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Suggested Citation:"2. Findings." National Research Council. 1985. Dredging Coastal Ports: An Assessment of the Issues. Washington, DC: The National Academies Press. doi: 10.17226/608.
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Suggested Citation:"2. Findings." National Research Council. 1985. Dredging Coastal Ports: An Assessment of the Issues. Washington, DC: The National Academies Press. doi: 10.17226/608.
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Suggested Citation:"2. Findings." National Research Council. 1985. Dredging Coastal Ports: An Assessment of the Issues. Washington, DC: The National Academies Press. doi: 10.17226/608.
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Suggested Citation:"2. Findings." National Research Council. 1985. Dredging Coastal Ports: An Assessment of the Issues. Washington, DC: The National Academies Press. doi: 10.17226/608.
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Suggested Citation:"2. Findings." National Research Council. 1985. Dredging Coastal Ports: An Assessment of the Issues. Washington, DC: The National Academies Press. doi: 10.17226/608.
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Suggested Citation:"2. Findings." National Research Council. 1985. Dredging Coastal Ports: An Assessment of the Issues. Washington, DC: The National Academies Press. doi: 10.17226/608.
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Suggested Citation:"2. Findings." National Research Council. 1985. Dredging Coastal Ports: An Assessment of the Issues. Washington, DC: The National Academies Press. doi: 10.17226/608.
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Page 10
Suggested Citation:"2. Findings." National Research Council. 1985. Dredging Coastal Ports: An Assessment of the Issues. Washington, DC: The National Academies Press. doi: 10.17226/608.
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Suggested Citation:"2. Findings." National Research Council. 1985. Dredging Coastal Ports: An Assessment of the Issues. Washington, DC: The National Academies Press. doi: 10.17226/608.
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Findings 1. DOES THE UNITED STATES NEED ADDITIONAL PORT CAPACITY TO ACCOMMODATE LARGER SHIPS? Finding 1: The United States should act expeditiously to increase its capacity to handle large ships. Two general categories of need exist: first, the capacity to accommodate liquid- and dry-bulk carriers of between 90,000 DWT and 150,000 DWT (or more); and second, a capacity to accommodate such modern vessels as the latest-generation containerships, which require water depths of 40 ft to 45 ft. Several facts and trends lead to this finding: Large vessels offer economies of scale. Large liquid- and dry-bulk carriers (100,000 DWT and more) now dominate world trade in several commodities, and are rapidly increasing their share of other commodity movements T ~ ~ ~ _ · ~ _ ~ ~ ~ ~ ~ Large Aqua- ana ary-ou'~ carriers cannot transit the major ports of the Atlantic or Gulf coasts fully loaded. (There is some deep-water loading/unloading capability on the Pacific Coast.) · Many major ports of the United States cannot easily accommodate the range of medium-size vessels--for example, those designed to the maximum dimensions allowed by the Panama Canal, and the latest-generation containerships--a range requiring water depths of 40 ft to 45 ft (or more). A substantial number of ports worldwide have the capacity to accommodate large ships, and several more are planning or developing this capacity. Some combatant vessels, and (increasingly) the commercial vessels that would be relied on to support any major defense mobilization require greater water depths or widths than are now provided in some designated defense ports. Future patterns of trade and the vessels that will carry that trade are uncertain. In the face of uncertainty, prudence dictates having sufficient flexibility to respond rapidly to a range of possible developments. 4

