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This report describes, defines and interrelates a series of capability requirements for the design of bottom mounted surface structure and suspended cable structure types of Fixed Ocean Facilities. The capability requirements are categorized and their interrelationship defined by a generic breakdown structure. Keywords: Ocean engineering.

This report assesses the environmental effects of maintenance dredging in Mississippi Sound in 1974. Background conditions were measured before and after dredging, and extensive monitoring was conducted during the dredging operation. It was found that dredging had no significant or lasting effect on any of the conditions evaluated in this investigation. TUrbidities ans suspended solids were measured and the size and dispersion of the discharge plume were defined. Distributions and levels of bacteria and heavy metals were studied to measure their release from the sediments to the waters. The biological parameters investigated were: plankton, coliform bacteria, and benthic invertebrates. The discharge plumes of suspended solids were small; the solids settled rapidly, and, within 2-3 hours after discharge, no plume was detectable.

The report describes an investigation concerning parametric sonar applications to under-ice operations. Two basic tasks are undertaken. These are first, a data gathering program in an environment which partially simualtes the under-ice environment; and second, a theoretical investigation which extrapolates the results obtained to the under-ice environment. To gather data in a representative environment, a parametric sonar operating in a sub-bottom profiling mode was used in a downward looking mode analogous to upward scanning of the water to sea-ice interface. Results were analyzed and compared to possible under-ice operations in the theoretical investigations.

The study was conducted to determine the effects of water temperature on the results from a movable-bed model study of Masonboro Inlet, N.C., with a secondary objective to determine the effects of experimental procedures on the model results. The erratic reproduction of short-period waves near the beach and inlet was found to be the most probable source of experimental error. Other experimental errors discussed include the influence of initial molding of the movable bed, method of simulation of littoral transport approaching the inlet test sections, and bed sounding procedure. The study did not define temperature effects on movable-bed results; however, no evidence was found to indicate that temperature adversely affected the results of the Masonboro Inlet model tests within the range of temperatures investigated (50 to 78 F). A general course of action to resolve the question of temperature effects is recommended. The study consisted of three pairs of tests. Two pairs of tests were conducted with different water temperatures; the third (or control) pair was conducted with the same water temperature. Appendices provide: (1) Results of the hydrographic surveys; (2) Scour and fill maps; and Beach profiles for each test.

The proposed plan for improvement (Scheme 1) provides for channel enlargement of Turkey Creek from the Pocotaligo River upstream to station 240+00 and for the implementation of flood plain management measures by the local community. The improved channel will have a length of 4.5 miles with bottom width varying from 60 feet at the outlet to 18 feet at station 240+00. Required right-of-way will vary from 200 feet in the lower reach to 100 feet in the upper reach. Culverts and bridges will be modified or reconstructed to provide sufficient capacity for proper functioning of the designed channel. This report contains maps, profiles, and cross sections which indicate the extent of flooding that has been experienced and that which might occur in the future along Turkey Creek. From the maps, profiles, and cross sections, the depth of probable flooding at any location, by occurrence of the Intermediate Regional or Standard Project Flood may be learned. With this information, flood levels for buildings may be planned high enough to avoid flood damage, or other measures taken to minimize flood hazards., Original contains color plates: All DTIC reproductions will be in black and white.

Contents: Ocean Engineering Topics and Policies; A Forecast of Ocean Engineering Trends; U.S. Navy's Deep Ocean Engineering Program; NAVFAC Role in Ocean Engineering; Role of the Engineering Field Division and Naval Construction Forces in Ocean Engineering; NAVFAC Role in Undersea Nuclear Power; Undersea Nuclear Power; The Seabees Role in Ocean Engineering; Deep Ocean Engineering; Design Parameters; Ocean Floor Concrete Habitats; Power Supply, Distribution, and Underwater Lighting; Undersea Nuclear Power; Equipment in the Ocean Environment; Subsurface Profiling Instruments; Design of Deep Ocean Simulation Facilities; Concrete Internal Pressure Vessels; Development of Plans and Specifications for an Ocean Simulation Facility; Nonmetallic Materials - Plastics; Development of High-Strength Steels for Ocean Engineering Applications; Corrosion and its Prevention; Bottom Soils and Foundations; NCEL Research on Bottom Soils and Foundations; Anchoring and Mooring; Diving Equipment; Reliability and Safety of Deep Ocean Engineering Systems and Related Equipment.

