a science-based strategy for ecological restoration in south florida

Urban Ecosystems, 3, 201–222, 1999c© 2000 Kluwer Academic Publishers. Manufactured in The Netherlands.

A science-based strategy for ecological restorationin South Florida

MARK A. HARWELL ∗ and JOHN H. GENTILECenter for Marine and Environmental Analyses, Rosenstiel School of Marine and Atmospheric Science, Universityof Miami, Miami, FL 33149, USA

ANN BARTUSKAForest Management, U.S. Forest Service, 201 14th St. SW, Washington, DC 20250, USA

CHRISTINE C. HARWELL† and VICTORIA MYERS‡

Center for Marine and Environmental Analyses, Rosenstiel School of Marine and Atmospheric Science, Universityof Miami, Miami, FL 33149, USA

JAYANTHA OBEYSEKERA and JOHN C. OGDENSouth Florida Water Management District, P.O. Box 24680, West Palm Beach, FL 33416, USA

STEPHEN C. TOSINICenter for Marine and Environmental Analyses, Rosenstiel School of Marine and Atmospheric Science, Universityof Miami, Miami, FL 33149, USA

Abstract. The Everglades and associated coastal ecosystems of South Florida are unique and highly valuedecosystems. One of the world’s largest water management systems has been developed in South Florida over thepast 50 years to provide flood control, urban and agricultural water supply, and drainage of land for development.However, this system has inadvertently caused extensive degradation of the South Florida environment, resultingin the loss of more than half the historical Everglades system and elimination of whole classes of ecosystems.The U.S. Man and the Biosphere Program (US MAB) instituted a project to develop ecosystem managementprinciples and identify requirements for ecological sustainability of South Florida. A strategic process developedby the US MAB project illustrates how ecosystem management and ecological risk assessment principles applyto South Florida, including the development of societal goals and objectives of desired sustainable ecologicalcondition, translation of these goals/objectives into scientifically meaningful ecological endpoints, creation of aregional plan designed to meet the sustainability goals, and development of a framework for evaluating how wellthe plan will achieve ecological sustainability of South Florida. An extensive federal, state, and tribal interagencyprocess is underway to develop a restoration plan for restructuring the regional management system, essentiallyfollowing the elements in the US MAB project process. The Florida Governor’s Commission was established asan institution to reflect societal values and define regional sustainability goals. The U.S. Army Corps of Engineersis developing a science-based plan for Congressional approval to restructure the water management system toachieve the societal goals. Thus, South Florida may become the prototype example of successful regional-scaleecosystem management.

Keywords: ecosystem management, ecological risk assessment, sustainability, Everglades restoration, human–environment interactions

∗To whom correspondence should be addressed.†Present Address: Harwell Gentile & Associates, L.C., 58 Seascape Drive, Hammock, FL 32137, USA.‡Present Address: World Wildlife Fund, 1250 24th Street, NW, Washington, DC 20037-1175, USA.

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Background and historical development

The Everglades and associated coastal ecosystems of South Florida are among this nation’smost endangered ecosystems. Almost six million people now live on a narrow strip ofland along the coasts of South Florida, increasing by almost 1 million per decade (Gannon,1996; Soleckiet al., this volume). The historical Everglades and coastal ecosystems of SouthFlorida were characterized by the large spatial scale of the landscape arrayed as a complexmosaic of diverse ecological communities, connected by sheet flows of very low nutrientwater and supporting vertebrate species that required expansive territory (Beard, 1938;Browder and Ogden, this volume; Craighead, 1968; Davis, 1943, 1994; Daviset al., 1994;Davis and Ogden, 1994a; Douglas, 1947; Gunderson, 1994; Light and Dineen, 1994; Long,1974; Loveless, 1959; Myers and Ewel, 1990; Webb, 1990). Large interannual variabilityin precipitation controlled the dynamics and sustainability of the wading bird populationsand their food resources (Bancroftet al., 1994; Browder and Ogden, this volume; Dueveret al., 1994; Frederick and Spalding, 1994; Gunderson and Snyder, 1994; Ogden, 1994;Robertson, 1962). Conversion of natural lands for urban and agricultural uses, provisionsfor flood protection of the human populations, and extensive use of ecological resources forrecreational and commercial activities have resulted in major environmental alterations tothe region (Blake, 1980; Boeschet al., 1993; Bottcher and Izuno, 1994; Daviset al., 1994;Harwell, 1997, 1998; Light and Dineen, 1994; Snyder and Davidson, 1994; Soleckiet al.,this volume). More than half of the original areal extent of the historical system has nowbeen lost, including the elimination of whole classes of ecosystems (Chapman, 1991; Daviset al., 1994; Harwellet al., 1996; Harwell, 1997, 1998; Tebeau, 1990).

