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Source: https://erdc-library.erdc.dren.mil/jspui/ 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 proposed State park complex on the Jersey City waterfront, just west of Ellis and Liberty Islands. The study included tests in the model of seven different park configurations to define their effects on tidal heights, current velocities, surface current patterns, salinities, and flushing characteristics of a proposed Serpentine (a tidal-influenced canal west of the park area). Based on the results of the model tests, the following conclusions were reached: (A.) none of the plans tested would have any significant effects on tidal heights or tidal phasing in the study area; (B.) the plans tested would not significantly change the velocity regime of the area, except very locally and with magnitudes not thought to be hazardous to safe navigation or to increase the existing erosion potential of the area; (C.) the existing salinity regime of the area would not significantly change as a result of the plans tested; (D.) in plans 1, 4, and 7 which include the Serpentine, mass flow will occur through the Serpentine, and a small gyre rotating counterclockwise will develop at the approximate location of salinity and dye sta 2, indicating no through flow at this station, only rotational motion; and (E.) dye released at the westernmost end of Morris Canal Basin will move through the Serpentine and be flushed out the south end of the Serpentine, resulting in increased dye concentrations in the wildlife area and a lesser increase at the south entrance to the Serpentine._x000D_ _x000D_ NOTE: This file is large. Allow your browser several minutes to download the file.

Source: https://erdc-library.erdc.dren.mil/jspui/ Maintenance of Southwest Pass, one of the three major outlets of the Mississippi River, is a continuing and expensive problem due to extensive shoaling, primarily near the ends of the jetties and, to some extent, throughout the entire length of the pass. This report and Appendix A present the results of the model studies conducted to determine the effectiveness of proposed plans (e.g., lateral spur dikes, sediment diversion channel, sediment basin, relocation of the jetty channel, lateral spur dike extensions, and friction chambers) for the elimination or reduction of maintenance dredging in Southwest Pass and in the jetty and bar channels. Results of tests of Report 2 and Appendix A indicate some slight reductions in overall channel shoaling. Most of the test results indicate that there would be a redistribution of the shoal material in Southwest Pass; however, none of the plans tested caused movement of a significant quantity of shoal material into the Gulf._x000D_ _x000D_ NOTE: This file is large. Allow your browser several minutes to download the file.

Source: https://erdc-library.erdc.dren.mil/jspui/ This report contains Appendices A and B for Technical Report HL 75-13 "Mobile Bay model study. Report 1, Effects of proposed Theodore Ship Channel and disposal areas on tides, currents, salinities, and dye dispersion"

Source: https://erdc-library.erdc.dren.mil/jspui/ The Rigolets model was a fixed-bed model constructed to undistorted linear scale ratios of 1:100 horizontally and 1:100 vertically. The region reproduced by the model is 3.2 miles of the Rigolets, starting at the Lake Pontchartrain entrance of the Rigolets. The model was equipped with the necessary appurtenances for reproduction of steady-state flow in both ebb and flood directions and accurate measurement of water-surface elevations and currents under this condition. Verification tests were conducted to make certain that the model hydraulic regimen agreed with that of the prototype. The agreement attained between water-surface elevations and current velocities from similar model and prototype conditions was considered satisfactory. The testing program consisted of water-surface elevations, current velocities, and surface current patterns for various control structure plans. Plan 1 tested in the Rigolets model is identical to the plan that was tested in the Lake Pontchartrain model in the Rigolets Pass, the results of which were published in Technical Report No. 2-636, "Effects on Lake Pontchartrain, Louisiana, of Hurricane Surge Control Structures and Mississippi River-Gulf Outlet Channel." That report concluded that the hurricane control structures would not significantly affect the hydraulic or salinity regimen of Lake Pontchartrain. Test results showed plan 2 to be about equal in discharge capability with plan 1, while plans 2A and 2B were judged superior in discharge capability compared with plan 1. Possible scouring problems near the Fort Pike State Monument were noticed during testing of plans 2, 2A, and 2B. To remedy this situation a modification to plan 2A was made. The structure was shifted 250 ft away from the Fort Pike bank of the Rigolets Pass. This modification is referred to as plan 2A-1. This plan proved to have superior discharge capability relative to plan 1 as well as to reduce possible scouring problems near the Fort Pike State Monument. Additional data which were taken for each plan in the navigation canal with the lock open are presented in Appendix A.

