coastal waterbody.1 Although many federal agencies are making significant independent efforts to help local jurisdictions deal with the effects of nutrient over-enrichment in coastal settings, the degree of coordination among these agencies and efforts remains inadequate.
The severity of nutrient-related problems and the importance of the coastal areas at risk demand the development and implementation of a National Nutrient Management Strategy. The National Nutrient Management Strategy should coordinate local, state, regional, and national efforts to combat nutrient over-enrichment in coastal areas, with the goal of seeing significant and measurable improvement in the environmental quality of impaired coastal ecosystems.
The effects of nutrient over-enrichment are site-specific, and the sources of nutrients vary greatly among regions and among particular sites. Consequently, development of a national strategy must allow for variation among sites and regions in the implementation of source-reduction goals and in the management and policy approaches used. However, some federal oversight is essential for issues such as the movement of nutrients across state boundaries. Many important coastal systems, including the “Dead Zone” in the Gulf of Mexico, Chesapeake Bay, and Long Island Sound, receive nutrient inputs from many states, and often from far away. Further, national policies are necessary to deal with nutrient sources from agriculture and from the combustion of fossil fuels, to ensure that pollution sources are not simply shifted from one region to another.
The National Nutrient Management Strategy must also facilitate the development of a national, coordinated effort to provide local decisionmakers and managers with the information they will need to determine appropriate source reduction goals and methods at the local level. Providing local decisionmakers and managers with this information base will allow site-specific and, where necessary, regional or even federal implementation of policies designed to yield significant and measurable improvement in the environmental quality of impaired coastal systems.
If the national strategy is to achieve a “measurable improvement” in the quality of impaired coastal systems, some systemic measure of change nationwide must be instituted. Even though the recent National Estuarine Eutrophication Assessment (Bricker et al. 1999) was hindered by inconsistent and inadequate data sets in many areas, and there was some subjectivity in the assessment process, it still represents the best measure of the extent to which nutrient over-enrichment has impaired coastal environmental quality. Thus the committee suggests that a similar assessment, repeated at roughly ten-year intervals, would be a useful mechanism to determine whether “measurable improvement” has, in fact, occurred. Beyond this, the national strategy should encourage more uniform approaches to monitoring of coastal systems across the country so that future assessments can be made with greater efficiency and accuracy.
Another goal of the national strategy should be “significant improvement” in coastal water quality, but what constitutes “significant improvement”? Local or state managers often face the dilemma of having to frame specific and achievable performance metrics or goals. As discussed in Chapter 8, establishing such goals requires input and commitment from a large number of stakeholder groups. Employing the kind of stakeholder process needed to set goals for a nation as large and complex as the United States is well beyond the scope of this study, which was designed to propose solutions to the intellectual and logistical barriers associated with nutrient over-enrichment. However, based on a review of current
Specifically, the committee believes that implementation of the recommendations contained in this report would provide local decisionmakers and managers with an information base that could be used to determine what can and should be done to halt the degradation of many of the coastal waters identified in the NOAA National Estuarine Eutrophication Assessment as demonstrating symptoms of severe or worsening eutrophication. The committee believes implementation of the recommendations would dramatically enhance efforts of coastal and watershed managers and other individuals or groups attempting to mitigate the effects of nutrient over-enrichment in these and other estuaries. Improvements in all impaired coastal bodies could be achieved over the next 20 years, while preserving the environmental quality of now-healthy areas.
What are reasonable goals for improvement? In the committee’s opinion, at a minimum federal, state, and local authorities should work with academia and industry to2:
reduce the number of coastal water bodies demonstrating severe impacts of nutrient over-enrichment by at least 10 percent by 2010;
further reduce the number of coastal water bodies demonstrating severe impacts of nutrient over-enrichment by at least 25 percent by 2020; and
ensure that no coastal areas now ranked as “healthy” (showing no or low/infrequent nutrient-related symptoms) develop symptoms related to nutrient over-enrichment over the next 20 years.
It was beyond the charge and resources of the committee to identify specific coastal areas for priority attention. All 44 of the areas identified by NOAA’s National Estuarine Eutrophication Assessment as exhibiting severe symptoms certainly should be considered as areas where greater effort is needed. Additional study could help further target priorities, especially if it included careful consideration of economic issues and opportunities for stakeholder input. Such work could take significant time and effort, and decisionmakers should not be tempted to defer action while waiting for “perfect” knowledge. The committee believes that
These goals are all in relation to the benchmarks determined by NOAA’s National Estuarine Eutrophication Assessment (Bricker et al. 1999, see Box 1-2). That report found 44 of 139 sites suffering high eutrophic conditions; 38 of the 139 sites studied showed low or no nutrient-related symptoms.
nationwide implementation of the recommendations in this report, across the full range of systems from small to large and problems from the simple to the complex, will start the nation on a course to achieve the goals stated above. Additional focus on areas subsequently identified for priority attention will then add to cumulative improvement. Thus, the goals listed above are intended to reflect nationwide achievement. Targeting some subset of the impaired coastal areas in an effort to simply meet these numeric goals (for instance, focusing on impaired water bodies associated with small watersheds or simpler ecosystems) would be contrary to the national interest and the spirit of this report.
