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Research about Lancaster County, Pennsylvania

Source-linked reports with geographic coverage including Lancaster County, Pennsylvania.

8 recordsLinked to original sources
USGS2020

Effects of legacy sediment removal and effects on nutrients and sediment in Big Spring Run, Lancaster County, Pennsylvania, 2009–15

Big Spring Run is a 1.68-square mile watershed underlain by mostly carbonate rock in a mixed land-use setting (part agricultural and part developed) in Lancaster County, Pennsylvania. Big Spring Run is a subwatershed of Mill Creek, a tributary to the Conestoga River. These watersheds are known contributors of nutrient and sediment loads to the Chesapeake Bay and several stream reaches are on the Pennsylvania impaired waters list. Big Spring Run is listed as impaired and was selected by the Pennsylvania Department of Environmental Protection to evaluate a novel best management practice to restore natural aquatic ecosystems by removing legacy sediment. The study was designed to quantify sediment and nutrient contributions in pre- and postrestoration periods (water years 2009–11 and 2012–15, respectively) using an intensive monitoring approach at three surface-water sites within the watershed. Instrumentation at each site continuously measured (15-minute intervals) streamflow, water temperature, and turbidity. Water-quality samples were collected routinely (generally monthly and during selected storms); sampling frequency varied by site and constituent at the three monitoring sites. Effects of legacy sediment removal and restoration on nutrient concentrations varied in surface water samples depending on the form (particulate, dissolved, organic, inorganic). For example, total phosphorus concentrations at the downstream site decreased from a median of 0.19 milligram per liter (mg/L) to 0.04 mg/L, pre- and postrestoration periods, respectively. Concentrations of orthophosphate, the dissolved form of phosphorus, were not significantly different pre- to postrestoration at the downstream site. Similarly, nitrate concentrations, the dominant form of nitrogen in Big Spring Run surface-water samples (92.3 percent of total nitrogen) were not significantly different in the pre- compared to the postrestoration periods. Legacy sediment removal and restoration had significant effects on suspended-sediment concentrations and loads. Median suspended-sediment concentrations at the downstream site decreased from 556 mg/L prerestoration to 74 mg/L postrestoration even though streamflow hydrographs during the two periods were similar. In the postrestoration period, the mean annual suspended-sediment load conveyed to the restoration area from the upstream sites was 839 tons, whereas mean annual suspended-sediment load at the downstream site was reduced to 242 tons. Streamflow during storms transports a large proportion of the suspended-sediment load; there were a total of 320 storms over the study period. In Big Spring Run, a single storm event can transport more than 25 percent of the annual suspended-sediment load. The greatest single-storm contribution to suspended-sediment load was 38 percent in water year 2015 at the downstream site. Although streamflow magnitudes during storms varied greatly over the study period, median streamflow was 17.5 cubic feet per second and median duration was about 3 hours and 24 minutes. Results observed for this study using the newly proposed best management practice were compared with other best management practices intended to reduce sediment. For example, during a previous study, statistically significant reductions in suspended-sediment concentration were observed when streambank fencing was implemented in an adjacent watershed; however, suspended-sediment reductions were an order of magnitude less than the reductions observed in the current study. Median suspended-sediment concentration at the downstream site was reduced by 482 mg/L in the current study compared to only 30 to 46 mg/L as a result of streambank fencing.

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USGS2006

Effects of Streambank Fencing of Near-Stream Pasture Land on a Small Watershed in Lancaster County, Pennsylvania

This study indicated that a small buffer width along a stream in pasture land can have a positive influence on surface-water quality, benthic macroinvertebrates, and near-stream shallow ground-water quality. Overland runoff processes that move suspended sediment to the stream were controlled (or reduced) to some extent by the vegetative buffer established. Results indicated streambank fencing resulted in decreases in N-species, total-P, and suspended-sediment concentrations and yields at the outlet of the treatment basin relative to untreated sites; however, dissolved-P concentrations and yields increased. These results indicate that nutrient management, in conjunction with streambank fencing, is important in helping to control nutrient loadings to streams in this agricultural setting. An upstream site (T-2) in the treatment basin showed post-treatment reductions in suspended-sediment yields and increases in N and P yields. The different results for these treated sites indicates the effects of streambank fencing should be studied at as large a scale as possible because field-scale influences on water quality as drainage area decreases can mute the effects of fencing. Benthic-macroinvertebrate data indicated streambank fencing had a positive influence on benthic macroinvertebrates and their habitat. More improvement was detected at the outlet of the treatment basin than the upstream sites. Probably the most important biological metric, taxa richness, indicated a greater number of benthic-macroinvertebrate taxa at treated relative to control sites after fencing. Results indicated fencing improved shallow ground-water quality (for the well nest in a stream-gaining area), as noted by decreased concentrations of N species and fecal-streptococcus counts. This improvement only occurred at the well nest where the stream was gaining water from the shallow ground-water system.

