Given the enormous scope and complexity of the restoration effort, strategic, high-quality, responsive, and sustained science and adaptive management are needed to ensure the effectiveness of the impressive Comprehensive Everglades Restoration Plan (CERP) engineering efforts under way. In this chapter, the committee reviews scientific support for Everglades restoration from several perspectives. This chapter builds upon prior reviews of this topic by the National Research Council (NRC, 2007, 2008, 2010, 2012a). First, science coordination and management are discussed, with particular emphasis on what is needed for an effective, sustainable systemwide monitoring program. Next, progress on the implementation of adaptive management is discussed. Finally, the recently released 2014 Draft System Status Report (RECOVER, 2014a) and the Science Plan for Everglades Stormwater Treatment Areas (SFWMD, 2013d) are reviewed, because they represent important contributions to the adaptive management process.
SCIENCE COORDINATION AND MANAGEMENT
A comprehensive program of scientific research and systemwide monitoring helps ensure that the substantial investment in Everglades restoration is being directed effectively. Moreover, the concept of adaptive management depends on monitoring data to assess whether restoration goals and targets are being met and on lessons learned through scientific research to improve restoration outcomes. Because of the complex nature of the Everglades ecosystem and the numerous federal, state, and tribal government agencies and stakeholders involved with multiple perspectives and objectives, science governance is a challenge. To have a robust effective science and monitoring program for this complex restoration program, a number of features are required, including stable funding and effective science coordination and communication. The committee judges that research support for Everglades decision making is robust; therefore, this section focuses on monitoring and coordination.
The Need for Robust Science and Monitoring Programs
Substantial federal and state resources have been and continue to be invested in Everglades restoration. To ensure that these resources are being used wisely to achieve restoration objectives, a robust science and monitoring program is essential. Scientific research provides knowledge and tools that assist decision makers. Monitoring involves the collection of data necessary to evaluate the success of various restoration projects. Long-term data that describe the conditions, variability, trends, and patterns related to resources and processes in the Everglades are fundamental to understanding whether and how projects, once implemented, change conditions. Systemwide, long-term perspectives are all the more important in the context of climate change, given that “baseline” (pre-project) conditions are not anticipated to be stationary through time (see Chapter 5). Comprehensive ongoing monitoring and assessment are also critical to adaptive management.
The importance of comprehensive monitoring and assessment to the success of Everglades restoration has been recognized from the beginning by CERP partners and by prior NRC committees (NRC, 2003a, 2007). Under RECOVER, a systemwide Monitoring and Assessment Plan (MAP) was developed as “a single integrated, system-wide monitoring and assessment plan that will be used and supported by all participating agencies and tribal governments as the means of tracking and measuring the performance of the CERP.”1 The most recent is the 2009 MAP (RECOVER, 2009), which is a revised version of MAP 2004 (RECOVER, 2004). The RECOVER program is responsible for linking science with CERP systemwide planning, evaluation, and assessment, and one key RECOVER responsibility is to “ensure that a system-wide perspective is maintained through the restoration process” (RECOVER, 2012a). The RECOVER program uses scientific information developed pursuant to implementation of the MAP to assess the performance of the CERP.
Beginning with a dedicated workshop in November 2001, the NRC has reviewed the development of MAP and the selection of appropriate and practical performance measures by RECOVER (NRC, 2003, 2007, 2008, 2010). As noted in NRC (2008), performance measures of both ecosystem condition and critical ecosystem stressors (e.g., estuarine salinity, soil and water phosphorus concentrations, hydropatterns) have been developed, which allows assessment of cause-effect relationships. This is a great strength of the performance measure system, because an understanding of ecosystem dynamics is crucial for implementing an adaptive management approach. The MAP and its performance measures were reviewed extensively in NRC (2008), which concluded that “[t]he number of performance measures is not inherently problematic” but noted that
“the set of performance measures should be reviewed regularly to determine whether … adequate data collection for each could be sustained over the course of the restoration.”
Previous NRC reports (2003a, 2007, 2010) have judged that the RECOVER MAP is a reasonable plan for monitoring and assessing systemwide conditions in the Everglades. The team that developed the MAP seems to have taken a holistic view and does not appear to have been overly influenced by parochial interests. The MAP does not narrowly focus on specific projects, specific geographic areas, or specific resources, but instead takes a systemwide approach. However, there are several shortcomings with the MAP. From the beginning, the MAP was intended to fill critical gaps in systemwide monitoring, rather than to control and fund all restoration-related monitoring for the Everglades. The challenge with this approach is that no entity oversees the entire monitoring effort or manages monitoring priorities across a diverse array of agencies and institutions. Thus, it would be helpful to have a process to evaluate and revise the MAP over time as agencies’ funding changes.
