Development of an algal bioassessment tool for freshwater streams in South Carolina

In the early 1970s, the South Carolina Department of Health and Environmental Control (SC DHEC) began what is today a very strong bioassessment program. Although a fish Index of Biotic Integrity (IBI) has been developed, phytoplankton is routinely collected and benthic diatoms were previously collected, the vast majority of stream bioassessments conducted by SC DHEC have been related to the benthic macroinvertebrate program. As many other government agencies and researchers have realized, a robust bioassessment program relies on a multi-assemblage approach. For this reason, SC DHEC is developing a benthic algal bioassessment program for freshwater streams. Methods employed, as well as the results of the first field season, will be presented. In addition, our development of a diatom-based IBI, tailored to the ecoregions within South Carolina, will be discussed.