Source: https://erdc-library.erdc.dren.mil/jspui/ This report is the second in a series of reports on the results of model tests on the Mobile Bay model. Report 1 covers the verification and effects of the proposed Theodore Ship Channel and Disposal Areas on tides, currents, salinities, and dye dispersion. Model tests in this report (Report 2) were chiefly designed to determine the impact of widening and deepening of the navigation channels and the accompanying dredged material disposal islands on tides, currents, salinities, and dye- dispersion patterns in Mobile Bay. The test results consist of comparable measurements of tide heights, current velocities, salinities, and dye-dispersion patterns for existing and proposed conditions. There was very little change in the tide heights in the bay for any plan. In general, for all plans an increase in maximum velocity occurred at stations in the low-velocity regions (the central region of the channel) and essentially, no change or a slight reduction in maximum velocity occurred at stations in the high-velocity regions (the upper and lower reaches). Enlargement of the channel seemed to be the dominant cause of salinity changes in the bay. All the plans generally raised the average salinity of the upper (north) bay and lowered the average salinity in the lower (south) bay. No plan maintained status quo (change at 0.5 ppt or less) in all four critical oyster-bed areas for area-average salinity or average bottom salinity._x000D_ _x000D_ NOTE: This file is large. Allow your browser several minutes to download the file.

Source: https://erdc-library.erdc.dren.mil/jspui/ The existing comprehensive fixed-bed model of James River was used to study the major disposal areas used during maintenance dredging operations for the existing 25-ft-deep navigation channel to determine if the disposal areas are performing satisfactorily in terms of retaining dredged material placed therein. If the test results indicated a probable excessive rate of return of dredged material to the channel, the tests were expanded to include studies of an alternate area or areas in the same general vicinity to determine if a more suitable disposal area could be defined. The tests consisted of the release of lightweight sediments at surface depth in the disposal areas, tracing patterns of movement of material from the areas, and defining areas where these sediments would probably deposit. The results indicated that, in general, the disposal areas and operating procedures presently employed are satisfactory with respect to areas of material deposition and material retention characteristics. Maintenance requirements for the Skiffes Creek channel would probably be reduced if use of the downstream 4000 ft of the Tribell shoal disposal area is shifted to the opposite side of the channel. A significant portion of the material discharged in the downstream 8450 ft of the Goose Hill shoal disposal area returns to the navigation channel, and shifting that portion of the disposal area to the north side of the channel should improve this condition. Releasing material in the Jordan Point-Windmill Point disposal area 2 results in rapid filling in Herring Creek which is probably objectionable. The sediment trap suggested for the Jordan Point-Windmill Point shoal reach would not function to the extent required and is not recommended. The estimated annual loss of depth in all disposal areas tested, except at the downstream half of Jordan Point-Windmill Point shoal reach, was 0.10 ft or less for the present shoaling rates, indicating an extended period of future use without adverse effects. The estimated annual loss of depth in the downstream Jordan Point-Windmill Point disposal areas 1 to 5 varied between about 0.10 and 0.40 ft, indicating this reach to be the most critical with respect to continuing present channel maintenance practices. Alternate disposal schemes for this reach should be developed. Further tests should be conducted in the model to determine the effects of filling the disposal areas to minimum allowable depths. For example, the disposal areas could be completely filled to some assumed condition that would exist in the future because of continued use. The disposal tests could be repeated for the future filled condition to determine associated changes in hydraulic, salinity, shoaling, and dispersion conditions. Estimates of the environmental impact of all disposal areas could then be made.

