2
The Restoration Plan in Context

In this chapter, the stage is set for the committee’s third biennial assessment of restoration progress in the South Florida ecosystem. Background is provided on the ecosystem decline, restoration goals, the needs of a restored ecosystem, and the specific activities of the restoration project. Important changes in the context for restoration, now 10 years after the Comprehensive Everglades Restoration Plan (CERP) was launched, are discussed with a specific focus on endangered species trends, water quality, and the human system. The watershed context is also discussed in considerable detail, because the system cannot be understood without that context. Canals, levees, and other water management structures have profoundly altered the hydrology, geomorphology, and connectivity of the system, and restoration of the ecosystem will require consideration of the ecosystem services (e.g., natural water storage, water quality treatment) once provided throughout the entire watershed.

THE SOUTH FLORIDA ECOSYSTEM’S ENVIRONMENTAL DECLINE

The Everglades once encompassed about 3 million acres of slow-moving water and associated biota that stretched from Lake Okeechobee in the north to Florida Bay in the south (Figures 1-1a and 2-1a). The nature of the water flow has characteristics that provide the functional basis of the Everglades, and as the flows have changed (Figure 2-1), the physical, chemical, and biological components of the Everglades ecosystems also have changed. In the following section the changes in the hydrologic and geomorphologic characteristics of water flows are explored in the watersheds of Central and South Florida.

Changes to the Kissimmee-Lake Okeechobee-Everglades Watershed

From the hydrologic perspective, the map of Central and South Florida is dominated by the 9,000 square mile Kissimmee-Okeechobee-Everglades water-



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2 The Restoration Plan in Context In this chapter, the stage is set for the committee’s third biennial assessment of restoration progress in the South Florida ecosystem. Background is provided on the ecosystem decline, restoration goals, the needs of a restored ecosys- tem, and the specific activities of the restoration project. Important changes in the context for restoration, now 10 years after the Comprehensive Everglades Restoration Plan (CERP) was launched, are discussed with a specific focus on endangered species trends, water quality, and the human system. The watershed context is also discussed in considerable detail, because the system cannot be understood without that context. Canals, levees, and other water management structures have profoundly altered the hydrology, geomorphology, and connec- tivity of the system, and restoration of the ecosystem will require consideration of the ecosystem services (e.g., natural water storage, water quality treatment) once provided throughout the entire watershed. THE SOUTH FLORIDA ECOSYSTEM’S ENVIRONMENTAL DECLINE The Everglades once encompassed about 3 million acres of slow-moving water and associated biota that stretched from Lake Okeechobee in the north to Florida Bay in the south (Figures 1-1a and 2-1a). The nature of the water flow has characteristics that provide the functional basis of the Everglades, and as the flows have changed (Figure 2-1), the physical, chemical, and biological components of the Everglades ecosystems also have changed. In the following section the changes in the hydrologic and geomorphologic characteristics of water flows are explored in the watersheds of Central and South Florida. Changes to the Kissimmee-Lake Okeechobee-Everglades Watershed From the hydrologic perspective, the map of Central and South Florida is dominated by the 9,000 square mile Kissimmee-Okeechobee-Everglades water- 23

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24 Progress Toward Restoring the Everglades FIGURE 2-1 Water flow in the Everglades under (a) historical conditions, (b) current conditions, and (c) conditions envisioned upon completion of the Comprehensive Everglades Restoration Plan (CERP). Figure 2-1.eps SOURCE: Graphics provided by USACE, Jacksonville District. bitmap shed (Figure 2-2), a connected drainage basin that extends from the Orlando area 250 miles southward to Florida Bay (McPherson and Halley, 1996). The water- shed includes three primary sub-basins: the Kissimmee River, Lake Okeechobee and its tributaries, and the Everglades. Prior to economic development and the creation of artificial drainage systems, water flowed from a series of small lakes at the northern end of this system through the Kissimmee River into Lake Okeechobee. During rainy periods, the lake spilled water southward over its low perimeter and into the Everglades, moving as a broad shallow sheet of water until it became more concentrated and flowed to tidewater through Shark River, Taylor, and Loxahatchee sloughs as well as through coastal rivers. Rainfall onto the 4,500 square mile Everglades augmented this overland flow and sustained it during dry periods. The conversion of the uninhabited Everglades wilderness into an area of high agricultural productivity and cities was a dream of 19th-century investors, and, beginning in the early 1880s, water-control projects were built to drain the wetlands. By the end of the 20th century, the extensive water-control system to supply water to agricultural and urban areas and to provide flood protection to

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The Restoration Plan in Context 25 FIGURE 2-2 Pre-drainage water flows in the Kissimmee-Lake Okeechobee-Everglades Figure 2-2.eps watershed. bitmap SOURCE: McPherson and Halley (1996).