5 2. WHAT ARE THE MOST ATTRACTIVE WAYS FOR THE UNITED STATES TO ACCOMMODATE LARGE SHIPS? Finding 2: The preferred options for developing additional capacity to handle large ships are: (1) dredging existing multicommodity ports and (2) lightering/topping-off. For a range of vessels and cargoes, there is no adequate alternative to conventional ports and harbors for loading or unloading. Existing ports offer sheltered water for unloading or loading without delay, access to developed storage and cargo transfer facilities, well-developed connections to inland transportation, and established worldwide marketing networks. Dredging to increase the capacity of existing ports yields maximum future flexibility to respond to changes in trade, and to support defense mobilization, as well as offering the broadest base for recovering the cost of dredging and distributing the benefits. Several alternatives to dredging existing ports are specific to one or more bulk commodity. The attractiveness of these options depends on several factors such as location, commodity, and volumes to be handled that can only be evaluated or compared in specific proposals. The lowest-cost alternative to dredging is lightering/topping-off. This alternative already exists in the United States, and offers a flexible response to the need to load and unload bulk carriers in some contexts. Finding 3: The nation needs to assure, on an accelerated basis, the existence of permanent, multipurpose port capacity to handle bulk vessels requiring at least 50 ft of water depth on each of the coasts. Finding 4: If federal funding is involved, the choice of which ports to deepen to 50 ft or 55 ft or more is particularly important because the high cost of port construction and maintenance and present uncertainty associated with need suggests that only a limited number of such port deepening activities are warranted. Selection of port deepening projects should consider four criteria: (1) Emphasis should be given to dredging ports that handle all types of cargoes, and therefore, a variety of vessels--containerships, roll-on/roll-off ships, break-bulk vessels, and both liquid- and dry-bulk carriers. (2) Major attention should be paid to the port's inland transportation systems. Two factors are important here. First, the most attractive ports would be those serving a broad range of economic activities, from manufacturing to agriculture to mining, as well as serving large populations or markets. Second, wherever possible, the port should be served by multiple inland transportation systems. The ideal would be ports served by multiple rail lines, highway transportation, and inland waterway transportation. Such multiple inland transportation options offer a competitive environment which should serve to keep inland transportation costs low. (3) Consideration should be given to the costs of construction and maintenance dredging. Particular emphasis should be placed on minimizing maintenance dredging since it is a recurring cost. (4) Ports should be judged in terms of the

6 environmental consequences of dredging. To the extent that environmental consequences can be reduced and other criteria satisfied, the optimum situation would exist. Finding 5: The navigational facilities of some major ports need to be enlarged by dredging to handle the range of medium-size vessels requiring 40 ft to 45 ft of water depth (or more). Dredging existing ports to handle Panamax vessels and the latest-generation containerships requires less dredging than that required for larger vessels. If federal funding is involved, emphasis should be given to ports that handle all types of cargoes, as a variety of vessels in the world fleet require water depths of 40 ft to 45 ft. Attention also needs to be given to the ports' inland transportation system, to populations and inland markets served, to the comparative costs among the candidate ports of construction and subsequent maintenance dredging costs, and to the environmental consequences (that is, emphasis needs to be given to the reduction of potentially adverse consequences and the demonstration of environmental benefits in selecting dredging projects). Finding 6: Lightering/topping-off should be encouraged. Even on an accelerated basis, dredging projects will take time. Where needs now exist to accommodate large bulk carriers, lightering/topping-off can be implemented with speed and flexibility. Private-sector investments have already been made in these systems, and where their use is attractive, it should be encouraged. In sum, the committee concludes that the nation will have adequate flexibility to handle bulk commodities in the future with (at a minimum) deep-draft capacity on each coast and lightering/topping-off capability, and medium-draft capacity in some major ports. 3. HOW SHOULD DREDGING BE FUNDED, AND WHAT ARE THE IMPLICATIONS FOR DREDGING OF VARIOUS FUNDING APPROACHES? Finding 7: Some form of federal funding is warranted, given the importance of enhanced port capacity to the nation's economic well-being, and national security/defense needs. Ports are a national resource. The U.S. and world economies are increasingly interdependent, and most trade among nations is oceanborne. Enlarging the physical capacity of U.S. ports could make our exports more competitive and reduce the landed cost of imports. These conclusions, as well as the potential role of ports in national security and defense, argue for some continued federal funding. Finding 8: Congressional consideration of port projects should be independent of other water resources projects, and Congress should identify the criteria to be used in selecting among competing projects for which there is a federal funding role.