Source: https://erdc-library.erdc.dren.mil/jspui/ The Georgetown Harbor model, a fixed-bed model constructed to linear scale ratios of 1:800 horizontally and 1:80 vertically, reproduced a portion of the Atlantic Ocean, Winyah Bay including Mud Bay, North Inlet and marshes between Winyah Bay and North Inlet, the Sampit River including Georgetown Harbor, and the lower portions of the Pee Dee, Black, and Waccamaw Rivers and adjacent marshes. The model was equipped with necessary appurtenances for the accurate reproduction and measurement of tides, tidal currents, salinity intrusion, freshwater inflow, and shoaling distribution . The purposes of the model study were (A.) to determine the effects on the hydraulic, salinity, and shoaling characteristics of a deepening from 27 to 35 ft of the main navigation channel to Georgetown Harbor and (B.) to determine whether present maintenance dredging can be reduced by proposed plans involving channel revisions, sediment traps, and freshwater flow diversion. This report presents and analyzes the results of the testing of the following schemes : Western Channel and Turning Basin scheme (Plans 1, 1A, and 2-6), Marsh Island Channel and Turning Basin scheme (Plan 7), Upper Winyah Bay Side Channel Trap scheme (Plans 8 and 9), Inflow Diversion scheme (Plan 10), and Deepened Channel scheme (Plan 11). Western Channel and Turning Basin scheme, Plans 1 and 1A, reduced the overall annual shoaling (Western Channel plus Georgetown Harbor Channel) by 63 and 45 percent less than that for the existing channel, respectively. The effects of Plans 2, 3, 5, and 6 on shoaling when compared with Plan 1A were detrimental rather than beneficial and therefore cannot be recommended. The effects of Plan 4 on shoaling, when compared with Plan 1A, were definitely beneficial because of the much more even distribution of shoaling material along the Western Channel. Although the annual shoaling rate for Plan 4 is almost the same as that for Plan 1A, the elimination of the extremely high shoaling rate in one section (section WC3) should permit dredging to be performed on a less frequent basis. Since the overall annual shoaling rate was reduced to 43 percent of the existing rate and no unacceptably high shoaling rates occurred in any individual section, Plan 7 was an effective scheme for reducing the maintenance dredging requirements for the Georgetown Harbor project. Since the overall annual channel shoaling rate for Plans 8 and 9 was increased about 800,000-900,000 cu yd over the present shoaling rate and Georgetown Harbor (Sampit River) shoaling was reduced only about 350,000-450,000 cu yd, neither Plan 8 nor Plan 9 appears to be an effective solution to the existing maintenance dredging problem. Based on the assumption that the 90 percent reduction of the freshwater inflow to the bay would reduce the sediment supply by 90 percent, the overall annual channel shoaling rate for Plan 10 was 63 percent less than the existing rate. Plan 10 is an effective scheme for the reduction of maintenance dredging requirements for the Georgetown Harbor project. The overall annual channel shoaling rate for Plan 11 was 88 percent more than the existing shoaling rate.

Source: https://erdc-library.erdc.dren.mil/jspui/ An existing comprehensive physical model that correctly reproduced tides, tidal currents, and density currents throughout the Charleston Harbor was used to determine what quantity, if any, of effluents discharged into Cooper River would be transported from three proposed discharge points (located between miles 30 and 37 on Cooper River) to the mouth of the freshwater intake canal for the reservoir (located at mile 43) and subsequently through the intake canal into the reservoir proper. In addition to travel times of the effluents to critical locations, it was desired to determine the maximum concentrations of the effluents in Cooper River and Back River Reservoir. It was desired to know the rates of increases of effluent concentrations at critical locations should the freshwater discharge from Pinopolis reduce to zero. It was also desired to know if there would be saltwater intrusion into Back River Reservoir during operation of the Schedule C and Schedule E hydrographs. Based on the results of the model tests, the following conclusions were reached : (A.) For the Schedule C hydrograph and continuous dye release at Cooper River mile 37 (sta 37C) , measurable concentrations reached the Back River Reservoir (sta BR1) within four tidal cycles after the release (Test 1). (B.) For the Schedule C hydrograph and the dye released at Cooper River mile 37 (sta 37C) at the rate of 30 cfs during each ebb phase of the tide and 0 cfs during each flood phase, measurable dye concentrations reached the Back River Reservoir (sta BR1) within four tidal cycles after the release (Test 2). (C.) For the Schedule C hydrograph and continuous dye release at Cooper River mile 33 (sta 33C) , measurable dye concentrations reached the Back River Reservoir (sta BR1) within five tidal cycles after the release (Test 3). (D.) For the Schedule C hydrograph and continuous dye released at Cooper River mile 33 (sta 33C) at the rate of 30 cfs during each ebb phase of the tide and 0 cfs during each flood phase, measurable dye concentrations reached the Back River Reservoir (sta BR1) within five tidal cycles after the release (Test 4). (E.) For the Schedule C hydrograph and continuous dye release at Cooper River mile 30 (sta 30C), measurable dye concentrations reached the Back River Reservoir (sta BR1) within 25 tidal cycles after the release (Test 5). During the period of zero flow (cycles 56-68), dye moved into the Back River Reservoir with maximum concentrations of about 0.09 to 0.13 percent of initial concentration. After resuming the Schedule C hydrograph, the dye was flushed from sta BR1 with about 0.02 to 0.05 percent still remaining at sta BR2, BR3, and BR4 when the test was terminated. (F.) For the Schedule E hydrograph and continuous dye release at Cooper River mile 37 (sta 37C) , measurable dye concentrations reached the Back River Reservoir (sta BR1) within three tidal cycles after the release (Test 6). (G.) For the Schedule C hydrograph, maximum salinities in the Back River Reservoir varied from 15 ppm total salt at sta BR1 to 46 ppm at sta BR2. For the Schedule E hydrograph, the maximum salinities varied from 10 ppm at sta BR1 to 15 ppm at sta BR2 and BR3. (H.) The upstream limit of intrusion (100 ppm) of ocean salt water (high-water slack, bottom) was approximately Cooper River mile 43 (sta 43C) for Schedule C and approximately Cooper River mile 41 (sta 41C) for Schedule E.