Working to reduce the effects of nutrient over-enrichment nationwide over the next two decades will be a challenge, but the committee believes these general goals are realistic. The setting of such numeric goals is somewhat subjective, but the committee believes that such targets are important to encourage action. The goals were set after thorough discussion and are, in the committee’s view, both achievable given current methods and challenging enough to facilitate real progress. Many of the principles espoused in this report have already been implemented on a smaller scale in Europe (e.g., Rhine and Elbe watersheds) and the United States (e.g., Tampa Bay and Chesapeake Bay) and have resulted in significant reduction in nutrient loads received from nonpoint sources (Behrendt et al. 1999; Belval and Sprague 1999; Johansson and Greening 2000). However, achievement of these goals should not be seen as an end in itself. Rather, they are a first step toward reversing the effects of nutrient over-enrichment in the nation’s coastal waters and preventing impairment of “healthy” coastal areas.
How would these goals be accomplished? The key to addressing coastal nutrient problems is understanding that nutrient inputs to coastal waters are affected directly and significantly by activities in the watersheds and airsheds that feed the nation’s streams and rivers, and building this recognition into planning as well as implementation of management solutions. Thus, an effective National Nutrient Management Strategy must recognize the fundamental role that local watershed and coastal managers play. These individuals will be the front line of both policymaking and project implementation.
The committee believes that by focusing on source reduction, actions can be targeted to most effectively reduce and reverse the problems caused by nutrient over-enrichment in coastal areas. Watershed-specific sources like urban stormwater runoff and inappropriate nutrient management at the farm level often can be addressed most effectively by local activities under local leadership, with activities typically site-specific. However, while significant improvements can be achieved through local action, local managers alone cannot be expected to bring adequate resources and
knowledge to bear on such a complex problem, nor are they always able to work at the scale of larger watersheds. Sometimes, broader participation is necessary to bring about significant improvement.
Thus, what is required is a National Nutrient Management Strategy that emphasizes the need for local, state, and federal agencies to work together, and to create partnerships with academia and the private sector. First, federal leadership is essential to support and coordinate the research and development needed to provide new approaches and technologies that can be used by local and state agencies charged with reducing and reversing the impacts of nutrient over-enrichment. Perhaps even more importantly, federal leadership will be needed to deal with nutrient sources in large watersheds that span multiple states or jurisdictions. For example, the burning of fossil fuel by both mobile and stationary sources far from the coast can account for a significant component of the overall contribution of nitrogen from nonpoint sources in some watersheds. These watersheds, in turn, deliver that nitrogen to the sea, often hundreds of miles and many states away from the original source of emissions. Similarly, livestock feed is now shipped great distances to large, concentrated animal feeding operations. The cattle, hogs, or chickens in turn produce huge amounts of nitrogen- and phosphorus-rich wastes, which are ultimately released into a watershed that, again, may be several hundred miles and many states away from the original source of the nutrients.
Implementation of a National Nutrient Management Strategy to improve the understanding and management of nutrient over-enrichment and eutrophication requires action at two levels, local and federal. To facilitate these actions, the committee proposed two interrelated sets of recommendations. First are recommendations for a process to use at the local level now. Second are recommendations that address the development and implementation of federal activities to provide the long-term information, data, and analyses needed to address nutrient over-enrichment in coastal waters and support effective nutrient management strategies at the national, regional, and local levels.
A RECOMMENDED APPROACH FOR LOCAL MANAGERS
Figure 2-1 shows a decision-making framework that outlines the elements necessary in a process to help local, state, and regional managers make decisions about what steps and methods are appropriate to manage nutrients effectively in their area, recognizing their particular problems. This process is based on a number of recommended strategies, plus the experiences of local managers (EPA 1989; NRC 1990, 1999a; Schueler 1996; CENR 1998; Bricker et al. 1999).
Based on extensive discussions with managers and personnel from relevant federal support programs, review of published guidance documents, and detailed phone interviews with coastal managers from over 25 estuaries nationwide, the following text expands on the decision-making process to discuss what tools, analytical techniques, and data and information resources are available to help implement each step. The steps (keyed to Figure 2-1) are presented as a series of questions or decisions that the responsible manager would ask or make. The text also identifies what resources are available to support local managers. Thus, coastal or watershed managers dealing with nutrient management and its associated problems for the first time should find this a useful primer (references to chapters in this document where the reader can find more detailed information on the issue are included). The text also attempts to identify areas where greater resources are needed (in the vast majority of instances, federal or state leadership will be required). These areas are summarized, and specific federal actions are proposed to address them, in the last section.
