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August 1996 rainfall amounts were above average throughout much of central North Carolina. August rainfall was 1.34 inches above average at Greensboro; 3.08 inches above average at Burlington, and 2.10 inches above average at Fayetteville. Moreover,July rainfall was above average at many reporting stations in the eastern part of the State. Immediately prior to the hurricane on September 1-4, most stations east of Greensboro reported significant rainfall, including Greensboro (5-61 inches), Burlington (0.90 inch), Siler City (3-25 inches), Fayetteville (1.94 inches), New Bern (3-76 inches), and Wilmington (2.55 inches). Consequently, soils in these areas were at or near saturation and had limited capacity for storing the rainfall that fell during the passage of Hurricane Fran. Because of this excessive rainfall, flows at most gaging stations across north central and parts of eastern North Carolina were already well above average prior to the hurricane. Flows in the Neuse F loods resulting from Hurricane Fran, which passed through North Carolina on September 5-6,1996, were some of the most severe and widespread in the State in recent memory.The U.S. Geological Survey (USGS) is responsible for the collection and interpretation of water-resources information, including flood data, for the Nation. As such, the USGS, in cooperation with the North Carolina Department of Environment, Health, and Natural Resources, the U.S.Army Corps of Engineers, and numerous other State and local agencies, is continuing to document the effects of Hurricane Fran on the water resources of North Carolina.The purpose of this report is to present preliminary, selected information on the flooding and associated water-quality conditions which followed Hurricane Fran in North Carolina.

One of the great challenges faced by the Nation's water-resources scientists is the need for reliable information that will guide the protection of our water resources. That challenge is being addressed by Federal, State, interstate, and local water-resource agencies, and by academic institutions. Many of these agencies are collecting water-quality data for a host of purposes, including compliance with permits and water-supply standards; development of remediation plans for specific contamination problems; operational decisions on industrial, wastewater, or watersupply facilities; and research on water quality. Prominent is the need for information of regional and national scope, and on the trends and causes of water-quality conditions. Without this information, policy decisions may be based on information from a few localized problems. Conversely, a lack of information may lead to a false sense that some problems do not exist. In the past two decades, billions of dollars have been spent on water-quality data-collection programs. However, only a small part of the data collected for these programs has been obtained specifically to assess the status, trends, and causes of water-quality conditions on regional and national scales. Also, in some instances, the utility of these data for present and future regional and national assessments is limited by such factors as the areal extent of the sampling network, frequency of sample collection, and the types of water-quality characteristics determined. Water-quality data collected for permits and for compliance and enforcement purposes constitute a sizable source of information that may be suitable for regional and national assessments. Such data must, however, be carefully screened before use. The needs, uses, and types of water-quality data vary widely, and data collected for one purpose are not necessarily suitable for other purposes. In fact, the use of unsuitable data in regional or national assessments can be much worse than a lack of information, because the use of such data can lead to incorrect conclusions having far-reaching consequences. Accordingly, the U.S. Geological Survey, with cooperation from other agencies and from universities, has undertaken a three-phase study in Colorado and Ohio to determine the characteristics of existing Federal and other public-agency waterquality data-collection programs and to evaluate the suitability of the data bases from these programs for use in water-quality assessments of regional and national scope. This report describes results of the second phase of the study. This study does not imply that past and present data-collection programs have failed or are inappropriate for their intended purposes. The data from those programs may fully meet individual agency needs and fulfill their mandated requirements, yet may have only limited relevance to water-quality questions of regional and national scope. This study has depended heavily on cooperation and information from many Federal, State, regional, and local agencies and academ...

This report presents the results of analyses of trends in concentrations of nitrogen, phosphorus, suspended sediment, suspended solids, sodium, chloride, iron, zinc, manganese, and chlorophyll a at 34 stream and reservoir sites that are part of the Triangle Area Water Supply Monitoring Project. Trend results are discussed in relation to broad-scale changes in land cover that have occurred in the area since the mid-1970s.Data used for trend analysis of stream sites are from samples collected by the U.S. Geological Survey (USGS) from 1982 through 1987 for a study for the U.S. Army Corps of Engineers (Garrett, I990a and b), by the North Carolina Division of Water Quality (DWQ) from 1982 through 1995 for the statewide ambient water-Quality monitoring network. USGS science for e changing worldand by the USGS from 1988 through 1995 for the Triangle Area Water Supply Monitoring Project (Childress and Treece. 1996; Ragland and others, 1996). These three sources provide stream water-Quality data, collected monthly, which are ideally suited for trend analysis. Using continuous streamflow data from USGS gages, stream water-Quality data were statistically adjusted to eliminate the effects of changing streamflow.

Sedimentation in and flooding of the West Branch Shade River and its tributaries have been major concerns of residents and State and local officials. The area was extensively surface mined for coal between the mid-1940's and the early 1960's. Reclamation efforts immediately after mining were unsuccessful. The results have been elevated sediment loads and the subsequent loss of channel conveyance. Two sediment and stream-gaging stations were established on West Branch Shade River in the area of past mining to provide data to evaluate the effectiveness of current reclamation activities on reducing sediment loads. A third station was established on the East Branch Shade River in an unmined area as a control. From October 1983 through September 1984, the annual suspended-sediment yield per acre-foot of runoff was approximately two times as high for West Branch Shade River (0.51 ton per acrefoot of runoff) as for East Branch Shade River (0.28 ton per acrefoot). In addition, water quality of West Branch indicates that acidity is higher, pH is lower, and concentrations of dissolved sulfate and metals are higher than for East Branch. The concentration of coal in bed material increased in the downstream direction along West Branch Shade River. The concentration downstream in the West Branch was more than 20 times greater than in the East Branch.