North Carolina Water Science Center
The U.S. Geological Survey (USGS) operates more than 200 streamgages across the State of North Carolina to monitor river stage and streamflow. During flooding from Hurricanes Frances and Ivan in September 2004, period-of-record peak river stages were recorded at more than 20 sites in western North Carolina.
Many of the USGS streamgages in the Catawba, French Broad, and Pigeon River basins recorded period-of-record high stages after the passage of Frances. Several of these peaks were then exceeded following Hurricane Ivan at locations in the Pigeon River basin in North Carolina. Some of these streamgages were active during the floods of 1916 and 1940, yet flooding in September 2004 eclipsed many of the earlier events, which were considered the benchmarks for all floods measured since then in the mountains of North Carolina.
USGS streamgaging stations continually monitor river stage, but USGS staff must visit the sites during flood events and directly measure the streamflow with specialized measuring equipment. Sometimes peak streamflow cannot be measured directly because of the nature of the storm. Flashy peaks, which are more typical in mountain streams, can rise and fall before staff can safely travel to the site. In addition, extremely high stream velocities or large volumes of debris in the flow can create unsafe measuring conditions at the site. When these situations occur, peak streamflow is indirectly measured from high-water mark data collected after the event and subsequent surveys of stream channels and estimation of hydraulic conditions during the event. Since the passage of Hurricanes Frances and Ivan, USGS staff have been working on the computations of these indirect measurements of streamflow. Preliminary results of these analyses for selected sites in western North Carolina are listed below (table 1). The peak river stages recorded by the gage and peak streamflows determined from analysis of direct or indirect measurements are provided.
Peak river stage information is helpful in putting storms in historical context and determining the extent of flooding across the landscape, but peak streamflow (the volume of water passing a given location at the peak of an event) is critical in determining the recurrence interval or relative frequency of such an event. This information also is provided in table 1. Flood-frequency statistics, which report the streamflow values associated with the 100-year flood and the 2-, 5-, 10-, 25-, 50-, 200-, and 500-year events, generally are updated for USGS streamgaging stations about every 10 years. The most recent compilation of these statistics is available online at http://nc.water.usgs.gov/floodstats/ and includes information on the annual peaks for the period of record at each streamgage through 1996. (More information on flood-frequency analysis and flood forecasting is available online at http://water.usgs.gov/pubs/fs/FS-229-96/ and http://water.usgs.gov/wid/FS_209-95/mason-weiger.html )
Station number | Station name | Period of record (begin year) |
Peak river stage prior to September 2004 (year occurred) |
HURRICANE FRANCES September 7-9, 2004 |
HURRICANE IVAN September 17-18, 2004 |
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Peak river stage for event (feet) |