Determine Status of Coastal Water Body: Is it Meeting Standards, Criteria, and/or Desired Uses?
The initial step of the decision-making framework is to determine whether the specific coastal water body in question is currently meeting standards, criteria, and/or desired uses. Characterization of the extent and severity of eutrophic symptoms (Chapter 4) may also include determining whether eutrophic conditions are natural or anthropogenic, and whether symptoms are seasonal or are exhibited throughout the year (Chapter 6). Existing standards and criteria vary from water body to water body; and many coastal areas currently do not have regulatory or non-regulatory guidelines for eutrophication or nutrient loading (Chapter 8).
Existing tools and information to assist with characterization of eutrophic symptoms include NOAA’s National Estuarine Eutrophication Assessment and an initial susceptibility index as developed by NOAA (see also Chapters 4 and 6).
Needed resources and research to support the characterization step include:
development of standards or guidelines for nutrient criteria or loads, including total maximum daily loads (TMDLs) that a waterbody can assimilate without exceeding criteria or affecting desired uses (Chapter 8);
greater information on the contribution of specific sources to nutrient loading (Chapter 7).
If the water body is not meeting standards or goals and the causes appear to be anthropogenic, the strategy moves to the “restoration” series of steps, labeled R1 through R7. If the water body is meeting standards or goals, then the decision-maker moves to the maintenance or “preservation” series of steps, labeled P1 through P4.
R1. Set Goals for Waterbody Restoration
If restoration is deemed appropriate, the first step is the setting of measurable goals for restoration. Goals can be regulatory (e.g., dissolved oxygen concentrations) or those adopted by stakeholders, such as seagrass acreage or water clarity (Chapter 8). If goals are stakeholder-determined, commitment by the stakeholders to participate in the process is essential for successful implementation.
Existing tools and information include guidance as summarized in a previous NRC report (NRC 1999a), guidance prepared for the National Estuary Programs (EPA 1989) and other guidance efforts (Schueler 1996; ASCE and WEF 1998).
Needed resources and research include:
historical information on the state of the water body in question (so that remediation goals can be more easily tied to previous conditions);
a compilation of experience from existing programs (to capitalize on the success of other efforts); and
ambient environmental data (to establish quantitative goals).
R2. Estimate Existing Loading and Develop Nutrient and Water Budgets
The next step is to develop nutrient and water budgets, including estimating nutrient loads from all sources to the coastal water body. This can be accomplished in several ways. Whenever adequate data from the contributing watershed are available, the recommended method is to use real measurements of discharge (flow) and nutrient concentrations to estimate the load contributed by surface water and groundwater (Chapter 7). However, in many instances adequate data are not currently available to calculate these estimates or to establish the actual sources (e.g., runoff from croplands, animal feeding operations, atmospheric sources), and a modeling approach must be used to estimate the surface water and groundwater load. These approaches range from simple spreadsheets to complex mechanistic techniques (Chapters 5 and 7).
Existing tools and information include flow and nutrient concentration data collected by the U.S. Geological Survey (USGS) and other state, local and federal entities, atmospheric deposition collected by the National Atmospheric Deposition Program and NOAA (very limited data from coastal areas), and various modeling approaches as reviewed in Chapter 7.
Needed resources and research include:
ambient environmental data (to more clearly identify sources and loads and to support or validate more robust modeling efforts as needed);
measurements of atmospheric deposition (wet and dry) to coastal surface waters (to better identify the relative role atmospheric sources play in contributing nutrients; Chapter 5);
evaluation of processes and retention of atmospheric deposition on various land-use covers (Chapter 5);
expanded USGS flow and nutrient concentration data collection in coastal watersheds (Chapter 7);
assessment of modeling approaches to address eutrophication (Chapter 7); and
evaluation of transferability of findings between existing studies, including scaling (Chapter 6).
R3. Determine Relationship between Loadings and Impact to Waterbody
The next step is to determine the responses of a water body to variations in nutrient loading. Responses may include changes in ambient
nutrient concentrations, algal biomass and turbidity levels, and other measurable changes (Chapter 4). Models currently used to calculate responses to variable nutrient loads range from simple regression approaches to linked watershed:water body hydrodynamic models, as reviewed in Chapter 7. Estimating the relationships between nutrient loads and responses in the water body (i.e., developing dose/response curves) and the relative susceptibility to changes in nutrient inputs for various classes of coastal waters will provide managers with critical tools to help answer “what if” questions concerning nutrient reductions or increases (Chapter 6). This will be a difficult task, requiring research.