Hydrologic modifications to the region during the last half-century have been extensive.The U.S. Army Corps of Engineers’ (US ACOE) Central and South Florida Flood ControlProject (C&SF) is one of the largest water management systems in the world (Light andDineen, 1994; US ACOE, 1960, 1994, 1998) (figure 1). The C&SF was created to supportspecific needs of society (especially for flood control, urban and agricultural water sup-ply, and drainage of land for development) in response to a series of episodic events offlooding and drought (Soleckiet al., this volume). However, while addressing these societalneeds, the C&SF has inadvertently caused extensive degradation of the regional environ-ment (Bancroftet al., 1994; Davis and Ogden, 1994b; McIvoret al., 1994; Walterset al.,1992).

Several other anthropogenic stressors significantly affect the regional ecosystem, includ-ing (a) habitat modifications, particularly conversion of natural areas to agricultural andurban uses; (b) nutrient enrichment, especially increased phosphorus (P) in the historicallyoligotrophic surface waters, resulting in altered ecological communities; (c) overharvest-ing of resources, primarily fish and invertebrate populations of the coastal ecosystems; (d)extensive recreational use, particularly affecting the coral reef communities of the FloridaKeys National Marine Sanctuary (FKNMS); (e) toxic chemicals, primarily methylmercurycontamination of the Everglades and urban toxics in the Miami River and nearby areas ofBiscayne Bay; and (f) global change, in which the regional ecosystems are especially at riskfrom sea-level rise (Aultet al., 1998; Davis, 1994; Harwell, 1998). Of all these stressors,hydrologic modifications clearly constitute the dominant anthropogenic stressor in South

SCIENCE-BASED STRATEGY FOR ECOLOGICAL RESTORATION 203

Figure 1. The South Florida water management system. Historically the surface water flowed from the KissimmeeRiver watershed, through Lake Okeechobee, and as sheetflow across the landscape to Florida Bay and the southwestcoast. Currently, much of the surface water is discharged to tide through the St. Lucie Canal and the CaloosahatcheeRiver, and the remaining water is heavily channelized in and around the Water Conservation Areas, significantlychanging the quantity and timing of water releases into the Everglades.

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Florida (Harwellet al., 1996). As a consequence of the cumulative effects of human ac-tivities, the South Florida environment continues to decline and is not sustainable underthe present water management system and practices (Daviset al., 1994; Davis and Ogden,1994a, b; Harwellet al., 1996; Harwell, 1997, 1998).

The environmental problems in the region became apparent in the late 1980s, highlightedwhen the federal government initiated a lawsuit against the State of Florida for not imple-menting water quality regulations; the lawsuit focused on the nutrient-enrichment effectsfrom agriculture in the upper wetlands ecosystem. However, while minimum schedules andflows of water to Everglades National Park had been addressed by earlier negotiations, thelawsuit did not confront the system-wide hydrological modifications problem. This wasin part because enforceable regulations existed to control releases of nutrients, whereasonly operational guidelines controlled water quantity and timing. There was also a lackof understanding of the relative risks to the ecosystem, i.e., to what degree hydrologicalmodifications are more ecologically adverse than the effects of nutrient enrichment.

When Governor Lawton Chiles entered office in 1991, he admitted fault on the partof the State of Florida. A settlement agreement was quickly reached and later codifiedinto the Everglades Forever Act (State of Florida, 1995). This act required the estab-lishment of artificial wetlands in the southern part of the Everglades Agricultural Area(EAA) for phosphorus removal prior to release of surface water into the upper Evergladessystem.

In 1990, the U.S. Man and the Biosphere Program (US MAB) Human-Dominated Sys-tems Directorate initiated a long-term project on ecological sustainability of the region,developing and applying principles of ecosystem management, ecological risk assessment,and ecological sustainability to examine potential scenarios for sustainability (Harwellet al.,1996; Harwell, 1997, 1998). Through its analyses, the US MAB project concluded that un-der the Everglades Forever Act, the Everglades would in fact not be “forever,” because theact predominantly addressed the nutrient issue, leaving the more critical hydrologic modi-fication issues unresolved. The US MAB project also concluded that the lack of sufficientwater entering the natural Everglades is not simply a result of competition for water amongthe urban, agricultural, and ecological interests, which was the general perspective of thetime. Rather, the US MAB project concluded that whereas all three uses require about equalamounts of water on an average annual basis, over an order of magnitude more water (about7× 109 liters per day; US ACOE, 1998) is released to estuaries through the canals thatdrain the system for flood protection (figure 1). As a result, the fundamental issue is notwater availability into the region but the storage and release of low-nutrient water at theright times, in the right amounts, and at the right locations into the natural system. The USMAB project developed a series of scenarios to address the hydrological problem (Harwellet al., 1996).