Preliminary laboratory analyses are presented of underway bottom samples and core samples from the southern approach channel to the Chesapeake Bay. The sediment investigation included a size analysis, megascopic logging of the cores, pH measurements, organic analysis, and textural analysis of the sands. The shell accumulation below the sediment is explained by a traction-zone mechanism.

This study of the Delaware River dredging spoil disposal problems was undertaken by the U.S. Army Corps of Engineers, Philadelphia District. Part III, sub-study 2 of this study reports the results of the overall investigation on the nature of the shoals in the navigation channel and the anchorages, on their immediate and ultimate sources and the causes of the deposition of the materials in certain reaches of the navigation channel and in the anchorages. The hydraulic data presented reports freshwater inflows, tidal and salinity regimen plus sediment transport in the Delaware Estuary. An in-depth study is taken on the shoaling off Marcus Hook, PA., Original contains color plates: All DTIC and NTIS reproductions will be in black and white. See also Part 3, Substudy 2, Appendix A, ADA084364.

Three cruises were made to the Kennebec estuary in Maine to study the tubulent variations of velocity and temperature of the river. An instrument was devised for measuring the fluctuations in horizontal velocity and inclination of flow. The device operated by rectifying, smoothing, and recording (Speedowax) the pulsed voltage from an induction-coil-type propeller meter. The inclination of the flow to the vertical was measured with a vane rotating on a horizontal axis ahead of its leading edge; the vane was connected to a potentiometer. The instruments were either suspended in the river on a flexible cable or from a fixed vertical mast, or they were fixed to a tripod resting on the bottom of the river. Suspension from a flexible cable was generally used; in calm weather, no perceptible difference was noted in the records from the 3 suspension methods. No temperature fluctuations were present. The data indicated mean mixing constants of 0.67 and 1.9. The mixing and stability of an estuary are suggested to be somewhat linear; only a small part of the turbulence appears to transport the momentum and heat. High stresses were noted near the surface; further study of the surface and composite layers with several meters at different depths is recommended.

Wind and sea-state data are tabulated from USCG weather logs for the Brenton Reed Lightship and the Beavertail Point Lighthouse Station. To supplement this data, wave height and frequency data were measured by pressure changes a t the sea bottom from the Brenton Reed Lightship. The general procedure comprised dropping the hydrophone over the side to the bottom while leaving 15 to 20 ft of slack cable. The pressure variations were recorded for 20-min periods. The runs included 15-min sections with the hydrophone hanging 80 ft below the lightship (about 10 ft off the bottom). The quantitative rule of these measurements was limited by the variation in the response of the ship. Regular wind and sea-condition estimates were made at 4-hr intervals aboard the lightship. A correlation of pressure and weather data indicated that sudden winds often result in high sea estimates whichare not observed at the bottom. As a typical storm came up, the bottom pressure variations lagged behind the surface estimates until the swell built up. These variations then continued long after the surface estimates indicated a decrease in wave action. A nummerical relationship between observed surface conditions and bottoms pressure variations was not possible because of weaknesses in the surface sea observations and the lack of suffiicient data.

Twenty successful bottom photographs were taken in the lower Chesapeake Bay and adjacent shelf area. These are included in the report along with the Sacchi disc reading, depth measurements, description of the photograph, and information form the core taken nearest the location of photograph. None of the photographs show any evidence of plant life on the bottom. One fish, one worm, one star fish, a track, and numerous shells and shell fragments are the only clear evidence of animal life. The bottom appears to be monotonously flat with only a few photographs showing ripple marks or slight undulation of the bottom. The inorganic bottom material appears to be of sand size or smaller. Six of the photographs are reproduced in stereoptic form.

