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An existing comprehensive physical model that correctly reproduced tides, tidal currents, and density currents throughout the entire New York Harbor was used to determine the effects of constructing a current deflection dike at Norton Point, Coney Island, New York. The study included tests in the model to define the effects of the dike on tidal heights, current velocities, surface current patterns, salinities, and the distribution of dye from four sources throughout the New York Harbor complex. Based on results of the model tests, it was shown that the Norton Point dike would have the following effects in the study area: local current patterns would be changed and a continuous east-west current would be set up along the Coney Island beaches, tidal heights and tidal phasing as well as the salinity regime would not be affected significantly, sediment buildup behind the dike would occur in the period while the area is being filled by the littoral drift, and concentration of pollution from the Passaic Valley Outfall showed a slight net decrease at low-water slack along Coney Island, but a significant net increase at high-water slack.

Contents: Geologic Lineations in Dickey-Lincoln area; Surficial Geology and Drainage; Surficial Geology of Eastern Portion; Drainage of Eastern Portion; Boring Data Locations in Eastern Portion; Surficial Geology of Central Portion; Drainage of Central Portion; Surficial Geology of Western Portion; Drainage of Western Portion., See also Part 1, AD-A023 276.

The report presents a systematic set of guidelines for creating new marshes from dredged material under a variety of situations and constraints. New marshes are characterized on the basis of the frequency of dredging, confinement requirements and the need for surcharging. Pertinent information on important physical environmental factors, dredging and disposal operational practices, and engineering properties of dredged materials is used to develop guidelines for creating each type of marsh., Report on Dredged Material Research Program.

An analysis is made for steady free convection of groundwater about a hot dike trapped in an aquifer of infinite extent. Within the framework of boundary layer approximations, similarity solutions are obtained for a class of problems where wall temperature varies as xλ, i.e., a power function of distance from the origin where wall temperature begins to deviate from that of the surrounding groundwater. The uniform heat flux solution emerged as a special case with λ = 1/3. It is found that vertical velocity and the temperature profiles are of the same shape, and that the boundary layer thickness is proportional to the square root of the distance from the leading edge. Analytical expressions are obtained for boundary layer thickness, local and overall surface heat flux, as well as the local and average heat transfer coefficients. Some representative velocity and temperature profiles around a dike are also presented.

The need for the development of basic principles which can be used as a guide in the design of spur dikes or rock groins for the regulation and improvement of rivers, and a laboratory investigation of undertaken for this purpose are discussed. The investigation was designed to determine some of the factors which affect the performance of dikes as well as factors which should be considered in the design of dikes. Also discussed is a system for evaluating the performance of dikes and for correlating laboratory and field results., Presented at the ASCE Transportation Conference held in Philadelphia, Pa., on 17-21 Oct 66.

The Devil's Island Reach of the Mississippi River is located about 5 miles upstream of Cape Girardeau, Missouri, between miles 55.0 and 68.0. A movable-bed model with scale ratios of 1:400 horizontal and 1:100 vertical, reproducing approximately 13.0 miles of the Mississippi River, was used to develop a channel of project dimensions through the reach. Results of the investigation indicated that: Contracting the channel in this reach to a control width of 1500 ft should generally provide adequate channel depths and alignment, except that special treatments might be required in crossings depending on the channel alignment and degree of sinuosity provided in the improvement plan. The control width can be reduced to less than 1500 ft to improve the depth and alignment of the channel over crossings with dikes of lower elevation than those used for the 1500-ft contraction. The cost of dike construction can be reduced by use of the stepped-down principle in the design of dike systems. (Author)

Greers Ferry Dam, a concrete gravity structure with two earth dike sections, is located on the Little Red River in Central Arkansas. The Waterways Experiment Station (WES) was requested by the Little Rock District to review the design of Greers Ferry Dam from a soils and foundation standpoint. All data were furnished by the Little Rock District. In addition, a field inspection of the damsite was made by representatives of WES. The review has been completed and the comments presented herein concern those features of the geology, soil conditions, and stability computations which may have bearing on the stability of the dike sections of the dam.

Containment of the polluted dredge spoil will remove it as a source of pollution to the open waters of the bay. Dikes will protect Pointe Mouillee Wildlife shoreland marshes from further erosion and create additional fishing habitat. Future development and management of the site and marshlands will optimize wildlife habitats and provide recreational potential for waterfowlers and naturalists. Replacement of 700 acres of Lake Erie bottomland by the proposed structure may introduce an adverse esthetic impact on the natural landforms of the area. The dikes and management measures would create a secondary adverse impact on historical and biological relationships of the marsh to the lake. Although the structure will offer a protection against erosion from wave action, it will not prevent losses of vegetation from flooding. The function of the marsh as a spawning and feeding habitat for fish, as it existed in the 1930's, is now measurably reduced and would not resume behind the anticipated dikes. A lagoon situation behind the dikes, which would enhance conditions relative to spawning and feeding, is dependent on levels of turbidity and concentrations of pollutants that may result. Alternatives to the recommend plan include: (1) Resume open lake disposal which would return pollutants to the waterways, but such action is prohibited by request of the Governor of Michigan; (2) Discontinue dredging of polluted sediments which would reduce channel depths and curtail shipping; and (3) Use another site for disposal.

