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A large physical model replicating approximately 19 miles of Cook Inlet was constructed at ERDC with a horizontal length scale of 800-to-1 and a vertical length scale of 200-to-1. The model included the Knik Arm, a portion of Eagle Bay, and a region south of Point Woronzof. The Port of Anchorage is located in the Knik Arm, and tidal flows at the Port generated by the +30-ft tide range are highly influenced by a large gyre that forms to the south of Cairn Point during ebb tide. The purpose of the physical model was to evaluate changes to tidal flows caused by a large, multi-phased Port expansion that might impact the Alaska District's navigation mission at the Port. Model validation consisted of reasonable reproduction of field-measured tidal velocities collected at three locations near the Port over the spring tide cycle. Velocity measurements over a tide cycle were acquired in the model at strategic locations near the Port berthing areas for each phase of the Port expansion. Comparisons between the different expansion phases quantified expected changes to the flow regime. Potential sedimentation problems were identified using both measurements and flow visualization techniques coupled with time-lapse video.

A 1-to-75 scale physical model of Sitka, Alaska, encompassing portions of the Western Channel, the region protected by the three breakwaters, New Thomsen Harbor, and the Sitka and Japonski Island shorelines, was constructed at the modeling facilities of the U.S. Army Engineer Research and Development Center's Coastal and Hydraulics Laboratory. The primary objectives of the physical model study were to (1) establish the cause for wave action within the harbor causing vertical motion of the floating docks and (2) investigate potential engineering alternatives to reduce wave action within the harbor to acceptable levels. A total of 179 tests were conducted in the Sitka physical model during four time periods between the completion of the model in September 2005 and February 2007. Several hypotheses explaining increased wave action in New Thomsen Harbor were tested. Of these hypotheses, wave focusing by local bathymetry near New Thomsen Harbor appeared to be the most plausible; incident waves interacting with waves reflected by the shoreline at high water were a possible contributor for longer period waves. Large, short-period waves from the northwest could cause high waves in the harbor, but only when the wind blows hard from that direction. Distance between the rubble-mound breakwaters and harbor is also adequate to generate sizable short-period waves within the harbor. The short-wave energy could excite a harmonic frequency of the dock system resulting in adverse motions. At present the floating dock harmonics are unknown. Closing one or more gaps between adjacent breakwaters and/or breakwaters and the shoreline reduced wave heights in New Thomsen Harbor. Leaving only one gap open when waves came from the southwest reduced wave heights by about half. Closing only one gap while leaving the rest open did not create an appreciable wave height reduction when waves came from the southwest., The original document contains color images.

At the request of the U.S. Army Engineer District, Honolulu, a coastal physical model investigation of Maalaea Harbor was conducted. Purposes of this investigation included: (a) evaluating various structural alternatives for reducing wave heights within the harbor, (b) improving navigation conditions at the harbor entrance, and (c) evaluating the effects of the various alternatives on the surfing sites which is believed to be a first for this type of investigation. Based on results of the coastal model investigation, comparisons with prototype wave data and videos of prototype waves, and opinions of visitors familiar with local surfing conditions at Maalaea Harbor, it is concluded that: (a) the model replicated both the waves that comprise the Maalaea Pipeline and the unacceptably high wave conditions that presently exist within the harbor, and (b) based on the exhaustive wave data presented herein, observations by model operators with extensive experience and observations of visitors familiar with the Maalaea Pipeline, it was concluded that none of the alternatives investigated herein should have a measurable effect on the Maalaea Pipeline.

A 1:75-scale (undistorted) three-dimensional coastal hydraulic model was used to investigate the design of proposed improvements for enhancement of wave-induced circulation at Kaunakakai Harbor, Molokai, HI. The model reproduced approximately 2,010 m (6,600 ft) of the Molokai shoreline, the existing causeway and harbors, and sufficient offshore bathymetry in the Pacific Ocean to permit generation of the required experimental waves. A 21.3-rn-long (70-ft-long) spectral wave generator, an automated data acquisition system, and a crushed coal tracer material were utilized in model operation. It was concluded from study results that: a) For existing conditions, wave height experiments indicated that wave heights of 0.46 m (1.5 ft) in the small-boat harbor and 0.27 m (0.9 ft) in the deep-draft port will occur for storm waves generated in deep water, and b) For existing conditions, wave height experiments and visual observations indicated that wave conditions east of the causeway were greater for locally-generated wind waves (due to wave growth over the shallow reef) than for the larger waves generated in deep water since they broke and expended their energy on the edge of the reef.

