Search USGSSearch

Geology topics

Lloyd A. Reed

Publications and source records attributed to Lloyd A. Reed.

14 recordsLinked to original sources

Prediction of velocities for a range of streamflow conditions in Pennsylvania

A regression equation that is used nationwide to predict traveltime in streams during periods of low and moderate flow was developed by H.E. Jobson in 1996. Because none of the data used in the development of the equation were from streams in Pennsylvania, velocities for low and moderate flows predicted by the equation were compared to velocities measured during time-of-travel studies on the Susquehanna, Delaware, and Lehigh Rivers. Although these comparisons showed good agreement, a similar comparison using velocities for higher flows indicated an overestimate by this regression equation. Because of the need for a method of computing traveltimes for periods of high flows, a new regression equation was developed using data from three sources: (1) time-of-travel studies conducted at low and moderate flow, (2) slop-area measurements of flood flows, and (3) velocities of the 100-year floodway as reported in various flood-insurance studies. The new regression equation can be used for predicting velocities associated with flows up to the 100-year flood for Pennsylvania streams. It has standard errors of estimate of 0.18 feet per second, 0.37 feet per second; and 0.31 feet per second, for time-of-travel studies in the Susquehanna, Delaware, and Lehigh Rivers, respectively. The standard error of estimate is 1.71 feet per second for velocities determined from the slope-area measurements and 1.22 feet per second for velocities determined from the flood-insurance studies.

Water-Resources Investigations Report

Techniques for estimating magnitude and frequency of peak flows for Pennsylvania streams

Regression equations for estimating the magnitude and frequency of floods on ungaged streams in Pennsylvania with drainage areas less that 2,000 square miles were developed on the basis of peak-flow data collected at 313 streamflow-gaging stations. All streamflow-gaging stations used in the development of the equations had 10 or more years of record and include active and discontinued continuous-record and crest-stage partial-record streamflow-gaging stations. Regional regression equations were developed for flood flows expected every 10, 25, 50, 100, and 500 years by the use of a weighted multiple linear regression model. The State was divided into two regions. The largest region, Region A, encompasses about 78 percent of Pennsylvania. The smaller region, Region B, includes only the northwestern part of the State. Basin characteristics used in the regression equations for Region A are drainage area, percentage of forest cover, percentage of urban development, percentage of basin underlain by carbonate bedrock, and percentage of basin controlled by lakes, swamps, and reservoirs. Basin characteristics used in the regression equations for Region B are drainage area and percentage of basin controlled by lakes, swamps, and reservoirs. The coefficient of determination (R 2 ) values for the five flood-frequency equations for Region A range from 0.93 to 0.82, and for Region B, the range is from 0.96 to 0.89. While the regression equations can be used to predict the magnitude and frequency of peak flows for most streams in the State, they should not be used for streams with drainage areas greater than 2,000 square miles or less than 1.5 square miles, for streams that drain extensively mined areas, or for stream reaches immediately below flood-control reservoirs. In addition, the equations presented for Region B should not be used if the stream drains a basin with more than 5 percent urban development.

Water-Resources Investigations Report

Comparison of methods for computing streamflow statistics for Pennsylvania streams

Methods for computing streamflow statistics intended for use on ungaged locations on Pennsylvania streams are presented and compared to frequency distributions of gaged streamflow data. The streamflow statistics used in the comparisons include the 7-day 10-year low flow, 50-year flood flow, and the 100-year flood flow; additional statistics are presented. Streamflow statistics for gaged locations on streams in Pennsylvania were computed using three methods for the comparisons: 1) Log-Pearson type III frequency distribution (Log-Pearson) of continuous-record streamflow data, 2) regional regression equations developed by the U.S. Geological Survey in 1982 (WRI 82-21), and 3) regional regression equations developed by the Pennsylvania State University in 1981 (PSU-IV). Log-Pearson distribution was considered the reference method for evaluation of the regional regression equations. Low-flow statistics were computed using the Log-Pearson distribution and WRI 82-21, whereas flood-flow statistics were computed using all three methods. The urban adjustment for PSU-IV was modified from the recommended computation to exclude Philadelphia and the surrounding areas (region 1) from the adjustment. Adjustments for storage area for PSU-IV were also slightly modified. A comparison of the 7-day 10-year low flow computed from Log-Pearson distribution and WRI-82- 21 showed that the methods produced significantly different values for about 7 percent of the state. The same methods produced 50-year and 100-year flood flows that were significantly different for about 24 percent of the state. Flood-flow statistics computed using Log-Pearson distribution and PSU-IV were not significantly different in any regions of the state. These findings are based on a statistical comparison using the t-test on signed ranks and graphical methods.