Needed resources and research include:
the development of techniques to better predict the response of a given class of water body to a specific load (to allow for greater predictability and reduce reliance on trial and error approaches; Chapter 6);
further development and implementation of the classification scheme (to help assess susceptibility to nutrient over-enrichment; Chapter 6); and
assessment of the use and effectiveness of various models (Chapter 7).
R4. Determine Nutrient Load Reductions Needed to Meet Goals
The next step is to calculate the difference between existing loads (estimated in Step R2) and loads that would result in meeting water body goals (estimated in Step R3). An important consideration is that many coastal waters will not show immediate response to reductions or changes in external nutrient loadings, and managers should expect a lag time of months to years after nutrient input changes have been initiated (Chapter 9).
R5. Identify and Implement Most Effective Load Reduction Strategy and Projects
Stakeholder participation is critical in identifying the most effective strategies and projects (Chapter 8). Each watershed and coastal water body will have unique sets of potential strategies (regulatory and nonregulatory) and projects to help meet goals. Strategy development should
include consideration of the effectiveness of management practices (Chapter 9), economic assessments and incentives (Chapter 8), and an evaluation of the most cost-effective ways to meet goals (Chapter 8). Implementation will require strong and long-term commitment by the participants.
Existing tools and information include those sources listed under R1.
Needed resources and research, in addition to many of the recommendations listed in the previous steps, include:
compilation of economic studies that examine the relative costs of various approaches in a variety of settings, organized so that coastal decisionmakers can more readily identify relevant results and approaches;
identification, compilation, and making accessible a list of potential management options for each type of source, including costs and effectiveness of existing best management practices for urban, agricultural, and residential areas (to help achieve source reductions; Chapter 9) and recognizing the roles of existing regulations;
continued development of improved best management practices (Chapter 9);
evaluation of effective management structures for implementation (Chapter 8); and
continued identification of potential barriers (local, state, and federal levels) and development of ways to address these barriers.
R6. Monitor Results
Monitoring results of the implementation of a defined management approach can include several elements: ambient monitoring of the water body, monitoring of loadings, and monitoring of specific projects to determine effectiveness (Chapters 7 and 9). Measuring progress (or lack of progress) towards reaching goals provides a crucial “feedback loop” for participants and managers (Chapter 8).
Existing tools and information include ambient monitoring programs where available.
Needed resources and research include:
definition and implementation of a national ambient monitoring program, including source monitoring (Chapter 7).
R7. Progress Being Made toward Reaching Goals
Managers must ultimately be aware of whether the actions taken result in progress toward stated goals. Progress can be assessed by a variety of means, from casual observations by citizens and stakeholders, to simple visual examination of monitoring trends, to use of more sophisticated quantifiable methods of assessing monitoring data. Reporting results to stakeholders and the public on a timely basis is an important element of this step.
Existing tools and information include an example of a three-phase reporting system (as defined by the Chesapeake Bay Program) to report to scientists, managers, and the general public (NRC 1990).
Needed resources and research include development of quantifiable methods for assessing progress towards goals.
If progress is not found to be satisfactory, the manager should return to Step R3 (if new data may provide a revised relationship) or Step R5.
Maintenance or Preservation Steps
If, as is often the case, the initial evaluation step finds that the water body is currently meeting standards, criteria and/or stakeholder goals, the manager should work his or her way through a series of steps designed to ensure maintenance or preservation of the quality of the water body. These steps are:
P1. Evaluate Potential for Future Nutrient Over-Enrichment
Because the water body is currently meeting standards and goals, steps taken in this sequence should be simple and cost-effective, and designed to evaluate future potential for eutrophication. More detailed susceptibility evaluations can be used if the simple methods indicate possible problems in the future (Chapter 6). Simple evaluations (i.e., “red flags”) that indicate that the water body may be susceptible include:
large watershed size,
the watershed is experiencing rapid land use change,
long residence time in receiving water body,
a seagrass-dominated system,
often contains high levels of dissolved organic material (DOM), and/or
The initial susceptibility index developed by NOAA (Bricker et al. 1999) and used to assess current and future status of the nation’s estuaries in NOAA’s National Estuarine Eutrophication Assessment, in conjuction with other approaches discussed in Chapter 6, may be a useful starting point for determining the risk faced by a given water body and should be considered during this preliminary evaluation.
Existing tools and information include NOAA’s initial susceptibility index used in NOAA’s National Estuarine Eutrophication Assessment (Bricker et al. 1999).
Needed resources and research focus on further development of a systematic estuarine classification scheme and dose/response curves (Chapter 6). If the water body is considered potentially susceptible to nutrient over-enrichment in the future, continue to P2.
