A Review of the Florida Keys Carrying Capacity Study (2002)

The Florida Keys are the third largest barrier reef ecosystem in the world and the only one of its kind in the United States. Given the area’s ecologically rich, culturally significant, and environmentally sensitive nature, the State of Florida designated the Florida Keys as an Area of Critical State Concern in 1975 (Florida Statute, 1986; Florida Administrative Code §28-29, 1975). As a result of this designation, Monroe County, which includes the Florida Keys, must meet strict planning standards in order to address future development and to sustain the unique resources and quality of life that exist in the Keys.

In the early 1990’s, the Monroe County Board of Commissioners developed the Monroe County Year 2010 Comprehensive Plan adopted in 1993 (Monroe County Growth Management Division, 1993). Over a four-year period the plan was subjected to legal challenges that highlighted several aspects of the Florida Keys ecosystem as potential “carrying capacity indicators,” including the near-shore water quality, the health and extent of native seagrasses, population and distribution of the endangered Key deer, and hurricane evacuation capability.

After a lengthy process of public debate and legal proceedings, the Florida Administration Commission and the Governor issued Rule 28.20-100 in 1996, which contains a five-year work program for Monroe County (Florida Administration Commission Rule 28.20-100, 1996). This rule required the completion of the Florida Keys Carrying Capacity Study (FKCCS) and its companion, the Carrying Capacity Analysis Model (CCAM). According to the Rule, the CCAM was to be designed “. . . to determine the ability of the Florida Keys ecosystem,

and the various segments thereof, to withstand all impacts of additional land development activities.” Both the FKCCS and the CCAM are sponsored by the U.S. Army Corps of Engineers (USACE) and the Florida Department of Community Affairs (FDCA) and are contracted out to the URS Corp., Inc. Since this is the first time that a comprehensive analysis of this type has been carried out in Florida, the outcome is of great interest to local officials and to the general public. Recognizing the need for an authoritative, independent technical review, the USACE and the FDCA requested that the National Research Council establish a committee to undertake this task.

The appointed committee (Appendix A) was charged to review and evaluate the scientific methods, principles, and data that form the basis for the Florida Keys Carrying Capacity Study and the accompanying Carrying Capacity Analysis Model being developed by the State of Florida. In addition, the committee was asked to assess the ability of the FKCCS to fulfill its stated goal of “determining the ability of the Florida Keys ecosystem to withstand all impacts of additional land development activities,” and to determine the extent to which the conclusions were reached based on a sound scientific process.

The committee was specifically charged to review and comment on the following:

• the overall design assumptions;

• the data used;

• the requirements, responses, limiting factors, and thresholds for the study categories selected;

• the determination of how land development activities will affect study categories; and

• the adequacy and reliability of the study as a basis for local and state land management and planning decisions.

To provide rapid feedback to the project managers the committee first produced an Interim Review of the Florida Keys Carrying Capacity Study (National Research Council, 2001; Appendix B). That report was based on presentations made by contractors from the URS Corporation and their discussions with the NRC Committee at a two-day workshop held in Key Largo, Florida, on January 9–10, 2001, where they described the progress to date in designing the CCAM.

In late November 2001, the USACE and the FDCA submitted the Florida Keys Carrying Capacity Study: Test Carrying Capacity Analysis Model First Draft, (hereafter referred to as the Draft CCAM), to the NRC committee for review (URS Corporation, Inc., 2001a). The committee was then given 13 weeks to assess the Draft CCAM and submit a review based on the charge outlined

above. This time limit allowed the committee to review the Draft CCAM Report with some degree of thoroughness but prohibited a careful assessment of the inner-workings of the model, examination of input data, or comparison to similar modeling endeavors elsewhere. All parties involved recognized that the Draft CCAM document was not a final version and understood that changes would be made in the final draft of the CCAM. The Draft CCAM submission included a series of appendices outlining terminology, acronyms, formulas, and explanation of the methodology used in the Marine Module. The NRC Committee requested several supplementary documents cited in the Draft CCAM for review and clarification that are listed at the end of the report. In addition, the committee submitted a set of over 150 questions to the contractors at URS Corp., for which they provided written answers prior to attending a public meeting with the committee in January 2002 (Appendix D).

The remainder of this report is organized into ten sections and four appendices. Section 2 provides an overview of the committee’s crosscutting concerns relating to all of the Draft CCAM modules. Sections 3–9 contain comments on each individual module (Scenario Generator, Socioeconomic, Fiscal, Human Infrastructure, Integrated Water, Marine, and Terrestrial). The final section, 10, contains the committee’s overall conclusions. Several appendices provide background information and a glossary. Appendix A contains committee member biographies; Appendix B presents the Interim Review of the Florida Keys Carrying Capacity Study; Appendix C provides a glossary of terms and acronyms; and Appendix D contains both detailed comments on the Draft CCAM and the questions submitted by the committee in December 2001 and the contractor’s responses, provided in January 2002.