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Source: https://erdc-library.erdc.dren.mil/jspui/ Selected coastal navigation structures are periodically monitored under the Periodic Inspections work unit of the Monitoring Completed Coastal Projects research program. Such monitoring is done to gain an understanding of the long-term structural response of unique structures to their environment. Periodic data sets are used to improve knowledge in design, construction, and maintenance of both existing and proposed coastal navigation projects. The Nawiliwili Harbor breakwater, Hawaii, was nominated for periodic monitoring by the U.S. Army Engineer Division, Pacific Ocean. The objective of the monitoring effort was to establish base level data upon which long-term stability response of the Nawiliwili breakwater could be defined through periodic inspections. The concrete armor units on the outer portion of the breakwater were monitored. The monitoring plan consisted of targeting and ground surveys, aerial photography, photogrammetric analysis of armor units above the waterline, and ground-based broken armor unit surveys. The Nawiliwili site will be revisited in the future to gather data for assessing the long-term response of the structure to its environment. These data will facilitate engineering decisions concerning whether or not closer surveillance and/or repair of the structure might be required to reduce its chances of failing catastrophically. The periodic inspection methods developed and validated for the Nawiliwili breakwater may also be used to gain insight into other Corps structures.

Source: https://erdc-library.erdc.dren.mil/jspui/ A 1:60 scale (undistorted) three-dimensional hydraulic model was used to investigate the design of proposed breakwater modifications at Newport North Marina, Yaquina Bay, OR, with respect to wave and current conditions in the harbor and sediment patterns at the site. The model reproduced the existing marina and a portion of the Yaquina River from west of the U.S. Highway 101 bridge upstream. Proposed improvements consisted of breakwater modifications at the marina entrance. A 12.2-m-long (40-ft-long) unidirectional, spectral wave generator, a water circulation system, an automated data acquisition and control system, and a crushed coal tracer material were used in model operation. Test results led to the following conclusions: (a.) Existing conditions are characterized by rough and turbulent wave conditions during periods of storm wave attack. Wave heights in excess of 0.9 m (3 ft) occurred in the marina mooring areas. (b.) Preliminary tests for the three originally proposed design alternatives (Plans 1-3) indicated that none of the test plans would meet the original 0.3-m (1-ft) criterion in the marina mooring area. (c.) Of the three originally proposed design alternatives, preliminary tests indicated that the angled rubble-mound breakwater extension concept (Plan 3 series) was most effective considering wave protection provided in the mooring area versus structure length. The detached breakwater concept (Plan 2 series) proved to be the least effective. (d.) Preliminary testing of the expeditiously constructed breakwater plans proved valuable in the selection of the structure alignments and locations used for the final test series. (e.) Test results for "modified" existing conditions (revetment, etc., installed) revealed rough and turbulent wave conditions in the marina with wave heights in excess of 0.9 m (3ft) during storm wave conditions. Generally, however, the revetment slightly improved overall wave conditions in the marina. (f.) Tests conducted in the model, in which overtopping of the existing timber breakwater was prevented, revealed that wave overtopping is not a significant problem with respect to excessive wave conditions in newport North Marina. (g.) Results of wave height tests for the final 12 test plans revealed that only Plan 6C (77.7-m-long (255 ft-long) rubble-mound breakwater extension and cumulative 67.1-m (220-ft) length of vertical structures) met the originally established 0.3-m (1 -ft) wave height criterion in the marina mooring areas. (h.) After an assessment of economic benefits, Plan 5 (54.9-m-long (180-ft-long) rubble-mound breakwater extension) was selected as the most cost-effective plan considering wave protection provided the marina mooring areas versus construction costs. (i.) Construction of the Plan 5 rubble-mound breakwater extension will have minimal impact on circulation patterns and magnitudes in the marina. (j.) Construction of the Plan 5 rubble-mound breakwater extension will have no adverse impacts on sedimentation in the marina entrance. (k.) Construction of the Plan 5 rubble-mound breakwater extension will have no adverse impacts on wave conditions along the existing docks and wharves west of the existing entrance.