In 1992 and 1996, the US Congress authorized the US ACOE to review the C&SFProject and determine if it should be modified to restore the South Florida ecosystems whileimproving water supplies and maintaining flood protection (US Congress, 1996; US ACOE,1998). The Corps established a project called the Restudy, which in concert with federal,state, and tribal partners is developing a comprehensive plan for the C&SF, which wassubmitted to Congress in July 1999. The Corps has released a draft plan and environmental


impact statement (US ACOE, 1998), available at website www.restudy.org, that describesthe historical and current problems, proposes a plan for restructuring the C&SF, and providesinitial cost estimates for the restoration (on the order of $7.8 billion). The proposed planis a result of a large number of model simulations of the hydrological consequences ofmany different possible system modifications, assessed against a set of desired goals for theecological and human system that were largely derived from the activities of the FloridaGovernor’s Commission for a Sustainable South Florida (Governor’s Commission, 1995,1996, 1998).

The Governor’s Commission was established by Governor Chiles in 1994 as a diversecommission of about 50 involved citizens representing many different stakeholder groups inthe state, including business leaders (e.g., agriculture, development), environmental leaders,local government representatives (e.g., mayors, county commissioners), tribal representa-tives, and other interested parties (Governor’s Commission, 1995). The commission hasbeen a prototype institution that explicitly addresses the interface between the analyti-cal and deliberative processes called for by the National Research Council (NRC, 1996).That is, the Governor’s Commission has worked closely with various scientific and tech-nical advisory groups to understand the South Florida ecological and human system, toarticulate a set of goals, objectives, and subobjectives reflecting diverse societal values,to explore possible futures for that system, and to provide guidance to the Restudy effort.The Governor’s Commission developed a preferred plan for restructuring the hydrologicsystem, as well as addressing many other regional problems, which both reflected theecosystem management concepts of the US MAB project and provided a template for theRestudy in the development of its draft proposed plan (Governor’s Commission, 1996,1998).

Another unique institution is the South Florida Ecosystem Restoration Task Force, es-tablished by the White House to coordinate the development of consistent policies, re-search activities, and priorities across the federal, state, and tribal governments. The SouthFlorida Restoration Task Force is composed of seven federal agencies, six state agencies, theGovernor’s Commission, and two Native American tribes. To facilitate the immense taskof coordinating and integrating the activities of these organizations, the task force createda Management and Coordination Working Group. Within this working group, there area series of subgroups that focus on topics related to science, management, infrastructure,public information and education, and social science. The mission of these subgroups is toprovide technical information and feedback to the working group and the task force. Thetask force recognized the need for a structured, strategic approach that integrates the diversescientific and management activities of the restoration process.

Strategic process

In response to this need, the US MAB team developed a strategic plan for bringing scienceto bear more effectively on the South Florida environmental decision-making process. Thecore of this approach is an integration of ecosystem management principles with a risk-basedassessment and decision framework.

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Ecosystem management principles

The US MAB project developed a set of ecosystem management principles (Harwellet al.,1996; US MAB, 1994) based on the frameworks of ecological risk assessment (Gentileet al.,1993; US EPA, 1992) and ecological sustainability (Harwellet al., 1996) (discussed below)and applied these principles to the South Florida case study (Harwellet al., 1996; Har-well, 1997, 1998). The nine US MAB Project ecosystem management principles (Table 1)are similar to those proposed in GAO (1994), IEMTF (1995a, b), and Christensenet al.(1996).

Remarkably, the US MAB project principles of ecosystem management accurately de-scribe the actual process that has unfolded through the institutions and processes of theGovernor’s Commission, the COE Restudy, and the South Florida Ecosystem RestorationTask Force. The process has not yet been completed, and there remain forces opposed to theregional management of South Florida and to the specifics of the Governor’s Commissionand Restudy plans (Harwell, 1998). Nevertheless, it appears at this juncture that there is areasonable probability that large-scale restructuring of the regional system may derive froma science-based strategy for ecosystem management.

Table 1. US MAB Project ecosystem management principlesa.

1. Develop a shared vision of desired ecosystem conditions—societal values must be the basis of environ-mental goals.

2. Use an ecological approach to recover and sustain the biological diversity, ecological function, anddefining characteristics of natural ecosystems—management to be based on ecological science,addressing human activities and decisions within landscapes.

3. Recognize that humans are part of ecosystems, and they shape and are shaped by the natural system—sustainable ecological and societal systems must be mutually interdependent.

4. Adopt a management approach that recognizes that ecosystems and institutions are heterogeneous intime and space—ecosystems and institutions are complex systems operating over multiple temporaland spatial scales.

