In 1989, after many debates, studies and proposals, the National Park Service (NPS) made the decision
to move the Cape Hatteras Lighthouse approximately one-half mile from its current location to an area less susceptible to
the ocean's influence. This was not a decision that was made lightly or without controversy. Yet it is the position of the
NPS that moving the tower is the most effective means of helping fulfill its Congressional mandate of preserving historic
structures "for the enjoyment of future generations." Nearly a decade later, the President asked Congress to fund the move
in 1999.
WHY IS THE LIGHTHOUSE IN DANGER?
The key to preserving the 1870 tower is its "floating foundation". Yellow pine timbers sit in fresh
water on compacted sand, with a brick and granite foundation on top of them. This foundation was built because pilings could
not be driven through hard sand barely 8 feet below ground level when construction began. As long as the sand surrounding
the foundation remains in place, and the timbers remain bathed by the fresh water in which they were placed in 1868, the foundation
is secure. If a storm erodes the sand or the fresh water is disturbed by salt water intrusion, the timbers will begin to rot
and the foundation will eventually fail.
Hatteras Island is a barrier island migrating westward. Since the 1930s, efforts have been made to
protect the Lighthouse from the encroaching sea. The Coast Guard installed the first sheetpile "groins" (walls built perpendicular
to the shore) to try to protect the tower. In 1936, however, they abandoned the lighthouse to the sea and moved its light
to a skeleton steel tower in Buxton Woods. 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. 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 1803, that lighthouse had been one mile from the shoreline.
NPS officials considered various long-term protection options, including more groins, an encircling
seawall, and relocation of the tower from the ocean's edge. The NPS requested the assistance of the National Academy of Sciences,
a group of scientists and engineers who advise the federal government on technical matters. The Academy's 1988 report recommended
relocation as the most cost-effective method of protection. From 1988 to 1995, the relocation option was debated and discussed,
with no funding requests made at the Congressional level or concerted fund-raising campaigns undertaken in the private sector.
As Federal budgets became leaner, the NPS worked with the Army Corps of Engineers on a short-term (10-20 year) protection
option to build a fourth groin south of the lighthouse. Officials hoped that it would protect the most vulnerable section
of the lighthouse area, and would give the NPS time to raise Federal funds for relocation. However, North Carolina Coastal
Resources Commission staff stated that it would not recommend a permit for building the fourth groin since placing any hardened
structures on the North Carolina coast is prohibited by state statutes. In 1996 NPS managers initiated a concerted effort
to begin the planning and funding process to move the Cape Hatteras Lighthouse.
MOVING THE LIGHTHOUSE
Moving great weights has become easier with the development of hydraulic technologies, and within the
last five years, three lighthouses along the New England coast have been moved to reduce the threat of collapse into the sea.
All were moved by the same basic method, and the Cape Hatteras Lighthouse may be moved in a similar fashion.
International Chimney Corporation of Buffalo, New York relocated the Southeast Lighthouse on Block
Island, Rhode Island in 1993. The Southeast Lighthouse differs in design from the Cape Hatteras Lighthouse; a keepers' quarters
is attached to the lighthouse tower. After excavating around the base of the structure to expose part of the foundation, the
engineers drilled through the foundation and inserted supporting steel beams to form a grid system. International Chimney's
Mike E. Prible describes the moving process:
Following the transfer of the lighthouse load from its foundation to the beam grid ... 38 hydraulic
lifting jacks [capable of lifting 60 tons each] were activated in unison and the entire structure was raised approximately
2 feet from its original elevation. The structure was then cribbed on oak timbers, tracks positioned below and parallel to
the main beams, and the hydraulics for the jacks rerouted to three separate zones to allow for compensation on uneven surfaces
during travel, i.e., no stress would be placed on the structure if a bump or soft spot was encountered...
Moving the Southeast Lighthouse to its new foundation was accomplished by using horizontally-mounted
hydraulic jacks that push the tower along a track system in 5-foot increments. After the tower was pushed approximately 5
feet, the jacks were retracted and reset along the grid beams. Although this is certainly not a swift method of moving a structure,
it has proven to be a safe and efficient technique.
When relocated, the Cape Hatteras Lighthouse will rest upon a new concrete pad foundation some 2,900
feet from its original location. Given the patience with which structures of this size are moved, the relocation process may
take up to three months. The relocated tower will then stand 1,600 feet from the shoreline, which is approximately the same
distance it stood from the sea when it was finished in 1870.
Only time will tell if this magnificent example of American architecture and engineering can be preserved.
Thanks to the US Park Service