Southern California Costal Water Research Project Authority 1 article published in JoVE Environment A Duplex Digital PCR Assay for Simultaneous Quantification of the Enterococcus spp. and the Human Fecal-associated HF183 Marker in Waters Yiping Cao1, Meredith R. Raith1, John F. Griffith1 1Department of Microbiology, Southern California Costal Water Research Project Authority This manuscript describes a duplex digital PCR assay that can be used to simultaneously quantify Enterococcus spp. and the HF183 genetic markers as indicators of general and human-associated fecal contamination in recreational waters.