Update October 1, 2019
Follow-up confirmation samples collected by the Division of Water Quality (DWQ) at Midas Creek upstream of the Jordan River on September 26, 2019, showed E. coli levels above the maximum water quality criteria.
DWQ provides E. coli data when two consecutive samples from a monitoring location exceed health-based criteria.
Utah uses the Most Probable Number (MPN) method to estimate the concentration of E. coli in a water sample. The presence of a high number of indicator organisms such as E. coli signals a higher probability of pathogens in the water. The threshold of 668 MPN of bacterial density per 100 milliliters (mL) exceeds Utah’s water quality threshold for infrequent primary contact recreation. As the value of the MPN increases above 668 MPN, the risk of illness if exposed to contaminated waters also increases.
E. coli concentrations from the September 26, 2019, sample were 980.4 MPN per 100/mL