Water-Resources Investigations Report

Sediment deposition in Lake Clarke, Lake Aldred, and Conowingo Reservoir, Pennsylvania and Maryland, 1910-93

The Susquehanna River carries a significant amount of the sediment and the nutrient load transported to the Chesapeake Bay. Three large hydroelectric dams are located near the mouth of the Susquehanna River. The three dams and associated reservoirs are Safe Harbor (Lake Clarke) and Holtwood (Lake Aldred) in southern Pennsylvania and Conowingo (Conowingo Reservoir) in northern Maryland. Two of these reservoirs, Lakes Clarke and Aldred, have reached a state of equilibrium with sediment transport in the river. The third, Conowingo Reservoir, continues to accumulate sediment as well as particulate organic nitrogen and particulate phosphorus. Bottom-elevation surveys of Conowingo Reservoir made in 1959, 1990, and 1993 indicate that the reservoir will reach equilibrium with sediment transport of the river during the next 10 to 20 years. Data collected from 1985-89 indicate that the Susquehanna River transports about 1,780 million pounds of sediment, 147 million pounds of nitrogen, and 5.1 million pounds of phosphorus to the Chesapeake Bay during a year of normal streamflow. Once equilibrium is reached in the Conowingo Reservoir, these loads may increase to levels currently transported by the river to the reservoirs, about 6,600 million pounds of sediment, 153 million pounds of nitrogen, and 9.1 million pounds of phosphorus per year. These higher loads may effect progress made on reducing nutrient loads and should be considered when planning future programs.

Maryland, Pennsylvania

Herbicide concentrations in and loads transported by the Conestoga River and Pequea Creek, Lancaster County, Pennsylvania, 1992-95

Water samples were collected from four streams in Lancaster County from 1992 through 1995 and analyzed for selected herbicides. Samples were collected from the Little Conestoga Creek near Churchtown, Mill Creek (a tributary to the Conestoga River) at Elshelman Mill Road near Lyndon, the Conestoga River at Conestoga, and Pequea Creek at Martic Forge. Most samples were collected from stormflow that occurred during the growing season. Samples were analyzed for alachlor, aldrin, atrazine, chlordane, cyanazine, dieldrin, malathion, metolachlor, propazine, simazine, and toxaphene. Most samples had detectable concentrations of alachlor, atrazine, metolachlor, and simazine, and the loads of these constituents that were transported during each of the 4 years were computed. Of the samples collected from each of the streams—Little Conestoga Creek, Mill Creek, Conestoga River, and Pequea Creek—10, 12, 15, and 18 percent, respectively, had atrazine concentrations greater than 3.0 micrograms per liter, the U.S. Environmental Protection Agency maximum contaminant level. Loads of atrazine, metolochlor, and simazine were greater than loads of any other herbicides. The largest loads were transported during 1994. Loads of atrazine transported by the four streams during periods of storm- flow from May to September 1994 totaled 3.46, 28.3, 263, and 46.8 pounds, respectively. The total loads of atrazine transported by the four streams?Little Conestoga Creek, Mill Creek, Conestoga River, and Pequea Creek—during calendar year 1994 were 6.48, 54.1, 498, and 102 pounds, respectively. A little less than half the atrazine load transported by each stream—45, 39, 42, and 42 percent, respectively—was transported during storms that occurred from May through September. Average annual yields of atrazine for the period 1992-95 were 0.59, 0.64, 0.68, and 0.51 pounds per square mile from the Little Conestoga Creek, Mill Creek, Conestoga River, and Pequea Creek, respectively. Average annual yields of simazine were 0.36, 1.2, 0.54, and 0.48 pounds per square mile, respectively, and average annual yields of metolachlor were 0.46, 0.49, 0.54, and 0.31 pounds per square mile, respectively. Less than 1 percent of both the atrazine and metolachlor that was applied to all basins was transported by streamflow.