P2. Project Future Nutrient Loadings and Impacts to the Water Body
Tools similar to those described in Steps R2 and R3 to estimate existing loads can be used for this step, but in this case the effort should be more modest (e.g., measurements taken at regular, but less frequent intervals).
P3. Identify Most Effective Load Maintenance Strategy
This step will include the same basic considerations outlined in Step R5, with the objective of maintaining loadings below those that would result in detrimental effects. Determination of total maximum or “acceptable” loads (TMDLs or other determinations) for nutrients will be an important tool in this step.
P4. Implement Maintenance Strategy and Monitor Water Body
The monitoring recommendations outlined in Step R6 are also relevant for this step, although in this series they should be implemented at a modest or targeted level.
RECOMMENDED FEDERAL ACTIONS
To combat coastal nutrient over-enrichment in an effective, coordinated way, federal agencies, in concert with the White House and with the support of Congress, should develop and implement a National Nutrient Management Strategy. This national strategy should contain elements to address source identification, impacts, management approaches, and other local needs identified above. Furthermore, because many of the problems faced locally reflect regional processes beyond the purview of local jurisdictions, the strategy should include mechanisms to coordinate efforts at local, regional, and national levels. To minimize potential competition between agencies for limited funds, and to reduce unnecessary and costly duplication of effort, the mechanisms chosen to implement the National Nutrient Management Strategy will be critical and should build on existing efforts, like the Clean Water Action Plan (Box 2-1). These mechanisms could include convening multi-entity steering/oversight panels (possibly modeled after the Executive Office’s Committee on Environment and Natural Resources [CENR]; Box 2-2), which include representatives from relevant federal programs but also have strong state, regional, and local program participation, including citizen and industry groups. Regional or state oversight committees may be necessary to obtain adequate local and regional input. Federal support, both financial and technical, will be critical for the successful implementation of the national strategy. The proposed National Nutrient Management Strategy should strive to increase coordination and efficiency of ongoing efforts, promote technical exchange, strengthen monitoring, modeling, and research efforts, and support, to the degree possible, local management efforts.
Identify and Address Program Gaps and Overlaps
One of the first federal actions taken under the National Nutrient Management Strategy should be to develop and implement a process to assess overlaps and gaps in existing and proposed federal programs for all aspects of nutrient over-enrichment, with particular attention to the needs of local managers. This assessment should identify specific roles and responsibilities carried out by various federal agencies while recognizing the important roles that state and local governments, industry, and nongovernment groups play. Assessment results should be used to redirect resources from redundant efforts to areas where additional work is needed. An evaluation of the combined experiences of existing nutrient management programs and local programs, particularly their successful (and less successful) methods for determining sources of nutrients and
The Clean Water Action Plan is a multi-agency effort initiated in 1998 in commemoration of the 25th anniversary of the Clean Water Act (USDA and EPA 1998a). The Plan contains 111 key actions, many of which are relevant to nutrient over-enrichment in coastal waters, including:
potential impacts, could provide much needed information to both local managers and national policy makers. Specific actions to increase coordination at all levels would include:
Increase Attention Given to Atmospheric Deposition of Nutrients—Due to the geographic extent of airsheds (often many times larger than the watersheds that managers use as boundaries), federal programs, such as EPA’s Great Waters program, are encouraged to increase their efforts to quantify atmospheric deposition of nutrients to the nation’s coastal waters. Local programs should be encouraged to participate in a national monitoring program (such as the National Atmospheric Deposition Program) through offers of technical and funding assistance for development of monitoring sites, sample collection and analyses, and data analyses and interpretation. (The existing NADP database could be considered as the core for data management of atmospheric deposition.)
Consider Need for Nutrient Management During Reauthorization of the Clean Water, Clean Air, and Coastal Zone Management Acts—Obviously, the movement and concentration of nutrients among the biosphere, atmosphere, and freshwater and marine
The Committee on Environment and Natural Resources (CENR) was established by President Clinton to foster a multi-agency, interdisciplinary approach to environment and natural resources research and development and to coordinate federal efforts totaling approximately $5 billion in 1999. CENR was created in recognition that the traditional single-agency, single-discipline way of solving environmental and natural resource problems was no longer adequate. CENR addresses science policy and research and development efforts that cut across agency boundaries and provides a formal mechanism for interagency coordination on domestic and international issues. Twelve federal agencies participate on CENR committees (NSTC 1998).
The CENR, a committee of the National Science and Technology Council (NSTC), provides advice regarding the effectiveness and productivity of federal research and development efforts in the area of the environment and natural resources. The NSTC is a standing cabinet-level body chaired by the President and composed of the Vice-President, the Assistant to the President for Science and Technology, the cabinet secretaries and agency heads with responsibilities for significant science and technology programs, and other White House officials. The organizational structure of CENR includes full-committee and subcommittee vice-chairs (science and policy co-chairs) who bring high-level policy perspectives.