A recurring, comprehensive review process would also help the MAP adapt as new information becomes available and as ecosystem conditions change due to climate change or other anthropogenic or natural circumstances. Given the extremely long time lines currently being projected for completion of the Central Everglades Planning Project (see Chapter 3) and the very real likelihood that climate change and sea-level rise will cause significant changes to the South Florida ecosystem during this time (see Chapter 5), the MAP should be revisited to evaluate whether it is still appropriate. Key long-term monitoring to understand the shifting ecological baselines in the context of climate change may currently be overlooked, while other monitoring may be too frequent in the context of the slow pace of CERP implementation.
The Need for Stable Funding
The most significant shortcoming with the MAP, however, is not necessarily with the plan itself, but with the implementation of the plan, because of substantial funding cuts that have occurred in the past few years and the overall funding structure. A dedicated, stable, and reliable funding source is essential to obtain the long-term systemwide monitoring data necessary to evaluate the success of restoration efforts. Such funding is necessary to conduct monitoring for long enough to provide a scientifically sound understanding of the conditions, trends, and patterns for each parameter of concern.
NRC (2012a) addressed the recent budgetary cuts and their impact on monitoring and assessment. In that report, the committee concluded that the
large and sudden cuts to the RECOVER MAP pose a risk to systemwide assessment, which is important to the success of Everglades restoration. The cost of the RECOVER-funded monitoring through the MAP increased from about $0.7 million in fiscal year (FY) 2000 to about $10 million in FY 2007, and MAP funding has declined roughly 60 percent since 2007, with a sharp cut of 48 percent in FY 2012 (NRC, 2012a). The funding level has remained flat throughout 2013. These cuts were amplified by cuts in many other agencies’ monitoring budgets. Agency staff voiced concerns that the monitoring cuts reduced the capacity to understand systemwide ecosystem responses and to explain why changes may have occurred.
Although the CERP is struggling with many budget uncertainties, the committee remains convinced of the vital importance of systemwide monitoring to the success of Everglades restoration. Without a sufficient monitoring program, the CERP cannot be accountable to federal or state sponsors and cannot support its adaptive management program. The committee recognizes the realities of changed economic conditions, budgets cuts, and shifting priorities and thus understands that funding cuts sometimes are unavoidable. But the long-term costs of monitoring cuts are often overlooked. If funding cuts result in significant gaps in critical long-term monitoring data, important changes and patterns could be missed, and data collected prior to or after the gaps created by funding cuts could lose their value. Therefore, to ensure that existing monitoring is cost-effective and provides adequate support for CERP planning, adaptive management, and public communication, a comprehensive review of all monitoring programs that were considered in the original design of the MAP is needed, considering recent and projected reductions. The major MAP budget reductions for FY 2012 were implemented very quickly (NRC, 2012a), and time was not available to reconsider the essential components of a monitoring program, particularly in light of the slow pace of CERP implementation in a changing climate, or to consider the shifting budgets of other agency monitoring programs.
The existing monitoring funding structure with its 50-50 state-federal cost-sharing requirement (see Chapter 4) appears to be especially vulnerable to changing economic and political conditions. The structure of the cost share is such that if the state experiences cutbacks that result in funding cuts to the MAP, the federal government may be constrained from making up the differences to fund the MAP because such funding will heighten imbalances in the overall cost share. A different funding structure that not only provides a more reliable, consistent long-term source of support could go a long way in ensuring continuity in long-term monitoring. Although there may be a wide range of possible mechanisms for providing long-term stable funding for ecosystem-wide monitoring and assessment, one approach could be dedicated funding provided
to one federal agency without being tied to the 50-50 cost-sharing requirements of the current system.