A 1:10-scale (undistorted) three-dimensional coastal hydraulic model was initially 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 submerged reefs were investigated. Proposed improvements consisted of deepening the entrance channel, constructing a maneuvering area and installing a wave dissipating landfill inside the existing harbor, and constructing submerged reels seaward of the main breakwater. The model was reactivated in 1997 to study, on a preliminary basis, small-boat harbor improvements and flushing of Salt Lagoon in St Paul Harbor. In this study, the model was reactivated to finalize the design of small-boat harbor improvements and flushing at St. Paul Harbor. The model reproduced approximately 2,865 m (9,400 ft) of the St Paul shoreline, the existing harbor, the surface area of Salt Lagoon with its connecting channel to the harbor, and sufficient offshore area in the Bering Sea to permit generation of the required test waves. An 18.3-m-long (60-ft-long) unidirectional, spectral wave generator and an automated data acquisition and control system were used in model operation. Conclusions from study results were as follows: (a) Preliminary experiments indicated that all improvement plans would result in wave heights of less than 0.3 m (1.0-ft) in the small-boat mooring area for short-period storm wave conditions. (b) Preliminary experiments indicated that the harbor would experience long-period (surge) conditions for all the improvement plans.

A 1:90-scale (undistorted) three dimensional coastal hydraulic model was used to investigate the design of proposed navigation improvements at Nome Harbor, Alaska, with respect to wave, current, and shoaling conditions at the site. The model reproduced about 3,350 m (11,000 ft) of the Alaskan shoreline, the existing harbor and lower reaches of the Snake River, and sufficient offshore bathymetry in the Norton Sound to permit generation of the required experimental waves. The model was used to determine the impacts of a new entrance channel on wave-induced current patterns and magnitudes, sediment transport patterns, and wave conditions in the new channel and harbor area, as well as to optimize the lengths and alignments of new breakwaters and causeway extensions. A 24.4-m-long (9O-ft-1ong) unidirectional, spectral wave generator, and automated data acquisition and control system, and a crushed coal tracer material were utilized in model operation. It was concluded from study results that: a) existing conditions are characterized by rough and turbulent wave conditions in the existing entrance. Very confused wave patterns were observed in the entrance due to wave energy reflected off the vertical walls lining the entrance. Wave heights in excess of 1.5 m (5 ft) were obtained in the entrance for typical storm conditions; and wave heights of almost 3.7 m (12 ft) were obtained in the entrance for 5O-year storm wave conditions with extreme high-water level (4 m (+13 ft); b) wave conditions along the vertical-faced causeway docks were excessive for existing conditions. Wave heights in excess of 3.7 and 2.7 m (12 and 9 ft) were obtained along the outer and inner docks, respectively, for typical storm conditions; and wave heights of almost 7 and 5.8 m (23 and 19 ft) were recorded along these docks, respectively, for 5-year storm wave conditions with extreme high-water levels.

A 1:10-scale (undistorted) three-dimensional coastal hydraulic model was initially 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 were investigated. 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. In this study, the model was reactivated to optimize flushing of Salt Lagoon and small-boat harbor improvements in St. Paul Harbor. 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. An 18.3m-long (60ft-long) unidirectional, spectral wave generator, an automated data acquisition and control system, and a crushed coal tracer material were used in model operation.

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. A 24.4m-long (80-ft-long) unidirectional, spectral wave generator, an automated data acquisition and control system, a water circulation system, and a crushed coal tracer material were used in model operation.

