The Pennsylvania Department of Environmental Protection has announced that since October levels of total dissolved solids, or TDS have dropped well below state and federal guidelines. In October the DEP discovered high levels of TDS in the Monongahela river. The high levels of TDS were detected between the West Virginia border and the confluence in Pittsburgh. The DEP said the high levels were because of low precipitation and run off from mines. The TDS levels have been tested for three weeks at well below the levels outlined by the DEP.
Total dissolved solids in water does not pose a known health risk but can make water look, smell and taste differently. Normally solids such as carbonates, chlorides, sulfates, nitrates, sodium, potassium, calcium and magnesium are found dissolved in the water. The limit for TDS is set at 500 parts per million. In December levels were tested at 110 ppm to 196 ppm as opposed to October levels that reached as high as 908 ppm in some parts of the river.