Advisers to the nation on Science, Engineering, and Medicine

National Academy of Sciences

National Academy of Engineering

Institute of Medicine

National Research Council

The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. On the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Bruce M. Alberts is president of the National Academy of Sciences.

The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. William A. Wulf is president of the National Academy of Engineering.

The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an adviser to the federal government and, upon its own initiative, to identify issues of medical care, research, and education. Dr. Kenneth I. Shine is president of the Institute of Medicine.

The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy’s purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both the Academies and the Institute of Medicine. Dr. Bruce M. Alberts and Dr. William A. Wulf are chairman and vice chairman, respectively, of the National Research Council.

The Transportation Research Board is a unit of the National Research Council, which serves the National Academy of Sciences and the National Academy of Engineering. The Board’s mission is to promote innovation and progress in transportation by stimulating and conducting research, facilitating the dissemination of information, and encouraging the implementation of research results. The Board’s varied activities annually engage more than 4,000 engineers, scientists, and other transportation researchers and practitioners from the public and private sectors and academia, all of whom contribute their expertise in the public interest. The program is supported by state transportation departments, federal agencies including the component administrations of the U.S.Department of Transportation, and other organizations and individuals interested in the development of transportation.

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Environmental windows are those periods of the year when dredging and disposal activities may be carried out because regulators have determined that the adverse impacts associated with dredging and disposal can be reduced below critical thresholds during these periods. Environmental windows, therefore, are used as a management tool for reducing the potentially harmful impacts of dredging activities on aquatic resources. The first environmental windows were established more than 30 years ago and, according to the U.S. Army Corps of Engineers (USACE), are applied today to more than 80 percent of all federal dredging projects. Given the cumulative restrictions on dredging operations resulting from the application of environmental windows, USACE requested that the National Research Council’s Transportation Research Board (TRB)— Marine Board conduct a workshop to explore the decision-making process used to establish environmental windows, as well as the consistency of the windows-setting process. The statement of task for the workshop is included in Chapter 1.

The National Research Council established the Committee for the Workshop on Environmental Windows for Dredging Projects to design, oversee, and interpret the results of the workshop. Formed in June 2000, the committee comprised 12 members representing ports, dredging contractors, benthic and wetland ecologists, commercial fisheries experts, sedimentologists, ichthyologists, environmentalists, and state and federal regulatory agencies. During the course of a 1-year period, the committee met three times—the first to plan the workshop, the second to review the workshop results, and the third to prepare the committee’s findings and recommendations presented in this report. Members of the committee also participated in the Sea Grant Conference on Dredged Material Management: Options and Environmental Considerations and organized and participated in a half-day session at the 2001 National Dredging Team Conference.

The committee used information obtained through case studies and outreach efforts conducted in preparation for the workshop to develop a draft template for a process for setting, managing, and monitoring environmental windows. This

draft template was presented during the workshop, held March 19–20, 2001. Participants at the workshop represented a cross-section of stakeholders involved in the windows-setting process, including federal and state government officials, port officials, representatives from environmental interest groups, dredging contractors, and academic experts from a variety of relevant fields. A listing of the workshop participants is provided in Appendix C. The draft template was reviewed and refined throughout the course of the workshop, and a summary of the workshop proceedings including the refined template was distributed to participants expressing a willingness to review and comment on its accuracy.

The committee wishes to acknowledge the contributions of many individuals and organizations to the development of this report. Kris A. Hoellen managed the study and drafted the report under the guidance of the committee and the supervision of Stephen R. Godwin, Director of TRB’s Studies and Information Services Division. Susan Roberts provided liaison support from the Ocean Studies Board, Thomas Bigford served as liaison from the National Oceanic and Atmospheric Administration (NOAA), and Douglas Clarke served as liaison and project sponsor from USACE; all three provided background materials and valuable insights to the committee.

The committee also wishes to thank the organizers of the National Dredging Team Conference and the Sea Grant Conference on Dredged Material Management: Options and Environmental Considerations for allocating space and time for the committee’s outreach efforts. In addition, the committee would like to acknowledge personnel from USACE and NOAA who developed case studies that documented their experiences with environmental windows.

The workshop benefited greatly from the contributions of a reaction panel whose members provided much-needed advice and guidance during critical points in the proceedings. Panel members were Suzanne Schwartz (U.S. Environmental Protection Agency), Thomas Bigford (NOAA), Joseph Wilson (USACE), and Robert Van Dolah (South Carolina Department of Natural Resources). Finally, the committee is indebted to all those who participated in the workshop for both their time and continued interest.

This report has been reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise, in accordance with procedures approved by the National Research Council’s Report Review Committee. The purpose of this independent review is to provide candid and critical comments that will assist the institution in making the published report as sound as possible and to ensure that the report meets institutional standards for objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process.

The committee thanks the following individuals for their review of this report: Steven Goldbeck, San Francisco Bay Conservation and Development Commission; H. Thomas Kornegay, Port of Houston Authority; Charles A. Simenstad, University of Washington; and Ancil Taylor, Bean Stuyvesant LLC. Although these reviewers provided many constructive comments and suggestions, they were not asked to endorse the findings and conclusions, nor did they see the final draft before its release.

The review of this report was overseen by Lester A. Hoel, University of Virginia. Appointed by the National Research Council, he was responsible for making certain that an independent examination of this report was carried out in accordance with institutional procedures and that all review comments were carefully considered. Responsibility for the final content of this report rests entirely with the authoring committee and the institution.

Suzanne Schneider, Assistant Executive Director of TRB, managed the report review process. The report was edited and prepared for publication under the supervision of Nancy Ackerman, Director of Reports and Editorial Services. Rona Briere edited the report. Special thanks go to Frances Holland for assistance with meeting arrangements and to Alisa Decatur for production of the final report.

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