Columbia Water continues to proactively sample for perfluorinated compounds in its drinking water every six months. April 2021, samples show PFAS levels varying slightly from earlier test results in both the Canal Water Treatment Plant and Lake Murray Water Treatment Plant raw and finished water, with levels continuing to be well below the EPA health advisory targets.
Summary: The City of Columbia collected finished drinking water samples from each of its two water plants on April 20, 2021 utilizing the same parameters as DHEC sampling that occurred in June of 2020. The City also collected samples from each of its two source waters, the Columbia Canal and Lake Murray, and had those samples analyzed for the same 29 compounds using a third testing method.
Finished Drinking Water Sample Results: April, 2021 finished drinking water samples showed mixed results at the two water treatment plants with some levels going up, and others going down. Combined levels of PFOA and PFOS were 14.54 and 15.3 parts per trillion (ppt) for the two testing methods in the Canal Plant samples, and 13.17 and 7.29 ppt for the two testing methods in the Lake Plant samples, all well below the 70 ppt health advisory level. Only nine of the 29 compounds tested for have been detected in the finished water from each plant. There are no health advisories for any of the compounds detected other than PFOA and PFOS.
Source Water Sample Results: One new compound appeared at a very low level in the source water samples for the Canal Water Treatment Plant, which means 15 of the 29 PFAS compounds tested have been detected in one or both of the Columbia Canal and Lake Murray source water samples, all at low levels. There are no health advisories for source water samples, but Columbia Water is gathering source water samples to develop our body of knowledge on this subject.
For More Information: In order to continue to develop information about PFAS levels going forward, Columbia Water will conduct its own PFAS testing every six months.
Please visit the EPA’s PFAS web page at www.ep.gov/pfas for tools, resources, and EPA actions to address PFAS. SCDHEC also has a resource page at www.scdhec.gov/BOW/perfluoroalkyl-substances-pfas which includes results from all the drinking water systems they sampled.