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26 Progress Toward Restoring the Everglades developed areas included more than 2,600 miles of canals and levees, 64 major pumping stations, and about 1,300 control structures.1 These installations, along with highway construction and urbanization, have dismembered the original flow paths of the Kissimmee-Lake Okeechobee-Everglades watershed (Figure 2-1). Changes in the Kissimmee River Sub-Basin Before the advent of drainage, canal, and levee projects that accompanied economic development, the far northern portion of the Kissimmee-Okeechobee- Everglades drainage basin was characterized by poorly connected lakes near the present location of Orlando. The Kissimmee River flowed southward from this lake district and emptied into Lake Okeechobee. In this pre-drainage period, the river was a highly sinuous, single-thread channel 90 miles long, with a flood plain 2 or more miles wide, and flanked by generally flat landscapes (McPher- son and Halley, 1996). Under these geomorphic and hydrologic conditions, seasonal high flows and occasional large floods caused the river to overflow its banks, and periodically produced new channel locations. During these over- bank flow events, the flood plains stored considerable amounts of water, and they were directly connected in a hydrologic sense to the channel. Eventually, flows from the Kissimmee River Basin passed downstream into Lake Okeechobee and thence to the Everglades, so that even though the river was distant from the Everglades, it was an integral part of Everglades hydrology. Early drainage projects begun between 1881 and 1894 affected the flow of water in the watershed north of Lake Okeechobee. By the late 1800s, more than 50,000 acres north and west of Lake Okeechobee had been drained and cleared for agriculture (Grunwald, 2006). As a flood control measure, the U.S. Army Corps of Engineers (USACE) began construction of the Kissimmee River Canal (C-38 Canal) in 1961, completing it 10 years later. What was once a 90-mile-long winding river was converted into a 52-mile-long, channelized conduit with a more direct route to Lake Okeechobee. The canal also included six locks and dams, a structural arrangement that introduced considerable hydrologic adjustments to the system. Over-bank flooding became very rare, and 40,000 to 50,000 acres of the flood plain were converted from wetlands to terrestrial habitats that became agricultural lands and pastures (McPherson and Halley, 1996). These projects affected water quantity and water quality in Kissimmee River discharges. The loss of flood-plain space meant that the basin stored less water internally during high flows, the groundwater recharge was less, and the annual See http://www.sfwmd.gov/portal/page/portal/sfwmdmain/managing%20%20protecting%20 1 water.

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The Restoration Plan in Context 27 total water yield of the river to Lake Okeechobee probably increased by about 20 percent or more (based on USACE and SFWMD, 1999). Because the naturally winding course of the river along with its associated oxbow lakes and wetlands were disconnected from the active river regime of the Kissimmee, their nutrient- filtering capabilities were lost. The loss of these filters and the increased nutrient loading that resulted from agricultural activities resulted in elevated deliveries of nutrients to Lake Okeechobee (Federico, 1982). Changes in the Lake Okeechobee Sub-Basin Prior to drainage and development, Lake Okeechobee was a primary con- nector and regulator in the Kissimmee-Okeechobee-Everglades hydrologic sys- tem (Steinman et al., 2002). The lake, bounded by low rises on all sides, prob- ably had an average depth of about 20 feet during wet periods and extended to a surface area of more than 730 square miles (McPherson and Halley, 1996). The lake expanded laterally during rainy periods (sometimes as much as several miles) across gently sloping margins, particularly in the northwestern sector of the lake’s edge. During dry periods the lake shrank into its basin, abandoning the low-gradient, marshy areas on its northwest perimeter; its general depth probably declined to about 16 feet. When the lake inflows exceeded its capac- ity, water overflowed the perimeter of the lake westward into marshlands of the Caloosahatchee River Basin and southward to the Everglades (see also Chapter 4 for a discussion of pre-drainage water budgets) (USACE and SFWMD, 1999). In the late 1800s and early 1900s agricultural development slowly expanded farming areas around Lake Okeechobee and on lands south of the water body. Farmers found that during drought periods the lack of water crippled production, and in wet years floods were a major hazard. In response to major floods in 1903, the state created four canals to conduct excess water from Lake Okeechobee to the Atlantic Ocean, allowing managers to control water levels in the lake. The local drainage district constructed a sand and muck levee along 47 miles of the lake’s perimeter. Devastating hurricanes in 1926 and 1928 stimulated construction of an additional canal (C-44) eastward to connect the lake to the St. Lucie Basin and enlargement of the connection (C-43) between the lake and the Caloosahatchee River to carry more lake water westward to the Gulf of Mexico. Today, large amounts of water are diverted from the original south- ward flow into the estuaries, altering salinity and nutrient loadings. During the 1930s the USACE raised the levee along the lake margin, cutting off the gently sloping terrain that once had been an overflow area. In the 1960s the USACE increased the height of the levee (now known as the Herbert Hoover Dike) to 30 feet. The total effect of the engineering works associated with Lake Okeechobee has been the fundamental alteration of the role of the lake in the Kissimmee-

