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following the stonn, and were located landward of the original dune line. The replacement dunes were approximately 5 feet lower than the dunes destroyed during the stonn, Another heavily eroded area at Rodanthe (fig. 23) led to the condem- nation (fig. 27) and loss of several ocean-front houses. The laser altime- try data clearly reveal the lost houses (fig, 28). This spatial variability of high erosional rates and lower ero- sional rates was repeated along the coast over scales of miles, and may be related to varying nearshore geol- ogy, Identification of the causes of the variability in erosional rates is a major research objective of the USGS Coastal and Marine Geology Program. Whereas Hurricane Dennis was notable because of duration, Hurri- cane Floyd at one time was one ofthe strongest stonns to threaten the east- ern coast of the United States this century. Hurricane Floyd made land- fall with sustained winds of 110 mph and a stonn surge of about 10 feet (Pasch and others, 2000). The maxi- mum surge occurred near high tide contributing substantially to exten- sive overwash, dune retreat, and damage to homes on barrier islands such as Oak and Topsail Islands (fig. 23), As was done following rrw- r-- Figure 27. Houses standing in the surf at Rodanthe, N.C. With no protective dunes remaining to protect the houses. the balcony supports were destroyed during the storm. These houses have been condemned. Hurricane Dennis on the northern Outer Banks, shoreline topography was measured using airborne laser altime- try immedi- ately following Hurricane Floyd. Initial results indicate that the effects of Hurricane Floyd on shoreline erosion and dune retreat were greater than the effects of Hurricane Bonnie, a Category 3 - ~<" -- "'~ -.- --::""'""~ ~ ., - Ocean ovenvash resulting from Hurricane Floyd '" " '" ~ Two :V1omhs of Flooding in Eastern North Carolina. September--October 1999 stonn that made landfall in the same area in 1998. ~ w o u z Houses near the surf with little or no protective dunes, Oak Island, N.C.