Conductivity increased in Upper Ohio River Valley streams during the hot and dry summer of 2020

Abstract

As the climate begins to change, streams are faced with rising water temperatures and prolonged droughts. Droughts can lead to low flow and increases conductivity concentrations in streams, which can cause stressful events for organisms present. We collected water chemistry data at 24 sites over the summer months of 2019 and 2020 to see if there were any significant differences between the years. We sampled streams ranging in size from headwater to 8^th order and impairment ranging from biologically healthy to acid mine drainage (AMD) impacted. We found conductivity to be higher at all of our sites in 2020, while 14 of the 24 had warmer water temperatures. In our non-AMD sites, conductivity increased by 100 µS cm^-1 in 2020 posing increased stress for organisms present, while sites affected by AMD were always over 1,000 µS cm^-1. Rising temperature and increasing conductivity create challenges for sensitive species while more tolerant species become more dominant.