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28 Progress Toward Restoring the Everglades Okeechobee-Everglades watershed (Lodge, 2005). The quantitative impacts of these changes are discussed in more detail in Chapter 4 (see also Figures 4-1 and 4-2). Understanding the flow of water in the Lake Okeechobee sub-basin is essential to understanding the movement and storage of nutrients in the sub- basin and the tremendous water quality challenges in Lake Okeechobee, as explored more fully in Chapter 5 and in NRC (2008). Changes in the Everglades Sub-Basin Prior to drainage and development projects, the Everglades portion of the Kissimmee-Okeechobee-Everglades drainage basin was a broadly defined zone of flowing water starting at Lake Okeechobee and ending in Florida Bay, bounded on the west by higher terrain in the Big Cypress Swamp and on the east by the sandy rises of the Atlantic Ridge (McPherson and Halley, 1996). The topographic gradient through the Everglades is only about 2 inches per mile, so that the flow of water was only 100 feet per day. The form of the flow was in broad sheets a few inches to a few feet deep. In 1848 Buckingham Smith (quoted in Fling et al., 2009) observed: “The water is pure and limpid and almost imperceptibly moves, not in partial currents, but, as it seems, in a mass, silently and slowly to the southward.” Well-defined sloughs, where water flowed during all but the driest years, provided important habitat and foraging sites for wading birds. The “river of grass” shaped the characteristic features of the landscape in a delicate balance between form and process. Field maps of the elongated tree islands that rise above the sawgrass suggest that the orientation of sloughs, ridges, and tree islands are all connected to the dominant flow direction (Parker et al., 1955; Sklar and van der Valk, 2002). The construction of canals, levees, and dikes beginning in the early 20th century partitioned the Everglades portion of the Kissimmee-Okeechobee- Everglades watershed into discrete, poorly integrated units (Figure 2-1b). In 1907 Governor Napoleon Bonaparte Broward created the Everglades Drainage District to construct a vast array of ditches, canals, dikes, and “improved” channels. By the 1930s, 440 miles of other canals altered the hydrology of the Everglades (Blake, 1980). After extensive flooding in 1947 and increasing demands for improved agricultural production and flood control for the expanding popula- tion centers on the southeast Florida coast, the U.S. Congress authorized the Central and South Florida (C&SF) Project, an extensive, extremely sophisticated water management system. The C&SF Project provided flood control with the construction of a levee along the eastern boundary of the Everglades to prevent flows into the southeastern urban areas, established the 700,000 acre Everglades Agricultural Area (EAA) south of Lake Okeechobee (see Box 2-1), and created a series of water conservation areas (WCAs) to regulate water levels in devel-

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The Restoration Plan in Context 29 BOX 2-1 The Everglades Agricultural Area Making the land in the Everglades Agricultural Area (EAA) (see Figure 1-3) suitable for agriculture was one of the original primary objectives of the Central and South Flor- ida (C&SF) Project (Lodge, 2005). Preliminary assessments in the late 1940s identified the peat soils just south of the southern rim of Lake Okeechobee as ideal for agriculture (Jones, 1948). Between 1950 and 1973, the USACE constructed a major dike on the east side of the agricultural area, established water delivery and drainage canals, and added pumps and control gates to manage water for agriculture. It also created the water conservation areas (WCAs) as temporary holding ponds that could accept surplus water during wet periods and provide additional water for agriculture during dry periods. Lake Okeechobee could also be managed to supply water in dry periods and accept excess water in wet periods. All of the EAA was designed for agricultural production, except for two fairly small wildlife management areas (WMAs): Rotenberger WMA and Holey Land WMA (Lodge, 2005). When the EAA was complete in the early 1970s, it subsumed 27 percent of the pre-drainage Everglades. In comparison, the WCAs oc- cupy 37 percent, and Everglades National Park covers about 20 percent (Lodge, 2005; Secretary of Interior, 1994). As of the mid-2000s, the overwhelmingly dominant land use in the EAA is sugar production, with less than 1 percent used for pasture (R. Budell, Florida Agriculture and Consumer Services, personal communication, 2010). oped areas in the remaining space between the lake and Everglades National Park (Light and Dineen, 1994). By protecting urban and agricultural lands in South Florida from floods and droughts (see Box 2-2), the project facilitated the prosperous economic development in the region, but it dramatically altered the Everglades ecosystem. Ecological Implications of Watershed Changes The profound hydrologic alterations were accompanied by many changes in the biotic communities in the ecosystem, including reductions and changes in the composition, distribution, and abundance of the populations of wad- ing birds, the most visible component of the Everglades biota and symbolic to many stakeholders of the status of the entire ecosystem. Urban and agricultural development have reduced the Everglades to about one-half its pre-drainage size (Davis and Ogden, 1994; Figure 1-1b) and have contaminated its waters with phosphorus, nitrogen, sulfate, mercury, and pesticides. Today, the federal government has listed 67 plant and animal species in South Florida as threatened or endangered, with many more included on state lists. Some distinctive Ever- glades habitats, such as custard-apple forests and peripheral wet prairie, have