Water-Resources Investigations Report

Effects of strip mining the abandoned deep Anna S Mine on the hydrology of Babb Creek, Tioga County, Pennsylvania

Daylighting (strip mining of coal seams previously deep mined) operations are being conducted on the Anna S Mine, that underlies about 850 acres that are drained by three major discharges. The Hunter Drift drains an underground area of about 400 acres, the Anna S 1 main entry, an area of 330 acres, and Mitchel 2 discharge an area of about 120 acres. As of August 1, 1979, about 55 acres (15%) had been daylighted in the Hunter Drift basin, about 15 acres (5%) in the Anna S main entry basin and about 30 acres (25%) in the Mitchel basin. The acidity of the Mitchel 2 discharge changed the most, from 176 milligrams per liter (as CaCO3) in 1975-76 to 1,190 in 1978-79, an increase of 580%. The acidity of the Hunter Drift discharge increased from 348 milligrams per liter during 1975-76 to 710 milligrams per liter during 1978-79, an increase of 100%. The acidity of Anna S 1 increased about 45%.

Pennsylvania

Suspended-sediment discharge in five streams near Harrisburg, Pennsylvania, before, during, and after highway construction

Rainfall, streamflow, sediment, and turbidity data were collected as part of a study to evaluate the effects of highway construction on suspended-sediment discharges in streams. The study was also designed to evaluate the effectiveness of different erosion-control measures in reducing sediment discharge. Although highway construction increased suspended-sediment discharges from two to four-fold, the rate of sediment discharge quickly returned to pre-construction levels when construction ended. The most effective sediment control evaluated was offstream ponds, which were designed to trap and store sediment laden water from the construction area. The offstream ponds trapped about 70 percent of the sediment that reached them during most storms. Seeding and mulching generally reduced sediment loads about 20 percent. Rock dams and bales reduced loads about 5 percent. An onstream pond, constructed on a large stream below the construction area, reduced sediment loads about 80 percent. However, unlike the offstream ponds, which stopped discharging runoff water soon after precipitation ended, the onstream pond kept discharging runoff water, and the stream below the pond remained turbid for extended periods.

Water Supply Paper

Sediment characteristics of five streams near Harrisburg, Pennsylvania, before highway construction

Rainfall, streamflow, sediment, and turbidity data are being collected as part of a study to evaluate the effects of highway construction on sediment discharge. The study is also designed to determine the effectiveness of different erosion-control measures in reducing sediment discharges. The study area, near Enola, Pa., consists of five adjacent drainage basins, four of which will be crossed by Interstate 81. Ninety percent of the land in each of the basins is in forest or grass. Active farmland accounts for less than 10 percent, and the remainder is in roadways and buildings. The major factor affecting sediment concentrations and discharges was the construction of a one-lane roadway and a 5-acre (2 hm2) farm pond in basin 2. Approximately 100 tons (90 t) of sediment was discharged by the stream as a result of the roadway and pond construction.

Water Supply Paper

Hydrology and sedimentation of Bixler Run Basin, central Pennsylvania

Rainfall, streamflow, stream chemical, and sediment discharge data were collected from Bixler Run near Loysville, Pa., during the period from February 1954 to September 1969 as part of a project to evaluate sediment discharge from an agricultural area in which soil-conservation techniques were being adopted at a moderate rate. The study was conducted by the U.S. Geological Survey in cooperation with the Pennsylvania Department of Environmental Resources, State Conservation Commission. Sediment yields from the basin averaged 64 tons per square mile (22 tonnes per square kilometre) per year, approximately 25 percent less than yields from the surrounding area. The relation between water discharge and suspended-sediment discharge remained constant during the study. Suspended-sediment concentrations in the streamflow were less than 10 milligrams per litre 70 percent of the time. The concentration of chloride ions in the streamflow increased from 1959 to 1969. Ground water maintained flows at the gaging location at a rate of 1.9 cubic feet per second (0.054 cubic metres per second) during the period of data collection.

Water Supply Paper

Occurrence of pesticide residues in four streams draining different land-use areas in Pennsylvania

Samples of water, bed material, fish, and soil were collected in four small drainage basins in Pennsylvania in 1969-71 and analyzed to determine the concentrations of chlorinated-hydrocarbon insecticides. Water samples only were also analyzed for phenoxy-acid herbicides. Each basin studied represents a predominant land-use classification—forested, general farming, residential, and orchard farming. All water and fish samples showed pesticide concentrations less than the U.S. Public Health Service's (1969) recommended maximum permissible concentration. However, no fish were found in the orchard area stream at the time collection was attempted. DOT or one of its metabolites was the most frequently occurring insecticide and was detected in all media sampled except the forestedarea soil. The highest observed combined concentration of DOT and its metabolites in storm-runoff samples was 11.4 micrograms per litre in a sample collected from the residential area stream, but the median was higher (0.12 microgram per litre) in the orchard area than in the residential area (0.02 microgram per litre). A sample of the top 0.5 inch (13 millimetres) of orchard soil contained 40,000 micrograms per kilogram of DOT and its metabolites, even though DOT had not been used in the orchards for several years prior to this study. Maximum concentrations detected in other orchard media are 330 micrograms per kilogram in bed material and 3.45 micrograms per litre in storm runoff. Dieldrin was the second most frequently occurring insecticide. Other insecticides detected were chlordane, heptachlor epoxide, lindane, and a trace of aldrin in one fish sample. At least one of the following herbicides—2,4-D, silvex, or 2,4,5-T—was detected in each stream.

