Hurricane Alicia made landfall on August 18, 1983, on the eastern end of Follets Island just west of San Luis Pass and Galveston Island. The maximum winds (198 km/hour), storm surge (390 cm), and wave energy were concentrated just east of landfall, along the western half of Galveston Island and the easternmost tip of Follets Island. In this area, the mean high waterline typically eroded 30-50 m (100-165 ft), whereas the vegetation line typically eroded 20-30 m (65-130 ft). Maximum erosion of the mean high waterline (up to 300 m) and the vegetation line (up to 100 m) occurred adjacent to San Luis Pass. A narrow band of washover sands, typically extending 20 m (60 ft) inland, was deposited along the nondeveloped portions of west Galveston Island. Because of the modification of the foredune system, these washover sediments typically extended 60-80 m (200-250 ft) inland along the developed portions of the shoreline. Erosion of the shoreline along the eastern part of Galveston Island was minor, although some washover channels formed where beach access roads cut through the dunes.

In contrast, the area west of landfall on Follett's Island experienced little shoreline erosion and virtually no washovers. This area was dominated by offshore-directed winds during the passage of the hurricane; thus, the main effect was numerous storm-surge ebb channels formed by the draining of West Bay. These channels are, on the average, 20 m (65 ft) wide, 55 m (180 ft) long, and up to 3 m (10 ft) deep; the largest channel is 40 m (130 ft) wide and 110 m (360 ft) long. These channels were initiated along low spots in the dunes (typically beach access roads) and grew landward by headward erosion until they encountered the highway, where they were partially deflected.

Much of the sand transported offshore during the storm returned to the beach within the following 6 months by progressive welding of swash bars to the foreshore to form a broad, flat berm. Since then, the patterns of shoreline accretion and erosion appear to reflect seasonal rather than long-term changes. The vegetation line had not shown any significant recovery 20 months after the storm, and complete recovery of the beach to its prehurricane position seems unlikely.

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