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Contents: Appendix A Problem Identification; Appendix B Economic Analysis; Appendix C Engineering Investigations Design & Cost Estimates; Appendix D Formulation, Assessment and Evaluation of Detailed Plan; Appendix E Comments from Other Agencies., Appendixes to ADA115715.

This report discusses various aspects of the salinity problem in Bush Park Reservoir and, especially, operation of Lake Moultrie to control salinity downstream., Appendix A to Supplement 2, AD-A150 160.

Several alternative measures to meet the problems and needs of the area are possible; however, some of these measures are not practical or economical. Possible solutions may be divided into two broad categories of structural and nonstructural. Structural measures are designed to modify floods by altering the natural environment. These measures include alternatives which reduce flood elevations, divert floods, change the timing and duration of floods or restrict floods from portions of the flood plain. Nonstructural measures are designed to modify flood damage susceptibility and include modifications to the cultural environment by adjustment in the pattern and mode of land use, by developmental policies and by assistance to affected individuals. Also, a combination of structural and nonstructural measures is possible. Based upon information presented in this report, it is recommended that further study of flood problems in Camp Branch/Lynches Lake be authorized. Estimated study cost for completion of an expanded reconnaissance report is $114,800.

This is a compilation of letters of comment and responses thereto on the Draft Supplement to the final Environmental Impact Statement on the project., See also AD-A152 409, Appendix B, AD-A152 411 and Appendix C, AD-A152 412.

The proposed work includes construction of an 850- x 100-foot marginal pier with a 1,000-ton derrick and six dolphins, dredging an area 2,000- x 175-foot next to the wharf to a depth of -27 feet mean low water (mlw), and deposition of approximately 89,000 cubic yards of silty-fine sand in an upland disposal area. Environmental Impacts: Improvement of area economy; contribution to solution of energy problems and air pollution problem; conversion of a maximum of 145 acres of upland hardwoods to an industrialized area of 12 acres of upland hardwoods to rights-of-way for roads and utilities; the use of about 30 acres of uplands for disposal of dredged material; permanent destruction of less than one acre of saltmarsh; change in visual appearance from a natural to industrialized area; an increase in daytime noise levels from 30-35 db to about 38 db at property line; decreased probability of eagles nesting on the CB&I property; minor demands on area water supplies, schools, and services; additional air pollution from automobile exhausts of employees; and temporary construction impacts of noise, open burning, water turbidity during dredging, increased automobile traffic, and temporary disruption of benthic community in about 2,000 by 175-foot area of Colleton River; possible additional industrial development at Victoria Bluff; and preemption of designation of area as a natural landmark., See also Appendix A, AD-A152 410, Appendix B, AD-A152 411 and Appendix C, AD-A152 412.

This is a compilation of letters of comments and responses thereto on the final Environmental Impact Statement on the project., See also AD-A152 409, Appendix A, AD-A152 410 and Appendix C, AD-A152 412.

The purpose of this report is to present the basic data collected on the storm of June 1973 and the subsequent flooding which occurred along the Black and Pocotaligo Rivers, South Carolina since this was the flood of record. This report summarizes hydrologic, economic and other data which were considered of significance and were readily available. A reconnaissance of affected areas was made after the flood waters subsided for the purpose of conducting a flood damage survey. Subsequent office studies included an evaluation of flood damages and a brief hydrologic analysis Included is an evaluation of the effectiveness of the Corps' authorized Kingstree Branch Channelization project had it been operational at the time the flood occurred.

Village Creek is a typical short, meandering tidal creek along the coastline of Beaufort County, South Carolina which arises near the center of St. Helena Island and flows northeast into Morgan River, one of the tributaries of St. Helena Sound. The creek is about seven miles long and about 600 feet wide at the mouth. The creek has scalloped the low coastal lands leaving wide expanses of tidal mud flats which are covered by salt marsh vegetation. Although fed by some surface runoff, Village Creek is saline. The semi-diurnal tidal fluctuation is approximately 7.0 feet. The Village Creek Project provides for a channel eight feet deep mean low water (mlw) and 80 feet wide from the Morgan River to the uppermost shrimp boat terminal, a distance of 5.3 miles. A detailed discussion of all environmental impacts expected to result from the project is given. Some of these impacts are considered unfavorable, but cannot be avoided by any practical means within the authority and scope of the proposed project. The prinicpal adverse impacts relate to temporary changes in water quality and its effect on the creek and disposal area ecosystems. These effects include: increased turbidities and siltation in the vicinity of the dredge and disposal areas and a possible reduction in dissolved oxygen levels as a result of the dredge disturbing organic materials undergoing anaerobic decomposition. In addition, some benthic organisms may be destroyed by the dredge cutterhead or smothered in any open water disposal areas.