The purpose of Appendix E is to define the magnitude of the present and projected flood threat on the main stem rivers, major tributaries and coastal areas of the North Atlantic Region; to evaluate potential programs for flood damage reduction; and to describe various aspects of, and the potential for, water management to increase the supply of water for projected future withdrawal and instream water needs. The information and data developed serve as inputs to Appendix T, Plan Formulation., Appendix E to report dated Jun 72, AD-A036 616. See also Appendix F, AD-A036 627. Contains envelope with 2 maps.

This project was authorized by the River and Harbor Acts of 1927 and 1930, for the purpose of obtaining and maintaining a 9- by 300-ft channel for navigation from the confluence of the Missouri River (St. Louis, Mo.) to the confluence of the Ohio River (Cairo, Ill.). The main channel will be contracted to 1500 ft between riverward ends of dikes throughout the study area in order to maintain the 9-ft depth during periods of low flow. A comprehensive study of the historical geomorphology supplemented by physical models of the river and side channels was made to determine the physical impact of river contraction works on river morphology and behavior. An intensive study of the terrestrial flora and fauna was also conducted to inventory the existing organisms and communities located in the unprotected floodplain and to assess the impacts of operation and maintenance activities on the organisms and communities. In addition, the aquatic flora and fauna were studied to inventory the aquatic communities present in the study area and to assess the importance of side channels to the riverine ecosystem.

The research helps to determine the environmental response to the deposition to spoil on salt marshes using diked and undiked techniques. It considers the effects on water quality, motile and benthic biological communities and the marsh grass habitat. The emphasis of these studies has been on the identification of the processes responsible for observed effects and the assessment of ways of minimizing there. The ultimate goals in these studies has been to develop an approach to predicting environmental responses due to dredging activities. All of the studies described in this report were carried out in the salt marsh estuarine environment of the Southeastern Atlantic Coast. In every case studied, hydraulic pipeline dredging was the technique used. The disposal of the dredge material was carried out in confined or unconfined salt marsh areas., See also report dated Mar 73, AD-763 920.

Objectionable conditions associated with confined disposal of dredged material were studied through on-site investigations of four U.S. Army Engineer Districts, and discussions with Corps personnel in ten other districts. Three general conclusions were reached: (1) Techniques are available for the prevention of some objectionable conditions associated with the effectiveness of confined disposal areas; (2) Further study is needed at this time to define the extent and significance of most objectionable conditions associated with biological, chemical, and physical changes caused by disposal areas; (3) Ecological and land-use issues that are the basis for public opposition to confined disposal areas should be investigated for ways in which the Corps can mitigate these effects., Report on Dredged Material Research Program.

In recent years flow regulation by completed upstream reservoirs and project advancement to the refinement stage induced field investigations which isolated a major cause of bed roughness as a result of open spur dike systems within the concave bank control structures. To reduce the cause and effects, a new type structure was designed which consisted of a longitudinal structure designed along the concave alignment which partially closed the gap between the open spur dikes. Detailed design of this new structure called an "L-head" was varied in different areas to provide a basis for future analysis of field data to develop general design criteria., Prepared in cooperation with the U. S. Army Engineer District, Kansas City.

The existing comprehensive fixed-bed model of the Charleston Harbor system was used to conduct several special-purpose studies. These studies involved a proposed silt trap in Wando River, salinity investigations, a proposed spoil area dike, a scheme to redivert powerhouse discharge from Cooper River into Wando River, intermittent powerhouse operation to meet peak demands, and a proposed extension of the existing navigation channel in Cooper River. In general, model tests were conducted to determine the effects of the several proposals on tides, currents, and salinities throughout the estuary, and test results consist primarily of measurements of tide heights, current velocities, salinities, time-exposure photographs of surface current patterns, graphic illustrations of dye dispersion, and analyses to determine flow predominance., See also Appendix F, AD-A954 211.

Little River Channel does not have the capacity to carry flood waters. It frequently overflows, damaging homes, businesses, and public properties. Some lands are not being utilized to their highest potential due to the flood threat. The problem is becoming more acute as the City of Laurens develops. The proposed plan of improvement is clearing and snagging that portion of Little River extending from South Carolina Route 37 upstream to S.C. Route 127. Channel enlargement would extend from S.C. Route 127 upstream a distance of 2.38 miles on Little River to a point 1,640 feet above confluence with Reedy Fork Creek. Channel enlargement on Reedy Fork creek would extend from its confluence with Little River upstream a distance of 5,410 feet. The improvement ends 100 feet downstream from the dike at the Laurens municipal emergency water supply pumphouse. Right-of-way requirements will vary from 250 feet in the lower reach to 230 feet in the upper reach of Little River and 200 feet on Reedy Fork Creek. There are favorable sites for a flood control structure in the upper reach of Little River. A flood control structure did not appear to be feasible during this study but will be re-evaluated in the detailed study. Local sponsors have requested that water supply be evaluated in connection with any flood control structure.