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30 Progress Toward Restoring the Everglades BOX 2-2 Climate Conditions in South Florida Water management for both human and natural systems occurs within a context of high variation and frequent extremes in climate conditions. South Florida has a humid subtropical to tropical climate, and high annual precipitation (47 to 62 inches on average for Everglades weather stations). Rainfall occurs on 70 to 80 days per year, but often with high intensity. About 60-65 percent of the rainfall occurs during the summer wet season and is associated with thunderstorms. The central portion of the state experi- ences about 85 thunderstorms per year. Another notable feature of the precipitation regime in Florida is the frequency of torrential rain (over 3 inches within 24 hours). Pre- cipitation variability between years is also very high; total rainfall amounts have ranged from 34 to 88 inches, with ranges of less than 40 to approximately 80 inches within most decades since 1890. Another characteristic of South Florida’s climate is the frequency of tropical storms and hurricanes. In most years, at least one tropical storm or hurricane affects the region, with the maximum on record being 21 such storms in one year (1933). Although the total amounts of rainfall inputs are large, the high temperature regime results in high evapotranspiration, so that possibility of drought is always present. Droughts generally follow low precipitation inputs during the wet season, but, as with other components of the South Florida climate system, there is great variability in the location, frequency, and duration of droughts. These characteristics imply that the high variability in precipitation inputs coupled with constant high evaporative demand result in both frequent excesses of water that must be managed to prevent urban and agricultural flooding and also deficits of water that require drought management, with a high potential for years of high precipitation to alternate with drought stresses (Duever et al., 1994). See also http://www.ncdc.noaa.gov/oa/ncdc.html for additional information on the climate of Florida. disappeared altogether, while other habitats are severely reduced in area (Davis and Ogden, 1994; Marshall et al., 2004). Mercury contamination led the state of Florida to restrict consumption of nine species of fish in roughly 2 million acres of the Everglades (Scheidt and Kalla, 2007). Phosphorus from agricultural runoff has impaired water quality in large portions of the Everglades and has been particularly problematic in Lake Okeechobee (Flaig and Reddy, 1995). The Caloosahatchee and St. Lucie estuaries, including parts of the Indian River Lagoon, have been greatly altered by high and extremely variable freshwater discharges that bring nitrogen, phosphorus, and contaminants into the estuaries and alter the salinities that control the abundance of estuarine organisms (Doer- ing, 1996; Doering and Chamberlain, 1999). At least as early as the 1920s, private citizens were calling attention to the degradation of the Florida Everglades (Blake, 1980). However, by the time Marjory Stoneman Douglas’s classic book The Everglades: River of Grass was published in 1947 (the same year that Everglades National Park was dedicated),

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The Restoration Plan in Context 31 the South Florida ecosystem had already been altered extensively. Prompted by concerns about deteriorating conditions in Everglades National Park and other parts of the South Florida ecosystem, the public, as well as the federal and state governments, directed increasing attention to the adverse ecological effects of the flood-control and irrigation projects beginning in the 1970s (Kiker et al., 2001; Perry, 2004). By the late 1980s it was clear that various minor corrective measures undertaken to remedy the situation were insufficient. As a result, a powerful political consensus developed among federal agencies, state agencies and commissions, Native American tribes, county governments, and conserva- tion organizations that a large restoration effort was needed in the Everglades (Kiker et al., 2001). This recognition culminated in the CERP, which builds on other ongoing restoration activities of the state and federal governments to create one of the most ambitious and extensive restoration efforts in the nation’s history (see Appendix B for a timeline of significant events in South Florida ecosystem management). SOUTH FLORIDA ECOSYSTEM RESTORATION GOALS Several goals have been articulated for the restoration of the South Florida ecosystem, reflecting the various restoration programs. The South Florida Ecosys- tem Restoration Task Force (Task Force), an intergovernmental body established to facilitate coordination in the restoration effort, has three broad strategic goals: (1) “get the water right,” (2) “restore, preserve, and protect natural habitats and species,” and (3) “foster compatibility of the built and natural systems” (SFERTF, 2000). These goals encompass, but are not limited to, the CERP. The Task Force works to coordinate and build consensus among the many non-CERP restoration initiatives that support these broad goals. The goal of the CERP, as stated in the Water Resources Development Act of 2000 (WRDA 2000), is “restoration, preservation, and protection of the South Florida Ecosystem while providing for other water-related needs of the region, including water supply and flood protection.” The Programmatic Regulations (33 CFR 385.3) that guide implementation of the CERP further clarify this goal by defining restoration as “the recovery and protection of the South Florida eco- system so that it once again achieves and sustains the essential hydrological and biologic characteristics that defined the undisturbed South Florida ecosystem.” These defining characteristics include a large-areal extent of interconnected wetlands, extremely low concentrations of nutrients in freshwater wetlands, sheet flow, healthy and productive estuaries, resilient plant communities, and an abundance of native wetland animals (DOI and USACE, 2005). Although devel- opment has permanently reduced the areal extent of the Everglades ecosystem, the CERP hopes to recover many of the Everglades’ original characteristics and