Environmental impacts of this project include: Short-term increase in turbidity and sedimentation; smothering of plant and animal communities in disposal areas; temporary frightening of birds and mammals in the area; temporary reduction of phytoplankton and zooplankton; possible oxygen reduction due to disturbance of anaerobic bottom sediments; short-term reduction of benthic organism populations in the path of the cutterhead and in the offshore disposal area; increase in local mosquito population; possible adverse effect of fish larvae due to increased turbidity; minor increase in air pollution during dredging operations; and stimulation of the local, state and national economy. Adverse environmental effects include: Temporary increase in turbidity and siltation in the vicinity of the dredge and disposal areas; temporary decrease in primary production resulting from turbid waters; possible loss of organisms through leaching of toxic substances from upland disposal areas; possible reduction in dissolved oxygen levels as a result of the dredge disturbing organic materials undergoing anaerobic decomposition; possible displacement of wildlife species; alteration of existing vegetation in disposal areas; destruction of some benthic organisms by the cutterhead; and increase in the local mosquito population., Original contains color plates: All DTIC and NTIS reproductions will be in black and white.

This supplement contains letters of comments and response to the final environmental statement in connection with an application permit to dredge and construct a pier at Victoria Bluff South Carolina., See also AD-A152 409, Appendix A, AD-A152 410 and Appendix B, AD-A152 411.

The recommended plan of improvement for Wilson Branch consists of demolishing six houses which lie below the 10-year flood plain on Wilson Branch. These six adjacent houses lie in a reach from 500 to 1500 feet from the mouth of Wilson Branch. All disturbed areas would be planted with grass, shrubs and trees to prevent erosion and to restore a natural appearance. Project lands would be obtained and controlled by the local project sponsor for maintenance purposes. Local project sponsors must also enforce flood plain ordinances to assure that any future development of the residual flood plain would be compatible with the flood hazard. Estimated first cost for implementation of the recommended plan is $314,590 plus an additional $120,000 in related cost for the relocation of current occupants of affected flood plain structures. Average annual project benefits resulting from the implementation of the recommended plan of improvement are estimated to be $27,440 in flood damage reduction benefits to existing development., Revision of report dated Jun 82, AD-A132 432.

The South Carolina State Ports Authority dredged a channel 325 feet by 450 feet in the Wando River from the Charleston Harbor Federal Navigation Project to its newly constructed terminal facilities adjacent to Hobcaw Creek in the summer of 1981. This report presents the engineering, economic, and environmental studies conducted to determine the advisability of maintaining and deepening this locally-dredged channel. Since the site of the terminal facilities and channel is set, the usual technique of analyzing conditions and solutions by examining a wide range of alternatives was not considered necessary. The only alternatives were Federal adoption of the existing 35-foot deep channel and channel deepening. Based on the results of this study, it is concluded that the most economically feasible plan for satisfying future harbor needs consists of maintaining and deepening the locally-dredged channel to -40 feet mean low water datum in the Wando River. It is, therefore, recommended that the Charleston Harbor Navigation Project be modified to add the State's Wando channel to the project and to deepen this segment to 40 feet when similar depths are provided in ocean connecting reaches., Original contains color plates: All DTIC and NTIS reproductions will be in black and white. Revision to report dated Jan 84. See also Appendices, AD-A155 885.

Report of investigations to determine feasibility of providing flood control and related water resource improvements on various streams within the Sugar Creek Basin, North Carolina and South Carolina. The report recommends construction of a combination of structural and non-structural flood damage prevention measures and discusses the impacts of implementation.

Construction in the drainage basin has exceeded the development predicted in the previous study which was the basis for design of the existing project. Therefore, flooding of the Sawmill Branch has become more frequent in the past few years. The flood problems discussed in this report are based on information obtained from local officials; topographic mapping with ten-foot contour intervals, and a field reconnaissance by the Corps' study team. Local officials report that flooding occurs more often due to intensified urban development. This development has completely changes the hydraulic conditions of the area and placed a tremendous strain on the drainage capacity of Sawmill Branch. The objectives of this phase of the investigation are to determine the feasibility of further Federal involvement in addressing the flooding problems and to develop a detailed study plan. Should further study be needed, the objectives would be to formulate alternative measures to reduce flood damages and to select the best course of action to alleviate these problems.

