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Additional
Information
Cape Hatteras
Relocation Project
Background Paper -- From Bob Woody, Cape Hatteras National Seashore
SYNOPSIS
Cape Hatteras Lighthouse
December 1997
HISTORY
As early as the 1500’s, when ships depended on wind for power, mariners learned
to take advantage of ocean currents. North- and east-bound vessels followed the Gulf
Stream. South-bound ships followed the Virginia Coastal Current. In each case, ships
passed close by the Outer Banks and the treacherous Diamond and Frying Pan Shoals
of Cape Hatteras and Cape Lookout.
In 1797, Congress recognized the need for a navigational aid in the vicinity of
Diamond Shoals at Cape Hatteras, North Carolina, and authorized the erection of a
lighthouse. The first lighthouse was completed in 1803 and stood about one mile inland
from the ocean beach. It was considered less than satisfactory from the time it first
came into service, as it was only 90 feet high, and the light was inadequate. In
1854, its height was increased to 150 feet, and a First-order Fresnel lens, the best
available, was installed. However, problems with the structure persisted. Inspections
in the late 1860’s showed growing cracks in the sandstone structure, and construction
of a new lighthouse was recommended.
The second (and existing) Hatteras Lighthouse was activated in December 1870,
and the original structure was razed. The new light towered 208 feet in height and
was located 1,500 feet from the water’s edge. With its distinctive black and white
candy-cane design, it soon became a landmark of the Carolina coastline. It is the
tallest lighthouse in the United States, and has served as a primary navigational
aid for mariners rounding the treacherous Diamond Shoals. Because of its historical
importance to the region and the nation, the lighthouse and its associated station
buildings have been placed on the National Register of Historic Places.
EROSION PROBLEMS
Responding to the gradually rising sea level of the past several thousand years,
barrier island systems have migrated westward. Hatteras Island is no exception. This
migration occurs as storm-driven ocean tides wash completely over the islands, moving
sand sediments toward the sound shoreline. Because of this migration, barrier islands
are among the most unstable land masses on the face of the earth. Under these conditions,
stationary structures built on them, such as the Cape Hatteras Lighthouse, are inevitably
threatened.
In 1870, the lighthouse was situated 1,500 feet from the ocean. By 1919, the ocean
had advanced to within 300 feet of the tower and to within 100 feet by 1935. A combination
of natural changes and a number of protective measures postponed the threat for a
number of years.
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Over the years, a number of erosion control projects have been initiated at the
lighthouse site to protect the structure. They include:
1930: Nine hundred feet of interlocking steel sheet pile groins were installed
along the beach shoreline.
1930’s: The Civilian Conservation Corps, under the leadership of the National
Park Service, began building a barrier sand dune system along the entire length of
Hatteras Island. Construction of sand dunes was believed by many in the 1930’s and
1940’s to be a relatively inexpensive method of preventing overwash and resulting
water damage to any structure placed behind the dunes. Today, many scientists believe
that while the dunes may prevent ocean overwash during minor storms, the dunes do
not prevent the overall erosional process resulting from increasing sea level. The
once wide beaches along the Outer Banks have continued to narrow until in many places
little or no park land exists between the ocean and structures built on land once
"protected" by an apparently solid vegetative stabilized dune.
1933: Additional sheet pile groins were installed.
1936: The U. S. Coast Guard abandoned the lighthouse and transferred ownership
to the National Park Service. A steel skeleton tower was built in Buxton Woods, one
mile west, to assume the function of the threatened lighthouse.
1950: The shoreline erosion problem appeared to have stabilized, and the Cape
Hatteras Lighthouse was reactivated by the Coast Guard under special use permit from
the National Park Service.
1966: Three hundred and twelve thousand cubic yards of sand were pumped from Pamlico
Sound onto the beach in front of the Buxton lighthouse area. Because sand from the
sounds is of much finer particles, the ocean soon eroded it away.
1967: Large nylon sand-filled bags were placed in front of the lighthouse to slow
erosion. A few of the bags remain today.
1969: The U. S. Navy built three reinforced concrete groins to protect the Naval
Facility and lighthouse. They were partially destroyed by storms and repaired with
sheet steel piling in 1975.
1971: A beach nourishment (sand replenishment) project moved 200,000 cubic yards
of sand from Cape Hatteras Point to the beach in the lighthouse area.