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32 Progress Toward Restoring the Everglades natural ecosystem processes. At the same time, the CERP is charged to maintain current levels of flood protection (as of 2000) and provide for other water-related needs, including water supply, for a rapidly growing human population in South Florida (DOI and USACE, 2005). Although the CERP contributes to each of the Task Force’s three goals, it focuses primarily on restoring the hydrologic features of the undeveloped wetlands remaining in the South Florida ecosystem, on the assumption that improvements in ecological conditions will follow. Originally, “getting the water right” had four components—quality, quantity, timing, and distribution. How- ever, the hydrologic properties of flow, encompassing the concepts of direction, velocity, and discharge, have been recognized as an important component of getting the water right that had previously been overlooked (NRC, 2003c; SCT, 2003). Understanding of the CERP hydrologic goals is derived from paleoecol- ogy research (e.g., Willard et al., 2001; Saunders et al., 2006; Bernhardt and Willard, 2009) and hydrologic models that simulate the pre-drainage hydrol- ogy, such as the Natural System Model (NSM; see Chapter 4 and Box 4-1). The water quality goals are outlined by the existing legal and regulatory framework (described in more detail in Chapter 5). Numerous studies have supported the general approach of hydrologic restoration to achieve ecological restoration (Davis and Ogden, 1994; NRC, 2005; SSG, 1993), although it is widely rec- ognized that recovery of the native habitats and species in South Florida may require restoration efforts, such as controlling exotic species and reversing the decline in the spatial extent and compartmentalization of the natural landscape (SFERTF, 2000; SSG, 1993). The goal of ecosystem restoration can seldom be the exact re-creation of some historical or preexisting state because physical conditions, driving forces, and boundary conditions usually have changed and are not fully recoverable. Rather, restoration occurs along a continuum from intensive deconstruction and ecosystem reconstruction efforts in heavily impacted areas to improving conditions in less modified ones (Hobbs and Norton, 1996). Implicit in the understanding of ecosystem restoration is the recognition that natural systems are self-designing and dynamic and, therefore, it is not possible to know in advance exactly what can or will be achieved. Thus, ecosystem restoration is an enterprise with some scientific uncertainty in methods or outcomes that requires continual testing of goals and assumptions and monitoring of progress (NRC, 2007). Moreover, large-scale restoration inevitably involves economic and ecological tradeoffs depending on which sites in the landscape and which attributes of the ecosystem are emphasized (e.g., remediation to reduce levels of hazardous substances, productivity, recovery of rare species). The issue of tradeoffs is a theme that runs through much of Chapters 4 and 5 of this report.

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The Restoration Plan in Context 33 What Natural System Restoration Requires Restoring the South Florida ecosystem to a desired ecological landscape requires reestablishment of the critical processes that sustained its historical functions. Although getting the water right is the oft-stated and immediate goal, the restoration will be recognized as successful if it restores the distinc- tive characteristics of the historical ecosystem to the remnant Everglades (DOI and USACE, 2005). Getting the water right is a means to an end, not the end in itself. The hydrologic and ecological characteristics of the historical Everglades serve as restoration goals for a functional (albeit reduced in size) Ever- glades ecosystem. The first Committee on Independent Scientific Review of Ever- glades Restoration Progress (CISRERP) review identified five critical components of Everglades restoration: 1. Enough water storage capacity combined with operations that allow for appropriate volumes of water to support healthy estuaries and the return of sheet flow through the Everglades ecosystem while meeting other demands for water; 2. Mechanisms for delivering and distributing the water to the natural system in a way that resembles historical flow patterns, affecting volume, depth, veloc- ity, direction, distribution, and timing of flows; 3. Barriers to eastward seepage of water so that higher water levels can be maintained in parts of the Everglades ecosystem without compromising the cur- rent levels of flood protection of developed areas as required by the CERP; 4. Methods for securing water quality conditions compatible with restora- tion goals for a natural system that was inherently extremely nutrient poor, particularly with respect to phosphorus; and 5. Retention, improvement, and expansion of the full range of habitats by preventing further losses of critical wetland and estuarine habitats and by pro- tecting lands that could usefully be part of the restored ecosystem. If these five critical components of restoration are achieved and the difficult problems associated with other major ecosystem changes, such as invasive spe- cies and altered fire regimes, can be managed, then the basic physical, chemi- cal, and biological processes that created the historical Everglades can once again work to create a functional mosaic of biotic communities that resemble the distinctive characteristics of the historical Everglades. Even if the restored ecosystem does not exactly replicate the historical ecosystem, or reach all of the biological, chemical, and physical targets, the reestablishment of natural processes and dynamics should result in a viable and valuable Everglades eco- system. The central principle of ecosystem management is to provide for the natural processes that historically shaped an ecosystem, because ecosystems are