A statistical study was made of the accuracy that can be expected in hydrographic survey work where comparability of successive surveys is important. Tests were made at Mission Beach, Calif., to determine the magnitude of sounding and spacing errors. Sounding errors result from errors inherent in the sounder and the methods involved in reducing sounder data to an actual bottom profile; to determine such errors, soundings were taken of a single profile 8 times successively in a 5-hr period. Echo-sounder data and leadline soundings were analyzed separately. For any one profile obtained by the echo sounder, an uncompensated error averaging 0.07 ft was indicated. With the leadline, a comparison of profile deviation against the average profile showed an uncompensated probable error of 0.11 ft; comparison of successive profiles showed an error of 0.20 ft. A survey of more than 1 profile indicated that the surveying errors may be significant if toc few profile lines are used. Spacing errors result because a particular profile may not represent entirely its assigned section of beach. To determine spacing error, data were taken from soundings of sections of (1) 11 ranges spaced 200 ft apart at 1-wk intervals and (2) 47 ranges spaced 200 ft apart at 3-mo intervals. The portions of the probable error curves for spacings between 10,000-ft-long beach) an error of 40, 000 cu yd can be expected in cubage computations; for a spacing of 1000 ft, an error of 114,000 yd can be expected.

A study was made of the possible causes for decline of oyster production and of means for restoring productivity. Water samples were taken at numerous stations (designated by the latitude and longitude to the nearest 0.1 min) with a Forest bottle of 1-1 capacity. Top and bottom samples were taken when depth was greater than 2.5 ft. The analyses induced determinations of surface temperature, salinity, and dissolved oxygen content. The degree of turbidity was obtained by measuring the extent of transmission (at lambda of 425, 525, and 650 mmicrons), with a Fisher filter photometer, through a 5-cm cell containing the sample. Wave heights, meteorological data, and current observations were also made.

This study of the Delaware River dredging spoil disposal problems was undertaken by the U.S. Army Corps of Engineers, Philadelphia District. Part I of this study focuses on the description of the Delaware River in regards to amount of water-borne commerce traveling over the river, problems associated with the port of Philadelphia and the necessary channel dimensions required for future water-borne transportation. A brief history of past dredging operations plus plans for private and federal development are described. Appendix A of this document by C.F. Wicker focuses on the study of shoaling in the Delaware Estuary and its hydraulics including tidal data, salinity intrusion data and annual shoaling rates at several sediment stations. (Author), See also Part 2, Substudy 1, AD-A070 624.

This study of the Delaware River dredging spoil disposal problems was undertaken by the U.S. Army Corps of Engineers, Philadelphia District. Part III, sub-study 2, Appendix A is subtitled 'Source and nature of shoaling materials in the Delaware Estuary'. This phase of the investigation was undertaken to determine the total composition of the shoal utilizing techniques capable of determining all phases including its amorphous and organic materials as well as, crystalline materials and to compare this with the composition of bottom and suspended sediments from streams draining watershed areas as well as bottom sediments of the bay. Environmental parameters were also evaluated in the water column to estimate the sediments resulting from pollution and eutrophication of the estuary by industry and municipalities. Special tests were conducted to determine the physiochemical and electrophoretic mobility parameters associated with flocculation occurring at Marcus Hook shoal. (Author), Original contains color plates: All DTIC and NTIS reproductions will be in black and white. See also Part 4, Substudy 3, AD-A070 625.

The Inshore Survey Project in the Boston Harbor area was pursued further during the quarter. The present report includes progress notes on the following topics: Bottom Sediments; Bottom Photography; Magnetic Anomalies; Wave Measurements, and Properties of the Water.

A theory is presented which enables the computation to be made of 200- to 5000-cps bottom reverberation returning from very great ranges in shallow-water. Typical computed curves are presented for reverberation level vs range/water-depth. Computed curves are presented for scattering strength vs range/water-depth. These later curves are presented for both the isospeed and negative sound-speed gradient cases. (Author)

The decrease of air-blast peak pressure with distance along the water surface was studied for shallow underwater explosions. Peak pressures were obtained from shock-front velocity measurements by using the Rankine-Hugoniot equation. The shock-front velocity and sound velocity were determined from measurements taken directly from the film record. The slopes of the pressure- distance curves for the region observed (45 to 200 charge radii) were lower than those from a charge in the air. The crossover observed for some of the shallow shots was believed to be real. No indication was obtained that the proximity of the river bottom affected the magnitude of the peak pressure along the water surface. Curves for the peak pressure as a function of reduced charge depth showed that the pressures along the water surface scaled with the cube root of the charge weight between 20 and 4200 lbs.

