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2 REGULATORY AND INSTITUTIONAL CONSIDERATIONS Background The legislative and regulatory structure governing dredged navigational channels reflects a long history. A summary volume of regulations states that "since colonial times, harbors and channels have played an Important role in the nation's settlement, commercial and industrial growth, and system of defense" (U.S. Army Corps of Engineers, 1981a). As the provision of dredged navigational channels has been taken to be a federal responsibility of both military and commercial importance, primary responsibility for the design and maintenance* of these works has been taken by the O.S. Army Corps of Engineers. In recent decades, other national interests have increased in public importance, notably those of protecting the marine and coastal environment and preserving oceanic resources. (A summary of *Until 1978, the U.S. Army Corps of Engineers also performed improvement and maintenance dredging with its own fleet of dredges, and by contract with private industry. In 1978, following the Industry Capability Program and a congressional act (P.L. 95-269), the Corps initiated a Minimum Dredge Fleet for purposes of national security or defense, preserving sufficient work to keep the fleet operational, and allowed private industry to bid on all other dredging work. 2 - 1

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2-2 environmental protection laws requiring compliance in navigational projects is given in Appendix C.) Among the environmental questions raised about dredging are the immediate and long-term effects of the activity, the location of onshore or of fshore disposal sites for dredged materials of different types, and the handling and disposal of dredged materials containing toxic or hazardous substances, such as Depone, oil, and heavy metals . A lengthy 20-step process for gaining approval and public funds for the construction of navigational projects has evolved in response to these and other interests and objectives, illustrated in Figure 1. Congress exercises control of the process at several stages, beginning with initiation (Congress must request a feasibility study), and including three to four separate congressional acts of authorization and appropriation of funds. The district office (in which a navigational project is located) of the U.S. Army Corps of Engineers examines several engineering options, as well as their costs and benefits, and prepares reports, including environmental impact statements, for various levels of internal and external approval. Public hearings are convened, and the review or concurrence (or both) of the affected organizations, on its of government, and other federal agencies is sought. Progress to step 16, congressional authorization, takes about 6 years (and each year's activities depend on congressional appropriations), after which several years may elapse before the funds for advance engineering and design are appropriated. The median time to complete the process was 15.2 years in the mid-1970s. This was for 36 projects that were completed (many were not) and for which the initial survey reports were submitted in the late l9SOs and early 1960s (Heiberg, 1981~. The complexity of the process and the number of decision makers have since increased. It is estimated (no major Improvements to navigational channels have been approved since 1976) that the process would take 20 years to 25 years to complete today. The Corps recently proposed accelerating the pace of this process (but without reform or abbreviation, which requires congressional action) by assembling "fast-track teams" that would conduct concurrent studies and reviews , and (subject to congressional approval) by dropping work on projects that have not been recommended for further development (or have languished many years) and concentrating on those that have been recommended for pursual (U.S. Army Corps of Engineers, 1982a ~ . The proposal aims to reduce the time spent by the Corps in completing required studies and reviews from 12 years to 7 years. While it is possible for ports or private interests to undertake navigational projects that will be funded by sources other than the federal government, a permit is required from the district engineer of the Corps, who coordinates responses to the application from other agencies and affected groups. A period of public notice and comment is required. An environmental impact statement is also required, as well as a public hearing. Memoranda of understanding between the Corps and five other federal agencies state that decisions will be made on these applications within 90 days of the public notice. The Corps has also initiated a "pull" in place of "push" system for