Water-Resources Investigations Report

Sediment characteristics of five streams near Harrisburg, Pa., before highway construction

Rainfall, streamfiow, sediment, and turbidity data are being collected as part of a study to evaluate the effects of highway construction on sediment discharge. The study is also designed to determine the effectiveness of different erosion-control measures in reducing sediment discharges. The study area, near Enola, Pa., consists of five adjacent drainage basins, four of which will be crossed by Interstate 81. Ninety percent of the land in each of the basins is in forest or grass. Active farmland accounts for less than 10 percent, and the remainder is in roadways and buildings. The major factor affecting sediment concentrations and discharges was the construction of a one-lane roadway and a 5-acre (2 hm 2 ) farm pond in basin 2. Approximately 100 tons (90 t) of sediment was discharged by the stream as a result of the roadway and pond construction.

Pennsylvania

Appraisal of stream sedimentation in the Susquehanna River basin

The Susquehanna River presently transports about 3.0 million tons of sediment annually (110 tons per square mile). Only about 1.8 million tons of sediment enters the head of Chesapeake Bay annually because some sediment is trapped behind the power dams on the lower Susquehanna. Measured annual sediment yields from subbasins in the Susquehanna range from 40 to 440 tons per square mile. The highest yields are from parts of the glaciated section of the basin, in the anthracite coal region, and the Piedmont province. The lowest yields are from parts of the glaciated section of the basin and the Appalachian high plateau. Available data indicate that there has been a downward trend of sediment discharge in recent years. In the future, the high sediment yields associated with urbanization may offset this present downward trend.

Susquehanna River

Effects of roadway and pond construction on sediment yield near Harrisburg, Pennsylvania

This report shows the effects that the construction of half a mile of one-lane roadway during June, July, and August 1970 and construction of a 5-acre pond during August and September 1970, had on sediment concentrations and sediment discharge of a stream draining an area of 0.76 square mile. The effects of the construction are shown by comparing the data collected from the affected basin with data collected from a similar adjacent basin, unaffected by construction. During the pond construction, base-flow sediment concentrations increased from the expected 6 mg/1 (milligrams per liter) to an average of 35 mg/l. Sediment discharge during June through December 1970 attributable to the construction was 55 tons, two-thirds of the amount normally expected during a year.

Pennsylvania

Hydrology and sedimentation of Corey Creek and Elk Run basins, north-central Pennsylvania

Analysis of data collected from two small agricultural basins in northcehtral Pennsylvania during the period May 1954 to September 1967 indicates that conservation measures reduced the quantity of suspended sediment leaving the Corey Creek basin as a result of frequent storms during the growing season. Extensive soil conservation treatments were applied in the 12.2-squaremile Corey Creek basin, but only minor treatments were applied in the adjacent 10.2-square-mile Elk Run basin. These treatments included the construction of ponds and diversion terraces and altering land use by such measures as establishing permanent hay land and changing marginal pasture land to wood lands. Elk Run basin, which is topographically and hydrologically similar to the Corey Creek basin, was used as an external control to assist in detecting and evaluating the hydrologic changes in Corey Creek. Trend analyses of data from both basins indicate a 47-percent decrease in sediment discharge from Corey Creek during the frequent storms that occur in the May to October growing season. Six percent of the sediment discharged from Corey Creek during the period of this investigation (1954-67) was discharged during these frequent growing-season storms. The remaining 94 percent of the sediment was discharged during the November to April dormant season and during two major events during the growing season, one October 1955 and one May 1961. No decrease in sediment discharge was observed for these events or for this period. The adjacent basin of similar size, topography, and hydrologic characteristics, Elk Run, was not scheduled for extensive conservation treatment; it was selected as a control for this study "because of the assumption that any changes in precipitation and runoff patterns would affect both basins in a similar manner. Rainfall, runoff, sediment, and stream-channel data are used in this report to estimate the probable hydrologic behavior of the Corey Creek basin provided the intensive conservation program had not been undertaken.~

Water Supply Paper