1973: Another beach nourishment project moved an additional 1,300,000 cubic yards
of sand from Cape Hatteras Point to the beach in the lighthouse area. At this time,
the ocean was approximately 175 feet from the old lighthouse ruins which were located
600 feet south of the lighthouse.
1978: High tides began chipping away at the stone foundation of the old lighthouse
ruins.
1980: A severe blizzard in March destroyed the remaining lighthouse ruins. The
same storm flanked the beach anchor point of the southern groin (the one nearest
the lighthouse). This flanking allowed storm driven or high tide waves to flow between
the steel and concrete jetty and the softer sand dunes, eroding more sand with each
wave. Emergency protective measures were initiated in October 1980 as the result
of a northeaster. Rubble was placed at the base of the eroding escarpment nearest
the lighthouse. The following month, the groin nearest the lighthouse was extended
landward about 150 feet. Unfortunately, the ocean washed completely around the extension
in December and forced a second emergency protection project as the tide came to
a point approximately 50 feet from the lighthouse. The December project pushed the
sea back to about 100 feet from the structure.
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1981: Beginning in May, William Garrett installed the first of some 250 units
of "Seascape." Designed by Garrett, these polypropylene devices consist
of hollow gravel-filled tubes with connecting fronds. Dropped offshore in about 10
feet of water, the fronds are designed to catch suspended sand particles, linking
them into an underwater sandbar, thereby helping build up the beach. In November,
a severe northeaster necessitated a third emergency protection project using additional
rubble. Although ocean overwash was common, no erosion was noted in the immediate
vicinity of the lighthouse. The groin nearest the lighthouse was extended landward
another 150 feet in December.
Senator Helms and Governor Hunt united to sponsor a statewide "Save Cape
Hatteras Lighthouse Committee."
1982: In April 1982, a public workshop outlined goals and alternatives for interim
and long range protection for the lighthouse. In July, an Environmental Assessment
was circulated listing protection alternatives developed by the Corps of Engineers.
The preferred alternative for long term protection is a seawall (revetment) encircling
the lighthouse. Other alternatives under consideration include moving the lighthouse,
offshore breakwaters, and additional groins. For interim protection, in September,
approximately 700 sandbags were placed in a protective dike around the lighthouse.
The bags, made of a woven polypropylene, were partially donated by Phillips Fibers,
a subsidiary of Phillips Petroleum. In October, an additional 5,000 units of "Seascape"
were installed by the Save Cape Hatteras Lighthouse Committee. The groin nearest
the lighthouse was extended landward about 150 feet (it was last extended in 1980).
Although the beach accreted in the late fall, a series of storms in the winter and
into early 1983 proved the continuing vulnerability of the lighthouse.
1983: The Corps of Engineers developed specifications for a scour protection mat,
or riprap sleeve, for the south groin to ensure its integrity and prevent its flanking
by overwash. The Corps began planning and testing for the revetment.
1984: The scour protection mat for the south groin was installed in January and
February. The planning for the revetment continued with wave tank modeling at the
Corps of Engineers, Vicksburg, Mississippi, Experiment Station.
1985: Specifications for the seawall/revetment, to encircle the lighthouse, were
refined based upon wave tank modeling results.
1986: Specifications for the seawall/revetment were completed. The Save Cape Hatteras
Lighthouse Committee placed 2,700 additional units of artificial seaweed in August
1986.
1987: Funding secured for seawall/revetment alternative. A private organization,
"Move The Lighthouse Committee," presented documentation of relocation
technologies not available in earlier protection planning. The National Park Service
contracted with the National Academy of Sciences (NAS) for an independent review
of all relevant information as to the best long term protection, considering risks,
environmental impacts, visitor impacts and costs.
1988: In April, NAS presented its final report, Saving Cape Hatteras Lighthouse
from the Sea, recommending that the Lighthouse be relocated. A committee formed by
the National Park Service established the proposed on-ground location should the
lighthouse be relocated. The National Park Service also began work on an Environmental
Assessment of Alternatives.
1989: In early 1989, a topographical map of the relocation area was developed,
including soil testing, to assist in final site planning. The Environmental Assessment
was distributed for public review in June 1989. The Southeast Regional Director announced
in December that the NAS recommended alternative of relocating the lighthouse had
been selected by the National Park Service as its preferred alternative.