The most desirable plan from an economic safety and environmental standpoint would provide for a channel 40 feet deep and 450 feet wide from the existing Charleston Harbor project to a turning basin with a turning diameter of 1200 feet. Appendixes: A: Study Authorizations, Prior Reports and Public Meetings; B: Problem Identification; C: Economic Analysis; D: Engineering Investigation Design and Cost Estimates; E: Environmental Analysis; F: Formulation, Assessment and Evaluation of Detailed Plan; G: Comments from Other Agencies., Appendices to AD-A155 885. Revision to report dated Jan 84.

The most appropriate plan of improvement in the Leith Creek Basin is a combination structural and nonstructural plan. The structural measures consist of cleaning and widening the existing channel for a total distance of 1.97 miles, replacing two highway bridges and relocating two water mains and one sewer line. Nonstructural measures consist of passage, by the local sponsor, of regulatory measures to control the residual flood plain. The concept of designated floodways is recommended. Recreational facilities in the form of a linear greenway with bike trail and picnic tables are also included as part of the recommended plan. The selected plan will provide net economic and environmental improvements to the area. The proposed action will have no significant adverse effect on the environment and is not environmentally controversial.

Description of Action: Work in the Cooper River as follows: Construction of a 40-by 108-foot pier, a 38- by 6,314-foot pipeline trestle supporting 4 pipelines and a roadway, and two breasting dolphins and four mooring dolphins connected to the pier by two 4- by 350-foot walkways; excavation of a 155-by 300-foot barge slip having a depth of 10 feet MLW with sheetpile bulkheads and timber dolphins, dredging of a 200- by 1,000-foot canal between Cooper River and Grove Creek, and dredging of an 80-foot channel with a depth of 10-feet MLW Grove Creek, to the barge slip, and a 400 by 7,200-foot channel with a depth of 35 feet MLW in Cooper River; and the disposal of about 1.3 million cubic yards of dredged material in the Yellow House Creek Disposal Area. Table of Contents: Project Descriptions; Environmental Setting without the Project; Relationship of the Proposed Action to Land Use Plans; The Environmental Impact of the Proposed Action; Any Probable Adverse Environmental Effects which cannot be Avoided; Alternatives to the Proposed Action.

The W. Kerr Scott Reservoir is a multiple-purpose project operated for flood control and water supply. The original controlled capacity at spillway elevation of 1,075 feet was 154,000 acre-feet. The purpose of this report is to make an evaluation of sedimentation problems related to the presence and operation of the W. Kerr Scott Reservoir, and determine if the accumulated volume of sediment is sufficient to warrant revising the original stage-capacity curve. This report evaluates the monitoring program for the project and serves as an instrument for documenting basic field data essential for this and future efforts., Original contains color plates: All DTIC and NTIS reproductions will be in black and white.

Crooked Creek is a tributary to the Great Pee Dee River located in the northeastern portion of South Carolina in Marlboro County. A preliminary assessment of environmental concerns of the study area is attached as Inclosure 2 to this report. Flooding of the Bennettville urbanized area extending from Lake Wallace Dam to Rodgers Street Extension is the problem being addressed by this study. The objectives of this phase of the investigation are to determine the feasibility of further Federal involvement in addressing the flooding problems and to develop a detailed study plan. Should further study be needed, the objectives would be to formulate alternative measures to alleviate flood damage and to select the best course of action to alleviate these problems.

Description of Action: Maintenance of a channel 12 feet deep at mean low water and not less than 90 feet wide in the Atlantic Intracoastal Waterway from Little River to and including Port Royal Sound, with a branch channel to the same dimensions to McClellanville, a total distance of 210 miles. Environmental impacts: Short-term increase in turbidity and sedimentation; smothering of plant and animal communities in disposal areas; temporary frightening of birds and mammals in the area; temporary reduction of phytoplankton and zooplankton; short-term reduction of benthic organism populations in the path of the cutter-head; increase in the local mosquito population; possible adverse effect on fish larvae due to increased turbidity; possible reduction in dissolved oxygen levels as a result of the dredge disturbing organic materials undergoing anaerobic decomposition; minor increase in air pollution during dredging operations; and improvement of navigation with associated benefits to commercial shippers, the fishing industry, and recreational boaters.

The purpose of this project is to provide safe navigation for existing and prospective vessel traffic by establishing and maintaining a safe navigation channel from the 12-foot contour in the open ocean to the village of Murrells Inlet, and constructing a turning basin and jetties. This final environmental impact statement presents the recommended plan of improvement consisting of the following: dredging an entrance channel, 300 feet wide and 10 feet deep through the offshore bar, a distance of approximately 3,000 feet; dredging an inner channel, 200 feet wide and 10 feet deep for a distance of 1,850 feet then, 90 feet wide and 8 feet deep to the major berthing area at old Army crash boat dock, a distance of 13,590 feet where it would terminate in a turning basin 300 feet long and 150 feet wide; dredging a deposition basin 18 feet deep adjacent to the weir section of the north jetty; constructing a north jetty 3,455 feet long with a low weir section for sand bypassing; constructing a south jetty 3,330 feet long; constructing a fishing walkway on top of the south jetty; and constructing sand dikes on both sides of the inlet to tie the jetties to the existing dune line. Additional keywords: Army Corps of Engineers; South Carolina., Original contains color plates: All DTIC and NTIS reproductions will be in black and white.