An experimental investigation was made on the Langley tank no. 2 monorail to determine the effect of shallow water on the hydrodynamic characteristics of a flat-bottom planing surface. Measurements were taken of lift, drag, and trimming moment at a constant speed over a range of trims, wetted lengths, and clearances between the model and a false bottom in the tank. The values of lift, drag, and trimming moment about the trailing edge of the model all increased with decreasing clearance. The most apparent increases occurred as clearance decreased below 2.5 inches (1 beam). With combinations of high wetted length and high trim, however, the values began to increase at somewhat greater clearances. The lift-drag ratio increased with decreasing clearance for wetted lengths greater than 0.8 beam and trims less than 16 deg. The roach in the wake of the model increased in height and moved farther aft of the model as the clearance decreased. A description of the monorail and its associated apparatus is included in an appendix.

An investigation was made at a Mach number of 0.13 in the Langley stability tunnel in order to determine the effects of closed wing-root air ducts (horizontal) on the static longitudinal and static lateral stability characteristics of unswept-midwing models having wings of aspect ratio 2, 4, and 6. In addition, the effects of top and bottom fuselage ducts (vertical) on the static longitudinal and static lateral stability characteristics of model configurations employing the unswept wing of aspect ratio 2 were determined. The results of the investigation have indicated that, in the low angle-of-attack range, the addition of and increase in size of the horizontal ducts on model configurations employing an unswept wing of aspect ratio 2 resulted in a large forward movement of the aerodynamic center regardless of the vertical location of the horizontal tail. When the aspect ratio of the wing was increased from 2 to 6, this effect became more pronounced. In contrast to this effect of the horizontal ducts, the addition of and increase in size of vertical ducts on model configurations employing the wing of aspect ratio 2 produced a slight rearward movement of the aerodynamic center. Regardless of the aspect ratio of the wing, the addition of and increase in size of the horizontal ducts caused an increase in directional stability for complete models or a decrease in instability for tail-off configurations at low and moderate angles of attack. The addition of and increase in size of vertical ducts on the models with the wing of aspect ratio 2, however, resulted in large decreases in directional stability which were about constant for the angle-of-attack range investigated.

The plan of improvement for the Buck Creek watershed consists of enlargement and realignment of the existing channels on Buck Creek and its principal tributaries which will provide varying degrees of protection within the watershed. The enlarged channels will contain the 5-year frequency storm at the mouth of Buck Creek with the degree of protection gradually diminishing going upstream to the point that the 3-year frequency storm will be contained in the upper watershed. The total length of channel improvements on Buck Creek and its tributaries is 18.94 miles with 11.36 miles on Buck Creek, 2.89 miles on Deep Branch, 2.98 miles on Camp Swamp, and 1.71 miles on Hawkins Branch. Channel bottom widths vary from 10 feet to 35 feet with 1 to 1 side slopes.

The Detailed Project Report was completed on 31 March 1965 and found the project to be economically feasible. The recommended plan is shown on the attached Plate 1. The plan of improvement calls for enlargement and realinement of the existing channels on Buck Creek and its principal tributaries which will provide varying degrees of protection within the watershed. The total length of channel improvements on Buck Creek and its tributaries is 18.94 miles, with 11.36 miles on Buck Creek, 2.89 miles on Deep Branch, 2.98 miles on Camp Swamp, and 1.71 miles on Hawkins Branch. Channel bottom widths vary from 10 feet to 35 feet with 1 to 1 side slopes.