The Need for Effective Coordination and Communication
Scientific research and monitoring programs require coordination and communication to be effective and efficient. Currently, there is no single entity that is responsible for coordinating scientific study and scientific monitoring related to restoration. Numerous federal and state agencies, as well as other entities such as tribes, local governments, nongovernmental organizations, and universities carry out research projects and monitoring related to restoration. In fact, in the last few years, at least 50 scientific studies have been conducted in the Everglades. Many of these studies are either agency specific or project specific. In other words, each agency carries out studies to support its own responsibilities and objectives. For example, the National Park Service, the U.S. Geological Survey, and the South Florida Water Management District (SFWMD) each conduct research related to its agency missions and objectives. These research efforts may focus on specific resources or specific geographic locations or may have systemwide applications.
After the U.S. Government Accountability Office (GAO, 2003) recommended improved science coordination, the South Florida Ecosystem Restoration Task Force’s (Task Force’s) Science Coordination Group (SCG) developed the 2006 Plan for Coordinating Science (SFERTF, 2006), last updated in 2010 (SFERTF, 2010). The Department of the Interior released its Science Plan in Support of Ecosystem Restoration, Preservation, and Protection in South Florida in 2005 (DOI, 2005). However, these plans are now dated, and no longer serve to facilitate scientific coordination.
The SCG was specifically formed to coordinate the scientific aspects of restoration to support the efforts of the Task Force. SCG members include both scientists and senior managers from federal and state agencies, tribes, and local governments. The purpose of including both scientists and senior managers in the SCG is to “enhance the integration of science and management” (SCG, 2003). The SCG is charged with coordinating the scientific aspects of restoration in general and thus is not limited to CERP projects or monitoring. Despite the broad science coordination charge to the SCG, the group’s success in providing coordination and oversight of science has been limited. Ideally, an organization such as the SCG, broadly tasked with science coordination, would keep track of ongoing scientific studies, identify gaps and redundancies, identify scientific needs, and direct staff and financial resources to fill significant information gaps. It does not appear that the SCG has played a significant role since 2006 in
evaluating the state of the science to identify gaps or overlaps. It is not entirely clear why the SCG has not played a more significant role. The SCG’s lack of dedicated funding and lack of authority to direct financial resources to pay for needed science certainly is part of the limitation. For the SCG to significantly contribute to better science coordination, it would need to have adequate funding and staff and a clear charge to address critical science needs from a restoration-wide perspective.
The history of the SCG suggests that its role and priorities have shifted over time. These shifts may be contributing to the perceived diminution of science coordination or may be the result of other actions such as cuts to science budgets or personnel changes. In any event, a review of the role of the SCG over the past 10 years may provide some insight that could inform efforts to improve science coordination and communication.2 In the first few years after its formation in 2003, the SCG appears to have been intensely focused on developing its comprehensive Plan for Coordinating Science and developing systemwide indicators. Both were original efforts that required intense staff and SCG member engagement and creative work. In 2007-2008, the SCG continued working on a science coordination plan and systemwide indicators while beginning to tackle some challenging questions in focused meetings or workshops (e.g., identifying ecosystem features or areas with the largest rates of decline, potential impacts of climate change). In 2009-2011, the SCG shifted its focus to new initiatives related to climate change, invasive species, and new science. Although these efforts were intended to be original syntheses to assist the Task Force in identifying next steps, the actual impact of these efforts is not clear. During this time, the SCG also held a workshop on science and decision making, which was well received. Since 2011, the SCG meetings have discussed the Central Everglades Planning Project and MAP budget issues. Although there was discussion of a workshop to reevaluate the monitoring plan,3 such a workshop has not yet occurred. It also appears that during the past few years, the number of SCG meetings has tapered off and the meetings have been focused more on providing restoration updates, rather than unique SCG initiatives. The extent to which recent budget cuts and the recent intense focus on the Central Everglades Planning Project has diverted attention from science coordination is unclear. In any event, it seems clear to the committee that the SCG could and should reengage in its mission of science coordination and leadership. An important task for the SCG would be a comprehensive reevaluation of restoration-related monitoring in light of current budget impacts, the extended CERP implementation time frames, and
climate change. This reevaluation should clearly articulate the value of the highest priority monitoring needs and the risks of ceasing such monitoring to future restoration decision making. One important component of carrying out these recommendations would be for the SCG to hold regular meetings focused on science coordination planning and for the SCG to host occasional workshops on important science-related issues.