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The Restoration Plan in Context 51 2008). In 2009, 185 nests were recorded statewide but only 11 were in WCA-3A, producing only two young, which follows the trend of low reproduction from kites in WCA-3A since 2001. Southern WCA-3A had been the most important wetland for kite reproduction since the mid-1960s (Snyder et al., 1989; Cattau et al., 2009). The decline in kite use and nesting success in WCA-3A during the past decade coincides with changes in the regulation schedule in this wetland that were made to improve conditions in Everglades National Park for Cape Sable seaside sparrows (see Chapter 4). In summary, there appear to be conflicting hydrologic habitat requirements for several of the most endangered species in the Everglades that are manifested by the current management of water in WCA-3. Water management changes over the past 10 years have stopped further declines in the sparrow population, but they have not been effective in producing the desired hydrologic conditions to recover this species. Meanwhile, the water management changes have con- tributed to decline of the snail kite reproduction in WCA-3A and to its statewide population crash. Yet, the same set of environmental conditions has resulted in wading bird recovery. These water management challenges are considered in more detail in Chapter 4. Ridge and Slough Landscape Trends The development of a water-control infrastructure for South Florida has resulted in widespread changes in ridge and slough landscapes. These distinc- tive landscapes consist of parallel ridges of peat and intervening water bodies (or sloughs) 100 to 500 feet wide with local relief of only about 1 foot and are broadly oriented along the local direction of water flow. These landscapes origi- nally occupied nearly 4,000 square miles of South Florida, but they now cover only about half of their former extent. The landscapes degrade when canals and levees disrupt sheet flow, resulting in flattening of the landscape, loss of aquatic communities, and disorientation of the features (Figures 2-10 and 2-11). The ridge and slough system is also degraded by increased frequency of fires in areas with frequent drawdowns. In an early evaluation, the Science Coordination Team (SCT, 2003) concluded that “1) The Everglades ridge and slough landscape has changed and is continuing to change significantly, and 2) the landscape changes are having detrimental ecological effects on Everglades plants and animals.” Recent changes in ridge and slough landscapes show a variety of trends, with increases in coverage of such landscapes in some places, declines in oth- ers, and substantial variability in trends in some places (Figure 2-12; Sklar et al., 2009b). The diagrams in Figure 2-12 represent historical trends in a metric of landscape patterning in three places in WCA-3A. The metric consists of a series of categories ranging from 1 (a landscape that is mostly similar throughout

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52 Progress Toward Restoring the Everglades FIGURE 2-10 Well-preserved ridge and slough landscape in the northern part of WCA-3, with sawgrass ridges appearing as dark Figure 2-10.eps green and lighter colored, water-filled sloughs. bitmap SOURCE: Photo courtesy of C. McVoy, SFWMD. its extent and that shows no directionality in its forms) to 6 (a landscape that has highly differentiated parts with strongly linear features). High values of this metric indicate a landscape that strongly exhibits the general characteristics of ridge and slough landscapes. Data for evaluating the metric are from areal photographic interpretation. Example N5 in Figure 2-12 from the central part of WCA-3A has shown variable trends of change, first becoming more organized, then less organized, and finally more organized again. Example G3 from the southern WCA-3A has a different history, becoming more organized like typical ridge and slough landscapes, and then remaining unchanged for more than 30 years. Example I1 from the northern WCA-3A shows a steady decline in the landscape metric and has become progressively disorganized and less like a ridge and slough landscape. These representative examples show that recent trends in ridge and

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The Restoration Plan in Context 53 FIGURE 2-11 Degraded ridge and slough landscape in the northern portion of WCA-3A, showing sawgrass Figure 2-11.eps areas in dark green, with lighter water-filled basins. The landscape lacks a coherent directional pattern. bitmap SOURCE: Photo courtesy of C. McVoy, SFWMD. slough landscapes are variable according to location and can undergo significant degradation or enhancement on decadal timescales (Sklar et al., 2009b). As outlined in NRC (2008), there have been drastic declines in the number of tree islands and the area of their coverage in the Everglades generally since the 1940s. The trends in tree island changes are best known for WCA-3A, where repetitive mapping using areal photography has revealed the changes. Specifi- cally, tree island numbers and areal coverage in WCA-3A declined by about two-thirds between 1940 and 1970. Thereafter, the decline to 1995 was more gradual (see also Figure 4-10). Tree island declines in northern WCA-3A have generally been associated with lowered water levels, peat subsidence, and fires, while declines in southern WCA-3A have been more associated with persistent high water levels (see also Chapter 4). Newly released data reveal that between 1995 and 2004 tree island num- bers declined by about 18 percent and tree island areas by about 8 percent

