Coronado Mayor John Duncan challenged the validity of San Diego County’s public health safety testing for ocean water at the Aug. 18 City Council meeting. The tense conversation focused on a relatively new testing protocol implemented in May 2022 to check the sewage levels coming from Tijuana. Before adopting the method, known as Polymerase Chain Reaction (ddPCR), the county relied on Enterolert – a culture-based protocol standardized nationwide by the Environmental Protection Agency (EPA). The EPA approved a pilot program for the ddPCR protocol in 2021 and stated that a study had “found good agreement” between the two methods. However, beach closures in Coronado jumped significantly after the county started using the ddPCR testing.