CENR consists of seven subcommittees representing areas of important policy that transcend the interest of any single agency: global change; biodiversity and ecosystem dynamics; resource use and management; water resources and coastal and marine environments; air quality; toxic substances and hazardous and solid waste; and natural disaster reduction. Coastal nutrient over-enrichment, including hypoxia and coordinated monitoring, is one responsibility within these subcommittees. CENR is recognized for its success in reducing coordination and interagency barriers, and could be used as a model for the proposed national strategy to combat nutrient problems. If used as a model, the structure would need to be adapted to include significant local and state participation.
systems is rarely affected by the jurisdictional boundaries of cities, counties, states, or nations. Thus, the sources and effects of nutrient over-enrichment will rarely be confined to a single political jurisdiction. Constructing effective regional or national policies or regulations to deal with the problems associated with nutrient over-enrichment will involve many of the issues addressed by these three acts. Thus, the implications of nutrient over-enrich-
ment should be an important consideration when Congress addresses the re-authorization of these important components of national environmental policy.
Complete and Implement the Clean Water Action Plan—To a very large degree, the actions called for throughout this report are represented or discussed in the Clean Water Action Plan currently under consideration. After revising the plan to address issues raised by this report and elsewhere, as appropriate, the plan should be implemented as quickly as is practical.
Accessible Data, Information, and Expertise
Local programs and agencies are using a variety of assessment and management tools to study and reduce the effects of nutrient over-enrichment in coastal settings, ranging from linked hydrodynamic water quality models to a purely technology-based approach. Although the complexity ranges among programs, managers believe that their processes are providing or are expected to provide adequate information to initiate management strategies; all, however, identified needs for additional assessment tools. In general, local managers cannot wait for answers from the scientific community. They must use what they perceive to be the best available or most appropriate information to compile nutrient budgets by source type, to estimate potential impacts from management practices, and to develop and implement management strategies. However, some managers may not be aware of better sources of information, indicating a communication problem between the scientific and management communities. Managers recognize that the data sources and tools that they currently use need improvement.
Better mechanisms for communicating information could lead to rapid improvement in management plans. As one of its initial actions, those implementing the National Nutrient Management Strategy should create mechanisms to provide consistent and competent technical assistance from federal agencies to local decisionmakers and agency staff. This might include development of a national clearinghouse and access to on-request assistance and review. The following should be considered high priority and parallel actions:
Develop a national information clearinghouse—Understanding how the effects of nutrient over-enrichment are manifest or vary from estuary to estuary is an important step for coastal managers who must deal with nutrient over-enrichment. A web-based clearinghouse for information on the effects of nutrient over-enrichment should be established with links to federal, state, and local
assistance programs, on-request technical assistance, contacts, and the metadatabase recommended below. In addition, relevant economic studies should be integrated and organized so that decisionmakers can readily identify available information on the economic viability of different management approaches from similar coastal settings or for similar nutrient sources. Many federal and state programs already have extensive websites or databases that should be directly linked to the clearinghouse.
Develop a metadatabase of distributed information and data—Determining the validity or applicability of information requires an understanding of the data and techniques used to collect it. The metadata3 supporting the information clearinghouse should be easily accessible for all users. All partners in the coordination effort should be encouraged to link their existing sites to the metadata site, although partners should continue to be responsible for updating and controlling the quality of their own databases. As various databases are developed to meet emerging local, state, regional, or national needs for information relevant to nutrient over-enrichment, they should be linked to both the metadata website and included in the clearinghouse discussed above.
Expand Federal Leadership
Federal leadership is critical to address issues that span multiple jurisdictions, involve several sectors of the economy, threaten federally held resources, or fall under existing federal regulations such as the Clean Air Act. This leadership should be manifest in several ways including specific actions to help establish credible goals and mechanisms, including:
Set Clear Guidelines for Nutrient Loads—The development of critical nutrient loads (above which nutrient over-enrichment and eutrophication symptoms may be expected) are essential to successful nutrient management strategies (Chapter 8). EPA’s efforts to develop nutrient criteria and TMDLs should incorporate interaction among physical, chemical, and biological factors, seasonal
and timing imports, and the nature of hydrologic forcing functions (Chapter 8). These efforts should, however, focus on identifying sources and setting maximum loads, rather than on limiting the ambient concentration of a given nutrient in a receiving water body (Chapter 5).
Reduce Impact of Agriculture Practices—Technological and organizational advances in agriculture have made North America one of the leading producers of foodstuffs worldwide. However, information is still often lacking on the impacts of agriculture on various ecosystems. National and regional strategies are needed to help address the introduction of excess nutrients from various agricultural practices. Farmers’ decisions are often influenced by regional or even global economics. At these scales, farmers have little or no control over these economic pressures and the resulting changes in nutrient flows and distribution. Therefore, new ways of using incentives to help farmers implement innovative source reduction and control will be needed (Chapter 9).