Source: https://erdc-library.erdc.dren.mil/jspui/ A 1: 100-scale (undistorted) three-dimensional coastal hydraulic model was used to investigate the design of proposed harbor improvements at St. Paul Harbor, St. Paul Island, Alaska, with respect to wave and current conditions in the harbor and sediment patterns at the site. Wave-induced circulation and sediment patterns seaward of the main breakwater as a result of a submerged reef also were investigated. The model reproduced approximately 2,865 m (9,400 ft) of the St. Paul Island shoreline, the existing harbor, the surface area of Salt Lagoon with its connecting channels to the harbor, and sufficient offshore area in the Bering Sea to permit generation of the required test waves. Proposed improvements consisted of deepening the entrance channel, constructing a maneuvering area and installing a wave dissipating spending beach inside the existing harbor, and constructing a submerged reef seaward of the main breakwater. An 18.3-m-long (60-ft-long) unidirectional, spectral wave generator, an automated data acquisition and control system, and a crushed coal tracer material were used in model operation. United States. Army. Corps of Engineers. Alaska District.

Source: https://erdc-library.erdc.dren.mil/jspui/ Under the Periodic Inspections Work Unit of the Monitoring Completed Coastal Projects Prograrn, base level condi- tions have been established for the above-water arrnor stone on the Bums Harbor North Breakwater. Tue positions of arrnor stone over the 1,414-m ( 4,640-ft) length of the breakwater have been defined through lirnited ground surveys, aerial photography, and photograrnrnetric analysis. Contour maps of the breakwater as weil as cross sections of the structure have been developed. In addition, a database of broken arrnor stones has been established. Tue site will be revisited periodically in the future and the long-term structural response of the breakwater to its environrnent will be tracked. Tue periodic data sets will be used to improve knowledge in design, construction, and maintenance of the ex- isting structure as weil as proposed future coastal projects.

Source: https://erdc-library.erdc.dren.mil/jspui/ Under the Periodic Inspections work unit of the Monitoring Completed Coastal Projects Program, precise locations of dolos armor units on the Manasquan Inlet, New Jersey, jetty heads were established and compared with data obtained previously. The vertical and horizontal positions of the dolos were defined through limited ground surveys, low-altitude aerial photography, and photogrammetric analysis. Broken dolos armor units also were documented. Even though horizontal and vertical movements have occurred, the jetties appear to be in good structural condition and are functioning as intended. There are areas at the heads of each structure that require additional dolosse to maintain the design cross section. The site will be revisited periodically in the future and the long-term response of the breakwater to its environment will be tracked. These periodic data sets are used to improve knowledge in design, construction, and maintenance of the existing structure as well as proposed future coastal projects.

Source: https://erdc-library.erdc.dren.mil/jspui/ A 1:75-scale undistorted hydraulic model was used to evaluate the effectiveness of a proposed segmented reef structure, oriented lakeward of the existing Bums Waterway Harbor breakwater, in reducing wave heights reaching the existing breakwaters. The model reproduced bathymeby which extended to an offshore depth of -46 ft in Lake Michigan, and the proposed reef breakwater was located in water depths ranging from -39 to -41 ft. The total area reproduced in the model was approximately 12,000 sq ft, representing about 3.7 square miles in the prototype. An 80-ft-long electrohydraulic, spectral wave generator and an Automated Data Acquisition and Control System were utilized in model operation. It was concluded from the model investigation that (a) the originally proposed reef breakwater plan (Plan 1) will result in excessive wave conditions (in excess of the established 15.0-ft wave height criterion) for 11.6-sec, 19.5-ft incident waves from 0 deg on the leeward side of the proposed reef breakwaters, regardless of its distance from the existing structure, (b) the shoreward toe of the reef breakwater should be located 75-ft lakeward of the existing breakwater's lakeward toe (This distance provides greater wave protection, with less stone volumes, than the other distances tested), (c) of the reef breakwater configurations tested with the 75-ft crest widths, Plan 4 (275-ft-long reef segments with three westernmost openings closed) was acceptableconsidering wave heights obtained in the lee of the structure for 11.6-sec, 19.5-ft incident waves from 0 deg, (d) the 75-ft-wide crest of the Plan 4 reef breakwater configuration can be reduced to 70 ft in width (Plan 5) and still provide acceptable wave protection in the lee of the structure for 11.6-sec, 19.5-ft incident wave conditions from 0 deg, (e) the Plan 5 reef configuration (275-ft-long reef segments with three westemmost openings closed and 70-ft crest widths) will result in acceptable wave heights in the existing harbor for 7- to 11.6-sec, 5-ft and 11.6-sec, 13-ft incident wave conditions, (f) considering wave protection provided in the lee of the reef breakwater and in the existing harbor for various incident wave conditions versus volume of construction materials required, the Plan 4 reef breakwater configuration was selected as optimum, based on the plans tested, and (g) the optimum reef breakwater configuration, in conjunction with the existing breakwater (Plan 6), will have no adverse impacts on wave-induced current patterns and/or magnitudes lakeward of the existing structure.