The purpose of this Lakeshore Management Plan is to establish a policy which will provide guidance for the protection and preservation of the desirable environmental characteristics of W. Kerr Scott Reservoir. Also, this policy will provide for the gradual restoration of any portions of the lakeshore where changes have taken place due to private exclusive use. This Lakeshore Management Plan is being prepared as Appendix F to the Master Plan for Recreational Development and Management of W. Kerr Scott Reservoir. The plan is summarized as follows: (a) to manage and protect the shorelines (lakeshores) of all lakes under the jurisdiction of the Chief of Engineers; (b) to properly establish and maintain acceptable fish and wildlife habitat, aesthetic quality and natural environmental conditions; (c) to promote the sale and healthful use of these shorelines (lakeshores) for recreational purposes by all people; (d) to provide ready access and exit from these shorelines (lakeshores) by the general public; (e) to encourage boat owners to moor their boats at commercial marinas, utilize dry storage off project lands or trailer their boats to public launching ramps which are provided by the Corps of Engineers., Original contains color plates: All DTIC and NTIS reproductions will be in black and white.

This memorandum presents information describing a proposed fish hatchery, including plans, costs, justification and design criteria. The proposed fish hatchery is of the same general design as the present hatchery at Moncks Corner with only minor modifications made, without betterment, in the floor plan and equipment, at the request of the South Carolina Wildlife and Marine Resources Department. This report is submitted for approval of the proposed fish hatchery plan to serve as a basis for subsequent contract negotiations, detailed plans and specifications, and ultimate construction. This memorandum provides a detailed design for the new fish hatchery which will replace existing Moncks Corner fish hatchery. The following items are included: (a) Report of necessity. (b) Criteria for Design and Specifications for use in preparing construction plans and specifications for the work recommended in this FDM. (c) Cost analysis and detailed drawings of the proposed fish hatchery building and related appurtenances and equipment for the operation of the hatchery. (d) The legal obligations of the United States Government are discussed in the agreement between the Corps of Engineers and the South Carolina Wildlife and Marine Resources Department, Appendix A.

The recommended plan provides for beach restoration, erosion control and improvement of recreational beach along the ocean shoreline of Folly Beach, South Carolina. The plan improvement provides for restoration and periodic renourishment of a continous reach of beach in the center section of the Folly Island ocean shoreline for a total project length of 16,860 feet. The plan would require 684,000 cubic yards of sandy fill material. Borrow areas selected as a source of fill sand are shoal areas in Lighthouse and Stono Inlets. Beach nourishment and restoration would create and maintain a total of 23 acres of beach which would bring about an increase in recreational activity and reduce beach erosion which currently endangers oceanfront development. Minor and temporary impacts include the disruption of benthic populations, increase in water turbidity, reduction in aesthetic values during construction, possible improvement of the navigability of inlets due to the removal of shoal material and increase in auto emissions and noise levels during peak activity periods., Revision of report dated 28 Mar 80, AD-A115709.

Heavy siltation of Charleston Harbor has caused the US Army Corps of Engineers to consider plans to divert the major flow of fresh water through a new canal to be constructed from the Lake Marion-Lake Moultrie-Cooper River complex to the Santee River. The US Geological Survey was asked to study the effect such a canal would have on the ground-water regimen of the area. The drilling phase of the study consisted of 33 core holes located along and at right angles to the canal right-of-way. The purposes of the core holes were to delineate the subsurface geology and to locate possible sites for the observation well network. As a result, 20 observation wells were drilled in order to monitor water levels before, during, and after construction of the canal and power house. As a result of the drilling program three aquifers in the study area were delineated: aquifer 1, a shallow (40-60 feet) sand which supplies limited amounts of water to wells; aquifer 2, a confined limestone (90-120 feet) which is the most widely used aquifer in the vicinity of the canal right-of-way; and aquifer 3, a sand and gravel remnant of a buried stream channel found in the flood plain., See also Appendix A, AD-A149 576.

