The California Legislature decreed that the California Coastal Commission had until 1 February 1978 to identify, evaluate, and rank alternate potential Liquefied Natural Gas (LNG) Terminal sites on the California coast. Because of the Corps' experience in various aspects of such studies, the U.S. Army Engineer Waterways Experiment Station was requested by the Coastal Commission to assist, particularly in the use of existing hindcast data to evaluate possible effects of wind and waves on the docking and unloading of a LNG tanker. The effect of wind and wave climate was relatively evaluated at 26 potential LNG terminal sites along the coast of California. The analysis did not apply wave refraction theory at any of the sites, so the absolute magnitudes of the values obtained at each site are subject to refinement. The computations which were performed were optimized on a site-specific basis; i.e., they have been determined by utilizing the situations unique to that one particular location, and the results should not be extrapolated far beyond the respective site, if at all.

This Station (WES) was requested to assist in the preliminary evaluation of the wave climate at alternate potential Liquefied Natural Gas (LNG) terminal sites by applying existing hindcast wave data of a general nature to obtain estimates of the times of excessive wave conditions at the various sites. After the preliminary evaluation was completed, WES was again requested to assist by analyzing the effects of island sheltering and topographic influences on the wave climates of six offshore sites in order to provide a more refined estimate of the wave conditions existing at the potential sites. Because of the absence of a comprehensive deepwater wave hindcast data base of sufficient degree of confidence to permit estimates of the absolute magnitude of occurrences of waves of different periods and heights, the analysis conducted is a relative evaluation only and should not be interpreted as projections of actual downtime, but rather as a consistently uniform basis for comparison. When the appropriate topographic coefficients had been applied to the deepwater hindcast wave data and the resulting wave climate at the potential offshore LNG site had been obtained, it was required that the effects of this resultant wave climate be determined on four possible terminal concepts at each of the six sites. These four concepts include: (a) fixed terminal with one pier, (b) fixed terminal with two piers, (c) floating barge, and (d) deepwater mooring tower.