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Research about Pennsylvania

Source-linked reports with geographic coverage including Pennsylvania.

At least 559 records · Page 31Linked to original sources

Water quality investigation of Francis Slocum Lake, Luzerne County, Pennsylvania

This report summarizes water-quality data collected in the Francis Slocum Lake drainage basin, Pennsylvania, during an assessment from October 1976 to September 1977. Data were collected for nitrogen, phosphorus, carbon, and fecal coliform and fecal streptococcal bacteria. Results of the restricted sampling indicate that nutrient recycling within the lake is sufficient to support the periodic luxurient growth of algae and aquatic weeds. Inflows are not contributing high concentrations of nutrients to the ecosystem. Sampling for enteric bacteria indicate the sanitary quality is sufficiently high for water-contact recreation.

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Floods of July 19-20, 1977 in the Johnstown area, western Pennsylvania

Intense rainfall on the evening of July 19 and early morning hours of July 20, 1977, resulted in moderate to record flooding throughout much of an eight-county area of southwest Pennsylvania. In a 400-square-mile area directly north and east of Johnstown, rainfall totals of 6 to 12 inches were measured in a six to eight-hour period. Flood peaks having recurrence intervals greater than 100 years were recorded at several sites, primarily in the Conemaugh River basin. Runoff rates were as high as 2,390 cubic feet per second per square mile, in a 5.86-square-mile drainage area in the Little Conemaugh River basin. The Conemaugh River at Seward, which drains 715 square miles, had a peak discharge of 161 cubic feet per second per square mile. The flood waters claimed at least 78 lives and caused total losses in excess of $300 million. Also, seven earthfill dams, used mainly for water supply in the Johnstown area, failed. This report describes the storm and the associated flooding. A tabulation of peak gage heights and discharges for the July 1977 flood and for the maximum flood previously known is included for 57 sites. Data pertaining to the dams that failed are included also. (Woodard-USGS)

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Sediment discharge from highway construction near Port Carbon, Pennsylvania

The effects of highway construction on suspended-sediment loads were studied in the upper reaches of the Schuylkill River basin, Schuylkill County, Pennsylvania, from April 1975 to March 1977. From March 1975 to October 1976, 4.3 miles of State Route 209 was relocated through the upper reaches of the basin, a mountainous watershed with a drainage area of 27.1 square miles. About 16,000 tons of suspended-sediment was discharged from the basin during the construction. The highway construction produced about 8,000 tons or 50 percent of the total sediment discharge. Steep slopes, the availability of fine coal wastes, coal-washing operations, and other land uses in the basin were responsible for most of the remaining sediment discharge. Seventy percent of the total suspended-sediment discharge occurred during eight storms.

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Postimpoundment survey of water-quality characteristics of Raystown Lake, Huntingdon and Bedford Counties, Pennsylvania

Water-quality data, collected from May 1974 to September 1976 at thirteen sites within Raystown Lake and in the inflow and outflow channels, define the water-quality characteristics of the lake water and the effects of impoundment on the quality of the lake outflow. Depth-profile measurements show Raystown Lake to be dimictic. Thermal stratification is well developed during the summer. Generally high concentrations of dissolved oxygen throughout the hypolimnion during thermal stratification, low phytoplankton concentrations, and small diel fluctuations of dissolved oxygen, pH, and specific conductance indicate that the lake is low in nutrients, or oligotrophic. Algal assays of surface samples indicate that orthophosphate was a growth-limiting nutrient. The diatoms (Chrysophyta) were the dominant phytoplankton group found through-out the study period. The lake waters contained very low populations of zooplankton. Fecal coliform and fecal streptococcus densities measured throughout the lake indicated no potentially dangerous areas of water-contact recreation. The most apparent effect that the impoundment had on water quality was the removal of nutrients, particularly orthophosphate, through phytoplankton uptake and sediment deposition.

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Bacteriological water quality of Tulpehocken Creek basin, Berks and Lebanon Counties, Pennsylvania

A four month intensive study of the bacteriological quality of water in the Tulpehocken Creek basin indicates that (1) the streams locally contain high densities of bacteria indicative of fecal contamination, (2) nonpoint waste sources, particularly livestock, are the dominant influence in the excessive bacteriological-indicator counts observed, and (3) retention time of water in the proposed Blue Marsh Lake is believed sufficient to reduce bacteria densities to acceptable levels except following intense rainfall and runoff events during normally low flow periods.