It was found that the flood and drainage problem in Gapway Swamp watershed is typical of that generally found in the coastal regions where the streams have low banks and flat gradients. There are substantial agricultural losses from floods and prolonger rainy periods which cause complete or partial destruction of crops, reduction in yield and reduction in quality compared with similar crops produced on higher lands. The recurrent floods have caused considerable damage to crops, pasture, and woodlands. The most damaging floods are those which occur during the growing season beginning in March and extending through September. Local interests have installed laterals and on-farm drainage facilities that are ineffective during prolonged rains and storms because of the blocked outlet channels. A study of the watershed indicates that the most suitable method to effect flood reduction and drainage is by means of channel improvement along the main outlets. The plan of improvement for the Gapway Swamp watershed consists of enlarement and realignment of the existing main stem channel. The enlarged channel wil contain the 5-year frequency flood. The total length of channel improvements on Gapway Swamp is 14 miles. Channel bottom widths vary from 60 feet to 32 feet with 1 to 1 and 2 to 1 side slopes. Other channel data are contained in tables shown on Plate 4, Appendix A.

This report present new information concerning the local layers of rock likely to be encountered in subsurface investigations, and the physical nature of sediments such as sand or mud presently being deposited in the Georgetown Harbor area, as indicated by drilling, seismic profiling and bottom sampling.

Clay composition and heavy-mineral analysis of more than 100 sediment samples within the physiographic unit comprising Charleston Harbor watershed reveal mineral ratios which are diagnostic to the source area. Ratios of hornblende and kaolinite indicate a Piedmont source sedimentr superimposed on typical residual Coastal Plain sediment in the shoal areas of Charleston Harbor; such overlap began in February 1942 when the Santee watershed was diverted to Charleston Harbor via the Cooper River. Sediment movement, as suspended load, from the source area to deposition site, is delineated by the clay-mineral ratio while bed load movement is reflected in sand-size hornblend ratios and sedimentary parameters. Movement of sediment to the shoal areas in Charleston Harbor is perdominately from the upland source via Cooper River and lesser amouints through the tidal inlet. Factors regulating locaton of shoaling areas in Charleston Harbor include (1) hydrologic cycle control of sediment supply from the watershed, (2) density currents of the partly mixed estuary effecting longer duration of bottom flood flow than the bottom ebb flow, (3) Coriolis force effect on net tidal propagation, and (4) induced low energy zones at junctions of rivers.

Improved drainage is needed over a large part of the watershed, The flat topography pockets water and the solid become waterlogged creating acute problems to the urban developments. The present Sawmill Branch channel is not deep enough to provide adequate internal drainage. Flood water from the tributaries backs up existing drainage ditches reducing their efficiency. The proposed plan of improvement provides for channel enlargement from the outlet end at the Ashley River to Highway 17A. The enlarged channel will have a total length of approximately 9.7 miles with bottom widths varying from 60 feet to 18 feet. A cleared right-of-way will be required varying from 120 feet in the lower reach to 60 feet in the upper reach. Culverts and bridges will be modified or reconstructed to provide sufficient capacity for proper functioning of the designed channel.

Report on Missouri River Design Study.

Original contains color plates: All DTIC and NTIS reproductions will be in black and white.

The pressure distribution produced by a hydrofoil of high aspect ratio at the bottom of a shallow basin of constant depth is computed. The different character of the solution in the 2 cases of subcritical and supercritical speed is discussed. In the subcritical case, the pressure distribution is approximately sinusoidal, whereas it decreases exponentially with the distance from the foil in the case of supercritical speed. The effect of a hydrofoil upon mines of the pressure-sensitive type is considered. For ordinary operating conditions of a hydrofoil craft, it appears that the duration and amplitude of the pressure signature are of similar orders of magnitude as those of ordinry sea waves. In this case, therefore, the signature of the craft is of a type with respect to which mines are insensitive. However, if a hydrofoil craft is operated close to critical speed, it is possible to produce signatures of longer duration, approaching those resulting from ordinary vessels. A numerical example is calculated and some of the difficulties arising in employing hydrofoils as a mine-sweeping device are pointed out. In general, the discussion is restricted to the case of a single hydrofoil. The case of 2 or more foils, however, can be obtained by superposition of the results derived for a single foil. Equations are given which permit calculation of the load applied by a ship model to false bottoms in towing tank tests.