Another issue that has been raised with regard to science governance is the challenge of communication between scientists and upper-level managers and policy makers. A communication structure that facilitates communication between scientists and upper-level management is fundamental to sound decision making. Managers need a mechanism to communicate information needs to researchers to meet policy objectives. Researchers also need a mechanism that enables them to communicate science needs and results of research and monitoring to upper-level management. One process that could be put into place is a regular meeting between senior science staff and upper-level managers to discuss the status of ongoing science and how it relates to decisions being made at high levels. It does not appear that this type of meeting between scientists and high-level managers occurs with any regularity. If the SCG revisited the comprehensive 2006 Plan for Coordinating Science, the SCG could facilitate discussions between policy makers and scientists to identify additional pressing science needs.
In the context of the CERP, adaptive management is defined as “a structured management approach for addressing uncertainties by testing hypotheses, linking science to decision making, and adjusting implementation as necessary to improve the probability of restoration success” (USACE and SFWMD, 2011b). A major characteristic of adaptive management is a feedback mechanism for refining project planning and implementation based on new information gained from monitoring results, thus reducing uncertainties that may prevent a project from proceeding or achieving its intended outcomes. Adaptive management has been a core component of the CERP since the year 2000 and remains an active and continually evolving area of planning. Previous NRC reports have provided detailed reviews and evaluations of the adaptive management principles and frameworks developed for the CERP in terms of their ability to meet adaptive management goals and assess restoration outcomes (NRC, 2008, 2010). In this section the committee reviews the progress made in activities to support adaptive management within the CERP since 2010. A more detailed review of adaptive management progress in the context of the Central Everglades Planning Project is provided in Chapter 3.
In the CERP Monitoring and Assessment Plan (RECOVER, 2004, 2006a, 2009) monitoring and research needs are identified for measuring ecosystem responses to CERP implementation, but the first authorized CERP projects did not include formal adaptive management plans. Although the Water Resources Development Act of 2000 acknowledged the adaptive management foundations of the CERP, the 2003 Programmatic Regulations (33 CFR Part 385) required development of an adaptive management program by CERP-implementing agencies, and the 2006 Comprehensive Everglades Restoration Plan Adaptive Management Strategy (RECOVER, 2006b) laid a framework for adaptive management, it was not until 2009 that the U.S. Army Corps of Engineers (USACE) required adaptive management plans for all USACE ecosystem restoration projects (Convertino et al., 2012; LoSchiavo et al., 2013). Since 2009, formal adaptive management plans have been developed or revised for four CERP projects (Table 7-1): Decompartmentalization of Water Conservation Area 3 (WCA-3), the Biscayne Bay Coastal Wetlands project, Broward County Water Preserve Area, and Central Everglades Planning Project (USACE and SFWMD, 2011c, 2012c,e, 2013b). The C-111 Spreader Canal also has a monitoring and assessment plan (USACE and SFWMD, 2011d) that contains many components of an adaptive management plan despite lack of formalization and approval as an adaptive management plan (Table 7-1). These plans contain various levels of complexity, dictated in part by the scope of the project and the suite of desired ecosystem responses with project implementation. Additionally, adaptive management options are limited if they are not integrated into the project design from the outset—the initial phases of the CERP did not explicitly integrate adaptive management into project implementation plans because it was not mandated. Hence, since 2009, adaptive management plans have become more integrated and sophisticated with time as guidance has been developed and refined, with the Central Everglades Planning Project adaptive management plan being the most complex and sophisticated to date (see Chapter 3).