Peak streamflow (ft3/s) |
Approximate recurrence interval (years) |
Peak river stage for event (feet) |
Peak streamflow (ft3/s) |
Approximate recurrence interval (years) |
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These data are provisional and subject to revision pending publication in Water Resources Data - North Carolina Water Year 2004 All peak stages for Hurricane Frances on September 8th unless otherwise noted. All peak stages for Hurricane Ivan on September 17th unless otherwise noted. N/D = Recurrence interval not determined because period of record is less than 10 years. Peak river stage cells shaded in red indicate new period of record peak stages. |
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02137727 | Catawba River near Pleasant Gardens | 1981 -� | 15.22 (1994) |
17.55 | 23,000 | 200-500 | 13.64 | 11,700 | 10 |
02138500 | Linville River near Nebo | 1922 -� | 11.40 (1940) |
13.7 | 42,600 | 200-500 | 11.26 | 23,500 | 50 |
0213903612 | Catawba River near Calvin | 1991 -� | 16.40 (1994) |
26.3 | 52,600 | 200-500 | 14.86 (Sept 18) | 14,300 | 50 |
02140991 | John's River near Arney's Store | 1985 -� | 25.23 (1994) |
28.6 | 39,000 | 50 | 16.53 | 10,600 | 2-5 |
02143000 | Henry Fork near Henry River | 1941- | 18.71 (1990) |
18.04 | 11,500 | 10 | 2.12 (Sept 18) |
260 | <2 |
02143040 | Jacob Fork at Ramsey | 1961 -� | 19.74 (1975) |
18.93 | 6,550 | 50 | 2.54 | 113 | <2 |
02149000 | Cove Creek near Lake Lure | 1950 -� | 18.53 (1957) |
18.41 | 6,550 | 10 - 25 | 10.75 | 2,930 | <2 |
02150495 | Second Broad River near Logan | 1998 -� | 14.89 (2003) |
15.91 | 4,450 | N/D | 9.48 | 1,690 | N/D |
02151500 | Broad River near Boiling Springs | 1925 -� | 24.30 (1928) |
17.48 (Sept 9) | 36,900 | 10 - 25 | 8.62 (Sept 18) |
12,600 | <2 |
02152100 | First Broad River near Casar | 1959 -� | 16.70 (1975) |
19.89 | 12,500 | 10 | 2.37 | 296 | <2 |
03161000 | South Fork New River near Jefferson | 1924 | 22.50 (1940) |
11.73 | 14,700 | 10-25 | 8.58 | 7,550 | 2-5 |
03439000 | French Broad River at Rosman | 1935 -� | 14.95 (1964) |
12.60 | 8,660 | 10-25 | 12.76 | 8,910 | 10-25 |
03440000 | Cathey's Creek near Brevard | 1944-1958������������������ 1986 - 2004 | 7.28 (1994) |
6.12 | 1,770 | 10 | 5.29 | 1,260 | 5 |
03441000 | Davidson River near Brevard | 1920 - 1990,� 1993 -� | 12.08 (1994) |
11.86 | 7,450 | 25-50 | 10.16 | 6,090 | 10-25 |
03443000 | French Broad River at Blantyre | 1920 -� | 25.50 (1964) |
25.81 (Sept 9) |
20,600 | 25-50 | 22.06 (Sept 18) |
11,900 | 5-10 |
03446000 | Mills River near Mills River | 1924 - 1926, 1933 - | 13.62 (1940) |
12.31 | 7,270 | 25-50 | 11.84 | 6,090 | 10-25 |
03447687 | French Broad River near Fletcher | 2001 -� | 12.5 (2003) |
20.07 | 25,300 | N/D | 17.60 | 20,200 | N/D |
03447894 | Bent Creek near Glen Bald | 2001 -� | 4.23 (2003) |
5.29 | 626 | N/D | 9.81 | 3,000 | N/D |
0344894205 | North Fork Swannanoa River near Walkertown | 1989 -� | 8.19 (1995) |
10.3 | 7,000 | 50-100 | 8.27 | 3,510 | 10 |
03450000 | Beetree Creek near Swannanoa | 1926 - | 6.20 (1940) |
4.44 | 277 | 2-5 | 4.40 | 874 | 25-50 |
03451000 | Swannanoa River at Biltmore | 1920 - 26, 1934 -� | 19.00 (1940) |
19.22 | 12,900 | 50-100 | 16.74 | 10,300 | 25-50 |
03451500 | French Broad River at Asheville | 1895 -� | 23.10 (1916) |