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2-3 Figure 1 Planning, approval, ~ut,~oxization, and funding process for for n.vigationa1 projects. 1 2 3 4 Congress Congxes. ~pps-~1.tes Following appropriation of funds, District Engineer authorizes fund. District Engineer conduct" o Investigates .11 altern.ti~. Saudi initial public meting to revie. o Perform 11~1ted drag t plan of aim, his Patti-. - technical fossil 11ty studies opportunity to identify and discuss - en~lro~ntal asses~nte ~1 palm ~ ~-r~i~ ~ o _ ~ ~~. ~1 =~ ~i~1 _c elf_ ~ ~1~ ~i~ and envi ro~nta1 qu. 1 i ty Survey Investig~t10n. s 6 7 B o ~~l~i~ Dimes ~~ me =~- ~~ ~1- ~t~, aim, 1~ Stage public o lnvestig.te. to~ul"~'on Tentative plan pro-ted groups, public resend co meting to stage alternative" and discussed draft EIS and draft F. discuss ~~t o Peafowl detailed feasible - teeb~ical feasibil Sty studies alter~tl~es - ~vi~ntal aunts o Select. plan for proposal in hi 1- ~ibi lip 0 =~ ~~ Hi (ma ~ ~ ( 15 has prior to late state publ lc "eeti ng 0 N~ mat 10 11 12 o Reviews consents o Reviews o Considers Vie.e of o Aevie.e B~ ad rearm ~ ~ ~ ~ ~ - ~ ~ ~ _ o Prepares r~n~ - Film F. as arm: isle - States o Distributes for ~tel~ remix - Fang EIS - f inal EIS - agencies o Files f inal EIS with EP^ - F1na1 FA o Issues public notice o Reviews and provides o Circulates to public for 30-day requesting public views recommendations review period and to be sent to Ward of - Final E1S governors, federal d_rt.ents - ~1 Har~r. (BE-) o Tr~nesits to chief of o Forwards reco_ndat ions engineers to Bum Ida ~ ~ I] 14 15 16 ~~ ~ _ ~ ~ ~ ~ _ o Reviews received o Foz.~:ds remend o Revue." o Congress holds hearings co_nte to Secretary of the away o Coordinates with me O Congress include. in Water o M-~1 lea ~t fog considex~tion o Pre-re~ his rec~nd.tion. Resource. ~velo~ent act as appropriate - Final Report o Forbids final FR, final EIS. air other legislation o Prepare. record - final E1S o ED co Congress (6 ho. ~ o President signs of decision { ~D) - ~ -vie. 17 18 19 Project ^uthorizat10n abut ~~- ~1 impel" ~ o Reviews Corps budget o Congress includes in guarantee to fulfill o Fo[.ulates pre-construct10n o Su-it. to Congress ^~propri~t Ions act obl ignitions xequi led by 1~. planning genera1 design 0 Pxesident Signs f e.g., real estate, cost ~~r~nd. [C-) aim, I, - _t~ EM ~ mire ~ Am, u~ ~- Ha. ~ aim, him necessary -ter Quality certif icates - Issues peal ic Entice and condoms .: least one p-1 ic Meting (36 an.) o ~~ ~~ ~1 (24 an.) 0 Initiates and complete. ~nstr~ien (60 go. e ~~ _ Hi_ ^~xt~ng Funds gate: AE6D to Construction Funding Construction ~]~ ~1 by Congress

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2-4 , . . ~ internal decision making to allow as many decisions as possible to be made at lower levels, where local knowledge has been accumulated and more timely decisions can be made, and to allow higher levels of the Corps to "pull" up for consideration only the decisions that must be made at that level. These recent changes are only now being exercised. AS few major deepening projects have been undertaken in the United States since World War II, and only one planned for nonfederal funding,* the principal criteria used in this country to determine the depths of navigational channels are those of the U.S. Army Corps of Engineers. The criteria consist of guidelines published by the Corps for the use of district offices, and the practices of the districts established by research or experience. A brief summery is given in the succeeding section. Criteria Used in the United States to Determine Channel Depth The Engineer Regulation "Deep Draft Navigation Project Design" (U.S. Army Corps of Engineers, 1981b) states for determining the depths of channels: The channel depth must be adequate for the design vessel draft, squat, trim, sinkage due to fresh water conditions, location of salt water intakes on ship, wave action and appropriate under keel clearance. Minimum under keel clearance should be two feet for soft channel bottoms and three feet for hard channel bottoms. Squat is calculated for expected vessel speeds and passing conditions for two way traffic channels. Salt water intakes on vessels must be five feet or more above soft channel bottoms. This clearance is needed to prevent silt from being pulled into the vessel condenser. Additional channel depth may be provided by advanced maintenance dredging based on the economics of dredging intervals and the need to ensure appropriate under keel clearance between dredging periods. The references cited are the Engineer Manual, Tidal Hydraulics, published in 196S, Devaluation of Present State of Knowledge of Factors Affecting Tidal Hydraulics and Related Phenomena," also published in 1965, and "Effects of Depth on Dredging Frequency," published in 1978 (U.S. Army Corps of Engineers, 1965a,b; Trawle and Boyd, 1978). Turning to the cited Engineer Manual,** two sets of criteria are specified for determining channel depth: one for navigation, another for ease of maintenance. These are briefly summarized here. The factors considered by the panel in evaluating them are addressed in detail in succeeding sections. *Galveston, Texas **Pertinent sections are reproduced in Appendix B

