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D.E. Ladd

Publications and source records attributed to D.E. Ladd.

4 recordsLinked to original sources

Alluvial Bars of the Obed Wild and Scenic River, Tennessee

In 2004, the U.S. Geological Survey (USGS) and the National Park Service (NPS) initiated a reconnaissance study of alluvial bars along the Obed Wild and Scenic River (Obed WSR), in Cumberland and Morgan Counties, Tennessee. The study was partly driven by concern that trapping of sand by upstream impoundments might threaten rare, threatened, or endangered plant habitat by reducing the supply of sediment to the alluvial bars. The objectives of the study were to: (1) develop a preliminary understanding of the distribution, morphology, composition, stability, and vegetation structure of alluvial bars along the Obed WSR, and (2) determine whether evidence of human alteration of sediment dynamics in the Obed WSR warrants further, more detailed examination. This report presents the results of the reconnaissance study of alluvial bars along the Obed River, Clear Creek, and Daddys Creek in the Obed WSR. The report is based on: (1) field-reconnaissance visits by boat to 56 alluvial bars along selected reaches of the Obed River and Clear Creek; (2) analysis of aerial photographs, topographic and geologic maps, and other geographic data to assess the distribution of alluvial bars in the Obed WSR; (3) surveys of topography, surface particle size, vegetation structure, and ground cover on three selected alluvial bars; and (4) analysis of hydrologic records.

Scientific Investigations Map↗

Construction, lithologic, and water-level data for wells near the Dickson County landfill, Dickson County, Tennessee, 1995

Organic compounds were detected in water samples collected from Sullivan Spring during several sampling events in 1994. Prior to this, the spring was the drinking-water source for two families in the Dickson, Tennessee area. An investigation was conducted by the U.S. Geological Survey, in cooperation with Dickson County Solid Waste Management, to determine if Sullivan Spring is hydraulically downgradient from the Dickson County landfill. This report describes the data collected during the investigation. Five monitoring wells were installed near the northwestern corner of the landfill at points between the landfill and Sullivan Spring. Water-level measurements were made on June 1 and 2, 1995, at these wells and 13 other wells near the landfill to determine ground- water altitudes in the area. Water-level altitudes in the five new monitoring wells and three other landfill-monitoring wells were higher (750.04 to 800.17 feet) than the altitude of Sullivan Spring (approximately 725 feet). In general, wells in topographically high areas had higher water-level altitudes than Sullivan Spring and wells near streams in lowland areas.

Tennessee↗

Base-flow data for the Little West Fork Basin, Fort Campbell, Tennessee and Kentucky, 1993 and 1994

Base-flow data were collected from selected sites within the Little West Fork basin during high and low base-flow conditions to support a study of the source and movement of ground water that supplies the Fort Campbell Military Reservation. Stream and spring discharge, water temperature, and specific-conductance data were collected during low base-flow conditions from 64 sites on September 1 and 13,1993, and again on October 18 and 19, 1994. High base-flow data were collected from 63 sites on March 17 and 18, 1994. Discharge was greater during high base-flow conditions than during low base-flow conditions. Major tributaries on the south side of the study area consistently had lower flow than the tributaries on the north side. Discharge data were used to categorize stream reaches and sub-basins. Stream reaches were categorized as gaining or losing, wet, dry, unobserved for each base-flow measurement period. More gaining stream reaches occurred during the high base-flow period than either of the low base-flow periods. More dry stream reaches occurred during the two low base-flow periods than during the high base-flow period. Sub-basin areas with surplus or deficient flow were also defined. Many areas of deficient flow occurred near the headwaters of the Little West Fork basin under all base-flow conditions. Fewer areas of deficient flow occurred near the mouth of the basin. The flow per square mile for each major tributary basin in the study area was also calculated. The values of flow per square mile for the Noah Spring Branch and Dry Fork Creek basins in the northern part of the study area were greater than those for the Piney Fork and Fletchers Fork basins in the southern part of the study area under all base-flow conditions.

Kentucky, Tennessee↗