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MAINTENANCE DREDGING John Downs Dredging serves the objectives for which ports and harbors (and by inference, their entrances) are designed and constructed, by creating and preserving specified configurations of channels and sheltered areas for the safe conduct of marine traffic. Dredging operations remove the materials, principally soils, that collect on the bottoms of these areas. These seemingly simple tasks, conducted in the marine environment, demand large capital investment in equipment. A sufficiently clear set of national objectives is needed to allow the specification of equipment, its acquisition, and plans for the order and management of operations to be carried out well in advance of undertaking these tasks. An important aspect of the national objectives affecting dredging is a set of guidelines for the delivery or disposal of dredged materials. In day-to-day operations, the same kinds of physical environmental information required by mariners are vital to the operators of dredging operations. Thus, the subjects addressed in the three categories of this meetings' concerns--design and maintenance, the concerns of ships and users, and nature and the environment--are all important to dredgers, and the operations of dredgers are important to realizing (or failing to realize) the objectives that might be set in thee categories. These facts would seem to dictate the closest collaboration of all interested parties, yet there is a critical lack of integrated planning and management of this country's ports and harbors. The nation faces serious imbalances in the energy resources it imports, such as foreign oil, and its abundant energy resources for which there in growing foreign (and little domestic) demand, namely coal. Resource economists agree that no ready substitutions will replace imported oil for the next ten to fifteen year". other nations are fully prepared with large ships and deep-draft receiving facilities for our coal. Yet, this country has no deep-draft harbors sufficient to this much needed trade. Viewed from the national level, plans and actions to create deepwater ports, or offshore facilities, have been spasmotic. The critical lack of communication and coordination is evident in the long-standing concerns the dredging industry and the U.S. Army Corps of Engineers, environmentalists and preservationists, and citizens have long had for the effects of various means of disposing of dredged materials. After an intensive five-year study of all aspects 39

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40 of this subject that included the development of a new piece of equipment to reduce turbidity, careful monitoring of specific disposal methods in well-studied sites, and the publication of more than 100 documents (including guidelines for the multitude of various situations that might be faced), the results are still unknown to the state and local governments that have held up improvements to ports and harbors that imply significant dredging. The disposal of dredged materials with care and judgment can be beneficial or innocuous to the environment--restoring eroded beaches and creating new habitats, or harmlessly entering the deep ocean. Contaminated materials need special care, and the disposal of these is addressed in detail in the reports of the Dredged Materials Research Program reports (sometimes called the "WES reports because they were supervised by the Waterways Experiment Station of the U.S. Army Corps of Engineers). There is some resistance to these reports, where they are known, owing to an inferred conflict of interest in the Corps' having supervised them. Although the studies were coordinated with the U.S. Environmental Protection Agency, the Corps of Engineers is both a dredger and a major contractor for dredging services, and there is some feeling that the Corps' environmental assessments cannot but serve the interests of continued dredging. Coordinated planning and management of port and harbor projects would allow environmental and economic interests to be aired and afford better opportunities for satisfying both. On faith alone, for example, that the country would realize its pressing need for improved facilities, the dredging industry has invested large sums in up-to-date equipment. These are now being deployed in projects worldw~de-- projects far more sophisticated than any undertaken here--but the anticipated domestic activity has not yet begun. The present situation is that supertankers and large cargo ships requiring drafts of 60 feet or more cannot enter our ports and harbors. The maximum permissible drafts of our domestic ports and harbors are 38 to 43 feet. Some state and local governments and port authorities have advanced plans to deepen facilities, or to improve their dimensions. These plans are frequently frustrated by the financial arrangements necessitated by legislation for suab public works, assuming the plans pass all the other obstacles and tests. Summary The problems faced in the prosecution of maintenance dredging programs are principally administrative and political, not technical. Several companies in the industry have scheduled work that later could not proceed for lack of necessary permits. Much of the legislation seeking to protect the environment from the effects of dredged materials appears now, in the light of comprehensive studies, to have been premature. The nation has urgent needs to improve the dimensions of its port and harbor facilities, and it has been demonstrated, but not communicated widely, that careful site-by-site evaluations and judgments can be employed to prevent significant harm to the

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41 environment from dredged materials. Yet, the lack of coordinated planning and management of these harbor and port developments results in failure to follow through in action. DISCUSSION HERBICH: Over the years I have heard comments about the obsolescence of both the government and the private sector dredges What is your opinion of their present status? DOWNS: I won't comment on the public sector's dredges. I will say for the private sector that tens of millions of dollars have been spent in the last few years in the optimistic hope that ports will be maintained and that this country will continue to build new or improved ports and harbors. Our role, as directed by the Congress, is to conduct as much of this activity as we possibly can, under the direction and management of the Corps. I don't think there is any question that we can compete in the world today, as we have shown by going overseas to work. A great deal of money has been spent in other areas of the world. The Dutch have spent 100 million dollars on one dredge. We cannot meet this capability because there are no projects here that will support it. BERTSCHE: Would it be appropriate in the design of new ports or for major modifications to ports to plan initially where the maintenance dredging spoils would be disposed of, or is that done now? DOWNS: I wouldn't want to go so far as to say all maintenance dredging would be disposed of in the same place. Different materials demand different treatment. Certain virgin materials are put on designated islands. Bird sanctuaries have been created on some of these islands. HERBICH: Suppose that there were three new harbors authorized, say, Galveston, Corpus Cbristi and perhaps another in the same area? Would the private sector have sufficient capacity to handle dredging or deepening of these three harbors? DOWNS: When the contract comes out, the port authorities may want it done in 18 months, 20 months. We have tried to talk them into three seasons, which would be a little over 24 months, or perhaps 30. The timing of dredging operations is always critical: having the right set of dredges and other equipment at the right place, on time. In the instances you name, existing equipment could perform the closer-in work, and development could proceed for the equipment needed for the outer, deepwater portions. This equipment ha" been designed, and manufacture could proceed if the market were evident. For this equipment to be developed in a timely way, careful planning is necessary. Industry is looking forward to preparing for these developments, and T think it will not be found lacking.

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