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October was equivalent to about 83 percent of the total volume of the Sound, whereas under normal condi- tions, inflow volume during these 2 months is equivalent to about 13 percent of the volume of the Sound. This means that by the end of October, much of the water that was in the Sound at the begin- ning of September could have been displaced by floodwaters. Estimated mean water residence time was about 7 days for the Pamlico River and Neuse River estuaries during Sep- tember compared to a long- tenn annual average of 72 and 68 days, respectively, for these estuaries. Conse- quently, material that might nonnally be deposited or biochemically transfonned in the estuaries was trans- ported into Pamlico Sound. The cumulative load of nitrogen in Hurricane Floyd floodwaters dur- ing September IS-October 20 ranged from 450 tons in the Lumber River to 4,200 tons in the Neuse River near Fort Barnwell. The mean annual nitrogen in the Neuse River at Kinston is about 3,400 tons; about half of this load was carried by Hurricane Floyd floodwaters during this 36-day period. [n the Tar River at Tarboro, almost 80 percent of the mean annual nitrogen load of 2,200 tons was transported in Hurri- cane Floyd floodwaters. The total load of nitrogen carried in Hurricane Floyd floodwaters was quite similar to the total load carried by Hurricane Fran floodwaters in the Neuse, Tar, and Cape Fear Rivers, despite the generally greater total streamflow resulting from Hurricane Floyd. During the same period, phosphorus loads ranged from 30 tons in the Cape Fear River to 370 tons in the Neuse River near Fort Barnwell. The estimated phosphorus load in the Neuse River at Kinston was 66 per- cent of the mean annual phosphorus load of 350 tons, and the cstimated phosphorus load during flooding in the Tar River at Tarboro was 89 percent of the mean annual load of 270 tons. waves that pounded the coast. As a result, erosion of dunes between Cape Hatteras and Oregon [nlet was highly variable; in some areas, dunes retreated more than 100 feet, whereas in other areas the dunes were stable, The effects of Hurricane Floyd on shoreline erosion and dune retreat seem to have been greater than the effects of Hurricane Bonnie, a 1998 Category 3 stonn that madc landfall in the same area as Hurricane Floyd. Hurricanes and floods are complex natural events that occur with some regularity in North Carolina, as well as in many locations around the world. These natural events become natural disasters when people and property are located in positions vulnerable to the < ~ destructive effccts ofthesc ~ events. As the population increases in castern North Carolina, there is an incrcasing possibility that natural events will result in more costly and more deadly natural disasters (Barton and Nishenko, 1994), The lessons learned as a result of the hurricanes and floods of 1999 can be used to guide rebuilding and mitigation of the effects of future hurricanes and floods in North Carolina. Flooded home near Greenvil1e, N.C. Of the 47 different pesticide compounds analyzed, 17 were detected in floodwaters at concentra- tions ranging from 0.4 to 102 nano- grams per liter. The highest pesticide concentration detected was metola- chlor in the Neuse River at Smith- field. Metolachlor, prometon, atrazine, and carbaryl were the com- pounds most commonly detected, and metolachlor and car- baryl were detected in the greatest concentrations. The greatest number of pesticide compounds were detected in the Neuse River near Fort Barnwell. Although winds from Hurricane Dennis were not particularly strong, the stonn meandered about 150 miles off the coast of the northern Outer Banks for nearly a week, generating large " w o u z Grifton, N.C. Two Months of Flooding in Eastern Nonh Carolina, September-October ] 999