5. Manage ecosystems with regard to sustained economic and community activity—management shouldbalance human and ecological requirements for sustainability.

6. Integrate the best science as a basis of the decision-making process, while continuing to improve thebasic scientific understanding of ecosystems—science informs the decision-making process, andresearch priorities should focus on reducing uncertainties.

7. Implement ecosystem management principles through coordinated government and nongovernmentplans and activities—ecosystem management principles constitute a framework in which manage-ment options are identified, analyzed, selected, and implemented.

8. Provide for ecosystem governance at appropriate ecological and institutional scales—decisions shouldbe made at neighborhood, local, and regional levels with recognition of the interconnectedness ofthese decisions.

9. Use adaptive management for achieving desired outcomes and better understanding of ecosystemconditions—adaptive management provides confidence when environmental decision-making mustproceed in the presence of uncertainties.

aSource: modified from US MAB (1994) and Harwellet al. (1996).


Risk-based framework

Ecological risk assessment is the process of evaluating the likelihood that adverse ecologicaleffects occur as a result of exposure to one or more stressors. The ecological risk assessmentframework provides a systematic methodology for identifying, organizing, and analyzingdiverse environmental information to produce a qualitative or quantitative statement thatassesses the magnitude and probability of adverse effects. A fundamental attribute of thisframework is the incorporation of societal values and preferences into a goal-setting pro-cess that results in the identification of one or more ecological endpoints that become thefoundation of the assessment.

Key to making the appropriate links between science and the decision-making processare the relationships among goals, endpoints, and measures of system condition (figure 2).It is up to society to decide its environmentalgoals, that is, what ecological conditions aredesired for a region and its constituent subregions. This is the first principle of ecosystemmanagement, in which society and the scientific community mutually establish a vision ofwhat specific ecological conditions are desired for each part of the landscape. In the caseof South Florida, the Governor’s Commission for a Sustainable South Florida constituteda unique societal institution designed explicitly to develop such sustainability goals for theentire region. While the development of environmental goals is primarily the responsibilityof society, these goals need to be scientifically constrained, i.e., sustainability goals for thehuman and environmental systems must be consistent with the nature of those systems asunderstood by science (Ecosystem Management Principles 2, 6).

If goals and objectives are identified appropriately, they would capture the consen-sus among the stakeholder representatives and would be substantively informed by the

Figure 2. Relationship between societal goals and scientific endpoints and measures. Reprinted from Harwellet al. (1999).

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understanding of the scientific community. The goals and objectives, in turn, become thebasis for exploring with scientists the possible alternative management structures and poli-cies that might achieve these desired goals, including assessing the implications of themanagement alternatives as they would affect subregions differentially.

Once goals are established, the next issue is the selection ofendpoints(figure 2), i.e.,the identification of those ecological and human system attributes that can be used tocharacterize the health of the system (Gentileet al., 1993; Kelly and Harwell, 1990; USEPA, 1992). Endpoints are selected based on their ecological importance (e.g., ecologicalprocesses, critical species) or societal importance (e.g., economic or aesthetic species, urbanwater supply, flood protection) and should cut across species, ecosystem, and landscapescales. Ideally, a parsimonious set of such endpoints should be developed, so that a changein an endpoint would constitute a change in the health of the human/environment systemthat people would care about, and, conversely, a change in the health of the system wouldshow up in one or more endpoints. Consequently, selection of endpoints is both a scientificand a societal task, but once the endpoints are selected, what is actuallymeasuredis ascientific issue, requiring an environmental and societal monitoring program to quantifythe selected endpoints.

In a goals-driven process, then, an institution, such as the Governor’s Commission, definessocietal goals and objectives, and a scientific process translates those goals and objectivesinto ecologically meaningful endpoints and measures. These endpoints and measures be-come the basis for evaluating the health of the ecosystem and, consequently, assessingwhether the societal goals and objectives are being attained.

Science-based strategic process

A science-based strategic process was proposed by the US MAB project to implementthe ecosystem management and risk-based frameworks for understanding the linkages anddistinctions among goals, endpoints, and measures for South Florida (figure 3). The purposeof this strategic process was to strengthen the role of science in the planning, implementation,and evaluation of the South Florida ecosystem restoration. Note that whereas the graphicappears linear, the process must be iterative, with multiple opportunities for feedback andrefinement.

Entry to the process is the delineation of the societal goals, discussed above. However,to translate societal goals to specific management plans requires the development ofcon-ceptual modelsthat demonstrate the causal relationships among societal drivers, resultingenvironmental stressors, and their effects on human and ecological systems. Thus the con-ceptual model should incorporate the full scientific understanding of how the human andenvironment systems work at the regional and subregional scales, and across ecologicalsystem types (e.g., sawgrass to seagrass, uplands to estuaries, wilderness to urban areas).