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54 Progress Toward Restoring the Everglades FIGURE 2-12 The historical changes in ridge and slough patterning are displayed for the Figure 2-12.eps years 1940, 1953, 1972, 1984, and 2004 for three study plots (labeled N5, G3, and I1) located bitmap in WCA-3A. The highest value (6) on the y-axis represents strong and linear landscape pat- terns. High values indicate a landscape that strongly exhibits the general characteristics of ridge and slough landscapes. Plot N5 is in central WCA-3B, adjacent to the L-67 levees; G3, lies in the southern portion of WCA-3; and I1 is located in the north central part of WCA-3A, north of Alligator Alley. SOURCE: Sklar et al. (2009b).

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The Restoration Plan in Context 55 (Figure 2-13). The largest areal declines occurred in southern WCA-3A near the L-67 levees followed by northwest WCA-3A. Tree islands in WCA-3B appear to have remained somewhat stable over this time period. The recent data show that the gradual decline of tree islands observed in the prior data has continued through 2004 (F. Sklar, SFWMD, personal communication, 2010). Water Quality Trends The CERP, as laid out in the Yellow Book (USACE and SFWMD, 1999), reflected an expectation that water quality concerns in the South Florida ecosys- tem could be adequately addressed by state efforts launched in the 1990s. Ten years later, water quality has emerged as a serious challenge that remains unre- solved. Despite tremendous efforts by the state of Florida to control phosphorus through best management practices and STAs over the past 15 years (see Chapter 5 for more details), water quality trends show mixed responses. This section highlights data from two areas as examples of water quality trends over the past decade: Lake Okeechobee and the Everglades Protection Area (see Box 1-1). In 2000, Florida enacted the Lake Okeechobee Protection Act (Chapter 00-103, Laws of Florida), which mandated a comprehensive plan to reduce phosphorus loading in the watershed to meet the total maximum daily load (TMDL) of 105 metric tons (mt) per year of surface-water inputs by 2015. Yet, 10 years later, the data show little if any evidence of improvement. Phosphorus loads, representing phosphorus concentration times volumetric discharge rate, fluctuate widely between wet and dry years, but despite implementation of best management practices north of the lake, the loads continue to be well above the goal except in the most severe drought years (Figure 2-14). Additionally, the average inflow phosphorus concentrations have generally remained unchanged (Figure 2-15). Meanwhile, phosphorus concentrations within Lake Okeechobee have risen steadily since the 1970s. A series of hurricanes that suspended phos- phorus-laden sediments in the lake caused a sharp increase starting in 2005, and phosphorus concentrations have not yet returned to pre-hurricane levels (Figure 2-14; McCormick et al., 2010). Water quality trends in the Everglades Protection Area over the last decade are mixed. Flow-weighted mean phosphorus concentrations in inflows to the WCAs have declined substantially from the baseline period 1979-1993 to the four-year period 2005-2009 (Payne et al., 2010b; Figure 2-16). Flow weighting serves to normalize the data to account for natural variations in wet and dry years so that trends become more apparent. The declining trends in the WCAs in Figure 2-16 can be assumed to reflect the role of the best management prac- tices and STAs in dramatically decreasing overall phosphorus loads. However, Figure 2-16 also shows that the flow-weighted mean phosphorus concentrations

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56 Progress Toward Restoring the Everglades FIGURE 2-13 Changes in the areal extent of tree islands between 1995 and 2004. Yellow Figure 2-13.eps areas show where the islands have expanded, red areas show where they have lost their vegetation, and green areas are unchanged. bitmap SOURCE: F. Sklar, SFWMD, personal communication, 2010.

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The Restoration Plan in Context 57 FIGURE 2-14 Calculated total phosphorus annual loads and annual water inflow volumes to Lake Okeechobee. Figure 2-14.eps bitmap SOURCE: McCormick et al. (2010). FIGURE 2-15 Inflow and average Lake Okeechobee total phosphorus concentrations, calcu- lated from the Lake Okeechobee phosphorus budget, with five-year moving average trend lines. SOURCE: Adapted from McCormick et al. (2010). Figure 2-15.eps bitmap