Two notable sets of guidelines have recently been finalized with the aim of providing an explicit framework for developing consistent adaptive management plans for CERP projects: the Adaptive Management Integration Guide (RECOVER, 2010), and the CERP Guidance Memorandum 56 (USACE and SFWMD, 2011b). The CERP Guidance Memorandum 56 is the first guide to merge the various adaptive management documents with other guidance memoranda for development of project implementation reports (PIRs). It specifically focuses on areas of intersection in adaptive management guidance across the CERP 6-step planning process, the Adaptive Management Integration Guide, the USACE Planning Guidance Notebook (USACE, 2000), engineering circulars and regulations, and USACE Headquarters guidance memoranda. These two
TABLE 7-1 Time Line of Inclusion of Adaptive Management Plans in Active CERP Projects
|CERP Project||Current USACE Life-Cycle Phase (year authorized)||Adaptive Management Plan||Adaptive Management Features|
|Aquifer Storage and Recovery||Pilot projects implemented (2000 authorization)||Noa||Testing pilot projects and sensitivity modeling|
|Indian River Lagoon-South||Construction (2007 authorization)||No|
|Picayune Strand||Construction (2007 authorization)||No||Monitoring and assessment plan with recommendations to use adaptive management|
|Site 1 Impoundment||Construction (2007 authorization)||No|
|Melaleuca eradication||Implementation (2007 authorization)||Noa||Adaptive management implementation strategy and some monitoring|
|2009 USACE HQ policy requiring adaptive management for ecosystem restoration projects; 2011 CERP Adaptive Management Integration Guide and 2011 CERP Memorandum Guide 56 released|
|C-111 Spreader Canal||Pilot project and Planning Chief’s report (2011), operations||Noa||Design and operational tests, project phasing|
|Decompartmentalization of WCA-3||Pilot project constructed (2013)||Yes||Decomp Physical Model adaptive management field test|
|Biscayne Bay Coastal Wetlands||Planning Chief’s report (2012)||Yes||Post-construction management options matrix and linked monitoring|
|Broward County Water Preserve Areas||Planning Chief’s report (2012), design||Yes||Operational options linked to nutrient and ecological monitoring, and design improvements|
|Central Everglades Planning Project||Planning||Yes||Design tests, project phasing, post-construction contingency options, and operations linked to monitoring|
a Indicates that the project had some components of adaptive management even though it did not have a formal adaptive management plan.
NOTE: Projects are listed chronologically by when they were authorized for construction or when the planning chief’s report was approved for Congress.
SOURCE: Modified from LoSchiavo et al. (2013).
guides are the products of years of effort to develop a coherent, generalized, and comprehensive structure for adaptive management planning for CERP projects in response to repeated recommendations and mandates, and as such they represent significant progress toward adaptive management planning.
Recommendations to develop decision analysis tools to support the adaptive management process have been a focus of two previous NRC reports (NRC, 2010, 2012a). Formal decision frameworks to integrate scientific information from monitoring activities, stakeholder values, and costs, while addressing risk and uncertainty, are crucial to providing transparent decision support to weigh multiple objectives in highly complex and uncertain multiagent systems such as the CERP. The development of multicriteria decision analysis tools to supplement adaptive management for the CERP was under way during the prior committee’s review (NRC, 2012a). The year 2012 marked the Phase 1 completion of a Bayesian network decision analysis tool intended to “provide managers with a framework for evaluating and assessing multiple restoration objectives (performance measures, constraints, costs, risk/uncertainty, and social values) in order to understand how implementation of a program and/or project and its adaptive management plan(s) should change based on a given state of information” (Convertino et al., 2012, 2013). In a proof-of-concept case study, the tool was applied to management alternatives related to the decompartmentalization of WCA-3. The decision support tool characterizes linkages between the project objectives, conceptual and predictive models, the direct and indirect effects of project alternatives on project objectives, stakeholder values to weight objectives, and the uncertainty associated with achieving competing objectives. A distinctive feature of this tool is a global sensitivity analysis that allows for assessment of the value of information each parameter in the decision tool contributes to the decision. In this way the decision support tool can inform the monitoring activities that can optimally reduce uncertainties while minimizing costs induced in redirecting or increasing data acquisition efforts in the context of meeting restoration objectives. If funding for the project is continued, this tool will be improved in Phase 2 by broadening the stakeholder involvement and including greater depth and breadth in spatial and ecological parameters and expanded in Phase 3 to the larger ecosystem under the CERP (Convertino et al., 2012).
2014 SYSTEM STATUS REPORT
RECOVER System Status Reports (SSRs) provide periodic assessments of monitoring data throughout the South Florida ecosystem to support adaptive management and improve CERP planning and implementation. The 2014 Draft SSR (RECOVER, 2014a), the fifth in the series, was released in late March
2014, and represents a synthesis of 5 years of monitoring data and scientific research since the last comprehensive SSR was released in 2009. The document is “intended to convey key scientific information to water managers, budget directors, decision-makers, and the public about the status of the Everglades ecosystem to support restoration and water management decisions” (RECOVER, 2014a).
The 2014 Draft SSR, like its predecessors, is a comprehensive document. The committee’s review addresses the degree to which it provides information to support adaptive management, and because the document became available late in the committee process, the committee focused on Chapters 1 (Key Findings) and 4 (Systemwide Science). In brief, the committee concludes that the SSR is well written and provides good information, including syntheses and recommendations, that are helpful to management decisions about Everglades restoration. Some specific comments are provided as examples below.