Typically the conceptual model derives from historical, empirical, modeling, and moni-toring information, and can be either a qualitative or a quantitative synthesis of the state ofscientific understanding. Moreover, the conceptual model should include all of the endpointsthat characterize the system condition, and it should provide a graphical representation ofconnectivity from management actions to ecological health. Thus, the conceptual model


Figure 3. The strategic process for linking science and the environmental decision-making process. The restora-tion goals set by society are translated into specific restoration plans through the development of scientific concep-tual models and hypotheses about how anthropogenic activities affect ecosystems. Once the system modificationsare made and the systems respond, an evaluation of the health of the ecosystem provides feedback for an adaptivemanagement process. The concept of an ecosystem health report card for scientists and decision makers is shown,with feedback from scientific studies to reduce uncertainties and improve the understanding of the ecosystems.

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generally includes the following elements: (1) a clear delineation of the spatial, temporal,and ecological scales and boundaries; (2) a description of the potential stressors and theirsources; (3) direct and indirect exposure pathways of multiple natural and anthropogenicstressors; (4) information on the cooccurrence between exposure pathways and humanand/or ecological receptors; (5) a series of hypotheses describing the full spectrum of po-tential system effects; and (6) a critical examination and ranking of the hypotheses in orderof importance based on both empirical data and/or professional judgment.

The ultimate intent of the conceptual model is to develop a suite of testable hypothesesthat describe the full spectrum of potential ecological effects for a specific problem setting.These hypotheses become the basis for restoration plans by defining the structural and op-erational modifications of the system that are necessary to achieve the desired sustainabilitygoals and by providing the causal linkages for developing performance criteria. The lattercan be descriptive or numerical targets for managing the critical stressors (e.g., hydrology)shaping the system’s ecology. Once the management plans are implemented, and the eco-logical and human systems respond to those modifications, then the system responses mustbe monitored in order to assess progress towards sustainability goals (Ecosystem Manage-ment Principle 9). This provides the scientific foundation for (a) testing the validity of theconceptual model and hypotheses; (b) reducing scientific uncertainty; (c) identifying newresearch activities; and (d) modifying restoration actions (i.e., adaptive management).

The US MAB project strategic process for the South Florida environmental restoration(figure 3), discussed above, was proposed to the South Florida Ecosystem Restoration TaskForce, which established a series of working groups to develop conceptual models foreach major ecological and societal system in the region. The ecological conceptual modeldevelopment process resulted in selection of endpoints and measures for each ecosystemtype and subregion, identification of the natural and anthropogenic stressors affecting eachecosystem, and pathways of how stressors affect the selected endpoints. These ecologicalconceptual models, in turn, provided a basis for examining the potential consequences ofvarious management options under consideration by the Restudy process in the developmentof its draft Proposed Plan (discussed below). The conceptual models also provide a basis forprioritizing research activities to focus on those areas of greatest uncertainty and greatestimportance to understanding the ecological systems and how they would respond to newmanagement systems.

An example of a conceptual model developed by the strategic process is the ecologi-cal conceptual model of the Biscayne Bay ecosystem (figure 4). Note that the societaldrivers and anthropogenic stressors, which are inputs at the top of the ecological conceptualmodel, are derived as the outputs from the societal conceptual model (C. Harwellet al., thisvolume).

Scientific report card

Once the management policies are implemented, evaluations of system performance shouldbe developed as regional and subregionalreport cards(Harwellet al., 1999). Report cardsare essential to characterize for scientists how the ecosystems are responding comparedwith expectations, and to characterize for decision makers and the public how well the


Figure 4. Conceptual ecosystem model for the Biscayne Bay ecosystem. Biscayne Bay is down-stream ofhydrologic changes associated with proposed Everglades restoration plans and thus subject to changes in surfaceand ground water inputs to the Bay. The ovals represent anthropogenic stressors on the environment resultingfrom the societal driver of water and land use changes. The small diamonds represent mechanisms of causalrelationships between the stressors and ecological effects, and the large diamonds represent the major ecologicaleffects. The hexagons represent the ecological endpoints selected for this ecosystem to reflect the ecological effects.Each ecological endpoint would have one or more specific measure associated with it. This conceptual model wasdeveloped by the Biscayne Bay conceptual model team, led by Wendell Cropper and Diego Lirman of the Universityof Miami and Beth Irlandi of the Florida Institute of Technology. Unpublished manuscript.