14.55 | 47,300 | 100� | 11.57 | 30,100 | 10-25 |
03451690 | Newfound Creek near Alexander | 2000 -� | 8.13 (2003) |
7.82 | 1,300 | N/D | 20.60 | 17,000 | N/D |
03453000 | Ivy River near Marshall | 1933 -73,� 1994 -� | 17.21 (1995) |
9.56 | 3,070 | <2 | 14.21 | 5,450 | 2 -5 |
03453500 | French Broad River at Marshall | 1942 -� | 13.64 (1977) |
11.33 | 39,100 | 10-25 | 12.72 | 48,000 | 25 |
03455500 | West Fork Pigeon River above Lake Logan near Hazelwood | 1954 -� | 9.50 (1966) |
9.23 | 7,600 | 10 - 25 | 10.83 | 12,700 | 200 - 500 |
0345577330 | West Fork Pigeon River near Retreat | 1988 -� | 8.97 (1994) |
12.13 | 10,400 | 50 | 14.15 | 15,600 | 500 |
03456100 | West Fork Pigeon River at Bethel | 1981 -� | 12.63 (1994) |
14.9 | 12,900 | �>50 | 16.27 | 19,000 | 500 |
03456500 | East Fork Pigeon River near Canton | 1954 -� | 11.19 (1973) |
12.03 | 11,700 | 25-50 | 13.09 | 13,000 | 50 |
03456991 | Pigeon River near Canton | 1907 - 09,� 1928 -� | 20.75 (1940) (different gage datum) |
20.7 | 41,000 | >500 | 22.80 | 48,000 | >500 |
03459500 | Pigeon River at Hepco | 1927 -� | 15.82 (1940) |
16.77 | 34,300 | 50 - 100 | 17.68 | 38,000 | 100 - 200 |
03460000 | Cataloochee Creek near Cataloochee | 1933-1952,� 1962 - | 8.08 (1963) |
6.36 | 2,680 | 2-5 | 6.29 | 2,600 | 2-5 |
03460795 | Pigeon River below Power Plant near Waterville | 1997 -� | 16.39 (2003) |
17.22 | 30,500 | N/D | 18.88 | 39,000 | N/D |
03463300 | South Toe River near Celo | 1957 -� | 17.41 (1977) |
15.5 | 28,000 | 200 | 13 | 22,000 | 50 -100 |
03479000 | Watauga River near Sugar Grove | 1939 -� | 29.60 (1940) |
19.07 | 17,000 | 10-25 | 21.90 | 23,000 | 50 |
03500000 | Little Tennessee River near Prentiss | 1943 -� | 17.30 (1964) |
8.05 | 3,290 | <2 | 15.92 | 11,200 | 50-100 |
03500240 | Cartoogechaye Creek near Franklin | 1961 -� | 12.96 (1964) |
10.76 | 2,420 | 2-5 | 14.12 | 6,600 | 100 |
0350056050 | Cullasaja River near Highlands | 2001 -� | 10.18 (2002) |
12.07 (Sept 7) |
2,780 | N/D | 16.15 | 5,300 | N/D |
03503000 | Little Tennessee River at Needmore | 1943 -� | 12.87 (1964) |
8.31 | 11,200 | 2-5 | 12.33 | 20,900 | 25 |
03504000 | Nantahala River near Rainbow Springs | 1940 -� | 9.70 (1949) |
5.93 (Sept 7) |
2,940 | 2-5 | 8.29 | 4,950 | 10-25 |
03508050 | Tuckasegee River nr Cullowhee | 2004 | New Gage | 17.37 | N/A | N/D | 16.37 | N/D | N/D |
03510577 | Tuckasegee River at Barker's Creek | 2004 | New Gage | 12.52 | N/A | N/D | 13.26 | N/D | N/D |
03512000 | Oconaluftee River near Birdtown | 1945- | 12.46 (1969) |
4.50 (Sept 9) |
3,200 | <2 | 7.79 | 8,000 | 2 |
03513000 | Tuckasegee River at Bryson City | 1897- | 15.96 (1940) |
9.96 | 18,000 | 2-5 | 13.58 | 30,700 | 5-10 |
0351706800 | Cheoah River near Bearpen Gap near Tapoco | 1999- | 13.3 (2003) |
2.75 | 134 | N/D | 7.40 | 3,500 | N/D |
0351751500 | Cheoah River near Tapoco | 1999 -� | 12.09 (2003) |
2.50 | River Stage only site | N/D | 8.08 | River Stage only site | N/D |
03548330 | Brasstown Creek at Brasstown | 2000- | 14.94 (2003) |
8.96 | 1,580 | N/D | 14.17 | 4,140 | N/D |
03548500 | Hiwassee River above Murphy | 1897- 2004 | 13.88 (1973) |
6.50 | 4,090 | <2 | 9.29 | 8,490 | <2 |
03550000 | Valley River at Tomotla | 1904- | 20.5 (1906) |
2.68 | 290 | <2 | 6.82 | 2,090 | <2 |