In 1803, that lighthouse had been one mile from the shoreline. A severe storm in 1980 accentuated the island's westward movement washing away the foundation of the first (1803) lighthouse, which had been 600 feet south of the existing lighthouse. In the 1960s and 1970s, as the ocean continued to creep closer, various attempts to "stabilize" the coast included beach nourishment and three new groins installed north of the lighthouse. In 1936, however, they abandoned the lighthouse to the sea and moved its light to a skeleton steel tower in Buxton Woods. The Coast Guard installed the first sheetpile "groins" (walls built perpendicular to the shore) to try to protect the tower. Since the 1930s, efforts have been made to protect the Lighthouse from the encroaching sea. If a storm eroded the sand or the fresh water was disturbed by salt water intrusion, the timbers would rot and the foundation would eventually fail. As long as the sand surrounding the foundation remained in place, and the timbers remained bathed by the fresh water in which they were placed in 1868, the foundation was secure.
This foundation was built because pilings could not be driven through hard sand located barely 8 feet below ground level when construction began. Yellow pine timbers sit in fresh water on compacted sand, with a brick and granite foundation on top of them. The key to preserving the 1870 tower is its "floating foundation". By 1970, this process, which has caused the gradual westward migration of the Outer Banks for at least the past 10,000 years, left the lighthouse just 120 feet from the ocean’s edge and almost certain destruction.
Even then, however, storm-driven tides completely washed over Hatteras Island, eroding sand from the ocean side of the island and depositing it on the sound side. When completed in 1870, the Cape Hatteras lighthouse was located a safe 1,500 feet from the ocean. Why the Cape Hatteras Light Station Had to be Moved
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