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Geology and groundwater resources of northern Berks County, Pennsylvania

The area of investigation comprises approximately 540 square miles and lies entirely within the Great Valley section of the Valley and Ridge physiographic province. The Great Valley is underlain chiefly by carbon ate rocks in the south and by shale and graywacke in the north. Most of the carbonate rocks are included in two great nappes that differ appreciably in stratigraphic detail.

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Environmental geology, Allegheny County and vicinity, Pennsylvania: Description of a program and its results

Past land-use practices, including mining, in Allegheny County, Pa., have resulted in three principal environmental problems, exclusive of air and water contamination. They are flooding, landsliding, and subsidence over underground mines. In 1973, information was most complete relative to flooding and least complete relative to landsliding. Accordingly, in July 1973, the U.S. Geological Survey (USGS) and The Appalachian Regional Commission (ARC) entered into an agreement by which the USGS undertook studies chiefly aimed at increasing knowledge of landsliding and mine subsidence relative to land use, but having other ramifications as well, as part of a larger ARC 'Land-use and physical-resource analysis' (LUPRA) program. The chief geographic focus was Allegheny County, but adjacent areas were included in some investigations. Resulting products, exclusive of this report, are: 1. Forty-three provisional maps of landslide, distribution and susceptibility and of land modified by man in Allegheny County, 1:24,000 scale, 7½ -minute quadrangle format, released to open files. 2. Four USGS Miscellaneous Field Studies (MF) maps of Allegheny County showing (a) bedrock, MF685A; (b) susceptibility to landsliding, MF-685B ; (c) coal-mining features, MF-685C; and (d) zones that can be affected by flooding, landsliding and undermining, MF-685D; all at the scale of 1:50,000. 3. Two MF maps showing coal-mining activity and related information and sites of recorded mine-subsidence events, and one MF map classifying land surface by relative potentiality of mine subsidence, in Allegheny, Washington, and Westmoreland Counties, Pa., at a scale of 1:125,000--MF-693A through MF-693C. 4. A companion report to the Allegheny County map of susceptibility to landsliding--USGS Circular 728. 5. Five MF maps, largely in chart form, describing interaction of the shallow ground-water regime with mining-related problems, landsliding, heavy storm precipitation, and other features and processes, largely in Allegheny County--MF-641A through MF-641E. Map products are directly applicable to general classification of land for susceptibility to landsliding and mine subsidence and, to a lesser extent, flooding and engineering characteristics. The hydrogeologic charts enable greater understanding of environmental effects of ground water. All products are guides to expected conditions, but none are substitutes for detailed investigations of specific sites by competent technical personnel on the ground. Specific results and findings are: 1. Knowledge of .susceptibility to landsliding in Allegheny County now is adequate for application to countywide land-use planning. 2. About 110 mi 2 (285. km 2) , or 15 percent, of the county has some significant degree of susceptibility to landsliding. 3. Although a general classification of land in Allegheny, Washington, and Westmoreland Counties relative to mine-subsidence incidents was prepared, data are wholly inadequate for even moderately precise prediction of subsidence events over previously mined-out areas; the accumulation of adequate data might not repay the effort in terms of damage prevention. 4. Commonwealth-of-Pennsylvania regulations, have been very successful in limiting mine-subsidence damage over areas mined after 1966. 5. Undermining and consequent subsidence may have affected the ground-water regime more widely than heretofore believed. Except for the earth-disturbance inventory that resulted in the maps of susceptibility to landsliding and man-modified land, methods used in the studies largely were conventional. The inventory and ensuing analysis combined aerial photographic interpretation with field work and incorporation of existing data. The method worked very well for the purposes of defining distribution of landslides and areas having different susceptibilities to landsliding. However, if susceptibility to landsliding alone had been the goal, this could have been determined adequately by using photographs at smaller scales and appreciably less expenditure of effort per unit of ground area.

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Limnological studies of the major streams in Chester County, Pennsylvania

The major streams in Chester County, Pennsylvania were studied to determine their environmental state, and to relate this condition to land- use patterns. A biological numerical rating system on a scale of 1 to 10 was developed to classify stream conditions. One indicates extremely toxic conditions and 10 balanced biological conditions. The majority of the streams studied had ratings between 4 and 8, indicating they were experiencing varying degrees of enrichment and/or sediment deposition. The streams with high numerical ratings were generally found in rural and agricultural areas. Streams with low numerical rating were found mostly in areas near waste treatment facilities or industry. Large changes in the numerical rating of a stream were related to changes in land-use patterns. Relationships were developed between dissolved solids concentrations and the biological numerical ratings of the streams. Streams with ratings from 6 to 10 had dissolved solids concentrations of approximately 100 mg/L. At ratings of 5 to 1, the dissolved solids concentrations increased progressively from 122 to 310 mg/L. Chemical data for the streams were related to the dominant orders of benthic invertebrates. The stoneflies were found to be the most sensitive to high levels of chemical constituents. The trueflies, mayflies, and caddis flies showed a wide tolerance to various chemical constituents.

