A 1:75-scale undistorted hydraulic model of Port Ontario Harbor, New York, which included the lower 5,700 ft of the Salmon River, approximately 4,300 ft of shoreline on each side of the river mouth, Selkirk Lake, and sufficient offshore area in Lake Ontario to permit generation of required test waves, was used to investigate the arrangement and design of proposed improvements with respect to shoaling, wave protection, and riverflow conditions. Proposed improvement plans consisted of (a) breakwaters in Lake Ontario at the mouth of the Salmon River; (b) an entrance channel; (c) an inner channel; (d) a harbor basin; and (e) recreational facilities. A 60-ft-long wave generator, a model circulation system, crushed coal tracer material, and an automated data acquisition and control system (ADACS) were utilized in model operation.