7 Finding 9: Resolving the funding stalemate will require addressing the following issues: (1) the sources of revenue, (2) who will collect the revenues, (3) how the revenues will be allocated, (4) who will handle the management and implementation of port dredging, and (5) what the preceding four changes will mean for the management and regulatory approval process associated with port dredging projects. It is important that Congress address all these issues if port dredging is to be expedited. 4. WHAT ARE THE CAUSES OF THE SLOWDOWN IN DECISION MAKING FOR LOCAL PROJECTS AND THE STALEMATE FOR FEDERAL PROJECTS, AND WHAT ARE THE WAYS OF BRINGING INCREASED SPEED, PREDICTABILITY, AND STABILITY TO THE DECISION MAKING PROCESS? Finding 10: The complexity of the institutional decision making system for port dredging reflects the need to address and manage a large and difficult set of real needs and concerns. But the system does not allow timely port development, either of federally or locally funded projects. Actions need to be taken by Congress, the regulatory agencies, and the ports to achieve speed, predictability, and stability in decision making, as suggested in succeeding findings. Findina 11 Ports need to establish mechanisms and procedures for developing and evolving comprehensive port plans. In general, regulatory decisions governing port dredging have only been made when consensus is achieved--that is, when no significant participants have objected so strongly to proposed action that they are willing to mobilize and oppose it. A planning process is the essential beginning of continuing consensus-building for ports. Any planning process needs to identify the needs of the port both in the short and long term and the implications of those needs for the range of concerns reflected by the interested parties. The planning mechanism or process, then, needs to include all the appropriate governmental agencies as well as port users, commercial interests, and environmental and public interests concerned about port development. Since each port is unique, what is required will vary from port to port, but given the complexities of the issues that now surround port decision making, any route other than a local consensus building mechanism appears to offer little chance of success. Finding 12: Resolving environmental issues in a timely fashion has a direct bearing on the economics of a dredging project. Delays occasioned by the actual or perceived failure to address environmental concerns adequately can result in significantly increased costs, which may undermine or negate the economic benefits expected from the dredging projects--and even in the abandonment of worthwhile projects. Finding 13: In the interests of preserving the right of those with strongly held objections to have their day in court, while not

8 subjecting project proponents to unreasonable and protracted opposition, Congress should consider placing appropriate time limits on the ability to seek judicial review once a final regulatory decision has been made on a port dredging project. Finding 14: A review of existing dredging-related regulations needs to be undertaken to determine their consistency with the intent of federal law, their necessity, efficacy, and clarity. Finding 15: New procedures are needed to allow the comments of state and federal agencies on proposed dredging projects to be consolidated to the extent possible, both for the review of environmental impact statements and for the review of permit applications (that is, for both federally and locally funded projects). Finding 16: A comprehensive interagency agreement needs to be developed for consistent and timely consideration of environmental mitigation by all agencies commenting on dredging or filling projects under the Fish and Wildlife Coordination Act. In addition, each U.S. Fish and Wildlife Service region should be given the authority and responsibility to develop a regional mitigation plan with specific resource management goals to guide the formulation of project-specific mitigation requirements. Finding 17: In the formulation of project-specific requirements, regulations should clearly state that wildlife resource agencies include and consider the economic costs and environmental benefits of mitigation proposals. At a minimum, these agencies need to demonstrate that mitigation (1) will achieve significant benefits for environmental resources within the statutory authority of the commenting agency, (2) is reasonably available to the applicant, and (3) is feasible and practicable. 5. WHAT ARE THE PROBLEMS ASSOCIATED WITH DESIGN AND IMPLEMENTATION OF DREDGING PROJECTS, AND HOW CAN THEY BE DEALT WITH? Finding 18: The design of new construction and dredging projects is impeded by the length and character of the decision making process. As proposals age, the world fleet and port structures change, but engineering redesign is confined to the limits of project authorization, if the proposal is approved. Systematic port engineering is discouraged by the length and fragmentation of institutional processes. Finding 19: Safety margins that would otherwise be provided by engineering are in many ports now provided by compensating operational practices. Because there are as yet no consensus standards for navigational safety, the design of new construction and ongoing maintenance

