Geology topics

R.E. Thompson

Publications and source records attributed to R.E. Thompson.

4 recordsLinked to original sources

USGS1996

Statewide Floods in Pennsylvania, January 1996

Rivers and streams throughout Pennsylvania (fig. 1) experienced major flooding during January 1996. Flood stages (water-surface heights) and discharges (flows) in many of the Commonwealth's waterways were measured by the U.S. Geological Survey (USGS) and approached or exceeded record levels established during previous floods. Setting the stage for the flooding was an unusually cold beginning to the winter of 1995-96, which resulted in the early formation of ice in streams statewide. The anomaly of early ice was followed by a sequence of unusual meteorological events in January 1996, which, in many areas, resulted in the most widespread and severe flooding since that produced by tropical storm Agnes in June 1972. Locally, the flooding was the worst since August 1955 and, in some areas, since March 1936. In approximately 50 localities throughout Pennsylvania, flood effects were magnified when ice jams caused temporary damming of stream channels, resulting in the rapid rise of water levels and the subsequent overflow of water and ice onto flood plains. During the floods, the USGS collected stream-stage information on a near real- 42°-GffEAWa/CESJ DRWNAG. time basis at 189 streamflow-gaging stations across the Commonwealth. This information was used by various Federal, State, and local agencies to prepare flood forecasts and develop plans for emergency response.

Fact Sheet↗

USGS1995

An observed-streambed-scour index for selected bridges in southwestern Indiana, 1991

Streambed-scour was assessed at 1,338 federal-aid bridges in southwestern Indiana during 1991. The assessments were conducted as part of a 7-year study by the U.S. Geological Survey in cooperation with the Indiana Department of Transportation (INDOT) that will evaluate 5,600 bridge sites throughout the State. Measurements and observations of remnant scour made during low-flow discharges were used to record site conditions. These remnant-scour data were used to develop an observed streambed-scour index that provides a screening mechanism for ranking existing streambed scour. The observed- streambed-scour ranking values range from 10 (no observed scour) to 0 (pier[s] with pile[s] exposed). This index is based on the relative integrity of the substructure of each bridge with respect to observed scour. This observed-streambed-scour index was developed by use of qualitative criteria established with cooperative input from Indiana Department of Transportation and is intended as a screening tool to rank existing scour conditions. Numerous other factors that have not been included in this indexing scheme need to be considered when evaluations of overall bridge integrity are made.

Indiana↗

USGS1993

Efficient method for assessing channel instability near bridges

Efficient methods for data collection and processing are required to complete channel-instability assessments at 5,600 bridge sites in Indiana at an affordable cost and within a reasonable time frame while maintaining the quality of the assessments. To provide this needed efficiency and quality control, a data-collection form was developed that specifies the data to be collected and the order of data collection. This form represents a modification of previous forms that grouped variables according to type rather than by order of collection. Assessments completed during two field seasons showed that greater efficiency was achieved by using a fill-in-the-blank form that organizes the data to be recorded in a specified order: in the vehicle, from the roadway, in the upstream channel, under the bridge, and in the downstream channel.

Conference Paper↗

USGS1986

Natural flow and water consumption in the Milk River basin, Montana and Alberta, Canada

A study was conducted to determine the differences between natural and nonnatural Milk River streamflow, to delineate and quantify the types and effects of water consumption on streamflow, and to refine the current computation procedure into one which computes and apportions natural flow. Water consumption consists principally of irrigated agriculture, municipal use, and evapotranspiration. Mean daily water consumption by irrigation ranged from 10 cu ft/sec to 26 cu ft/sec in the Canada part and from 6 cu ft/sec to 41 cu ft/sec in the US part. Two Canadian municipalities consume about 320 acre-ft and one US municipality consumes about 20 acre-ft yearly. Evaporation from the water surface comprises 80% 0 90% of the flow reduction in the Milk River attributed to total evapotranspiration. The current water-budget approach for computing natural flow of the Milk River where it reenters the US was refined into an interim procedure which includes allowances for man-induced consumption and a method for apportioning computed natural flow between the US and Canada. The refined procedure is considered interim because further study of flow routing, tributary inflow, and man-induced consumption is needed before a more accurate procedure for computing natural flow can be developed. (Author 's abstract)

Water-Resources Investigations Report↗