The Key Findings (Chapter 1) of the 2014 Draft SSR set the stage by reporting recent hydrologic and climate conditions affecting the region between 2009 and 2013, compared with historical averages. Overall, it provides a succinct summary of major findings with regard to status and trends, projects and operations, and new science covering scales from project level to systemwide. A strength of the document is its synthesis of a huge array of monitoring data and recent research into science-based recommendations for management. Rather than simply reporting observed trends, the 2014 Draft SSR explains and documents the causal mechanisms and provides recommendations for continued ecological improvements. For example, on the basis of new research findings on oyster survival in the St. Lucie Estuary, the SSR documents the adverse effects of back-to-back dry years and proposes salinity targets that could be used in the operational plans for the Indian River Lagoon-South project. Research also determined that oyster restoration in the St. Lucie Estuary is limited by suitable substrate rather than the supply of larvae, and the SSR recommends substrate enhancement just prior to spawning to improve restoration outcomes. Similar synthesis of findings and recommendations are provided for the Greater Everglades, Lake Okeechobee, and Florida Bay.
The 2014 Draft SSR also documents ecosystem improvements that can be quantitatively linked to CERP and non-CERP projects:
• Hydrology improved due to the operational part of the Deering Estate Biscayne Bay Coastal Wetlands expedited project;
• Picayune Strand showed higher water levels near the filled Prairie Canal (1 to 2 feet higher) and vegetation is starting to show signs of improvement and moving closer to reference conditions;
• Hydroperiods were 50 days longer (on an annual average basis) along the centraleastern edge of Everglades National Park as a result of the C-111 South Dade project; and
• Roseate spoonbill nesting improved, most likely due to favorable climatic conditions and better real-time environmental coordination with water management operational decisions.
The SSR does not overstate the ecological project responses (citing these as “demonstrations of small restoration successes”) and points to steps necessary to increase observable improvements in the Biscayne Bay Coastal Wetlands and Picayne Strand projects. The document also highlights the continuing ecosystem declines and “the need for and value of authorizing, constructing, and operating more CERP restoration projects to achieve systemwide hydrologic (water quantity, quality, timing, and distribution) and ecological (flora, fauna, and landscape) goals and objectives.”
In Chapter 4, Systemwide Science, the draft SSR reflects a subject-matter focus that is quite similar to the focus of this NRC report, with extensive information and discussion of climate change and invasive species, including a substantial appendix devoted to invasive species. The draft SSR includes discussions of the implications for restoration of changing climate and rising sea level, and its discussions and analyses of invasive species include regional and systemwide status and trends. The 2014 SSR also provides a comprehensive review of recent research and data on the role of fire in the Everglades (described as “one of the first attempts to reconcile the historical data set of fire history in ENP [Everglades National Park] and BCNP [Big Cypress National Preserve] with the current management”) and the implications for fire management. These summaries represent important and useful synthesis efforts, building on other recent science synthesis reports (RECOVER, 2011b; SERES Project Team, 2010; WG and SCG, 2010) summarized in NRC (2012a).
The committee concludes that the Draft 2014 SSR reflects a comprehensive, scientifically up-to-date and sound approach and execution. It is well organized and illustrated, and for such a large document, it is easy to read. The document is very clear and explicit in connecting the information presented with the needs of managers as they make restoration decisions concerning project design, construction, implementation, and operation. One area that could receive additional attention is at the intersection between water quality and hydrology, including recognition where conflicts exist between near-term restoration goals.
REVIEW OF THE SCIENCE PLAN FOR EVERGLADES STORMWATER TREATMENT AREAS
The SFWMD in collaboration with the U.S. Environmental Protection Agency and the Florida Department of Environmental Protection developed the Science Plan for the Everglades Stormwater Treatment Areas (STAs; SFWMD, 2013d) to investigate critical factors that regulate the sustainable removal of phosphorus by STAs. The science plan is intended to support a $50 million water quality research program over the next 10 years. The science plan identified several key questions (Box 7-1) that need to be addressed to improve the understanding of various physical, chemical, and biological factors regulating the total phosphorus concentration in STA outflows and research and monitoring efforts to address them. Examples of proposed research include studies on the effects of inflow phosphorus concentrations and loads, uptake of phosphorus by vegetation, microbial activity in soils and the water column, and the stability of accreted phosphorus in soil compartments. The SFWMD plans to use the results of these investigations to improve the design and operations of STAs to achieve compliance with the total phosphorus water quality-based effluent limit (WQBEL).4 Thus, the primary objective of this Science Plan is to improve understanding of the external and internal drivers that regulate the performance of STAs at low phosphorus concentration.