9 dredging projects should be carried out with full cooperation and coordination among all relevant interested parties: the U.S. Army Corps of Engineers, U.S. Coast Guard, harbor pilots, shipowners and other shipping interests, to ensure local consensus on navigational safety. Finding 20: Design, layout, and dimensions of dredged navigational facilities must be site-specific. The consensus standards developed by international organizations should be adopted as general guidelines, where applicable. Better understanding can and should be gained of vessel maneuvering characteristics, and efforts need to be made to improve and use the techniques and tools of design analysis for accommodating vessels; e.g., the full-scale vessel simulator of the U.S. Maritime Administration. Techniques and tools are well developed for observing and modelling local circulation and sedimentation (cf. Finding 24~. The use of these sets of tools needs to be encouraged. Finding 21: The use of existing state-of-the-art dredging plant needs to be encouraged, and impetus given to developing needed modern capability. Finding 22: Contracting with private dredging companies should be handled to achieve maximum efficiency and optimum use of resources. Improvements can be made by providing long-term dredging contracts that allow dredging contractors to make investments in equipment offering greater efficiency. Review of procurement and other procedures may suggest further revisions to reduce costs, maximize efficiency, or both. 6. WHAT ARE THE MAJOR ENVIRONMENTAL PROBLEMS ASSOCIATED WITH DREDGING AND HOW CAN THEY BE MOST EFFECTIVELY MANAGED? Finding 23:Since dredging leads to disposal, the two activities are tightly coupled. The potentially undesirable environmental effects of the two activities are quite different, however. The potential for persistent undesirable effects associated with the dredging of materials for maintenance is very small, regardless of the character and quality of materials dredged. The potential for persistent undesirable effects associated with the disposal of these materials may be significant. It is a function of the quality of materials dredged, their physical characteristics, and the levels of associated contaminants. ~ The potential for persistent undesirable effects associated with the dredging of material for new work may be significant. It is a function of the quantity of material dredged, the changes in channel geometry, and the local hydraulic regime. The potential for persistent adverse environmental effects associated with the disposal of this material, on the other hand, is small.

10 Scientific understanding of the environmental effects of dredging and dredged-material disposal is sufficient to enable predictions of the short- and long-term effects of maintenance and construction dredging, and, at least, the short-term effects of disposal with a level of accuracy sufficient to ensure adequate environmental protection. Finding 24: The greatest potential for environmental problems associated with dredging is with construction dredging, which can produce persistent and significant changes in the hydraulic regime as a result of channel deepening. The potential for such effects requires particular attention in estuaries, where changes in cross-sectional geometry can alter estuarine circulation patterns and as a result, the distribution of salinity, dissolved oxygen, and other important environmental parameters. The greatest potential for environmental problems associated with disposal of dredged materials is associated with maintenance materials which contain moderate to high concentrations of toxic material. Typically, this contaminated fraction constitutes a relatively small percentage of materials removed, and enough is known to select appropriate disposal options to contain the contaminated material and thereby minimize the potential for adverse effects. Finding 25: Sedimentation within many port areas is significantly affected by sediments introduced by the activities of man, including construction, farming, and a variety of municipal and industrial discharges. Greater efforts should be made at the federal, state, and local levels to control these sources throughout the tributary drainage basin. Finding 26: Parallel efforts should be made to reduce or eliminate inputs of toxic contaminants entering drainage basins and rivers or estuaries leading to ports. The costs of controlling toxic contaminants at the source may very well be less than those associated with the disposal and management of toxic materials dredged from ports. For existing contaminated sediments, a properly designed and executed program of dredging and containment may have beneficial environmental consequences. Finding 27: A comprehensive dredging and dredged-materials management plan should be developed for each port with a specific long-term objective being to assure that maintenance projects can be carried out on schedule while minimizing adverse environmental effects. The plan should be based on: (1) a thorough characterization of the kinds and qualities of material to be dredged, (2) a detailed determination of the spatial distribution of contaminants (both horizontally and vertically) within channel deposits that permits definition of the degree of homogeneity in the sediments to be dredged and to delineate prominent contaminant "hot spots," (3) a rigorous assessment of the physical and chemical behavior of these materials if placed in each of the alternative disposal environments, (4) con