Pennsylvania↗
USGS2006

Effects of streambank fencing of pasture land on benthic macroinvertebrates and the quality of surface water and shallow ground water in the Big Spring Run basin of Mill Creek watershed, Lancaster County, Pennsylvania, 1993-2001

Streambank fencing along stream channels in pastured areas and the exclusion of pasture animals from the channel are best-management practices designed to reduce nutrient and suspended-sediment yields from drainage basins. Establishment of vegetation in the fenced area helps to stabilize streambanks and provides better habitat for wildlife in and near the stream. This study documented the effectiveness of a 5- to 12-foot-wide buffer strip on the quality of surface water and near-stream ground water in a 1.42-mi2 treatment basin in Lancaster County, Pa. Two miles of stream were fenced in the basin in 1997 following a 3- to 4-year pre-treatment period of monitoring surface- and ground-water variables in the treatment and control basins. Changes in surface- and ground-water quality were monitored for about 4 years after fence installation. To alleviate problems in result interpretation associated with climatic and hydrologic variation over the study period, a nested experimental design including paired-basin and upstream/downstream components was used to study the effects of fencing on surface-water quality and benthic-macroinvertebrate communities. Five surface-water sites, one at the outlet of a 1.77-mi2 control basin (C-1), two sites in the treatment basin (T-3 and T-4) that were above any fence installation, and two sites (one at an upstream tributary site (T-2) and one at the outlet (T-1)) that were treated, were sampled intensively. Low-flow samples were collected at each site (approximately 25-30 per year at each site), and stormflow was sampled with automatic samplers at all sites except T-3. For each site where stormflow was sampled, from 35 to 60 percent of the storm events were sampled over the entire study period. Surface-water sites were sampled for analyses of nutrients, suspended sediment, and fecal streptococcus (only low-flow samples), with field parameters (only low-flow samples) measured during sample collection. Benthic-macroinvertebrate samples were collected in May and September of each year; samples were collected at the outlet of the control and treatment basins and at three upstream sites, two in the treatment basin and one in the control basin. For each benthic-macroinvertebrate sample: Stream riffles and pools were sampled using the kick-net method; habitat was characterized using Rapid Bioassessment Protocols (RBP); water-quality samples were collected for nutrients and suspended sediment; stream field parameters were measured; and multiple biological metrics were calculated. The experimental design to study the effects of fencing on the quality of near-stream shallow ground water involved a nested well approach. Two well nests were in the treatment basin, one each at surface-water sites T-1 and T-2. Within each well nest, the data from one deep well and three shallow wells (no greater than 12 ft deep) were used for regional characterization of ground-water quality. At each site, two of the shallow wells were inside the eventual fence (treated wells); the other shallow well was outside the eventual fence (control well). The wells were sampled monthly, primarily during periods with little to no recharge, for laboratory analysis of nutrients and fecal streptococcus; field parameters of water quality also were measured.

Pennsylvania↗
USGS1998

Evaluation of geophysical logs and video surveys in boreholes adjacent to the Berkley Products Superfund Site, West Cocalico Township, Lancaster County, Pennsylvania

Between February 1998 and April 1998, geophysical logs were collected in nine boreholes adjacent to the Berkley Products Superfund Site, West Cocalico Township, Lancaster County, Pa. Video surveys were conducted on four of the nine boreholes. The boreholes range in depth from 320 to 508 feet below land surface, are completed open holes, have ambient vertical flow of water, and penetrate a series of interbedded siltstone, sandstone, and conglomerate units. The purpose of collecting geophysical-log data was to help determine horizontal and vertical distribution of contaminated ground water migrating from known or suspected sources and to aid in the placement of permanent borehole packers. The primary contaminants were derived from paint waste that included pigment sludges and wash solvents. The chlorinated volatile organic compounds probably originated from the wash solvents. Caliper logs and video surveys were used to locate fractures; inflections on fluid-resistivity and fluid-temperature logs were used to locate possible water-bearing fractures. Heatpulse-flowmeter measurements were used to verify the locations of water-producing or water-receiving zones and to measure rates of flow between water-bearing fractures. Single-point-resistance and natural-gamma logs provided information on stratigraphy. After interpretation of geophysical logs, video surveys, and driller's logs, permanent multiple-packer systems were installed in each borehole to obtain depth specific water samples from one or more water-bearing fractures in each borehole.

Pennsylvania↗