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2 -s Navi gation For Nazi gation, channel depth is generally considered to be determined "by the in-motion draft of the design vessel, the density of water, wave characteristics, the tidal characteristics, the characteristics of the bottom, and the economics of greater depth as a factor to reducing power requirements for the propulsion of the design vessel.'' Data for most of these factors are sparse and uncertain. The Engineer Manual recommends site-specific data gathering and - consultation with ship owners and local pilots but acknowledges that for calculation of such factors as squat, for example, "dependence will have to be placed on estimates." The references cited for calculations and considerations in estimating squat and other important characteristics of the design ship are at least 20 years old, some more than 30. These have not been updated. The rules of thump given by the Engineer Manual for underkeel clearance are draft + squat (3 ft) + rolling and pitching allowance (estimate) + clearance (2 ft or 3 ft). While the criteria for underkeel clearance have not been updated, it is interesting to note that the more recent Engineer Regulation now requires consultations with pilots and the concurrence of the U.S. Coast Guard in channel dimensions and other aspects pertinent to the safe use of the proposed channel, both in the preliminary and in the final design stages. The Engineer Regulation also calls for site-specific evaluation of physical environmental factors, including gathering of baseline data and model studies, and recommends the use of "[plertinent textbooks, research reports, or expertise from other agencies." The choice of the design shipts), as pointed out in the Engineer Manual, is a crucial one, and this is clarified by the Engineer Regulation as "selected from comprehensive planning studies of the various types and sizes of vessels expected to transit the channel...over the economic life of the project...." Usually the largest vessel of the major commodity movers, it "is selected by evaluating tradeoffs of delay cost incurred by larger vessels and cost of increased channel dimensions. The maximum size vessel and least maneuverable vessel in the fleet must be able to make a safe transit [taking into account special conditions that may be imposed--for example, speed limits' use of high tides for additional water depth, one-way traffic, tug assistance!." There are regulatory and institutional concerns beyond those of the U.S. Army Corps of Engineers: those of port authorities and the U.S. Coast Guard, for example, about the consequences of groundings. These may result in the "special conditions that may be imposed." While many vessels can strike a soft channel bottom or ground without harm, all groundings must be reported to the U.S. Coast Guard under the Port and Waterways Safety Act of 1972, and a fine may De levied against the master or pilot. Maintenance The Corps has expended considerable ef fort investigating, modeling, and adding to the understand' ng of the hydrology of channels,

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20 estuaries, and rivers. This understanding is essential to several missions of the Corps--for example, engineering design and construction of flood control and water-resources projects--and to the interactions of these works with navigational channels. One updated reference in the Engineer Regulation is Trawle and Boyd (1978) and, by parity of reason, Trawle (1981b). Trawle and Boyd (1978) is the first and Trawle (1981b) the second report in the series , _ Effects of Depth on Dredging Frequency. The first report discusses : the evidence from questionnaire surveys of Corps districts respecting overdredged depths (or "overdepth dredgings. Overdredged depths are of two types (see Figure 2~: One is the "allowable pay overdepth," an additional depth for which the Corps agrees to pay the dredger to ensure that the design depth is achieved--that is, allowing for the inaccuracies of dredging and surveying. The other is "advance maintenance overdepth" or "purposive overdepth" for (1) maintaining project depth in rapidly shoaling areas, (2) reducing the frequency or maintenance dredging, or (3) allowing more efficient dredging operations, if deeper cuts are more cost-effective, or for some combination of these reasons. The surveys indicated that in all coastal districts the allowable pay overdepth varies from 0 ft to 3 ft (0.9 m}, most clustering at 2 ft (0.6 m), for channels from 30 ft to 47 ft (9.1 m to 14.2 m) deep. This "plus 2 ft" seems to be a rule of thumb that has evolved. The surveys also revealed that past shoaling history seems to be the main determinant of advance maintenance dredging in the coastal districts (amounts varied from 1 ft to 8 ft (0.3 m to 2 e4 m) nut are 3 ft (0.9 m) or less in 84 percent of the projects) and that the method of assessing past shoaling varied from district to district. Specifically, Trawle (1981b) indicates that three techniques and formulas were being used to determine whether and where advance maintenance dredging was needed, all less than adequate, and that hydrographic surveys were generally infrequent (Table 3~. The second report offers a formula for calculating shoaling rates as a function of the volumes dredged in the past (from annual records of dredging work) to maintain project depth in segments of a channel, and correcting with hydrographic surveys. One object of this technique and formula is more efficient scheduling of maintenance dredging, another is to encourage variable advance maintenance dredging (that is, by channel segment} for fast-shoaling areas. An implicit objective of the report seems to be to bring these practices into conformity with an adequate standard and encourage more frequent hydrographic surveys. Implications The glacial pace of the multistage process for approvals, congressional authorization, and other steps to be completed, and the number of years over which the process itself has evolved, have several Implications for channel design. First, the validity of original assumptions and estimates attenuates with time, necessitating update studies and reexamination of needs, costs, and benefits. The