The purpose of this project is to provide safe navigation for existing and prospective large vessel traffic by deepening existing channels providing new and enlarged turning basins, and providing minor alignment changes and easing of bends. The proposed plan of improvement for Charleston Harbor consists of the following: (a) Deepening the existing entrance channel from a depth of 35 feet to a depth of 42 feet; (b) Deepening the existing entrance channel from a depth of 35 feet to a depth of 40 feet from the Entrance Channel (Mile 0.6) to Mile 15.7 at Goose Creek; (c) Deepening the Shipyard River channel from 30 feet to 38 feet; (d) Enlargement of the anchorage basin at the harbor mouth; (e) Enlargement of the existing turning basin at the head of the commercial channel; (f) Dredging a new turning basin adjacent to the Columbus Street docks; (g) Widening North Charleston and Filbin reaches to 500 feet; (h) Shifting of channels near the various terminals to provide 125 feet between existing piers and the edge of the channel., Original contains color plates: All DTIC and NTIS reproductions will be in black and white.

This is an invitation to bid on a civil works program in South Carolina for Lake Moultrie and the Santee River. EEO information administrative bid requirements, forms for showing prices and contracts, the general provisions of the construction contract, the safety inspection check lists, equipment specifications, and Boring Logs are included.

The proposed program provides for a comprehensive plan to control noxious aquatic plants within the state waters of South Carolina in the interest of navigation, flood control, agriculture, fish and wildlife, public health, and other related purposes. Target species include alligator weed (Alternanthera philoxeroides), Brazilian elodea (Egeria densa), and water primrose (Ludwigia uruguayensis). Alligator weed would be controlled by an integrated program involving biological control and herbicides. Brazilian elodea and water primrose would be controlled primarily by herbicides. Other treatment methods acceptable under the recommended plan include mechanical harvesting and fiberglass bottom screens. The selection of treatment methods for individual sites would be the responsibility of the Corps in cooperation with the local sponsor. The control program has been tentatively selected based on its performance in addressing the identified public concerns and its net positive contributions to the goals of National Economic Development and Environmental Quality., Original contains color plates: All DTIC and NTIS reproductions will be in black and white.

This report is the result of a small navigation study conducted at the request of Charleston County to explore the feasibility of dredging several shoals which have developed in Folly River and Stono Inlet and are hindering navigation there. The material contained in this report is organized to give the reader an understanding of: (1) the nature of the problems involved and the type of setting in which they occur; (2) the choices that were available in formulating different plans of solution; (3) how and why the selected plan was chosen; (4) the overall effect of the selected plan in various areas of concern. The purpose of this study was: (1) to determine the need for and advisability of providing and maintaining a shallow draft navigation channel from upstream docking areas on Folly River and Folly Creek through Stono River Inlet to the Atlantic Ocean off Charleston County; (2) to determine what, if any, other water and related land resource needs exist in the area; (3) to determine what different management measures could be taken and (4) to select those which would best address those needs.

This is a compilation of letters of response from interested organizations and individuals., See also Volume 1, AD-A152 525.

Carolina Refining and Distributing Company has applied for a permit to install two underwater pipelines across the Sampit River to transport crude oil and refinery products between the S C. State Ports Authority pier and a proposed new oil refinery. This proposed refinery would enlarge the economic base of Georgetown County, one of the most economically depressed counties in South Carolina. The operation of the proposed refinery would however impact on air and water quality and aquatic resources in the area. These adverse impacts caused by air emissions and liquid effluents can be avoided or their severity reduced by the use of better treatment methods now available. Winyah Bay is surrounded by marshes and other natural areas, much of which are maintained in the public trust by State agencies and institutions and are considered to be of unusual value. Large oil spills are very unlikely but could cause extensive long-term damage to these areas. However, the Spill Prevention Control and Countermeasure Plan and the Operations Manual required by existing law provide measures to prevent and control oil spills., See also Volume 2, AD-A152 526. Errata sheet inserted.

This report presents the engineering, economic and environmental studies conducted to determine the advisability of modifying the existing project in compliance with four Congressional Resolutions. Various solutions to the problems and needs of the Port of Georgetown were analyzed. Based on the results of this analysis, the District Engineer finds that there is no economically-feasible plan for modifying the existing Federal navigation project. The District Engineer, therefore, recommends no plan of improvement as a result of this report.

The purpose of this design memorandum is to present for review and approval a detailed paln for monitoring water quality, flows and stage in the water systems which are expected to be subject to significant project effects and determining the effect of freshwater flow changes in the Cooper River on the hydraulic, slainity, and shoaling characteristics in Charleston Harbor. The present plan includes costs for equipment, operation and maintenance, and details of information to be collected by the program. This design memorandum covers pre-project as well as post-project conditions to permit necessary comparison of data to determine project impacts. The monitoring arrangement for the Cooper River would be sufficiently sophisticated to permit early warning necessary to make appropriate releases in accordance with the operations manual at the Jefferies Hydroplant to repel any salinity threat to industries utilizing Bushy Park Reservoir as a source of fresh water. The monitoring arrangement for Charleston Harbor would provide information on stratification and shoaling., Original contains color plates: All DTIC and NTIS reproductions will be in black and white. Includes errata sheets dated 10 Apr 78 and 10 Feb 78.