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58 Progress Toward Restoring the Everglades entering Everglades National Park have increased slightly in recent years. Geo- metric mean total phosphorus (TP) concentrations from the interior of all four regions of the Everglades Protection Area also show mixed trends (Figure 2-17), with increases in Loxahatchee National Wildlife Refuge (LNWR) and Everglades National Park in recent years (Payne et al., 2010b). Additionally, a phosphorus “exceedance” as defined as a violation of the Consent Decree has been reported in LNWR (SFWMD, 2009c; see also STAs in Chapter 3). These data highlight the continuing water quality challenges facing the restoration program and the magnitude of the effort required to address it. Meanwhile, the Environmental Protection Agency has proposed new numeric nutrient criteria for the state of Florida (EPA, 2010) that could broaden the area within the South Florida ecosystem where water quality is under scrutiny. Water quality challenges are discussed in depth in Chapter 5. Avg. Annual Flow-Weighted Mean Inflow TP Conc. (ppb) 200 180 WY1979-1993 W Y1994-2004 160 WY2005-2009 140 120 100 80 60 40 20 0 LNWR (WCA-1) WCA-2 WCA-3 Everglades Natl. Park FIGURE 2-16 Annual average flow-weighted mean total phosphorus concentrations (in ppb) for inflow to the water conservation areas and Everglades National Park. Figure 2-16.eps SOURCE: Data from Payne et al. (2010a).

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FIGURE 2-17 Annual geometric mean TP concentrations (μg/L [or ppb]) for interior areas of the LNWR (WCA-1 or Refuge), Figure 2-17.eps WCA-2, WCA-3, and Everglades National Park (ENP) from WY1978-WY2009. The horizontal lines indicate the average geometric landscape mean TP concentrations for the WY1979-WY1993, WY1994-WY2004, and WY2005-WY2009 periods. Note that unlike Figure 2-16, these data are not flow weighted. 4 bitmaps SOURCE: Payne et al. (2010b). 59

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60 Progress Toward Restoring the Everglades Changes in CERP Since Its Authorization When President Clinton signed the WRDA 2000 he authorized 68 projects extending over 30 years to restore the Everglades. The scope and ambition of the largest restoration plan in U.S. history was testimony to general public and political agreement that the Everglades system was in trouble and that it war- ranted federal (i.e., national) resources to effect its restoration. Disparate interest groups aligned to support the effort, convinced that the ecological and societal benefits of overhauling the Central and South Florida Project outweighed the high cost and large uncertainties. As described in the most recent report of this committee (NRC, 2008), the first eight years after CERP authorization did not come close to expectations. At the federal level there was a sharp loss of political momentum and erosion of congressional support for Everglades restoration; the state of Florida assumed a disproportionate role in funding and moving preferred projects forward. At the same time, the translation of broad restoration goals into specific objectives and projects exposed the differences in priorities among interest groups, and projects grew increasingly susceptible to costly litigation. The cumbersome federal proj- ect planning and approval processes required to receive federal funding became painfully obvious. In short, restoration progress has been far slower than hoped for. Unfortunately, the ecosystem has continued to degrade, the estimated cost of restoration has increased to more than $13 billion, and water supply and flood control challenges have only increased (NRC, 2008; SFERTF, 2009). Nevertheless, many of the individuals who were important in launching the CERP in the late 1990s have continued to dedicate their careers to Everglades restoration. The pool of knowledgeable and experienced personnel has grown both deeper and broader. This expertise is critical in moving projects forward through complex state and federal political and procedural processes. The scien- tific and administrative capacity for implementing the CERP has grown stronger through time, and has benefited from truly excellent scientists in all aspects of Everglades science, both within CERP partner agencies and the scientific community at large. These scientists are continually working to advance the understanding of the condition and functioning of the South Florida ecosystem to further improve the restoration plan as it moves forward (see also Chapter 6). The strength of CERP planners, engineers, scientists, and managers is evident in the CERP progress described in the remainder of this report (particularly the implementation progress in Chapter 3). CONCLUSIONS AND RECOMMENDATIONS This review of the restoration plan and its context 10 years after the CERP was authorized reveals positive as well as negative trends. The South Florida

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The Restoration Plan in Context 61 ecosystem has been fundamentally altered by human modifications of it and by population growth over the past 130 years, and achieving the goals of the ambitious restoration plan remains challenging. The scientific attention that has been brought to bear on the system is impressive and has produced powerful results. Some species, particularly wading birds, Cape Sable seaside sparrows, and panthers appear to be increasing or stable, while others, such as the snail kite, have declined perilously close to extinction. Invasive species continue to present major challenges, even as some of them are being well controlled. Managing water quality and providing the required storage for the restoration continue to be challenging. This committee reaffirms its predecessor’s conclusions (NRC, 2008) that the limited progress made to date, coupled with environmental and societal changes and continued declines of some aspects of the ecosystem, make accelerated progress in Everglades restoration even more important. Delays will continue to jeopardize the success of the restoration enterprise. The com- mitment to long-term scientific activities, including monitoring and assessment, remains essential. The following chapters address these matters in more detail.