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2-7 Figure 2 Two types of overdredged depths in navigational channels:* (a) typical dredged channel, showing allowable pay overdepth; (b) dredged channel with allowable pay overdepth and advance maintenance dredg~ng overdepth WAJER SURfACE _ ~ ~ _ nT11~4 ~_ DEP~ ~ AU - ORJZED OR RE~ R") _ _ '/~/~N (a) (b) , , SLOPE _ALLOWABLE PAY OVERDEPnt (USUALLY ~ OR 2 F~ I ~ r ~ WATER 9~1RfACE ~ `sorrou WID7H (AU"IOPIZED OR RE - IRED) - _ DREDGD DEP TH ~___ _ _ DEPTH tAUTHORtZED OR REOUIREa '- _ p777~ SLOPE _/1 _ , _ ~OT~ ~ID"I (4JJ - OI.ZCD 0R R~ 40V - CE ~~NT - - CE (OVERDEP - ) p_ALLOW - LE PAY OVERDEP~ *SOURCE: M. J. Trawle and J. A. Boyd, Jr. (1978), Effects of Depth on Dredging Frequency, Report 1, Survey of District Offices, Technical Report H-78-5 (Vicksburg, Miss.: U.S. Army Engineer Waterways ExperLment Station), May 1978, p. 6.

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2 - 9 deepening of the major channel serving Tampa Bay, for example, was authorized in 1970. The final environmental impact statement was submitted in 1971, an updated statement was filed in 1975, the draft of a supplement in 1976, and the final supplement in 1977. The original estimated cost to deepen channel segments was $97.5 ~ [lion. In 1981, the estimated cost was $178 million and this included reductions of more than $12 million owing to favorable bids, to work completed under bid, and to the savings represented in dredging to depths a foot less than those authorized (U.S. Army Corps of Engineers, 1982b). While much may still remain valid from earlier studies, the time scale of the decision making process is far longer than the time scale of major changes in the world shipping fleet. Less than 5 percent of the ships in the world's merchant fleet are 25 years old or more: more than 59 percent are under 10 years old (Lloyd's, 1980~. The design ship used to specify channel improvements may pass from drawing board to desuetude before channel improvements receive final approval and work begins. Second, the nature of this process (and the time needed to complete it) discourages innovation. Approximately 1 percent of the total budget of the U.S. Army Corps of Engineers is for research, and this must be divided among several subjects of equally preening importance to the missions of the Corps. As described in succeeding sections, the number and complexity of the factors that need to be understood to determine the depths (and other dimensions) of navigational channels demand considerable research. Some of this may be undertaken by the districts on passage of the legislation authorizing a navigational project--for example, model and simulation testing of the channel design for various vessels and unique features of the local environment--as their budgets allow. Model tests, simulations, and intensive local data collection are generally expensive. In their absence, design depth is usually based on empirical rules ("rules of thumb") set out in Corps publications, with additional depth ts) for achieving the design depth and advance maintenance dredging. Furthermore, the design and engineering undertaken after authorization are bound by the terms of the authorizing act. Even in areas of a particular project's design and engineering that may allow some latitude, the nature of the decision making process and the number of decision makers involved ensure that changes will be addressed conservatively, and in terms that are readily understood or familiar. These considerations, together with the very long tome needed to plan and secure approval of navigational projects, tend to fossilize the rules of thumb for channel depth.

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