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investment in restoration is working. These scientifically based report cards should beginat the measurement and endpoint levels, and through a systematic process of aggregationfrom these levels, a separate public/decision makers’ report card should be developed thatdescribes progress towards overall and subregional sustainability goals. While the US MABproject developed the framework for such an ecosystem health report card, this phase of thestrategic plan has yet to be implemented for the South Florida ecosystem restoration.

Development of South Florida ecosystem management plans

Over the past few years, three increasingly detailed scenarios or plans have been developedfor ecosystem management of South Florida, following the general construct of figure 3.The first was created by the US MAB project (Harwellet al., 1996) through the developmentof a set of alternative scenarios for the future of the region. The US MAB project scenariosvaried by the amount and nature of acquisition of public and private lands for coordinatedmanagement with particular attention to hydrological issues. The objective of the scenarioswas to create a water management regime that met the goal of restoration and sustainabilityof the ecological systems while maintaining water supply and flood protection needs ofsociety.

The US MAB project Scenario C (figure 5) captured the elements that scientists believedwere critical in achieving this goal by focusing on the essential ecological characteristics ofthe Everglades. Those essential ecological characteristics were identified as providing for(a) the large spatial extent of the landscape; (b) dynamic storage of water, with sheetflowof low-nutrient water following historical seasonal-to-interannual variability; and (c) long-term sustainability of the EAA agricultural system in recognition of the benefit to the naturalecosystems of retaining agriculture and excluding urban development in the upper portionof the Everglades.

Elements of the US MAB project scenario included (1) creating new surface waterstorage areas in the lower part of the EAA to store excess freshwater for subsequent releaseinto the Everglades; (2) converting some areas in the EAA to agriculture in presence ofhigher water levels (e.g., new cultivars of sugar, more rice production), including creativeeconomic incentives for compensation of farmers if yields are decreased; (3) developingthe capacity for water storage either in underground facilities or in historical wetlands; (4)redirecting or storing significant quantities (estimated on the order of 1.2×109 m3 per year)of freshwater currently being diverted through canals to the Caloosahatchee and St. Lucieestuaries; (5) removing levees, canals, and other structures to allow sheetflow of freshwateracross the core area of the Water Conservation Areas and the Everglades National Park; (6)creating structures adjacent to the boundaries of the Everglades and urban areas to reducegroundwater seepage; and (7) altering the management of Lake Okeechobee to achieveecological goals for that ecosystem (Harwellet al., 1996).

These scenarios helped guide the scientific analyses and crystallize the assessments of theimplications of management options. The historical and current ecological and hydrologicalconditions of the region, as assessed by the US MAB project, are discussed in Browder andOgden (this volume) and Obeysekeraet al. (this volume), and the ecological implications tothose systems of the US MAB project scenario are discussed in Ogdenet al. (this volume).


Table 2. Ecosystem goals and objectives developed by the Governor’s Commission for a Sustainable SouthFloridaa.

Goal I—Restore key ecosystems—to restore the Everglades and associated ecosystems of South Florida to provideadequate supplies of clean, safe water for natural, human, and economic systems.

Objective I-1 Restore more natural hydropatterns, including sheetflow

Objective I-2 Provide more natural quality and quantity, timing, and distribution of freshwater flow

Objective I-3 Provide the spatial extent of natural areas to support the mosaic habitat characteristic of thepredrained Everglades ecosystem

Objective I-4 Regain lost water storage capacity

Objective I-5 Restore and enhance regional groundwater storage

Objective I-6 Restore and improve functional quality of natural systems (including both wetlands and uplands)

Objective I-7 Restore more natural marl soil formation processes and arrest soil subsidence

Goal II—Protect wildlife and natural areas—to provide sufficient open space to protect wildlife and to providenatural and recreational areas for public use.

Objective II-1 Reduce the spatial extent of invasive nonnative species so that they do not affect the naturalsystem

Objective II-2 Halt and/or reverse the spread of native species that result from disturbances such as nutrientenrichment

Objective II-3 Provide for sustainable populations of native plant and animal species with attention to threatenedand endangered species and species of special concern

Objective II-4 Improve and protect habitat quality, heterogeneity, and biodiversity

Objective II-5 Improve connectivity and reduce habitat fragmentation

Goal III—Achieve a more clean, healthy environment—to prevent and reverse pollution in South Florida’s air,land, and water.

Objective III-1 Improve water quality consistent with designated uses including restoration and protection ofthe natural systems

Objective III-2 Control saltwater intrusion into freshwater aquifers

Objective III-3 Enhance pollution prevention measures

Objective III-4 Improve regional air and water quality for wildlife, humans, and the environment

aSource: Governor’s Commission (1996). Modified from Harwellet al. (1999). The commission reached con-sensus on a diversity of ecological and societal goals; shown here are the ecological goals and the more specificobjectives associated with each goal.