Conclusions include: (1) Studies performed for this report have adequately considered canal and interior drainage design alternatives; (2) The intake and tailrace canals alignment proposed in this report is the most economical alignment and has the least adverse environmental impact of alternatives considered; (3) The proposed interior drainage system is the most economical and feasible method of handling intercepted drainage of the alternatives considered; and (4) The canal design adequately considers earthquake effects on the canal and levee structures., Original contains color plates: All DTIC and NTIS reproductions will be in black and white. See also Appendix A, AD-A149 732.

Maintenance of a channel 27 feet deep and 500 feet wide across the ocean bar and in Port Royal Sound; 24 feet deep and 300 feet wide in Beaufort River and Battery Creek; and a turning basin 27 feet deep by 600 feet wide opposite the State Ports Authority wharf. Short-term increase in turbidity and sedimentation; smothering of plant and animal communities in disposal areas; short-term reduction of benthic organism population in path of cutterhead and in offshore disposal area; possible increase in local mosquito population; minor increase in air pollution during dredging operations; and stimulation of local, State, and national economy. Temporary increase in turbidity and siltation in vicinity of the dredge and disposal areas; possible displacement of widelife species; disruption of benthic invertebrates in path of cutterhead and in open water disposal area; alteration of existing vegetation in disposal area; and possible increase in local mosquito population.

Work on the Wando River will consist of: Construction of a 135- by 5000-foot concrete wharf supported by prestressed concrete piles; construction of a sheet steel bulkhead to the rear of the wharf; construction of ten cranes (8 container and 2 gantry canes) on the wharf; construction of a 12- by 350-foot prestressed concrete pile supported railroad trestle; construction of a barge slip with two 12- by 220-foot prestressed concrete docks, 42 feet apart; dredging a berthing facility area approximately 5,600 feet in length with varying widths from 125 to 500 feet to a depth of -40.0 feet mean low water; the deposition of approximately 3,780,000 cubic yards of unusable material (silt and mud) in the Morris Island disposal area and 915,000 cubic yards of suitable material (sand) on the terminal site for use behind the bulkhead as fill; dredging a channel 500 feet wide to a depth of -40 feet mean low water for a distance of about two miles to the existing channel in the Cooper River; dredging a 1,000-foot turning basin; and the deposition of approximately 2,500,000 cubic yards of material dredged from the channel and turning basin in the Morris Island disposal area. Work on the Cooper River will consist of: constructing a barge slip with two 12- by 200-foot prestressed concrete docks 42 feet apart; dredging an area 1,420 by 100 feet to a depth of -25.0 feet mean low water; and the deposition of approximately 250,000 cubic yards of silt and mud in the Daniel Island area, if available, or alternatively in the Morris Island disposal area.

This compilation of specifications and regulations also includes technical provisions for environmental protection, boring logs, and statistical data on surface winds.

The recommended plan of improvement consists of the following: dredging an entrance channel, 300 feet wide and 12 feet deep through the offshore bar, a distance of approximately 5,160 feet; providing an inner channel, 90 feet wide and 10 feet deep from the entrance channel to the Atlantic Intracoastal Waterway, a distance of 11,000 feet; dredging the lower 5,200 feet of the inner channel; dredging an upcoast deposition basin adjacent to the weir section of the north jetty to a depth of -20 feet to provide a capacity of 200,000 cubic yards; constructing a north jetty 3,385 feet long with a low weir section for sand bypassing; constructing sand dikes on both sides of the inlet to tie the jetties to the existng dune line; and possibly constructing a fishing walkway on top of the south jetty. The adverse environmental effects will be temporary increase in turbidity; alteration of existing vegetation during construction of south sand dike; temporary disturbance of birds and mammals in the area; destruction of some benthic organisms by dredge cutterhead; smothering of invertebrates under jetty stone and in beach disposal area; and possible displacement of wildlife species., Original contains color plates: All DTIC and NTIS reproductions will be in black and white.

This memorandum concludes that: (1) the proposed action is based on thorough analysis and evaluation of various practicable alternative courses of action for achieving the stated objectives; (2) the adverse effects found to be involved cannot be avoided by following reasonable alternative courses of action which would achieve the considered purposes; (3) where the proposed action had an adverse effect, this effect is either ameliorated or substantially outweighed by other considerations of national policy; and (4) the recommended action is consonant with national policy, statutes and administrative directives, and, on balance, the total public interest would best be served by the implementation of the recommendations., Original contains color plates: All DTIC and NTIS reproductions will be in black and white.