Source: https://erdc-library.erdc.dren.mil/jspui/ A 1 :75-scale (undistorted) three-dimensional hydraulic model was used to investigate the design of proposed breakwater modifications at Rochester Harbor, New York, with respect to wave action at the site. The model reproduced approximately 1,372 m (4,500 ft) of the lower reaches of the Genesee River, the jettied entrance, about 914 m (3,000 ft) of the New York shoreline on each side of the harbor entrance, and sufficient offshore area of Lake Ontario to permit generation of the required test waves. Proposed improvements consisted of a detached breakwater with the entrance oriented to the west, a dogleg breakwater with the entrance oriented to the east, and rubble absorbers and/or spurs installed along the insides of the existing jetties.

Source: https://erdc-library.erdc.dren.mil/jspui/ A 1:100-scale (undistorted) three-dimensional hydraulic model was used to investigate the effects of proposed modifications at Camp Ellis Beach, Saco Bay, ME, with regard to shoreline erosion at the site. The model reproduced about 2,438 m (8,000 ft) of the Maine shoreline, Camp Ellis Beach, the Saco River entrance, and sufficient offshore area in the Atlantic Ocean to permit generation of the required test waves. Proposed improvements consisted of roughening a portion of the existing Saco River north breakwater; installation of a sandfill, offshore berms, and spur jetties; and the removal of the existing north breakwater. Historical tests also were performed to aid in understanding formative processes at the site. A 24.4-m (80-ft-long) unidirectional, spectral wave generator, an automated data acquisition and control system, and a crushed coal tracer material were used in model operation.

Source: https://erdc-library.erdc.dren.mil/jspui/ Under the Periodic Inspections work unit of the Monitoring Completed Coastal Projects Program. base level conditions have been established for above-water armor units on portions of the Cleveland Harbor East Breakwater. The vertical and horizontal positions of dolos and stone armor units over a cumulative 1,506 m 14,940 ft) of the breakwater have been defined through IimiteJ ground surveys, low-aititude aerial photography, and photograrnmetric analysis. A database of broken doles and stone armor units also has been established. The site will be revisited periodically in the future and the long-term structural response of the breakwater to its environment will be tracked. Theqc periodic data sets arc used to improve knowledge in design. construction. and maintenance of the existing structure as well as proposed future coastal projects.

Source: https://erdc-library.erdc.dren.mil/jspui/ A physical model study, using a 1:100 scale (undistorted) hydraulic model of Los Angeles Outer Harbor, California, was conducted to investigate short-period storm wave conditions for proposed harbor development located near the Angel's Gate entrance. The model reproduced two stages of the proposed Pier 400 dredging and landfill project, Angel's Gate entrance, portions of the existing breakwaters, and sufficient bathymetry in San Pedro Bay to permit proper reproduction of the required test waves. An 80-ft-long electrohydraulic, unidirectional, spectral wave generator and an automated data acquisition and control system were used in model operation. The following conclusions can be derived from the results of these tests: "Dredged channel configurations with no landfalls" (a.) Both the -63- and -85-ft channel configurations resulted in large wave heights at the toe of the proposed Pier 400 landfill. Maximum wave heights of 21.8 and 22.3 ft will occur for the -63- and -81-ft channels, respectively, for extreme wave conditions with a +8.0-ft still-water level (swl). The -63-ft channel bathymetry focuses wave energy slightly more to the east inside the outer harbor than the -81-ft channel bathymetry. (b.) For operational wave conditions with the +5.5-ft swl, maximum wave heights of 4.4 and 4.6 ft will occur adjacent to Pier 300 for the -63- and -81-ft channel configurations, respectively, with no landfills installed. (c.) For extreme wave conditions with the +8.0-ft swl, maximum wave heights of 10.0 and 10.4 ft will occur adjacent to Pier 300 for the -63- and -81-ft channel configurations, respectively, with no landfills installed. "Port of Los Angeles (PO LA) Stages 1 and 2" (a.) Both the POLA Stage 1 and Stage 2 landfill configurations provide excellent wave protection to the Pier 300 berthing areas. For operational wave conditions with the +5.5-ft swl, maximum wave heights will not exceed 0.4 ft; and for extreme wave conditions with the +8.0-ft swl, wave heights will not exceed 1.4 ft for either stage of construction. (b.) The berth in the channel west of Pier 400 will experience maximum wave heights of 1.0 and 1.1 ft for operational wave conditions with the +5.5-ft swl; and 3.1 and 3.7 ft for extreme wave conditions with the +8.0-ft swl for POLA Stages 1 and 2, respectively. (c.) The dredged berth east of Pier 400, included in the POLA Stage 2 configuration, will experience maximum wave heights of 2.4 ft and 3.9 ft for operational and extreme wave conditions, respectively. (d.) Overtopping of the landfill in an area approximately 1,500 to 2,000 ft west of the causeway may occur for both POLA Stages 1 and 2 for extreme test wave conditions with the +8.0-ft swl.

