The South Florida ecosystem covers about 18,000 square miles in 16 counties and extends from the Kissimmee Chain of Lakes south of Orlando to Lake Okeechobee, and continues south past the Florida Bay to the reefs southwest of the Florida Keys. The ecosystem is in jeopardy today because of past efforts that diverted water from the Everglades to control flooding and to supply water for urban and agricultural development. The Central and Southern Florida project, a large-scale water control project begun in the late 1940s, constructed more than 1,700 miles of canals and levees and over 200 water control structures that drain an average of 1.7 billion gallons of water per day into the Atlantic Ocean and the Gulf of Mexico. This construction resulted in insufficient water for the natural system and for the growing population, along with degraded water quality. Today, the Everglades has been reduced to half its original size and the ecosystem continues to deteriorate because of the alteration of the water flow, impacts of agricultural and industrial activities, and increasing urbanization. Figure 1 shows the South Florida ecosystem before and after the Central and Southern Florida project construction. In an effort to stem the deterioration of the ecosystem and restore the Everglades to a more natural state, federal agencies created the South Florida Ecosystem Restoration Task Force (Task Force) in 1993, an interagency partnership to coordinate federal restoration activities. The Congress formally established the Task Force and expanded its membership in 1996 to include state and local agencies and two American Indian tribes and charged the Task Force with the following responsibilities for restoring the South Florida ecosystem: coordinating the development of consistent policies, strategies, plans, programs, projects, activities, and priorities for addressing the restoration, preservation, and protection of the ecosystem; exchanging information on programs, projects, and activities of the agencies and entities represented on the Task Force to promote ecosystem restoration and maintenance; facilitating the resolution of interagency and intergovernmental conflicts associated with the restoration of the ecosystem among the agencies and entities represented on the Task Force; coordinating scientific and other research associated with the restoration providing assistance and support to agencies and entities represented on the Task Force in their restoration activities. The centerpiece for achieving the goal to get the water right is the CERP, approved by the Congress in WRDA 2000. CERP provides a conceptual framework for increasing freshwater volume and improving the delivery and quantity of water to natural areas in the South Florida ecosystem. It also provides for the region’s other water-related needs, such as water supply and flood protection in urban and agricultural areas. The estimated cost for CERP in 2000 was $8.8 billion, to be shared on an equal basis between the Corps and the state of Florida. Table 1 details the primary purposes for the 60 CERP projects. Before the Corps can proceed with implementing a CERP construction project, WRDA 2000 requires that the Corps obtain congressional authorization by submitting a detailed report on the project’s design, cost, and other information (known as a project implementation report). WRDA 2000 also required the Corps to issue programmatic regulations for implementing CERP projects. These regulations, effective in December 2003, required the Corps, among other things, to take the following actions: Issue no later than December 13, 2004, a master implementation sequencing plan (MISP) that establishes the order in which CERP projects will be planned, designed, and constructed, and periodically update the plan. Issue an interim goals agreement, no later than December 13, 2004, signed by the Secretaries of the Army and of the Interior and the Governor of Florida, for evaluating the restoration’s success and for assessing improvements in the quantity, quality, timing, and distribution of water to restore the natural system. Establish an adaptive management program, which is an approach for addressing the uncertainty associated with project decisions by continuously incorporating new and updated information. Where performance is determined to be less than anticipated, the adaptive management approach allows for making needed changes to the interim goals, projects, and the overall CERP program. Many of the program’s efforts are led by a federal and state interagency science group known as the Restoration Coordination and Verification (RECOVER) team. RECOVER’s responsibilities under the program include assessing and reporting whether interim goals are being achieved, developing monitoring and assessment programs, and preparing technical reports. Agencies participating in the restoration effort are also implementing a number of projects that serve as CERP’s foundation (CERP-related) as well as projects that are not as closely related to CERP (non-CERP). The CERP-related projects are a group of 28 projects, carried out primarily by the Corps and SFWMD, that lay the foundation for the CERP projects. The projects are being constructed throughout the ecosystem and are related to storing, treating, and moving water. The 28 CERP-related projects also include some projects that were authorized in WRDA 1996 and are referred to as Critical Projects for the restoration of the South Florida ecosystem. These