Geology topics

William P. Carey

Publications and source records attributed to William P. Carey.

5 recordsLinked to original sources

USGS2010

Interaction of fine sediment with alluvial streambeds

More knowledge is needed about the physical processes that control the transport of fine sediment moving over an alluvial bed. The knowledge is needed to design rational sampling and monitoring programs that assess the transport and fate of toxic substances in surface waters because the toxics are often associated with silt- and clay-sized particles. This technical note reviews some of the past research in areas that may contribute to an increased understanding of the processes involved. An alluvial streambed can have a large capacity to store fine sediments that are extracted from the flow when instream concentrations are high and it can gradually release fine sediment to the flow when the instream concentrations are low. Several types of storage mechanisms are available depending on the relative size distribution of the suspended load and bed material, as well as the flow hydraulics. Alluvial flow tends to segregate the deposited material according to size and density. Some of the storage locations are temporary, but some can store the fine sediment for very long periods of time.

Water Resources Research↗

USGS2007

Variability in measured bedload-transport rates

Variability in bedload-transport rates during constant water discharge is an inherent part of the bedload-transport process. Although this variability has been measured extensively in the laboratory, similar information generally is not available from field measurements. During a four-day period of nearly constant water discharge, four sets of consecutively collected bedload samples, ranging from 43 to 120 samples, were obtained at the same cross channel location using a standard 65-pound Helley-Smith bedload sampler. When the measured transport rates are converted to dimensionless rates and plotted as cumulative frequency distributions, they show good agreement with a theoretical probability distribution function of rates derived for the case of ripples on dunes. The distributions show that during constant water discharge individual measured rates at a fixed point vary from near zero to four times the mean rate, and 60 percent of the sampled rates will be less than the mean. Because of the large variation in transport rates that occurs at every location in the cross section, many observations are required to establish an accurate estimate of the mean rate at any given location.

Tennessee↗

USGS1988

History of suspended-sediment data collection and inventory of available data for the Tennessee and Cumberland River basins

Since the early 1930’s, a considerable amount of suspended-sediment data has been collected in the Tennessee and Cumberland River basins, primarily by the Tennessee Valley Authority and the U.S. Geological Survey. These data sets cover a wide range of drainage areas and sampling frequencies. The most valuable data sets are those where the frequency of sampling was sufficient to compute daily sediment records. In 1934 and 1935, the Tennessee Valley Authority established 5 1 daily record suspended-sediment stations on the Tennessee River and its major tributaries. Most of these stations were operated for 3 to 4 years, but nine of the stations were operated for 8 years. From 1962 to 1965, the Tennessee Valley Authority again collected daily sediment record at 10 of the original 5 1 stations. In addition to the data sets collected on the major rivers, the Tennessee Valley Authority has conducted several intensive studies of small watersheds throughout the Tennessee River Basin. In the Cumberland River basin, daily sediment records have been collected primarily by the Survey. Daily stations have been operate for various periods on 17 basins ranging in size from 0.67 to 1,977 square miles, with the earliest date of daily record being October 1953. All of these daily stations are located in the upper Cumberland River basin upstream of any major impoundments. Periodic sediment data have been collected by the U.S. Geological Survey at 194 stations in the Tennessee River basin and at 106 stations in the Cumberland River basin, however, the number of samples per station is quite low. Eighty-six percent of the periodic stations in the Tennessee River basin and 91 percent of the periodic stations in the Cumberland River basin have 30 samples or less.

Tennessee↗

USGS1984

Sediment characteristics of Tennessee streams and reservoirs

Suspended sediment and reservoir sedimentation data have been analyzed to determine sediment yields and transport characteristics of Tennessee streams Data from 31 reservoirs plus suspended sediment data from TVA sampling efforts in the 1930’s and 1960’s, and U.S. Geological Survey efforts from 1975-82 have been used. Results of the analyses show that the measured suspended-sediment is mostly silt and clay-size material even in the sand bed channels of western Tennessee. Samples of suspended sediment rarely exceed 25 percent sand. Computed unmeasured load is less than 10 percent of the total sediment load in western Tennessee. Unmeasured load has not been computed for middle and eastern Tennessee streams because the bed material is generally coarse and quite variable. However, unmeasured load in these streams is believed to be less than 5 percent of total load. Transport curves show that when flow is less than about 1 cubic foot per second per square mile, western Tennessee streams have higher concentrations than middle or eastern streams. When flow exceeds about 10 cubic feet per second per square mile, however, concentrations in middle and eastern streams can equal or exceed those in western streams. The more efficient sediment-delivery processes operating in middle and eastern Tennessee basins are responsible for the rapid increases in suspended sediment concentrations with increasing flow. Sediment yields for middle and eastern Tennessee basins generally are less than 800 tons per square mile per year, however, heavily strip-mined basins can have yields from 1,000 to 3,000 tons per square mile per year. Yields for the heavily agricultural and channelized basins of western Tennessee generally range from 700 to 1,000 tons per square mile per year.

Tennessee↗

USGS1984

EFFECTS OF RESOURCE DEVELOPMENT ON WATER QUALITY IN THE BIG SOUTH FORK NATIONAL RIVER AND RECREATION AREA, TENNESSEE AND KENTUCKY.

The South Fork Cumberland River begins in Tennessee at the confluence of the New River and Clear Fork. Strip mining for coal in the New River basin has been ongoing for decades with little reclamation prior to 1977. Water-quality data show that suspended-sediment and dissolved-constituent loads from the New River dominate the water quality in the National River and Recreation Area. The suspended sediment can impart a highly turbid and aesthetically displeasing appearance to the water during low-flow periods which are times of maximum recreational use. High suspended-sediment concentrations are also potentially harmful to the aquatic habitat in the Recreation Area. In addition to the suspended-sediment load, a large supply of coarse material is slowly moving through the channels of the New River basin toward the Recreation Area.

Conference Paper↗