Water quality of the Upper West Branch Susquehanna River and tributary streams between Curwensville and Renovo, Pennsylvania, May and July 1984

Abstract

The soils and rocks of the Upper West Branch Susquehanna River basin, from its headwaters downstream for 150 miles, are laden with pyritic materials that have the potential to produce acid mine drainage. The effects of mine drainage are severe, particularly in the reach between Curwensville and Renovo where present water quality cannot support viable populations of benthic macroinvertebrates or fish. During base-flow periods in May and July 1984, streamflow and water quality were measured at four sites on the West Branch Susquehanna River and near the mouths of 94 tributaries. Water-quality constituents determined were temperature, specific conductance, pH, acidity, alkalinity, and concentrations of dissolved sulfate and the total and dissolved forms of iron, manganese, aluminum, and zinc. The data collected for the study indicate that the predominant influence on water quality of the tributaries is land use. An area where few or no coal deposits or disturbed area were present was found to have relatively good surface-water quality (median pH was nearly 5.5 units), whereas areas where coal mining was active in the basin, or where large areas of unreclaimed mines were present, were found to have poorest water quality (median pH was generally less than 4.0 units). In general, Moshannon, Sinnemahoning, Clearfleld, and Kettle Creeks were found to be the largest tributary sources of acidity and total-recoverable iron to the river. During the May sampling, Moshannon, Sinnemahoning, and Clearfield Creeks contributed 63 percent of the 365 tons/day of acidity, and Moshannon and Clearfield Creeks contributed 76 percent of the 44.8 tons/day of totalrecoverable iron that were discharged to the river. During the July sampling, Moshannon, Kettle, and Clearfleld Creeks contributed 60 percent of the 131 tons/day of acidity, and Moshannon and Kettle Creeks contributed 51 percent of the 6.5 tons/day of totalrecoverable iron discharged to the river. The West Branch Susquehanna River was found to have pH ranging from 5.4 to 6.5 units and specific conductance ranging from 267 to 310 fiS/cm (microsiemens per centimeter at 25 degrees Celsius) at the most upstream site at Curwensville. The water quality was most degraded at the site at Karthaus (pH 3.9 to 4.1 units, specific conductance 330 to 610fiS/cm). Quality gradually improved downstream to the site at Renovo (pH 3.8 to 4.6 units, specific conductance 200 to 392^8/cm), although the quality did not recover to that found at Curwensville. INTRODUCTION The area drained by the Upper West Branch Susquehanna River, from its headwaters downstream for 150 mi (miles), has undergone substantial surface mining for coal. The soils and rocks disturbed by mining are laden with pyritic materials that have the potential to produce acid mine drainage. The effects of mine drainage are severe, particularly in the reach between Curwensville and Renovo (fig. 1), where present water quality cannot support viable populations of benthic macroinvertebrates or fish. According to a report by the Pennsylvania Department of Environmental Resources (PaDER)(1981), the acid mine drainage also is responsible for masking other forms of water pollution. Because of the general inaccessibility of the river between Curwensville and Renovo, little is known about the water quality of the numerous small tributaries and their effect on the water quality of the river.