11 sideration of beneficial use (cf. Finding 29) as an alternative, (5) an assessment of the effects resulting from each of the dredging and disposal alternatives for public health, the environment, the biota, other uses of that segment of the environment, and the relative costs, and (6) consideration of long-term continuing costs and effects associated with the plan. Such a plan should eliminate the need for a complete new assessment every time a maintenance project is scheduled. Given that the material accumulating within any development area varies little over relatively long periods of time (unless there is a major spill or other accidental release of contaminants, or natural event such as a flood or violent storm), analysis of representative materials should be sufficient to determine whether the quality of sediment falls within the normal range. Careful development of a dredging and dredged-materials management plan should reduce, if not eliminate, the need for repeated bioassay and bioaccumulation tests. Finding 28: From the point of view of environmental protection, a major problem associated with regulatory procedures and criteria is their lack of responsiveness to new information about the environmental effects (positive and negative) of dredging and the disposal of dredged material. Far more is known about environmental effects and probable causes than is incorporated in present regulatory criteria. Thus, streamlining the regulatory process is necessary--not just for port management, but for the improvement of regulatory criteria. Finding 29: Dredged sediment should be regarded as a resource rather than as a waste. Materials should be carefully screened to determine suitability for use as construction aggregate, sanitary landfill cover, for beach replenishment, for the creation and enhancement of wetlands, and for other uses prior to disposal. The attractiveness of these alternatives, as well as a balanced assessment of upland sites versus ocean sites for disposal, would be encouraged if the "local cooperation" policy of the U.S. Army Corps of Engineers were modified. That policy requires that the project proponents assume responsibility for "all necessary lands, easements, and rights of way" for upland sites in addition to ongoing operation and maintenance costs. Such responsibilities, not required of users of ocean disposal sites, limit the attractiveness of the upland alternative independent of benefits that might be realized. Finding 30: Designated containment sites, whether specially constructed (e.g., diked alongshore structures, containment islands, or upland containment facilities) or remnants of previous commercial activity (e.g., subaqueous borrow-pits), should be reserved for the disposal of dredged materials known to be contaminated with toxic compounds.

12 Contaminant-free sediments should be placed within these areas only as cover or "capping" materials, and every effort should be made to minimize the volume occupied by these clean materials. Storage of contaminated sediments in these sites should be managed so as to maintain a physically and geochemically stable environment, to minimize the exposed surface area of the deposit, and to preserve essentially anaerobic conditions. Finding 31: Characterization and designation of ocean disposal sites by the Environmental Protection Agency should be completed as rapidly as possible. The present use of historical disposal areas does little to minimize the probability of adverse short-term effects and may ultimately result in long-term continuing problems. So long as ocean disposal sites are not officially designated, it is difficult to justify detailed analyses of sediments, since these analyses have little influence on management of the sediments. Finding 32: The approach that characterizes many studies of the environmental effects of dredged-material disposal needs to be modified. There should be reduced emphasis on survey techniques (counting, sorting, diversity, and the like) and more emphasis on biological response, including physiological processes. There is a particular need for some reasonably long-term studies modelled on the lines of ongoing public health or epidemiological research. Associated with the initiation of these studies should be the termination of the majority of the short-term investigations typically associated with Environmental Impact Statements (EIS). While the EIS process continues to represent a valuable component of over-all environmental management and regulation, it has been reasonably well demonstrated that routine field and laboratory studies lack the resolution required to detail all but the most evident acute effects. Finding 33: Procedural specifications used within federally sponsored dredging projects should increasingly encourage the use of high-efficiency dredges and dredging techniques specifically intended to reduce sediment loss and associated turbidity during dredging and to provide routine, highly accurate placement of dredged materials. Where predredging surveys indicate contaminated "hot spots," selective dredging and disposal techniques should be used. These techniques need to be considered in contracting for dredging plant (cf. Findings 21 and 27~.

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Are the nation's ports adequate for our present and future needs? This volume points out that no significant new deep-water construction has occurred for a decade, and provides the information and analysis needed to goad the ports and the federal government into action. The book asks three questions: Is additional port construction and maintenance dredging needed now or over the next 20 years? What would prevent dredging if it is needed? What alternatives could make additional dredging possible? The book identifies several problems in dredging ports, including the long interval between a decision to deepen a port and the time the alterations are complete. The United States needs to speed port construction to meet changing needs, and the committee recommends that we prepare for future needs by dredging now.

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