A 1:75-scale undistorted hydraulic model was used to evaluate the effectiveness of a proposed segmented reef structure, oriented lakeward of the existing Burns Waterway Harbor breakwater, in reducing wave heights reaching the existing breakwaters. The model reproduced bathymetry 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. (MM)

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: (1) 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; and (2) 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

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 electrohydraulic, unidirectional, spectral wave generator and an automated data acquisition and control system were used in model operation.

A 1:100 scale (undistorted) hydraulic model of Los Angeles Outer Harbor, California, was used to investigate short-period storm and subsequent 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 generation of the existing breakwaters, and sufficient bathymetry in San Pedro Bay to permit generation of 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 harbor's complex) if the adjacent Port of Long Beach and/or the Pactex landfills are not constructed initially. A 80-ft-long electro-hydraulic, unidirectional, spectral wave generator and an automated data acquisition and control system were used in model operation.

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. (jg)

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. It was concluded from test results that sediment transport at Surfside-Sunset Beach to the northwest for test from south and south- southwest, and movement to the southeast for test waves southwest and west- southwest.

A 1:75-scale undistorted hydraulic model was used to determine both short- and long- period wave conditions and river flow conditions in Noyo River and Harbor as a result of various breakwater configurations at the entrance. The model reproduced the river from its mouth to point approximately 15,000 ft upstream, both Noyo Harbor and Dolphin Marina located on the south bank, approximately 3,500 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. Some improvement plans included the use of dolosse armor units for breakwaters constructed in Noyo Cove seaward of the river entrance. A 45-ft long wave generator, crushed coal sediment tracer material, and an automated data acquisition and control system were utilized in model operation.

A 1:75-scale (undistorted) hydraulic model of a proposed ocean entrance at Bolsa Bay, California, was used to investigate wave conditions in the entrance and interior basins of the proposed marina and sediment patterns along the coast as a result of the proposed jetties and breakwater. The model reproduced approximately 8,000 ft of the California shoreline, the proposed interior basins of the marina complex, a portion of the Wintersburg Flood- Control Channel, and sufficient offshore bathymetry in the Pacific Ocean to permit generation of the required test waves. An 80-ft-long unidirectional, spectral wave generator, an automated data acquisition system, a circulation system to generate steady-state flood and ebb tidal flows, and a crushed coal tracer material were utilized in model operation. It was concluded from test results that the originally proposed improvement plan with the navigable ocean entrance and connector channel to proposed improvement plan with the navigable ocean entrance and connector channel to Huntington Harbor will not meet the established wave height criteria in the interior basins unless revetments along the interior channels and a 300-ft-long spur across the opening of the northwest basin are installed, in conjunction with raising the crest elevation of a 900- ft-long portion of the offshore breakwater from +18 to +22 ft. The lengths of the north and south wings of the offshore breakwater were adequate to prevent the movement of sediment into the entrances of the marina. It was also determined that discharges from Wintersburg Channel should have minimal impacts in the interior channels and basins of the marina complex.

Tests were conducted in an existing 1:100-scale model of Mission Bay Harbor to determine the location and orientation of proposed structures for improving hazardous entrance conditions and reducing surge inside the harbor while minimizing impacts on surfing. The model reproduced Mission Bay Harbor, approximately 3 miles of adjacent Pacific Ocean shoreline, and sufficient offshore bathymetry to permit generation of the required test waves. Two wave generators (60 and 70 ft long), special photographic techniques, and an automated data acquisition and control system were utilized during model operation.

A 1:100-scale (undistorted) hydraulic model of the western portion of Cleveland Harbor, which was used initially to determine effects of proposed improvements at Cleveland Harbor main entrance with respect to ship maneuverability, wave and current action, and riverflow conditions was used to determine the effects of various improvement plans with respect to wave and current action at Edgewater Marina, located at the western boundary of Cleveland Harbor. Improvements at Edgewater Marina consisted of modifications to the harbor entrance and channel, installation of new breakwaters, modifications to the existing structures, and installation of rubble absorbers in the harbor. A 120-ft-long wave generator and an Automated Data Acquisition and Control System were utilized in model operation.