REVISITING WATER QUALITY WITHIN THE BRIAR CREEK WATERSHED (COLUMBIA COUNTY, PA)

In October 2011, a year-long study of water quality was initiated in the Briar Creek watershed (Pfister, et al. 2012, 2013). During October of 2018, nine of the ten original sites, plus an additional site, were sampled to compare water chemistry. In situ data (pH, temperature, dissolved oxygen, and conductivity) were collected at each sampling location. In addition, water samples were collected and turbidity determined on site. Water samples were then transported back to the laboratory, and alkalinity and acidity were determined within six to nine hours utilizing filtered samples. Non-filtered and filtered samples were preserved for future analyses of selected cations and anions as well as selected metals on each. These results were compared with those of the 2011-12 study. Rather than compare our results to a year-long average, we compared our data to the results from the closest calendar day in the 2011-12 study. Values of alkalinity, acidity, conductivity, iron, and manganese were relatively high for site 9, while dissolved oxygen (% saturation) was low, consistent with data from 2011. Site 3 had relatively high values for iron and aluminum in the previous study conducted and this trend continued for data collected in this study. Site 5 was of interest in this study due to extensive modifications since the previous study. A riparian buffer system has been planted to mediate the effects of trampling by livestock belonging to the adjacent farm. Notable differences at that site from then to the present study are higher alkalinity, drastically reduced acidity, turbidity cut in half, total iron cut in half, and the approximately 125 ppb aluminum concentration reduced to below detectable limits. The other site that has been notably modified since 2011-12 is Site 3, where the bridge has been widened and replaced, but the only observable changes in water chemistry are differences in total iron. On the whole, the Briar Creek watershed chemistry has been fairly stable, at least within the parameters of this study.