Evaluate Existing Efforts to Determine Elements of Success—Conduct an evaluation of the combined experiences of the local, state, and federal programs, highlighting successful (and less successful) methods for determining sources of nutrients, potential impacts, and management strategies, to provide needed information to both local managers and national policy makers. Identify, compile, and make accessible a list of potential management options for each type of source, included costs and effectiveness of existing BMPs for urban, agricultural and residential areas (Chapter 9); continue research and development of new best management practices (Chapter 9).
Expand Monitoring Capabilities
The United States lacks a coherent and consistent strategy to monitor the effects of nutrient over-enrichment in coastal settings on a regular and consistent basis. The NOAA assessment effort (Bricker et al. 1999) is an admirable one, but it is limited by the inconsistency of data collection among estuaries. One consequence is that the full economic and ecological impact of nutrient over-enrichment is not currently demonstrable.
Implementation of a nationally consistent monitoring program will be a critical component of the proposed National Nutrient Management Strategy because monitoring brings better characterization of the spatial extent and temporal trends of nutrient over-enrichment in estuaries and coastal waters. Such a program must be commensurate with the scale of the issue. The best approach is probably to use a partnership of efforts by
local, state, and federal agencies, as well as academic and research institutions where appropriate. Consistent procedures, criteria, quality control, and data management and reporting are essential. Monitoring should include biological, physical, and chemical properties on time and space scales relevant to capture the necessary variability and linkages between variables. Often, this will mean that biological and chemical measurements will need to be made at finer scales than is presently the norm, while additional collection of long-term data will be needed to detect subtle change. Monitoring programs should be regularly evaluated by independent panels to determine their effectiveness. Further, monitoring programs should be adaptive, incorporating new technology and scientific understanding while preserving the long data time series necessary to detect trends. Selection of monitoring sites should be made with consideration of classification schemes that illustrate estuarine susceptibility to nutrient over-enrichment. It is likely that incentives will need to be developed to encourage widespread state and local implementation of consistent quality control and metadata standards (Chapter 7).
Representative coastal systems (e.g., index sites) should be selected to serve as sites for long-term, intensive research programs to better understand the effects of nutrient enrichment on estuarine structure and function, and to track how changes in management affect coastal systems. Index sites must be representative of the range of estuarine “types” included in the classification and should be selected in parallel with development of an overall classification scheme for susceptibility to nutrient over-enrichment, as described in Chapter 6. Index sites should be chosen to show varying degrees of human impacts. Research at index sites can help explain temporal patterns of change revealed through monitoring and assessment programs, and is essential to develop better predictive models for management.
Estimates of nutrient inputs to estuaries are essential for management, and data on long-term trends on nutrient inputs are invaluable for determining sources of nutrients. Throughout the United States, the USGS is the best and primary source of data on nutrient inputs to estuaries from upstream rivers. The data it collects are invaluable, and continuation of this monitoring is essential. However, the USGS monitoring networks were not designed to assess inputs to coastal regions, and should be expanded to include this role.
Other recommendations that support the development of a nationally consistent monitoring program include:
Implement a national monitoring framework including the adoption of a three-tiered national monitoring program similar to that
Establish representative or index sites (as defined by the susceptibility classification) where long-term, intensive research programs are conducted to better understand the mechanisms controlling eutrophication processes and the effects of nutrient enrichment on estuarine structure and function for the various classifications (Chapter 7).
Include monitoring of the effectiveness of nutrient management projects and strategies, including BMPs (Chapter 9).
USGS monitoring should be expanded with the specific objective of assessing nutrient inputs to estuaries and monitoring how these change over time. Further, monitoring data collected by the state and local agencies should be used more fully. Often, these data are collected for other purposes (such as assuring drinking water quality), yet they could provide useful information on nutrient inputs to estuaries if adequate quality control were maintained (Chapter 7).
Develop and implement regional or national monitoring and management strategies for atmospheric deposition. Expand deposition monitoring to better represent urban and coastal areas. Improve dry deposition monitoring and model efforts (Chapter 5).
Conduct Periodic Comprehensive Assessments of Coastal Environmental Quality
One key deficiency in the nation’s approach to coastal water quality deficiencies is the lack of periodic, comprehensive analysis like the recent NOAA National Estuarine Eutrophication Assessment. In the future, such efforts will be particularly important because they would provide information about how systems have changed, which is critical for understanding whether policy and management choices have been effective in causing improvements. Thus, the nation needs to conduct a periodic (every 10 years) reassessment of the status of eutrophication in the nation’s coastal waters (similar in scope to NOAA’s 1999 National Estuarine Eutrophication Assessment).