The current and historical human systems of South Florida, as assessed by the US MABproject, are discussed in Soleckiet al. (this volume), and the societal implications of theUS MAB project scenario are discussed in C. Harwellet al. (this volume).

The US MAB project study was presented to the Governor’s Commission in 1994 toencourage the commission to adopt an ecosystem management approach as it began itsdeliberations on sustainability goals and objectives. The Commission subsequently didfollow the principles of ecosystem management in its deliberations. Over a period of manymonths, the Commission reached consensus and articulated a set of goals and objectives forthe ecological and societal sustainability of the region (Table 2) (Governor’s Commission,1996). These goals constitute the best representation of societal goals for the region and

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provide a unique foundation for developing and evaluating the restoration process for SouthFlorida.

The other input to the Governor’s Commission from the US MAB project was its scenarioas a point-of-departure for the Commission to develop its own plan. The Governor’s Com-mission subsequently developed its Preferred Alternative Plan (Governor’s Commission,1996; Harwell, 1998) through close interactions among the Commission, the Restudy team,and several scientific and technical advisory groups. Using the goals and objectives as thecriteria for accepting or rejecting options, the Commission made many difficult decisionswhen selecting from a large number of potential management options. Again, this PreferredAlternative captures a breadth of societal considerations about a sustainable human andecological system for South Florida.

The Governor’s Commission Preferred Alternative (Governor’s Commission, 1996) isshown in figure 6. Elements of the Commission’s plan are quite similar to those of the USMAB project scenario, with the addition of the following: (1) further resolution of specificgoals and objectives for the region; (2) increased attention to restoration of significantlydisturbed wetlands in southwest Florida and southern Miami-Dade County; (3) incorpo-ration of the additional concept of underground storage of water in Aquifer Storage andRecovery (ASR) systems distributed across the region; (4) development of seepage controlmechanisms, such as underground walls along the boundary of the Everglades and urbanareas; and (5) creation of multipurpose Water Preservation Areas for water storage andtreatment, wetlands enhancement, seepage control, and other functions.

The commission delivered this Preferred Alternative plan to the Corps as it began itsfinal process in the Restudy to develop the plan to be recommended to Congress. Un-der the auspices of the South Florida Ecosystem Restoration Task Force, a series ofworking groups were created to develop conceptual models of many different ecosys-tem types (e.g., Biscayne Bay conceptual model discussed above, as well as many otherconceptual models for Florida Bay, the Kissimmee River, the marl prairie/rocky glades,the sawgrass-slough ecosystem, and other ecosystems). These conceptual models, whichwere developed following the ecological risk assessment framework, provided a mecha-nism to reach scientific consensus on the essential ecological characteristics, ecologicalendpoints, primary stressors, and pathways for stress–effect relationships for each ecosys-tem in the region. These conceptual models then became an important tool for assessingthe implications of potential management scenarios that were explored as a part of theRestudy.

The US ACOE Restudy team, along with the South Florida Water Management District,developed models to simulate the hydrological system of South Florida and to project thehydrological conditions that would ensue from various management options. Using theGovernor’s Commission’s Preferred Alternative, as well as the Commission’s goals andobjectives for guidance, the Restudy team simulated the ecological and other consequencesof a large number of specific management options. They also conducted a series of sen-sitivity analyses in order to create a comprehensive draft plan for restructuring the C&SFsystem. The Corps’ Draft Recommended Plan (US ACOE, 1998; www.restudy.org) fol-lows essentially the same objectives and elements as the US MAB project and Governor’sCommission’s plans (Governor’s Commission, 1998) but has taken them to the next level

Figure 5. Ecosystem management scenario developed by the US MAB Project. Redrawn from Harwellet al.(1996).

Figure 6. Schematic representation of the Governor’s Commission preferred alternative plan. Modified fromGovernor’s Commission (1996) and reprinted from Harwell (1998).


Table 3. Elements of Corps of Engineers’ draft recommended plana.

Develop surface water storage reservoirs—A number of water storage areas are proposed north of Lake Okee-chobee, in the Caloosahatchee and St. Lucie river basins, in the Everglades Agricultural Area (EAA), and inthe western areas of Palm Beach, Broward, and Miami-Dade Counties. Water will also be stored in limestonequarries surrounded by underground wall to reduce groundwater leakage.

Develop underground water Storage—A large number of well-injected underground storage areas, known asAquifer Storage and Recovery (ASR), will be created around Lake Okeechobee for temporary storage ofwater and to reduce losses from evapotranspiration.

Create water preserve areas—These multipurpose areas will treat urban runoff, store water, reduce groundwaterseepage, and enhance existing wetlands; they are to be located between the urban areas and the easternEverglades.