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Water loss from Jordan Creek near Allentown, Pennsylvania - 1973 to 1976

Results of water-loss studies for Jordan Creek near Allentown, Pa. are presented in both tabular and graphical form. The reach studied is approximately 24 miles long and extends from a point near Lowhill, Pa. to a point in Allentown, Pa. The drainage area at Allentown is about 76 square miles. In portions of the study area, Jordan Creek loses considerable parts of its flow to the permeable limestones and dolomites that it traverses. Seven current-meter measurements were made at each of ten sites along the reach, during the period 1973 to 1976. The results of the above measurements are analyzed and presented in a form suitable for use in planning the operation of a proposed reservoir which may be built near the upstream end of the reach. Three examples of how the results may be used are presented.

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Flow routing in the Susquehanna River Basin: Part I - Effects of Raystown Lake on the low-flow frequency characteristics of the Juniata and lower Susquehanna Rivers, Pennsylvania

A flow-routing model was used to simulate 17 water years of daily streamflows at five sites. The sites were Mapleton Depot and Newport, Pennsylvania, on the Juniata River, and Harrisburg and Marietta, Pennsylvania, and Conowingo, Maryland, on the Susquehanna River. The purpose for the simulations was to determine the effects of a new reservoir, Raystown Lake, on the low-flow frequency characteristics of these sites. Raystown Lake is on Raystown Branch Juniata River, a tributary to the Juniata River. Output from a reservoir-regulation model of Raystown Lake was used as input to the flow-routing models. In addition, a reservoir-routing model was developed for the hydroelectric power dams on the lower Susquehanna River. Low-flow frequency curves, based on the post-Raystown Lake simulated flows, were compared to similar curves based on pre-Raystown observed data. The comparison indicated that operation of the lake will cause estimated increases in the 7-day 10-year low flows ranging from 420 cfs at Mapleton Depot to 290 cfs at Marietta and Conowingo over the 7-day 10-year low flows for pre-Raystown conditions. Although inherent modeling errors exist in all of these simulated data, the overall quality of the simulated flows and the low-flow frequency curves is considered good. (Woodard-USGS)

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Water-quality study of Tulpehocken Creek, Berks County, Pennsylvania, prior to impoundment of Blue Marsh Lake

Blue Marsh Lake is planned as a multipurpose impoundment to be constructed on Tulpehocken Creek near Bernville, Berks County, Pennsylvania. Prior to construction, samples of water, bed material, and soil were collected throughout the impoundment site to determine concentrations of nutrients, insecticides, trace metals, suspended sediment, and bacteria. Analyses of water suggest the Tulpehocken Creek basin to be a highly fertile environment. Nitrogen and phosphorus concentrations near the proposed dam site had median values of 4.5 and 0.13 mg/L, respectively. Suspended sediment discharges average between 100 and 200 tons (90.7 to 181.4 metric tons) per day during normal flows but may exceed 10,000 tons (9,070 metric tons) per day during storm runoff. Highest yields were measured during winter and early spring. Concentrations range from 3 mg/L to more than 500 mg/L. Bed material samples contain trace quantities of aldrin, DDT, DDD, DDE, dieldrin, and chlordane. Polychlorinated biphyenyls (PCB's) ranged from 10 to 100 μg/kg. Soils at the impoundment site are of average fertility. However, the silt loam texture is ideal for attachment and growth of aquatic plants. Bacteria populations indicative of recent fecal contamination are prevalent in the major inflows to the proposed lake. Fecal Coliform exceeded the standards recommended by the Federal Water Pollution Administration Committee on Water Quality Criteria for public water supply in 29 percent of the monthly samples, and exceeded the recommended public bathing waters standard in 83 percent of the samples collected from June to September. Arsenic from an industrial waste was found in the water, suspended sediment, and bed material of Tulpehocken Creek in concentrations of 0 to 30 μg/l, 2 to 879 μg/l, and 1 to 79 μg/g, respectively. It represents a potential environmental hazard; however, the measured concentrations are less than that known to be harmful to man, fish, or wildlife, according to published water quality criteria.

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