Soules Swamp does not have a definable channel in its lower reaches. During periods of heavy rainfall, flooding occurs due to the dense growth of timber and underbrush in the flood plain. Flooding also occurs from the backwater effect of White Marsh Swamp. The drainage area of White Marsh at its confluence with Soules Swamp is about 209 square miles. When Soules Swamp overflows, flood waters damage homes, businesses, and public properties. Frequent flooding precludes the optimum utilization of some lands. The problem is becoming more acute as Whiteville continues to develop and low lands become more attractive for development because of their proximity to the business district of Whiteville. The proposed plan of improvement consists of constructing a perimeter dike with a length of 2.35 miles and a maximum height of 8.5 feet around the southern portion of Whiteville. The eastern end of the dike adjoins the Seaboard-Coastline Railroad embankment approximately 500 feet east of the town limits. The dike forms a perimeter along the southern town limits of Whiteville and adjoins the Seaboard-Coastline Railroad embankment on the western town limit adjacent to Mollie Branch and the property of Georgia-Pacific Lumber Corporation.

Report on Missouri River Design Study

Report on the Missouri River Design Study.

Confined dredged material disposal problems and practices were discussed with representatives of 17 Corps of Engineers (CE) District offices to obtain a data base for subsequent related research efforts and to disseminate the data to CE Districts and others. This report discusses only those disposal operations in which the dredged material is deposited within an area confined by natural or man-made barriers. The containment barrier may be an embankment or an open pit that will retain solids and pollutants and allow escape of less turbid and polluted water. The study dealt primarily with existing disposal sites for which pertinent data were available. In the past, little attention has been paid to the disposal of dredged material other than attempts to keep it out of the channel from which it was dredged. This practice is changing with the advent of concerted efforts by various agencies to define and control adverse effects of man's activities on the environment., Report on Dredged Material Research Program.

The general objective was to determine those properties of the asphalt mixture dropped in a mass under water which will give the best coverage, considering spread, thickness, strength or resistance to disintegration, deformability in conforming and reforming as the river bed scours, to river-bed irregularities, velocity of the water, depth of placement, and economy of placement. (Author Modified Abstract)

The report presents the results of the first year studies of a three year research contract to determine the environmental response to the deposition of dredged material on salt marshes using diked and undiked confinement techniques. The report includes studies of water quality changes, studies of salt marsh sediment responses, and biological studies directed toward identifying any changes in the biota in areas of dredging activities. (Author Modified Abstract)

The existing comprehensive fixed-bed model of the Delaware Estuary was used to determine the necessity for rehabilitating the Reedy Island and Pea Patch Island training dikes. These dikes, located adjacent to the navigation channel in the lower reaches of the Delaware River, are about 50 and 30 years old, respectively, and certain sections have deteriorated to such an extent that the cost of raising the dikes above mean high water is estimated to be about 10 million dollars. Model tests were conducted to determine the effects of various degrees of dike rehabilitation and destruction on hydraulic conditions throughout the affected area of the estuary. The test results consist primarily of current velocity measurements and time-exposure photographs of surface-current patterns. From this information it was concluded that rehabilitation of the dikes was not justified either by benefits to navigation or by decreased maintenance dredging in the navigation channel. (Author)

Fire Island Inlet, located on the south shore of Long Island, N. Y., connects the Atlantic Ocean with Great South Bay. The inlet is about 3 miles long and approximately 1/2 mile wide, extending generally east and west between Oak Beach on the north and the western end of Fire Island on the south. Great South Bay, to which Fire Island Inlet is the main entrance, is a tidal body 25 miles long and 2 to 5 miles wide with a general depth of about 6 to 25 ft at m1w. Attempts have been made to stabilize an entrance channel through Fire Island Inlet with little success. To study this problem a fixed-bed model (later converted to a movable-bed model) was constructed to scale ratios of 1:500 horizontally and 1:100 vertically, reproducing all of Fire Island Inlet and a portion of the Atlantic Ocean. Tides, tidal currents, and wave action in the Atlantic Ocean were reproduced. Results indicated that the plan originally recommended by the New York District, which included a littoral drift trap located in the entrance to the inlet, a rehandling basin in the inlet, a connecting channel of adequate depth for navigation by a loaded hopper dredge, and a 500-ft extension to the Federal Jetty. The construction of groins, deflection dikes, and closure dikes would not appreciably improve conditions obtained by the recommended plan alone. A plan involving an offshore breakwater and a littoral drift trap located between the breakwater and the beach would also function satisfactorily in every respect. (Author)

The purpose of this paper is to present the hydraulic problems relating to the computation of hurricane surge, hurricane waves, runup of the waves for providing hurricane flood protection at Texas City, Texas, as well as the effects of rainfall upon the protected area during periods of normal and high tides. The problems of providing protection are discussed, and information is presented on structures that were designed for the hurricane protection project.