Manage Lake Okeechobee as an ecological resource—The lake is currently managed in inconsistent and con-flicting ways, so new management rules are proposed to enhance the ecological condition of Lake Okeechobeeand to integrate its management with the management of the Everglades.

Improve water deliveries to estuaries—Presently, extreme releases of freshwater to the Caloosahatchee and St.Lucie Rivers adversely affect their estuaries; the recommended plan will greatly reduce these discharges bystoring water in surface or underground storage for subsequent release during periods of low flows.

Establish water treatment wetlands—In addition to the 162 km2 of artificial wetland treatment areas currentlybeing built in the EAA, the plan proposes an additional 121 km2 of stormwater treatment areas locatedthroughout the system to be built for treating runoff being discharged to the natural areas. Advanced wastewatertreatment systems have also been proposed for wastewater reuse in coastal wetlands.

Establish more natural surface water flows—Changes will be made to the C&SF to allow more natural sheetflowacross the landscape with more natural timing.

Improve freshwater water deliveries to Florida Bay and Biscayne Bay—The recommended plan will enhancethe quantity and timing of freshwater runoff into these two coastal ecosystems.

aSource: Modified from US ACOE (1998).

of specification of the particular engineering modifications needed. The elements of theCorps’ draft Recommended Plan are listed in Table 3 and illustrated in figure 7.

Next steps in the ecosystem management process

The US ACOE Restudy process continues, with the final Proposed Plan submitted to the USCongress in July 1999, along with a request for authorization of funds to modify the C&SFProject. In the interim, a series of public hearings and revisions were scheduled. The Gov-ernor’s Commission and Task Force also continue to provide coordination and input tothe Restudy. The US MAB Human-Dominated Systems Directorate, which conducted theSouth Florida case study as its core project from its inception in 1990, has reached thescheduled completion of the project and has now been disbanded. At present, US MAB isin a period of transition, and it appears unlikely that it will support future interdisciplinaryresearch projects such as this one.

One important activity that remains unfinished is the development of the ecosystemhealth performance evaluation or report card using the US MAB project report card frame-work (Harwellet al., 1999). The next steps in the process include developing (a) the specificstructure of the South Florida ecosystem health report card, including the suite of ecological

218 HARWELL ET AL.

Figure 7. Graphical representation of the US ACOE draft recommended plan. Modified from US ACOE (1998);www.restudy.org.


endpoints and measures, based on the conceptual models for each ecological system type inthe region; (b) a monitoring program to track each measure over specified time intervals; (c)the algorithms for aggregating the data collected for each measure into values assigned foreach endpoint; (d) the methodology for aggregating the status of the ecological endpointsinto an assessment of the overall ecological condition vis-`a-vis the societal goals and objec-tives for South Florida; and (e) once the restoration plans are approved and implemented,collecting the specified environmental data through the monitoring program, performingthe aggregations, and issuing periodic performance evaluations of the progress towards theecological sustainability goals.

Implementation of the final C&SF plan is expected to take at least two decades onceit is approved by Congress (US ACOE, 1998). Because of inherent response time lags inecological systems in general, and the importance of interannual variability in the health anddynamics of the South Florida ecosystems in particular, it will take many additional yearsto implement the report card process to the point where scientifically sound, comprehensiveassessments of the efficacy of the management changes can be performed. The challengesand opportunities in South Florida include finalizing an ecosystem management plan thatsustains societal support for funding over the long term, establishing an effective monitoringand performance evaluation process, and actually implementing an adaptive managementapproach to managing the regional environment for sustainability of both ecological andsocietal systems.

Acknowledgments

This article is contribution number US MAB HDS 051 of the U.S. Man and the Biosphere(US MAB) Human-Dominated Systems Directorate (HDS) Series.

Funding for this study was provided, in part, by the US MAB Program (Grant #1753-100110). US MAB is administered by the U.S. Department of State as a multiagency,collaborative, interdisciplinary research activity to advance the scientific understanding ofhuman/environment interactions. Additional funding was received from the U.S. ArmyCorps of Engineers, Waterways Experiment Station, Vicksburg, MS (Contract #DACW39-94-K-0032) and the U.S. Department of Commerce/National Oceanic and AtmosphericAdministration (NOAA) through a UM/NOAA joint research project funded by the NOAACoastal Ocean Program as part of the University of Miami-NOAA Cooperative Institute forMarine and Atmospheric Studies (CIMAS NA67RJO149: Task 3 Coastal Ocean EcosystemsProcesses). This article does not necessarily represent the policies of US MAB, the U.S.Department of State, any member agency of US MAB, the U.S. Army Corps of Engineers,or the U.S. Department of Commerce/NOAA.

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