Source: https://erdc-library.erdc.dren.mil/jspui/ A I :75-scale undistorted hydraulic model was used to determine wave conditions at the entrance to Noyo River and Harbor as a result of an offshore breakwater. The impact of the improvements on long-period wave conditions in the harbor as well as wave induced and riverine bed-load sediment patterns was evaluated. The model reproduced the river from its mouth to a point approximately 15,000 ft upstream, both Noyo Harbor and Dolphin Marina located on the south bank, approximately 3,400 ft of the California shoreline on each side of the river mouth, Noyo Cove, and sufficient offshore area in the Pacific Ocean to permit generation of the required test waves. A 45-ft long wave generator, crushed coal sediment tracer material, and an automated data acquisition and control system were utilized in model operation. It was concluded from the model investigation that: (a.) Existing conditions are characterized by rough and turbulent wave conditions in the Noyo River entrance. Maximum wave heights ranged from 8.5 to 13.7 ft in the entrance for operational conditions (incident waves with heights of 14 ft or Jess) and from 12.2 to 15.2 ft for extreme conditions (waves up to 32ft in height) depending on incident wave direction. (b.) The offshore breakwater plan will result in maximum wave heights ranging from 6.3 to 9.3 ft in the entrance for operational wave conditions and 8. 7 to 14.6 ft for extreme conditions depending on incident wave direction. (c.) The offshore breakwater plan will not meet the 6.0-ft wave height criterion in the entrance for all incident waves of 14 ft or less (operational conditions). Based on hindcast data, however, the breakwater plan will result in the criterion being achieved 37 percent more of the time than it currently is for existing conditions when operational waves are present. The magnitude of wave heights also will be decreased by about 27 percent as a result of the offshore breakwater for operational waves. (d.) With no waves present, the offshore breakwater resulted in riverine sediment patterns similar to those obtained for existing conditions except for the 1 00-year (41,000-cfs) discharge. For this condition, the breakwater prevented material from moving as far seaward in the cove as it did for existing conditions. (e.) With waves present from west-northwest and west, the offshore breakwater slightly changes the paths of riverine sediment migration and subsequent deposits for some river discharges and does not for others. In general, considering all test conditions, riverine sediment will deposit in an area in the cove between the existing jettied entrance and the proposed structure location, both with and without the breakwater installed. (f.) The offshore breakwater will not interfere with the migration of wave-induced sediment into the cove for waves from northwest; however, for waves from southwest, the breakwater will prevent some sediment from penetrating as deeply shoreward in the cove as it did under existing conditions. (g.) The offshore breakwater plan will have no adverse impact on surge conditions due to long-period wave energy in Noyo Harbor, Dolphin Marina, and the lower reaches of the river.

Source: https://erdc-library.erdc.dren.mil/jspui/ A 1:60-scale, three-dimensional hydraulic model was used to investigate the design of a proposed harbor at Barking Sands, Kauai, Hawaii, with respect to wave action and entrance channel shoaling. The model reproduced the proposed harbor, approximately 4,600 ft of the Hawaiian shoreline, and sufficient offshore area in the Pacific Ocean to permit generation of the required test waves. One harbor configuration with two breakwater plans was tested. An 80-ft-long unidirectional, spectral wave generator, an automated data acquisition and control system, and a crushed coal tracer material were used in model operation. United States. Army. Corps of Engineers. Pacific Ocean Division. U.S. Navy Pacific Missile Range Facility.