Overall, the Science Plan is comprehensive and well developed to meet general operational goals of the STAs. Additional comments and suggestions regarding the six key research questions are provided in Box 7-1. There are also many interesting and useful science subquestions identified, but their usefulness in developing improved STA management strategies needs additional consideration. One overarching concern is the single-minded focus on phosphorus cycling in the Science Plan, to the detriment of important analyses of the role of other macroelements (carbon, nitrogen, and sulfur) on the regulation of total phosphorus in STA outflows. It is critical to recognize the importance of coupled biogeochemical cycles of these macroelements in regulating sustained performance of STAs. Additionally, the Science Plan does not include any discussion on the influence of extreme events such as hurricanes and severe droughts. Currently, 60 percent of the STA treatment is in submerged aquatic vegetation, which has been shown to be more prone to disturbances from extreme events.
4 The WQBEL is a numeric discharge limit used to regulate permitted discharges from the STAs so as not to exceed a long-term geometric mean of 10 μg/L within the Everglades Protection Area. This numeric value is now translated into a flow-weighted mean (FWM) total phosphorus (TP) concentration and applied to each STA discharge points, which now must meet the following: (1) the STAs are in compliance with WQBEL when the TP concentration of STA discharge point does not exceed an annual FWM of 13 μg/L in more than three out of five years, and (2) annual FWM of 19 μg/L in any water year (Leeds, 2014).
Reflections on Key Questions from the Science Plan for the Everglades Stormwater Treatment Areas
Key Question 1: How can the flow equalization basins (FEBs) be designed and operated to moderate and optimize phosphorus concentrations, phosphorus loading rates, and hydraulic loading rates entering the STAs, possibly in combination with water treatment technologies, and/or inflow canal dredging/lining?
The Restoration Strategies program relies heavily on FEBs to improve the operation of STAs. Depending on water depth and residence time, FEBs can function both as sources and sinks for nutrients, especially phosphorus. The FEBs may also respond differently to low flows and high flows. The proposed research and monitoring plan will provide new data that will be useful for implementing appropriate adaptive management plans to support the design and operation of FEBs for maximum effectiveness. Properly managed FEBs will potentially reduce inflow total phosphorus concentrations, thus reducing loads to STAs.
Key Question 2: How can internal loading of phosphorus to the water column be reduced or controlled, especially in the lower reaches of the treatment trains?
Microbial, periphyton, and vegetation communities are the major ecosystem biotic components that respond to and exert reciprocal control on abiotic drivers and in doing so generate biogeochemical cycles that may influence STA outflow total phosphorus (TP) concentrations. For effective management of STAs, it is critical to understand the internal biogeochemical dynamics of biotic and abiotic transformations in water, soils, and periphyton that regulate low TP levels as proposed in the Science Plan.
For the past two decades, state and federal agencies and universities have accumulated a wealth of data on internal dynamics of microorganisms, periphyton, and vegetation (SAV and EAV) in the Everglades Protection Area (WCAs and Everglades National Park) and their role in regulating low TP concentrations (10 μg TP/L) in surface waters (see Reddy et al., 2011, for a compilation of review papers). Although STAs are operated at much higher flow rates and TP loading rates than the rates encountered in the Everglades, contrasting these two ecosystems (STAs and the Everglades Protection Area) can provide insights to develop strategies to manage STA outflows for low TP concentrations.
Key Question 3: What measures can be taken to enhance vegetation-based treatment in STAs and FEBs?
The role of biotic communities in assimilating phosphorus from the soil and water column is well known. In addition to assimilating phosphorus into their tissues, these
CONCLUSIONS AND RECOMMENDATIONS
Useful long-term systemwide monitoring requires stable funding. If funding cuts result in significant gaps in critical long-term monitoring data, important changes and patterns could be missed, and data collected before or after the
biotic communities will also alter the micro- and macroenvironment in the water column and soils and influence phosphorus retention and release. Several studies are proposed in the Science Plan to understand the role of vegetation to reduce phosphorus concentration of the water column, with primary focus on phosphorus assimilation and storage in the vegetation. However, additional attention to nutrient balance (macro- and micro-nutrients) and abiotic and biotic reactions that may be more important in regulating phosphorus retention is merited.