1990: NPS funding of $59,000 and a $16,000 donation from the Save Cape Hatteras
Lighthouse Committee were applied to refurbishment of the sandbag revetment. The
project was completed during the summer. A contract was awarded to International
Chimney Corporation for $946,380 to perform structural integrity restoration of the
lighthouse. Completion of this project improved the lighthouse’s ability to withstand
the rigors of relocation. Other interim protection measures, such as repair of the
groin field, were under study.
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1991: The NPS Southeast Regional Office was in the final stages of completing
the environmental requirements for moving the lighthouse. The NPS Denver Service
Center established a team to prepare a Request for Proposals relative to a move.
1992: Work performed under the 1990 rehabilitation contract with International
Chimney Corporation (ICC) was completed. The Save Cape Hatteras Lighthouse Committee
donated $10,000 to fund repairs to the lighthouse roof; ICC performed this work.
NPS contracted to restore the sandbag revetment damaged by the Halloween Storm of
1991; Denver Service Center (DSC) awarded a contract to Howard, Needles, Tammen,
and Bergendoff of Alexandria, Virginia, for site development relative to lighthouse
relocation. Contract negotiations by DSC were underway with a prospective contractor
for development of relocation specifications. In November, a committee appointed
by the Regional Chief Scientist assessed beach erosion and risk level at the lighthouse
and provided recommendations for interim protection.
1993: Southeast Regional Director requested that the Denver Service Center place
the contract for relocation specifications on hold so that the funds could be used
for emergency interim protection measures. In September, Hurricane Emily damaged
the lighthouse lantern deck handrail and windows.
1994: The southern most groin, damaged over the years by constant battering from
the ocean, was repaired in an effort to improve in-place interim protection. Hurricane
Gordon passed within 100 miles of the area resulting in extensive erosion and dune
breaching to the south and north of the lighthouse. There was also significant damage
to the sandbag revetment, the repair of which resulted in the placement of 380 3000#
sandbags to rebuild and strengthen the protection.
1995: The National Park Service supported two studies to aid in interim protection
management for the lighthouse. The U.S. Army Corps of Engineers prepared specifications
and impact analysis associated with installation of a new forth groin to be added
south of the existing groin field. Their study included an estimate of the erosion
control effectiveness of the structure and the expected longevity of the installation.
A committee of noted coastal engineers and geologists headed by Dr. Robert Dolan
of the University of Virginia prepared a report which synthesized the current knowledge
of coastal erosion, inshore ocean climate including bottom conditions, and storm
history in the vicinity of the lighthouse. This data will be used to produce a multi-risk
analysis for the lighthouse which will aid the Park Service in making interim protection
measure decisions. The landward end of the south groin was rehabilitated with 184
feet of steel sheetpiling.
1996: U.S. Army Corps of Engineers issues their Design Report and Environmental
Assessment for the fourth groin alternative. Approximately 300 sandbags (3000#@)
are placed to both the north and south sides of the lighthouse as part of the continuing
interim protection program.
North Carolina State Senate Pro Tempore Marc Basnight commissions a team of North
Carolina State University engineers and coastal geologists/ecologists to revisit
and assess the NAS 1988 report Saving Cape Hatteras Lighthouse from the Sea.
1997: The report by the Ad Hoc Committee of Faculty at North Carolina State University
reviewing and updating the 1988 NAS report is delivered to North Carolina Senate
Pro Tempore Marc Basnight; the report endorses the NAS report and recommends that
if the Cape Hatteras Lighthouse is to be preserved for enjoyment by future generations,
it must be moved, and moved now. An effort to include within the FY1998 Federal Budget
the $12M needed to move the lighthouse falls short; however, $2M was appropriated
to begin the planning, design and request for quotes. The design program underwent
a Value Analysis by the Park Service in December which resulted in a revised program/plan.
Future Prognosis: The revised design plan will be reviewed by WASO level staff,
Request for Quotes reviewed and shortlisted in February, 1998 by select panel; shortlisted
proposals resubmitted in detail, reviewed by select panel in April, and contract
awarded in June 1998.
The additional $10M is anticipated to be in the President’s budget request to
Congress for FY1999. Actual project construction will begin once Congress appropriates
the funds. The project is anticipating a May 1999 move event.
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