Source: https://erdc-library.erdc.dren.mil/jspui/ Under the Monitoring Completed Coastal Projects Program, an assessment of the performance of rehabilitation of the Cleveland Harbor east breakwater was conducted. Monitoring was performed doting the period November 1980-September 1985. The monitoring program relied heavily upon the use of ground control surveys, aeria1-photography to monitor above-water dolos movement, periodic inventories of individual armor units for breakage and side-scan sonar to document underwater conditions. Non-directional prototype wave gages also were used to record the wave climate during the ice-free period at the site. Data on performance of the project, observations noted in the prototype, and results of data collection, as well as conclusions and recommendations based on the monitoring effort, are reported herein.

Source: https://erdc-library.erdc.dren.mil/jspui/ A 1:90 scale, three-dimensional hydraulic model was used to investigate the design of proposed entrance channel depth modifications at Morro Bay Harbor, California, with respect to navigation conditions. The impact that the proposed depth changes may have on wave conditions at the existing structures and the spit between the south structures also was addressed, and sediment tracer patterns were obtained in the entrance. The model reproduced the harbor entrance, approximately 7,000 ft of the California shoreline, and offshore bathymetry in the Pacific Ocean to a depth of 60 ft mean lower low water (mllw). A 60-ft-long unidirectional, spectral wave generator, an automated data acquisition system, and crushed coal tracer material were utilized in model operation. It was concluded from test results that: (a.) For the existing harbor entrance, operational waves (8 to 16 ft in height) from the predominant 275 deg direction resulted in hazardous entrance navigation conditions due to wave steepening and/ or breaking. (b.) For the originally proposed improvement plan (Plan 1), navigation conditions in the entrance were improved for operational waves from 275 deg; however, the plan resulted in significantly increased wave heights which may cause damage to the head of the south breakwater during extreme wave conditions (waves ranging from 21 to 30 ft in height). (c.) Of the improvement plans tested, the channel and sand trap configuration of Plan 14 appeared to be optimal with respect to all wave conditions from all directions. Navigation conditions in the entrance will be improved, and the plan will have no negative impact on the existing structures or the spit between the south breakwater and the groin. (d.) Sediment tracer tests indicated that sediment moving in the predominant northerly direction will deposit in the deepened entrance channel and sand trap area of Plan 14 as desired, and material moving in the southerly direction will deposit in the deepened entrance channel. (e.) The -30-ft entrance channel of Plan 15 will result in similar wave conditions for operational and extreme waves as the -40-ft channel of Plan 14, which would be acceptable with regard to entrance conditions and would have no negative impact on the breakwaters and spit area.

Source: https://erdc-library.erdc.dren.mil/jspui/ A 1:75 scale, three-dimensional hydraulic model was used to investigate the design of a proposed harbor structure and channel modifications at Oceanside Harbor, California, with respect to wave and shoaling conditions in the harbor entrance and wave conditions in the inner harbor. The model reproduced approximately 9,000 ft of the California shoreline and included portions of the existing harbor and offshore bathymetry in the Pacific Ocean to a depth of 36 ft mean lower low water (mllw). Improvement plans consisted of a seaward extension of the existing north breakwater, the installation of a spur on the south jetty, and modifications to the entrance channel. An 80-ft-long unidirectional, spectral wave generator, an automated data acquisition system, and crushed coal tracer material were utilized in model operation. It was concluded from the test results that: (a.) For the existing harbor configuration, wave heights in the inner harbor were more severe during periods when the shoal in the entrance channel was not present. With the shoaled entrance, waves broke and expended some of their energy, while with the dredged entrance (authorized depths), more wave energy propagated into the harbor. (b.) The originally proposed improvement plan (Plan 1, 180-ft-long jetty spur (el +14 ft) and 300-ft-long breakwater extension (el +18 ft)) will result in wave conditions in the inner harbor in excess of the established criteria (0.2, 0.4, and 0.6 ft for weekly, annual, and 20-yr wave conditions, respectively). (c.) Of the improvement plans tested with the jetty spur on its original alignment (Plans 1-13), only the 230-ft-long jetty spur and the 450-ft-long breakwater extension of Plan 7 met the established wave height criteria. (d.) Of the improvement plans tested with the reoriented jetty spur (Plans 14-22), only the 280-ft-long jetty spur and the 300-ft-long breakwater extension of Plan 22 met the established wave height criteria. (e.) Of all the improvement plans tested from 235 deg, and considering wave protection afforded versus volume of construction materials, the 180-ft-long jetty spur and the 250-ft-long breakwater extension of Plan 17 were considered optimal. The wave height criteria will be exceeded by 0.1 ft at only one gage location in the inner harbor for weekly and annual wave conditions. (f.) The Plan 17 harbor configuration will result in wave heights in the inner harbor that are 60 percent less, on the average, than those obtained for existing conditions (with authorized channel depths) for test waves from the more predominant 235-deg direction. (g.) Wave heights in the outer entrance will be reduced as a result of the installation of Plan 17 for test waves from the more predominant 235-deg direction. (h.) Considering test waves from the 250- and 210-deg directions, the wave height criteria in the inner harbor will be exceeded by only 0.1 ft at one gage location for weekly, annual, and/or 20-yr wave conditions when Plan 17 is in place. (i.) The installation of the Plan 17 structures should not impact sediment-patterns on a regional basis. Sediment will continue to move into the expanded entrance, but it will deposit more seaward in the entrance and will not penetrate as deeply into the entrance channel. (j·) Model results indicate that installation of Plan 17 will not have any impact on long-period wave conditions in the inner harbor basins.