water quality and related projects are essential to successfully achieving the goal of getting the water right. The non-CERP projects are a group of 134 projects that are being sponsored by federal, state, local, and tribal agencies in South Florida. A number of these projects had started—and some were completed—prior to WRDA 2000. The projects vary in their purposes, with some involving feasibility studies or plans to control invasive species and others focusing on land acquisition for conservation and restoring habitat. Although these projects are part of the overall restoration of the South Florida ecosystem, their implementation generally does not depend upon other projects. However, certain CERP and CERP-related projects will incorporate portions of non-CERP land acquisitions into their project footprints as the restoration progresses. Among the guiding principles of the South Florida ecosystem restoration initiative is a commitment to managing projects and making decisions on the basis of sound scientific information. Models, particularly mathematical models, are among the tools that agency managers and scientists use to support decision making on the basis of sound science. These models are important to simulate ecosystem changes resulting from restoration activities and to provide managers and scientists with assurance that projects will work as intended to achieve environmental benefits. Managers and scientists use mathematical hydrological, ecological, and water quality models to predict regional or systemwide impacts of project alternatives and to predict benefits that may result from various possible alternatives. To increase the ability of hydrological, ecological, and water quality models to effectively predict environmental benefits and evaluate changes to possible project alternatives, interfaces are needed. Interfaces allow models to share and exchange data and simulate the impact of projects on the ecosystem more comprehensively and effectively. The term interface can cover a variety of mechanisms that allow a model to interact with other models, such as computer software that allows users to simultaneously view the results of multiple individual models, and programs that allow for the exchange of input or output data between models, or allow for hydrological, water quality, and ecological processes to be simulated simultaneously in real time. Forty-three of the 222 projects that constitute the South Florida ecosystem restoration effort have been completed, while the remaining projects are currently being implemented or are either in design, being planned, or have not yet started. Many of the completed projects are intended primarily to improve water quality in natural areas or to acquire or improve tracts of land in order to preserve wildlife habitat. The projects now being implemented also emphasize the restoration of wildlife habitat by acquiring or improving land, as well as the construction of key CERP- related projects that will improve water flow to natural areas. The projects not yet implemented are largely CERP projects that are crucial to realizing the restoration’s overall goals, but these projects are progressing slowly. However, both agency and Task Force officials report a number of achievements, such as finalizing key CERP agreements and restoring a more natural water flow to the Kissimmee River. Table 2 shows the status of the 222 restoration projects. Of the 222 projects the Task Force and participating agencies identified as part of the South Florida ecosystem restoration, 43 have been completed since the beginning of the restoration effort: 9 before 2000 (including 1 as early as 1986), and 34 between 2000 and 2006. However, this latter total is far short of the 91 projects the Task Force and participating agencies reported in 2000 would be completed by 2006. The nine projects completed before 2000 are expected to provide benefits primarily in the area of habitat acquisition and improvement. The primary purposes of the 34 projects completed between 2000 and 2006 range from the construction of stormwater treatment areas, to the acquisition or improvement of land for habitat, to the drafting of water supply plans. (App. II includes detailed information on the 43 completed projects, their sponsors, primary purposes, completion dates, and reported costs; the only projects completed to date belong to the CERP-related and non-CERP categories.) For the 43 completed projects, the three most common primary purposes were water quality, habitat acquisition and improvement, and related studies. For example, to improve water quality SFWMD constructed Stormwater Treatment Areas 1, 2, 3/4, 5, and 6 within the Everglades Agricultural Area located south of Lake Okeechobee. Similarly, for the Cayo Costa project—a habitat acquisition and improvement project— Florida purchased a total of 1,954 acres, over 24 years, in southwestern Florida off the coast of Fort Myers. This purchase is located within a small chain of barrier islands that provide protection for Charlotte Harbor, one of the state’s most productive estuaries. The project’s natural areas demonstrate high species diversity, including some species that may be unique to the islands. Figure 2 shows the types and locations of the 43 completed projects and their primary purposes. Of the 222 ecosystem restoration projects, 107 are now being implemented. Seven of the 107 are CERP projects, 10 are CERP-related projects, and 90 are non-CERP projects.