Key Question 4: How can the biogeochemical and/or physical mechanisms be managed to further reduce soluble reactive, particulate and dissolved organic phosphorus concentrations at the outflow?
Very little is known on transformations of particulate phosphorus (PP) and dissolved organic phosphorus (DOP) within various treatment cells. The challenge for STA optimization is to develop innovative management strategies to reduce internal production of PP and DOP. The Science Plan identifies various technologies to reduce PP and DOP, and some of these technologies are currently being tested. Although this practical approach is important and useful, it is equally important to conduct some studies that will determine the role of physical, chemical, and biological processes, vegetation types, and hydraulic loading rates on internal production of PP and DOP. This information will provide support to determine the type of technologies needed reduce outflow PP and DOP.
Key Question 5: What operational and/or design refinements could be implemented at existing STAs and future features (i.e., STA expansions, flow equalization basins) to improve and sustain treatment performance?
The Science Plan identifies the importance of some operational and/or design refinements to STA to improve treatment performance. Examples of some operational/design refinements may include: managing high flows and low flows by taking advantage of FEBs and altering hydraulic retention times in treatment cells; sediment management in inflows and outflows; minimizing short-circuiting and improving flow distribution; inducing downward flow in STAs to reduce upward flux of phosphorus. These strategies may provide some operational flexibility to improve the overall performance of STAs to reduce TP levels in outflow.
Key Question 6: What is the influence of wildlife and fisheries on the reduction of phosphorus in the STAs?
Wildlife (birds, fish, alligators, macro-crustaceans, mollusks, and others) can be a significant factor in phosphorus loading to STAs, especially in treatment cells near outflows. It is important to determine direct and indirect effects of wildlife of the extent of phosphorus loading and its ultimate impact on outflow TP concentrations.
funding gaps could lose their value. Given the substantial financial investment in Everglades restoration by both the state and the federal governments, a dedicated source of funding could provide ongoing long-term systemwide monitoring and assessment that is critical to meeting restoration objectives, ensuring that public resources are spent wisely, and adaptively managing restoration efforts.
A comprehensive reevaluation of restoration-related monitoring is needed to determine its adequacy considering budget pressures, the extended CERP implementation time frames, and the potential impacts of climate change and sea-level rise. The dramatic 2011 cuts to MAP funding create a risk that adequate long-term data will not be available to assess the effects of restoration projects in a systemwide context once they are implemented. This reevalution should clearly articulate the value of the highest priority monitoring to future restoration decision making and the risks of ceasing such monitoring. Also, CERP planners should identify opportunities for improving the efficiency of current monitoring and reducing the frequency of some monitoring in the context of the current slow pace of CERP implementation.
Renewed attention to science coordination is warranted. Scientific research and monitoring programs require coordination and communication to be effective and efficient, but science leadership and coordination appear to have waned over the past few years. For the SCG to significantly contribute to better science coordination, the SCG would need to have adequate funding and staff and a clear charge to address critical science needs from a restoration-wide perspective.
In recent years, project-level adaptive management plans have become more sophisticated and better integrated with project planning as guidance has been developed and refined. After calls for adaptive management since 2000, significant progress has been made toward adaptive management planning at multiple scales. The Central Everglades Planning Project adaptive management plan is the most complex and sophisticated to date.
The 2014 System Status Report is an effective synthesis of recent monitoring and research and provides valuable science-based guidance to restoration decision makers. Its key findings summarize ecosystem status and trends, monitoring related to implemented CERP and non-CERP projects, and new science relevant at local and systemwide scales. A particular strength of the document is its explanations of ecosystem trends and their causal mechanisms that lead to recommendations for possible changes in project design or operations to improve restoration outcomes.
Implementation of the Restoration Strategies Science Plan to develop strategies to meet STA discharge criteria is a high priority for Everglades restoration. The Science Plan and associated $50 million research program is an important contribution that should improve STA management and effectiveness. However, the single-minded focus on phosphorus in the Science Plan may overlook the influence of other macroelements such as carbon, nitrogen, and sulfur on sustained STA performance.