Source: https://erdc-library.erdc.dren.mil/jspui/ A physical model study, using a 1:100 scale (undistorted) hydraulic model of Los Angeles Outer Harbor, California, was conducted to investigate short-period storm wave conditions for proposed harbor development located near the Angel's Gate entrance. The model reproduced the proposed harbor expansion, Angel's Gate entrance, portions of the existing breakwaters, and sufficient bathymetry in San Pedro Bay to permit proper reproduction of the required test waves. The model then was reactivated to determine the optimum plan for protection of the south mooring area from locally generated waves in the harbors complex if the adjacent Port of Long Beach and/or the Pactex landfills are not constructed initially. Finally, tests reported herein describe wave conditions in various mooring areas during phases of construction. An 80-ft-long electro-hydraulic, unidirectional, spectral wave generator and an automated data acquisition and control system were used in model operation. It was concluded from results of these tests that : (A.) As tested, the originally proposed first phase of construction (Plan 1) will result in wave heights well within the established criteria of 2.5 ft in the dry bulk terminal and 1 .5 ft in the container terminal for locally generated waves within the harbors complex. (B.) A total of 3,000 ft of breakwater length can be removed from the first phase of construction (Plan 11) and the established wave height acceptance criteria will still be met for locally generated wind waves. (C.) The Plan 11 alternative of the first phase of construction (3,000 ft of breakwater removed) will provide adequate wave protection to the berthing areas during periods of storm wave attack incident from deep water. (D.) The second phase of construction (Plan 14) will provide adequate wave protection to the berthing areas during periods of storm wave attack incident from deep water.

Source: https://erdc-library.erdc.dren.mil/jspui/ Under the Monitoring Completed Coastal Projects Program, an assessment of the Beach Erosion Control Project at Oakland Beach, Rhode Island was performed. The monitoring program extended over a 3-year period from April 1982 to April 1985. Monitoring included hydrographic and topographic surveys of the beach and nearshore area, aerial and ground photographs, wind data collection, littoral environment observations, sediment sampling, and site visits. Littoral transport, structure stability, and wind and wave analysis are evaluated and discussed. Data on the performance of the project and observations made in the prototype, as well as conclusions and recommendations based on the monitoring effort, are reported herein.

Source: https://erdc-library.erdc.dren.mil/jspui/ Under the Monitoring Completed Coastal Projects Program, an assessment of the performance of a training jetty extension at Umpqua River, Oregon, was conducted. The monitoring was performed over the period from May 1983 through May 1984. It included the collection and analyzing of current, salinity, tide, wave, and beach and channel data. Evaluation of these data is discussed in detail. Comparison of the prototype data with that of a physical hydraulic model of the Umpqua River entrance conducted in 1970 was also performed to determine its predictive capabilities. Data on the performance of the project and observations made in the prototype, as well as conclusions and recommendations based on the monitoring effort, are reported herein.

Source: https://erdc-library.erdc.dren.mil/jspui/ Under the Monitoring Completed Coastal Projects Program, an assessment of shore-connected breakwaters and channel improvements at Cattaraugus Creek Harbor, New York, was performed. Data collection for the monitoring effort occurred from mid-1983 through 1985. An evaluation of waves, structure stability, sediment transport, channel stability, and ice-jam problems due to the construction of the project is discussed in detail. Data on the performance of the project and observations made in the prototype, as well as conclusions and recommendations based on the monitoring effort, are reported herein.

