Algal Growth Potentials and Heavy Metal Concentrations of the Primary Streams to Upper Beaver Lake
Meyer and Green (1984) demonstrated the probable inhibition of algal growth potential by heavy metals in upper Beaver Lake. Upper Beaver Lake receives water from three tributaries. One contains a small reservoir and the combined streams receive sewage input. Collections were made approximately monthly at eight sites for the Algal Assay Bottle Test (AABT) and heavy metal analysis. In general, AABT results indicated that the collections above the sewage input were phosphorus limited while those below were nitrogen or combined nitrogen and phosphorus limited. Growth inhibition occurred during summer and early fall at various sites with greater inhibition at the confluence of the streams. No inhibitions occurred at the site below the sewage input. Heavy metal concentrations had an overall tendency to increase downstream. Values within the small reservoir were 50-100% higher than in the feeder stream. Highest values of Pb were observed below the reservoir. SO4, CI, Mg, Ca, Na and K had high values during low flow in August- October. The low values were independent of high flow. Pb followed an independent pattern. Storm event results showed that the Ca maximum was before the hydrographic peak while Fe, Mn, Pb, Zn, Co, Ni, Cu and Cd attained their maximum just after the peak. Maximum values were 4-10 times background values. Mn, P and Fe exceeded EPA recommended standards for drinking water.