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T. C. Stamey

Publications and source records attributed to T. C. Stamey.

9 recordsLinked to original sources
USGS2000

Trace elements and semi-volatile organic compounds in bed sediments from streams and impoundments at Fort Gordon, Georgia

In May 1998, the U.S. Geological Survey, in cooperation with the Environmental and Natural Resources Management Office of the U.S. Army Signal Center and Fort Gordon, investigated the presence and disbursal of trace elements and semi-volatile organic compounds in bed sediments from selected streams and impoundments at the Fort Gordon military installation near Augusta, Georgia. Concentrations of 18 trace elements and total organic carbon, and 66 semi-volatile compounds were determined from analysis of the fine-grained fraction of bed-sediment samples from 29 surface-water deposition locations. Analysis of the bed-sediment data indicates that commercial and industrial land-use areas generally are associated with the highest concentrations of trace elements and semi-volatile organic compounds, and the greatest occurrence and distribution of trace elements and semi-volatile organic compounds in bed sediments at Fort Gordon. Bed sediment collected at sites having drainage areas less than 1.0 square mile and greater than 45 percent commercial and industrial land uses, have the most occurrences and the highest concentrations of trace elements and semi-volatile organic compounds. Sampling sites having less than 2 percent commercial and industrial land uses had the lowest concentrations, regardless of drainage basin size. Relative rankings and evaluation of individual trace element and semi-volatile organic compound concentration data identified two sites that have substantially higher sediment-quality scores than the other sites. This suggests that these sites have the greatest potential risk for adverse effects on aquatic life. The effects of these elevated trace element and semi-volatile organic compound concentrations on aquatic life in these basins may merit further investigation.

Georgia↗
USGS1989

Effects of channel relocation and proposed bridge construction on floodflows of the Catawba River near Marion, North Carolina

The relocation of a part (about one-half a mile) of the Catawba River near Marion, North Carolina, and the proposed addition of a main bridge and an overflow bridge of U.S. Highway 221 have created the need for a current evaluation of the effects of these physical changes on floodflow in the river. The 100-year flood discharge, elevation-discharge relations, flood profiles, floodway, and flooding effects were determined for 1988 and for proposed bridge conditions. Analysis of data indicates that for the 100-year flood, the maximum amount of backwater effect from the proposed bridges would be 1.2 feet, and backwater would extend upstream about 6,800 feet. The 100-year flood elevation in the relocated channel reach will be about 6 feet lower than elevations determined in a 1983 U.S. Soil Conservation Service flood study.

North Carolina↗
USGS1989

Sediment transport and accretion and the hydrologic environment of Grove Creek near Kenansville, North Carolina

The Grove Creek basin includes an area of about 42 square miles in Duplin County, southeastern North Carolina. This report evaluates sediment transport and sediment-accretion rates in the lowermost 9-mile reach of Grove Creek by using hydrologic, dendrologic, and radioisotopic data collected at seven sites along the study reach. Hydrologic data indicate two discharge frequencies. In the swampiest reaches downstream of site 5, inundation occurs 35 percent of the time; above this site, inundation occurs about 15 percent of the time. For the period from October 1982 through September 1987, overbank flows at site 4 occurred 82 times and lasted a total of 632 days with a maximum duration of 3 months. Distribution of tree species indicates that water-tolerant bald cypress have developed along the lowermost 7 miles of Grove Creek where the flood plain is inundated 35 percent of the time. These swampy conditions have been in existence across limited parts of the flood plain for the last 80 to 150 years. In contrast, the upstream sites have been comparatively dry for the same period. The sediment that is transported in Grove Creek is predominately silt and clay. Measured suspended-sediment concentrations at discharges less than 100 cubic foot per second are less than 15 milligrams per liter; concentrations at higher discharges did not exceed 67 milligrams per liter. Calculated suspended-sediment loads ranged from 75 to 444 tons per year at the various data-collection sites on Grove Creek. Sediment-accretion rates estimated from dendrologic data ranged from 0.03 foot per year to 0.06 foot per year. The highest accretion rates occur in the downstream swampy reaches and are due to channel braiding, low channel gradients and flow velocities, and high frequency and duration percentages of overbank flow, which result in the deposition of clay and silt over wide areas of the flood plain. Sediment-accretion rates along Grove Creek were also estimated by radioisotope methods. Sediment cores from the flood plain showed detectable levels of cesium-137, lead-210, and radium-226. Cesium-137 was not present in the sediment cores below a depth of 10 inches; this indicates a maximum accretion rate of about 0.024 foot per year for the period 1952-87. Lead-210 and radium-226 data from these same sediment cores indicate an average accretion rate of 0.026 foot per year to a depth of about 2 feet. The maximum age of the flood-plain sediment at the 2-foot level is about 80 years. The atmosphere was confirmed as the source of excess lead-210 in flood-plain sediments by nearly matching calculated values of the lead-210 flux at each site with the measured value for atmospheric deposition.