Source: https://erdc-library.erdc.dren.mil/jspui/ A 1:100 scale (undistorted) hydraulic model of Los Angeles Outer Harbor, California, was used initially to investigate short-period storm wave conditions for proposed harbor development located near the Angel's Gate entrance. The model reproduced the proposed harbor expansion, Angel's Gate entrance, portions of the existing breakwaters, and sufficient bathymetry in San Pedro Bay to permit generation of the required test waves. The model was reactivated to determine the optimum plan for protection of the south mooring area (from locally generated waves in the harbors' complex) if the adjacent Port of Long Beach and/or the Pactex landfills are not constructed initially. An 80 ft-Iong electro-hydraulic, unidirectional, spectral wave generator and an automated data acquisition and control system were used in model operation.

Source: https://erdc-library.erdc.dren.mil/jspui/ A 1:75 scale, three-dimensional hydraulic model was used to investigate the design of proposed harbor structures and channel modifications at Ventura Harbor, California, with respect to wave and shoaling conditions in the harbor entrance. The model reproduced approximately 9,400 ft of the California shoreline and included portions of the existing harbor and offshore bathymetry in the Pacific Ocean to a depth of -40 ft mean lower low water (mllw). Improvement plans consisted of a seaward extension of the detached breakwater, the installation of spur groins on the north jetty, construction of a new groin south of the south jetty, and modifications to the entrance channel. An 80-ft-long unidirectional, spectral wave generator, an automated data acquisition system, and a crushed coal tracer material were used in model operation. United States. Army. Corps of Engineers. Los Angeles District.

Source: https://erdc-library.erdc.dren.mil/jspui/ A 1:75-scale three-dimensional hydraulic model was used to investigate the design of proposed modifications in various areas of Redondo Beach King Harbor. The model (originally used to develop plans for wave protection in the southern portion of the harbor in the lee of a low-crested breakwater section) reproduced approximately 8,800 ft of the California shoreline and included the existing harbor and offshore bathymetry in the Pacific Ocean to a depth of -60 ft. Improvements consisted of raising portions of the north and south breakwaters, flattening the slope of the existing north breakwater in the vicinity of an adjacent mole, and installing a spur on the inside of the north breakwater. An 80-ft long unidirectional, spectral wave generator and an automated data acquisition and control system were utilized in model operation. It was concluded from test results that (A.) For test waves from 260 deg, test results for existing conditions indicated severe overtopping of the breakwater adjacent of Mole A and subsequent flooding of the mole. The proposed improvement plan (Plan 1) with additional stone placed on a 100-ft-long section at the outer end of the Galveston seawall (Plan 1A) will minimize overtopping of the breakwater and flooding of the mole. (B.) For test waves from 240 deg, the proposed improvements (Plan 2) required modification to minimize overtopping of the breakwater and subsequent flooding of Mole A. Additional stone placed on a 150-ft-long section of the outer end of the Galveston seawall (Plan 2A) was required. The Plan 2 spur, it appeared, could be reduced in elevation (Plan 2A) and minimize wave energy reaching Mole A due to spilling waves propagating northerly over the breakwater. (C.) For test waves from 220 deg, existing conditions revealed severe overtopping of the south breakwater and Mole D with subsequent flooding of the mole and adverse wave conditions in Basin 3. The proposed improvement plans (Plans 3 and 3A) reduced wave heights in the Mole D/Basin 3 vicinity; however, overtopping of the south breakwater and Mole D still occurred, only not to as great a degree. Data obtained should aid in the design of structures proposed along the waterfront in the Mole D/Basin 3 area.

Source: https://erdc-library.erdc.dren.mil/jspui/ A 1:75 scale (undistorted) hydraulic model was used to investigate the design of proposed modifications at Surfside-Sunset Beach, California, with regard to the reduction of beach erosion at the site, The model reproduced approximately 4,600 ft of the California shoreline and included the Anaheim Bay East Jetty and offshore bathymetry in San Pedro Bay to a depth of 26 ft. Proposed improvements consisted of offshore breakwaters and a breakwater attached to the existing jetty extending in a beach-parallel direction. Waves were generated by an 80-ft-long unidirectional, spectral wave generator, and a crushed coal tracer material was used to qualitatively determine the movement of beach-fill material. United States. Army. Corps of Engineers. Los Angeles District.