Source: https://erdc-library.erdc.dren.mil/jspui/ The Mobile Bay model was a fixed-bed model constructed to linear scale ratios of 1:1000 horizontally and 1:100 vertically. As shown in Plate 1, the model reproduced about 268 square miles of the Gulf of Mexico from Pine Beach on the east to about the west end of Dauphin Island, and in a southerly direction to about the -70-ft contour in the Gulf; all of Mobile and Bon Secour Bays; a portion of Mississippi Sound; and the Mobile and Tensaw Rivers and adjacent marshes to the junction of the two rivers at Mt . Vernon, some 40 miles upstream from Mobile. The model was equipped with the necessary appurtenances for accurate reproduction and measurement of tides, tidal currents, salinities, freshwater inflows, density effects, and other important prototype phenomena. The purpose of the model study was to determine the impact of a proposed access channel, referred to as Theodore Ship Channel, and the necessary islands designed to hold the initial construction material and subsequent maintenance dredging on salinities and flow patterns with special interest centered on the oyster industry at the lower end of Mobile Bay. The Theodore Ship Channel connects the existing bay navigation channel and the Theodore Industrial area. Verification tests were conducted to make certain that the model hydraulic and salinity regimens agreed with those of the prototype. The agreements attained between similar model and prototype values were considered satisfactory. The test results consist of comparable measurements of tide heights, current velocities, salinities, surface current patterns, and dye dispersion patterns for existing and proposed conditions. There were nine suggested configurations for the disposal areas, and an abbreviated testing program was first conducted to select the best configuration for complete testing. An analysis of the results of the bottom salinity comparisons of the abbreviated model tests led to the conclusion that for disposal areas west of the main navigation channel, plan 1B was best, closely followed by plan 1D. For plans east of the channel, plan 1G was best. The results of the abbreviated testing program, furnished the Mobile District in preliminary form, and a rating system, incorporating many parameters, such as navigation, economics, environmental effects, aesthetics, and others as reported in Appendix A, were considered. The analysis by the U. S. Army Engineer District, Mobile, indicated disposal island plan 1D to be the most desirable; therefore, this plan was subjected to the formal testing program, along with a modification of plan 1G, in order to have complete results for one plan located on each side of the main bay navigation channel. After the original study had been completed, the Mobile District requested that additional studies be conducted for another disposal area arrangement, designated as plan 1E (modified). The results of those studies are included in Appendix B. Appendixes C and D, which present dye time-concentration curves for plan 1D and plans 1E and 1G (modified), are published under separate cover in limited quantity. Copies are available upon request from the Hydraulics Laboratory, U.S. Army Engineer Waterways Experiment Station._x000D_ _x000D_ NOTE: This file is large. Allow your browser several minutes to download the file.

Source: https://erdc-library.erdc.dren.mil/jspui/ Hurricane protection barriers are proposed for the Galveston Bay area. A separate model indicated that two barrier schemes would protect upstream areas : the plan 2 Alpha barrier was located just behind the gulf beaches and the plan 2 Gamma barrier crossed Galveston Bay 9 miles upstream. Both schemes provide gated navigation openings across channels and gated tidal passages of sufficient capacity, located to maintain existing conditions with respect to tides, currents, salinities, and dispersion patterns. Gated tidal passages are expensive and should be held to a minimum. Tests for normal tides were made in a 1:600-, 1:60-scale model for pre- and post-barrier conditions, and tides, currents, salinities, and dispersion patterns were observed. Important conclusions were : (A.) the plan 2 Alpha barrier would have no significant effects on tides, currents, salinities, or dye dispersion patterns; (B.) maximum current velocities in the navigation opening of the plan 2 Alpha barrier would be about 5.2 fps for normal tide; (C.) the plan 2 Gamma barrier would cause slight reductions in the tidal prism and salinities upstream of the barrier.

Source: https://erdc-library.erdc.dren.mil/jspui/ 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 mlw. 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 horizon tally 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, if modified to include a larger rehandling basin but without extension of the Federal Jetty, would meet all requirements for a combination scheme to stabilize the entrance channel and permit bypassing sand to downdrift beaches by means of conventional dredging plant. 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._x000D_ _x000D_ NOTE: This file is large. Allow your browser several minutes to download the file.