Develop a Susceptibility Classification Scheme
The National Nutrient Management Strategy should encourage further development and use of a classification scheme to determine a given estuary’s susceptibility to nutrient over-enrichment (Chapter 6). An important goal of coastal zone managers is to accommodate human actions
while minimizing the impact on coastal ecosystems. Successful management requires considerable information at a variety of levels, including an understanding of systems in their natural, pristine condition as well as how natural systems respond to human activities (Karr and Chu 1997). In coastal waters, the situation is particularly acute because the different types of estuaries, embayments, and shelf systems differ in their response to nutrient enrichment. Thus, a given nutrient input results in different response trajectories in various types of systems.
A widely accepted estuarine classification scheme is a prerequisite for a systematic approach to extending lessons learned and management options from one estuary or affected coastal water body to others. Such a classification scheme should allow categorization of relatively poorly known systems on the basis of a minimum suite of measurements. Quantitative classifications that provide insights into the relative importance of the different factors controlling estuarine dynamics have the most potential for predictive analysis. A high priority should be the development of a national framework of “index sites,” within which there would be an integration and coordination of environmental monitoring and research with the goal of developing a predictive understanding of the response of coastal systems to both nutrient enrichment and nutrient reduction.
Improve Models to Support Coastal Managers
Largely due to the high cost associated with monitoring, it is impractical for managers to collect and assimilate enough observational data to fully understand the effects of changes in land use patterns. Furthermore, even if adequate observational data could be obtained, understanding the processes involved sufficiently to predict future conditions is difficult. Consequently reliance on complex and simple models to forecast environmental conditions has become widespread. This approach couples the benefits of reducing the need for prohibitively large monitoring systems with rapid exchange of the information generated by increasingly sophisticated computer technology. More effort needs to be made to convey modeling methods and results widely (Chapters 6 and 7). This will also require additional efforts to develop a database of typical input values (organized by watershed and receiving waterbody type) for use in existing models. Such efforts will be instrumental for developing quantifiable methods for assessing progress towards goals, an essential element of effective resource management (Chapter 8).
Expand and Target Research
The potential impacts of atmospheric deposition of nutrients on coastal waters and its contribution to the effects of nutrient over-enrichment is just beginning to be estimated and fully recognized by local, state, and federal agencies and managers. As noted earlier, due to the large geographic extent of airsheds, local and state programs cannot adequately address this issue alone. In addition to the expanded monitoring effort called for earlier to address the atmospheric deposition of nutrients, additional efforts should also be directed by national programs toward quantifying sources, fate, transport, and impacts (including economic) of atmospheric deposition of nutrients on watersheds.
In addition, federal programs that fund basic research (such as EPA, the National Science Foundation [NSF], and NOAA) should provide competitive grants for academic support for research into the role atmospheric deposition plays in nutrient over-enrichment. The implications for reducing the effects of nutrient over-enrichment through implementation of the Clean Air Act should be a major component of the national dialog concerning coastal environmental quality.
Additional research is needed to address the relative role that nitrogen and phosphorus nutrients play in specific freshwater and marine systems, and how those roles vary seasonally (Chapter 3). Greater research effort is needed in order to better understand the role of specific nutrients in the occurrence of various harmful algal blooms, and how toxic algae of all types can endanger fish and birds, as well as humans and other organisms at higher levels of the food web (Chapter 4). Finally, research is needed that builds understanding of the effects of nutrient inputs on economically valuable resources (e.g., oysters, fish stocks, etc.) so we are better prepared to do the analyses necessary to compare costs and benefits and set acceptable restoration goals.
Support Local Management Initiatives
The strategies used by local programs and agencies for minimizing the effects of nutrient over-enrichment range from entirely educational and non-regulatory to primarily regulatory. In many instances, the most appropriate approach is a combination of voluntary and regulatory approaches that grant flexibility and are designed to achieve goals at minimum costs.
However, few local programs to date report that their strategies for reducing the effects of nutrient over-enrichment actually seems to be providing observable improvements. Others report that it is either too early to tell, or that results are mixed. Reasons for lack of observable effects
vary, from inadequate modeling or data, to lag times in seeing results, to ineffectual management actions. In general, many of these programs could benefit from independent, objective analysis of the effectiveness of their planning, assessment, and management processes.
The local, state, and federal elements of the proposed National Nutrient Management Strategy could provide information and assistance with the development and implementation of effective management at all levels, and a means for objective independent review. As noted many times in this report, effective management is site-specific and unique for every estuary and coastal water body, with no universal “right answers.” An adaptive management approach, using accessible and emerging tools, knowledge of successful techniques, coupled with and supported by a strong monitoring program, appears to provide the highest probability of long-term success.