Source: https://erdc-library.erdc.dren.mil/jspui/ A 1:60-scale (undistorted) hydraulic model of Olcott Harbor, New York, was used to investigate wave, current, creek flow conditions, and sediment patterns for the existing harbor configuration and various improvement plans. The model reproduced approximately 3,300 and 3,600 ft of the New York shoreline on the east and west sides of the harbor, respectively, about 3,000 ft of the lower reaches of Eighteenmile Creek, and sufficient offshore bathymetry in Lake Ontario to permit generation of the required test waves. Proposed improvements consisted of the installation of rubble-mound breakwaters and channel dredging. An 80-ft-long unidirectional, spectral wave generator, an automated data acquisition and control system, and a crushed coal tracer material were utilized in model operation. It was concluded from test results that: (a.) Existing conditions are characterized by rough and turbulent wave conditions during periods of storm-wave attack. Wave heights up to 6.5 ft will occur in the existing entrance during boating season. (b.) The first basic harbor configuration (with the proposed mooring area east of the existing entrance, Plan 1 of 23 test plan variations) resulted in wave heights well within the established criteria (3.0 ft in the proposed entrance and 1.0 ft in the proposed mooring area) for boating season wave conditions. (c.) The following modifications may be made to the detached breakwaters of the first harbor configuration and still achieve acceptable boating season wave conditions. (1c.) The east and west detached breakwaters may be reduced in elevation from +16.2 and +1S.3 ft, respectively, to el +14.S ft. (2c.) The length of the east breakwater may be reduced by 125 ft (removal from the shoreward end of the structure). (3c.) The length of the west breakwater may be reduced by 350 ft (removal of 50 ft from the lakeward end and 300 ft from the shoreward end of the structure). (d.) Based on test results, the detached east and west breakwaters of the second basic harbor configuration were reduced to el +14.5 ft and the east breakwater length was reduced by 125 ft (paragraphs cl and c2). In addition, 50 ft may be removed from the shoreward end of the west breakwater (Plan 19) and acceptable wave conditions during boating season will be achieved for the second harbor configuration (mooring areas east and west of the existing entrance). (e.) The openings between the attached and detached east and west breakwaters of the second basic harbor configuration will provide wave-induced current flow through the harbor and should enhance circulation. (f.) The construction of the proposed harbor plan will have minimal impact on water surface elevations and creek current velocities in the lower reaches of Eighteenmile Creek. (g.) The opening between the attached and detached west breakwaters (Plan 19) may result in minor shoaling in the mooring area in the western portion of the harbor for test waves from 313 and 334 deg, provided a sediment source is available. The installation of a sill between the structures (Plan 21), an extension of the attached breakwater (Plan 22), or a spur on the attached structure) Plan 23) will alleviate this shoaling. (h.) Sediment placed between the existing groins east of the harbor for Plan 19 move easterly and westerly between the structures, but will remain relatively stable and not move from one cell to another. Accumulations may occur on the western sides of each cell, however, due to the predominance of the wave directions attacking the groin field.

Source: https://erdc-library.erdc.dren.mil/jspui/ A 1:60-scale (undistorted) hydraulic model of Olcott Harbor, NY, was used to determine the effects of proposed improvements on creek temperatures and currents at Eighteenmile Creek as they entered Lake Ontario. The model (originally used to develop the optimum improvements) reproduced approximately 3,300 and 3,600 ft of the New York shoreline on the east and west sides of the harbor, respectively, about 3,000 ft of the lower reaches of Eighteenmile Creek, and sufficient offshore bathymetry in Lake Ontario to permit generation of the required test waves. Improvements consisted of the installation of rubble-mound breakwaters and channel dredging. An 80-ft-long unidirectional, spectral wave generator and a reservoir of heated water were utilized in model operation. Prototype data were obtained at Eighteenmile Creek during the spring and fall seasons of 1989. Tests then were conducted to verify the performance of the model for existing conditions, and finally, the improvement plan was tested to determine its impact on temperature and current patterns. It was concluded that trends in the model (temperatures, direction of creek plume, etc.) followed trends established in the prototype for existing conditions. With the improvement plan installed, the creek currents and temperature differences varied only slightly in the localized area of the creek mouth, and, on a regional basis, the movement of creek currents after entering the lake was similar to existing conditions. Test results, in general, indicated that the improvement plan will have minimal effects on temperatures and/or the movement of creek water into the lake or along the shorelines.