North Carolina↗
USGS1987

Magnitude and frequency of floods in rural and urban basins of North Carolina

The applicability of the nationwide urban flood relations in the Piedmont and Coastal Plain provinces is evaluated. Data for 254 gaging stations on rural streams with 10 or more years of record were used in multiple linear regression analyses with basin and climatic variables, to derive regional relations for estimating flood discharges having recurrence intervals of 2- to 100-years. Rural relations are presented for three hydrologic areas: (1) Blue Ridge-Piedmont, (2) Coastal Plain, and (3) Sand Hills. Drainage area is the only basin characteristic in the relations. The average standard error of estimate of the relations for the Blue Ridge-Piedmont, Coastal Plain, and Sand Hills hydrologic areas is 44, 39, and 24%, respectively. Flood discharges for the 2-, 5-, 10-, 25-, 50-, and 100-year recurrence intervals for the 254 streamflow stations used in the regionalization study are also presented. Flood frequency distributions of simulated annual maximum discharges for four urban basins in the Coastal Plain indicate that the nationwide relations are applicable in the province. The root mean squared error for the 10- and 100-year flood discharges, using the nationwide relations, is 44% and 49%, respectively. Simulated data for six sites in the Piedmont were used to analyze the applicability of the nationwide urban relations in the province. The root mean squared error is 64% for the 10-year flood and 42% for the 100-year flood. No recommendation is made concerning use of the nationwide relations in the Piedmont.

North Carolina↗
USGS1985

Frequency and duration of flooding of Grove Creek near Kenansville, North Carolina, for present and proposed restored channel conditions

The Grove Creek basin includes an area of about 42 square miles in Duplin County, southeastern North Carolina. The North Carolina Department of Human Resources (DHR) proposes to implement a channel restoration project on about an eight-mile reach of Grove Creek. The purpose of the restoration program is to improve drainage, thereby reducing frequency and duration of overbank flooding and reducing the opportunity for mosquito breeding in frequently flooded areas adjacent to Grove Creek. This study evaluates the effects of the restoration on the frequency and duration of flooding within the study reach for present (1984) and proposed restored channel conditions. The proposed restored channel is estimated to increase the carrying capacity of the main channel from 10 to 19 times. The greatest reduction in areas of flooded land immediately adjacent to the study reach would be west of North Carolina Highway 11 (between sites 4 and 6) and would be reduced by an average of 29 percent during floods up through the 10-year flood level and reduced by an average of 5 percent for the 25- to 100-year flood levels. An average reduction of 1 percent is indicated for areas inundated east of North Carolina Highway 11 (for sites 1 through 3) for the 2-, 5-, 10-, 25-, 50-, and 100-year floods; while reductions in inundated area of the total study reach of 13, 5, 4, and 1.5 percent are indicated for the 2-, 5-, 10-, and 100-year floods, respectively. Overbank flooding during 1983 and 1984 water years occurred 32 times and persisted from a few hours up to about 3 months. For proposed restored-channel conditions, overbank flooding would have been reduced to 5 occurrences, and areal flooding would have persisted from a few hours to about 2 days. Flooding on the Northeast Cape Fear River causes variable backwater conditions on the lower Grove Creek study reach. A 100-year flood on the Northeast Cape Fear River would create backwater for about 1.5 miles upstream on Grove Creek.

North Carolina↗