This supplement presents modifications of the channels, jetties and weir system that were previously submitted for approval. The major revisions occurred as a result of model test data developed by WES subsequent to submission of the GDM. Other changes were made as a result of a conference held at SAD on 20 August 1976 concerning design of weir jetty structures. This supplement covers changes in jetty and channel configuration resulting from model testing of Plans 7A, 7B, Plans 1B through 1H and from innovative changes in weir system design. It also presents a summary of the WES model results for all plans tested. A comprehensive report of the model testing program for the Murrells Inlet Navigation Project will be submitted as a separate appendix (to the General Design Memorandum) at a latter date. A revised project cost estimate considering the various changes is presented. A physical model of Murrells Inlet and estuary was constructed at WES to evaluate the effects of currents and wave action on different arrangements of the jetty system under simulated prototype conditions. This fixed bed model was constructed to 1:200 horizontal and 1:60 vertical scales., Original contains color plates: All DTIC and NTIS reproductions will be in black and white.

This report has been developed to fill the need for flood information at various locations along Lumber River. The study was initiated as a result of a request from the State of North Carolina for floodway mapping in the vicinities of Lumberton, Boardman and Fairbluff, North Carolina. Various other requests indicated the need for information along the entire reach of Lumber River from the mouth to the town of Lumberton. Flood information within the corporate limits of Lumberton has been developed by the Corps of Engineers under contract for the Federal Insurance Administration and will be published in a separate report. Flood information presented in this report will not conflict with data which will be presented in the Lumberton Flood Insurance Report. No other flood insurance studies have been completed or are in progress which will affect the study area covered in this report. In the future, some of this land is likely to be considered for industrial sites, waste treatment facilities and other uses. Knowledge of the flooding potential is an important factor in selecting, financing and insuring various types of development., Original contains color plates: All DTIC and NTIS reproductions will be in black and white.

The authorized plan for navigation improvement consists of the following: dredging an entrance channel, 300 feet wide and 12 feet deep through the offshore bar, a distance of approximately 3,300 feet; an inner channel, 90 feet wide and 10 feet deep from the entrance channel to the major berthing area at the old Army crash boat dock in the village of Murrells Inlet, a distance of 15,700 feet, where it would terminate with a turning basin; a 16-acre diked disposal area to accomodate shoal material found unsuitable for beach nourishment; a jetty on the north side of the inlet approximately 3,300 feet long, having a low weir section over which littoral materials pass en route to a deposition basin; a south jetty, approximately 2,300 feet long; and sand transition dikes connecting the jetty structures to the shore. The main recreational feature in the authorized project is an 8-foot wide fishing walkway to be constructed along the entire length of the south jetty. For public access, an existing road from Huntington Beach State Park would extend from the present parking area to the proposed south jetty. Public accomodations in the park would be readily available for fishermen using the walkway., Original contains color plates: All DTIC and NTIS reproductions will be in black and white.

The focus of this study is on the hydrographic and geographic characteristics of South Carolina streams discharging into the ocean from the perspective of their usefulness for barge commerce. For the purpose of this report the design tow consists of a tug and a lash barge. The tug is assumed to be 35 feet long and the lash barge 60 feet long. The beam width critical to the movement of this tow is the 30-foot beam of the barge. To be minimally functional for navigational use by this design tow would require a depth of 9 feet, horizontal clearance of 60 feet, and vertical (overhead) clearance of 30 feet. Information contained in this report was compiled from literature and recent field inspections. Depths observed during these field inspections were spot soundings made generally along the thalweg using a fathometer and/or weighted line. More detailed examination of the streams would be required to define the availability of the horizontal and depth clearances needed. Results of the investigation are reported in detail and summarized in tabular form in the following table. The upper limits of navigation are given assuming little or no modification of existing channels would be made, and secondly, assuming extensive channel modification., Original contains color plates: All DTIC and NTIS reproductions will be in black and white.

This memorandum presents information describing the effects of the project on the Seaboard Coast Line Railroad Facilities and a proposed relocation plan, including costs, justification and design criteria, which would provide appropriate and reasonable compensation to the railroad. This report is submitted for approval of the relocation plan to serve as a basis for subsequent contract negotiations, detailed plans and specifications, and ultimate construction. A detailed study was made and a solution is proposed for the problem created where the proposed tailrace canal sever the Seaboard Coast Line Railroad track at Mile Post A-347.96 (centerline canal approximately 211.2 feet north of MP A-348).