Plots of apparent crater depth vs charge weight showed that under water charge position has a moderate effect on crater depth for a sand bottom, particularly for the 100-ft scaled water depth. Charges below the bottom produced crater widths averaging 1.15 the width of comparable craters of charges positioned at the bottom for both 60- and 100-ft depths. Significant crater lips were formed in eac scaled water depth for charges below below and at the bottom. For loess bottoms, plots of the crater depth vs charge height indicated a marked effect of the charge position on crater depth. Crater depths for charges positioned at a scaled depth of 90 ft below the bottom were about 1.3 the depths of comparable craters for bottom-positioned charges. Below-bottom charges produced crater widths about 1.15 greater than those from bottom-positioned charges. Significant crater lips were formed in each scaled depth for both charges in the 20 KT range detonated 60 to 100 ft below the water surface would cause little air-blast damage beyond a 3500-ft radius. Damage radii also appeared to be reduced by deeper detonations. The proximity of the bottom in a 100-ft depth blast had no apparent effect on air-blast pressures.

The cruises were made in order to obtain a 3-dimensional picture of the distribution of various physical oceanographic parameters of Narragansett Bay and its approaches in the summer of 1952. The surface temperature in the approaches increased from the edges of the offshore region to the center. The surface salinity increased from Narragansett Bay, Block Island Sound, and Buzzards Bay to the southeast of the offshore area. The surface was about 19 deg F warmer and about 0.50 deg/oo less saline than the bottom. The central portions of the Bay itself were consistently warmer although no consistent surface temperature gradient was noted in either passage at either stage of the tide. In both passages, surface salinity increased toward the mouth of the Bay at both stages of the tide. On the surface, East Passage was 2 deg to 3 deg F colder than West Passage at both stages of the tide. The temperature on the bottom of the 2 passages at slack before flood was about the same; at slack before ebb, East Passage was about 10 deg F cooler than West Passage. The surface of East Passage was 2 deg F and 11 deg F warmer than the bottom at slack before flood and slack before ebb, respectively; in West Passage, the surface was 4 deg F warmer at both tidal stages. East Passage surface and bottom salinities were about 0.50 deg/oo and 0.80 deg/oo more saline at slack before ebb than West Passage, the surface of which was about 0.10 deg/oo and 0.50 deg/oo less saline than the bottom at slack before flood and slack before ebb, respectively. The surface of East Passage was about 0.80 deg/oo less saline than the bottom.

A total of 33 hydrographic stations were occupied in March and April of 1951 during field observations in the area north of the 60th parallel and between Greenland and the Greenwich meridian. In January and February of 1952, 68 stations were occupied in the same area. At 44 m, the shallowest subsurface observation, the temperature was -0.47 deg C, the salinity 34.88 salinity, and the sigma-t (density) 28.05. The temperature below the 44-m level decreased and the salinity increased until bottom water conditions were attained at 1420 m. High surface salinity was in important factor in the surface density inversion and low surface temparature. Twenty-three stations showed unstable high densities; 15 showed surface densities equal to or exceeding the density of the deepest water observed at the station. Homogeneity was rarely found between the surface observation and the shallowest subsurface observation. The data substantiated each point of Nansen's theory of bottom water production except for the argument for the formation of a homogeneous water column during the process.

The examination of past and current ocean construction projects has revealed the need for platforms to perform a wide range of specific functions. In the delineation of these functions it has attempted to categorize them by the unique features of size and type of platform that could fulfill each function. This does not mean that a separate platform is required for each function but it serves to show common characteristics that can be combined in multi-function platforms. These functional categories are listed below and each will be discussed in detail in succeeding sections: Large structure implantment; Acoustic range servicing; Light structure implantment; Pipe laying and servicing; Cable laying and servicing; Fleet mooring installation; Equipment transport; Bottom survey and sampling; Bottom excavation and trenching; Acoustic bottom surveys; Towing, personnel transport, and support services; Equipment flotation.