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The Port of Los Angles has embarked upon a program to improve wave and current conditions at Fish Harbor, Los Angeles, California. To achieve this, field measurements (both wave heights and currents) for the existing harbor were obtained and analyzed and a physical hydraulic model for short-period wave tests and numerical models for harbor oscillation and tidal circulation were used to investigate the effects of proposed harbor improvements. The proposed improvements consisted of dredging deeper channels and berthing areas to accomodate the larger, deeper draft vessels using the harbor and the creation of landfills to provide for expansion of local industry. An optimum improvement plan was developed during the physical model wave tests which met the established wave-height criteria and provided increased area for mooring small craft in the lee of the harbor breakwater. The results of the long-period prototype data analysis and numerical harbor oscillation study indicated a decrease in a long-period wave energy for this optimum plan. The tidal circulation study indicated that changes in tidal circulation characteristics were limited to the vicinity of Fish Harbor and included a slight shift in flood and ebb flow patterns due to breakwater location for the optimum plan. Tidal flushing in Fish Harbor was influenced by the optimum plan but was similar to existing conditions for successive low waters.

Two numerical models and two physical models were used to investigate the effects of proposed improvement plans with respect to shoreline erosion at Buhne Point, Humboldt Bay, California. Initially, a numerical tidal circulation model was to determine the tidal current field adjacent to Buhne Point. Maximum flood and ebb tidal currents were identified and used as test conditions for the physical models. A 1:100-scale physical model of central Humboldt Bay included the jettied entrance to the bay, approximately 18,000 lin ft of shoreline inside the bay (including Buhne Point), and underwater contours throughout the central portion of the bay and the area between the jetties. The model was used to determine the wave climate (angle of wave fronts and wave heights along these fronts) in the vicinity of Buhne Point for a series of incident wave conditions and directions (waves propagated through the Humboldt Bay entrance) and for various water levels and tidal flow conditions. A 30-ft-long wave generator, an Automated Data Acquisition and Control System (ADACS), and a model circulation system were utilized in model operation. The output conditions obtained from the 1:100-scale physical model were input into a 1:50 scale physical model of Buhne Point where the effectiveness of various structures proposed for shore protection was evaluated.

A 1:60-scale (undistorted) hydraulic model of Barcelona Harbor, New York, including approximately 7,000 ft of the New York shoreline and sufficient offshore bathymetry in Lake Erie to permit generation of the required test waves, was used to investigate the design of certain proposed improvements with respect to wave action. Proposed improvements consisted of rubble-mound breakwater extensions; rubble-mound absorbers installed along the harbor sides of the existing east and west breakwaters and the lakeward face of the city dock; rubble-mound spurs installed southerly of the lakeward heads of the existing breakwaters; and a parapet wall installed on the existing west breakwater. Two 60-ft-long wave generators and an Automated Data Acquisition and Control Systems were utilized in model operation. Initially, an optimum improvement plan was selected based on the results of wave-height tests using monochromatic waves.

A 1:75-scale undistorted hydraulic model was used to investigate the impacts of the proposed Interstate 664 bridge/tunnel project on wave conditions in Newsport News Harbor, Virginia. The model included the harbor, approximately 5600 ft of shoreline adjacent to the harbor entrance, and sufficient offshore area in Hampton Roads to permit generation of the required test waves. Various plans of improvement included the use of either rubblemound or cellular concrete breakwaters. A 50-ft-long wave generator and an automated data acquisition and control system were utilized in model operation.

A study of harbor resonance due to long-period wave excitation was conducted in the Los Angeles and Long Beach Harbors hydraulic model for Phase I of the proposed Los Angeles deep-draft dry bulk export terminal, and results were compared with resonant response for existing conditions. Proposed modifications for the deep-draft dry bulk export terminal included (a) dredging a navigation channel and maneuvering area and (b) creating a new landfill of approximately 340 acres in the Port of Los Angeles.