The Sugar Creek Basin Study has progressed to the point of identifying existing and anticipated future flooding problems and formulating potential structural and nonstructural alternatives for the reduction of flood damages within the Sugar Creek Basin. In order to formulate alternative plans of improvement, high damage areas were identifed based on existing and projected future flood stages. Structural alternatives were formulated for each high damage reach. These alternatives consist of a variety of flood control measures including channel modifications, bridge alterations, paved channels, covered floodways, levees, floodwalls and reservoir storage. Nonstructural alternatives, which generally consist of the evacuation of flood plain structures from the flood plain, have also been formulated for all damage areas within the basin. Plans which emphasize contributions to the improvement of environmental quality of the area and the National Economic Development will also be identified during the process of selecting a recommended plan of improvement., See also AD-A149 789.

Two sets of impervious test fills were constructed. One test set was built using materials excavated from the the Intake Canal; the other set with similar materials excavated from the Tailrace Canal. All soils used to construct the embankments were taken from the upper 10 feet. Primarily, the test fills were constructed to determine, prior to issuing plans and specifications, the combination of number of passes, lift thickness and moisture content range (using a standard sheepsfoot roller) that provided 95% compaction with the least construction effort. Also, information relating to processing of soils to obtain desired ranges of moisture was gained and is discussed. The objective was (1) to determine the character of the soil materials to be excavated by common methods, (2) to determine the ability of the rock material (shale, limestone - Intake Canal, and shale, siltstone, and sandstone - Tailrace Canal) to be excavated using a dragline bucket, and (3) to develop correlations between materials excavated during this activity and those presented on the previously drilled boring logs. The test excavations were located within the channel prism of the Intake and Tailrace Canals, respectively.

A combination of structural and non-structural flood control measures have been determined to be the best solution for the Leith Creek flood problem. The best plan to provide a high degree of protection to the Leith Creek basin would involve construction of channel conveyance improvements at an estimated first cost of $181,000 and an estimated average annual cost of $13,900. Total average annual benefits from this plan are estimated at $23,250. Adverse environmental effects are minimal due to the relatively small size of the project and environmental gains are produced by the recommendation of bridge modifications which in the past have reduced natural channel capacities. Recreational facilities consisting of a greenway with bike trail, picnic facilities and park benches are also recommended as part of the proposed plan. The estimated additional first cost for providing these facilities is $18,200 which would be apportioned on a 50/50 cost basis between Federal and non-Federal interests. Average annual cost of recreational facilities is estimated to be $1,700. Total average annual recreational benefits are estimated at $2,600. Total first cost of the flood control/recreation plan is $199,200. Average annual costs of $15,600 when compared to annual benefits of $25,850 yield a benefit-to-cost ratio of 1.66., Original contains color plates: All DTIC and NTIS reproductions will be in black and white.

The Sugar Creek Basin Study has progressed to the point of identifying existing and anticipated future flooding problems and formulating potential structural and nonstructural alternatives for the reduction of flood damages within the Sugar Creek Basin. In order to formulate alternative plans of improvement, high damage areas were identified based on existing and projected future flood stages. Structural alternatives consist of a variety of flood control measures including channel modifications, bridge alterations, paved channels, covered floodways, levees, floodwalls and reservoir storage. Nonstructural alternatives, which generally consist of the evacuation of flood plain structures from the flood plain, have also been formulated for all damage areas within the basin. Plans which emphasize contributions to the improvement of environmental quality of the area and the National Economic Development will also be identified during the process of selecting a recommended plan of improvement., See also AD-A149 790.

The results of previous studies indicated that rediversion of a major portion of the Santee River flow from Cooper River back to the Santee River is the best way to obtain a substantial reduction in maintenance dredging in Charleston Harbor. However, continuation of as much flow as possible through Pinopolis was considered desirable to minimize change to the Cooper River and harbor environment and to accommodate downstream needs of Bushy Park Reservoir at mile 43 and the Jefferies Stream Electric Generating Plant just below Pinopolis. The purpose of the model study was to determine the effects on tidal heights, current velocities, and salinities of various weekly hydrographs at Pinopolis which could result from the proposed rediversion project. The existing hydrograph has a weekly average flow of 15,600 cfs. Five suggested rediversion schedules were tested, including three with a weekly average flow of 3000 cfs and two with a weekly average flow of 3500 cfs., Supplement to report dated 14 Dec 76.

This report consists of (1) boring logs giving the type and depths of foundation soils and rock, and (2) tables and graphs giving the results of laboratory tests of the physical and mechanical properties of soil samples (mostly clay and sand).