The 1968 River and Harbor Act authorized construction of a small-boat harbor at Hamlin Beach State Park on Lake Ontario in Monroe County, New York. On the basis of experience at other locations, it was deemed advisable to conduct a hydraulic model investigation of the proposed facilities to determine the most economical breakwater arrangement consistent with the provision of satisfactory entrance conditions and adequate protection to moored boats within the harbor. The 1:64-scale model was molded in cement mortar and reproduced approximately 3000 ft of the Lake Ontario shoreline on each side of the harbor entrance, the entrance channel, the harbor (approximately 500 by 1150 ft), and sufficient underwater contoured area lakeward of the harbor to permit accurate simulation of storm wave action. A 50-ft-long wave machine and electrical wave height measuring and recording apparatus were used in model operation. It was concluded that the breakwater proposed for the west side of the entrance channel could be reduced in length by 100 ft without sacrificing the full protection desired for the entrance and inner harbor and that a reduction in length of another 100 ft would not seriously impair the desired for the entrance and inner harbor and that a reduction in length of another 100 ft would not seriously impair the desired protection. (Author).