Source: https://erdc-library.erdc.dren.mil/jspui/ The Houston Ship Channel model, a fixed-bed model constructed to linear scale ratios of 1:600 horizontally and 1:60 vertically, reproduced a portion of the Gulf of Mexico adjacent to the Galveston Harbor Entrance, the Galveston Bay complex, including Trinity Bay in its entirety, East Bay, a portion of West Bay, the Houston Ship Channel to its upstream boundary in the City of Houston, Texas, and Buffalo Bayou from the Houston Ship Channel turning basin to the confluence of White Oak Bayou. The model was equipped with necessary appurtenances for the accurate reproduction and measurement of tides, tidal currents, salinity intrusion, freshwater inflow, density effects, shoaling, and other important prototype phenomena. The purpose of the model study was to determine if the present cost of maintenance dredging can be reduced by proposed plans involving channel realignments, partial or complete diking of connecting bays, sediment traps, dikes in Galveston Bay, local contractions, enlargements, and other remedial measures. Model verification tests were conducted to make ceriain that the model hydraulic and salinity regimens were in satisfactory agreement with those of the prototype. The agreements attained between similar model and prototype values were considered satisfactory.

Source: https://erdc-library.erdc.dren.mil/jspui/ Migration from cities to suburban areas combined with industrial growth justifies hurricane protection for the Galveston Bay area. A separate model indicated two barrier schemes would protect upstream areas. Alpha barrier was located just behind the gulf beaches and Gamma barrier crossed Galveston Bay 9 miles upstream. Both schemes provide gated navigation openings across channels and gated tidal passages of sufficient capacity, located to maintain existing conditions with respect to tides , currents, salinities, and dispersion patterns. Gated tidal passages are expensive and should be held to a minimum. Diversion of Trinity River flow to Houston, which would increase fresh water to Buffalo Bayou and decrease fresh water to Trinity Bay, is proposed. A power station will pump up to 3500 cfs of cooling water from Houston Ship Channel and Tabbs Bay via Cedar Bayou to the plant and discharge into Trinity Bay. Conservation agencies questioned the effects of these diversions on salinities and dispersion patterns. Tests for normal tides were made in a 1:600-, 1:60-scale model for pre- and post-barrier and pre- and post-diversion conditions, and tides , currents , salinities , and dispersion patterns were observed. Important conclusions were : (a.) diversions from Trinity River to Houston, planned for 1980, will have no significant effects; (b.) Cedar Bayou Power Station will transport more saline and poorer quality water from Houston Ship Channel and Tabbs Bay to upper Trinity Bay; (c.) plan 1 Alpha barrier would have no significant effects on tides, currents, salinities, or dye dispersion patterns and the area of tidal passages could be reduced 20 percent without adversely affecting navigation; (d.) plan 1 Gamma barrier would cause slight reductions in tidal prism and salinities; and (e.) additional tests of revised Alpha and Gamma plans are indicated._x000D_ _x000D_ NOTE: This file is large. Allow your browser several minutes to download the file.

Source: https://erdc-library.erdc.dren.mil/jspui/ The existing comprehensive fixed-bed model of James River was used to determine the effects of the proposed westward extension of the present Craney Island dike on surface flow patterns, velocities adjacent to the levees, salinities in the adjacent flats, and tidal heights. The test results consist of comparable measurements of tide heights, current velocities, and salinities for existing and proposed conditions. An analysis of the results of the model tests led to the conclusions that the proposed westward extension of the present Craney Island disposal area using either of two dike alignments tested would have no significant effects on local current velocities, salinities, or tidal heights. Also, the spoil area expansion would have minimal and insignificant effects on other factors influencing the local environment, with the obvious exception that the portion of the river bottom within the limits of the proposed disposal area expansion would be removed.

Source: https://erdc-library.erdc.dren.mil/jspui/ The existing comprehensive fixed-bed model of James River was used to determine the effects of the proposed Elizabeth River dike on tides, currents, salinities, and shoaling in the Elizabeth River channel. The test results consist of measurements of tide heights, current velocities, salinities, and shoaling quantities. From these data it was concluded that the proposed dike had little effect on tides, currents, or salinities in the problem area. In the model, the major source of sediment moving to and depositing in the Elizabeth River channel was found to be the shallow-water area between the Craney Island disposal area and the Newport News Channel. If this area does, in fact, constitute the major source of Elizabeth River channel shoaling in the prototype, the annual shoaling rate in the channel will be greatly reduced by construction of the dike; and the shoaling in the slips will be increased slightly. It is recommended that consideration be given to radioisotope or other tracer techniques to determine the source of shoaling in the Elizabeth River channel, provided an analysis of benefits and costs indicates that construction of the dike would be economically feasible.