A swim advisory in Butte County has been expanded to include all of Big Chico Creek due to E. coli contamination. Initially, the advisory was limited to Sycamore Pool in Bidwell Park, but Butte County Public Health officials announced the expansion on July 18 after investigating two additional cases of E. coli upstream in the creek. The advisory warns people to avoid entering the water in Big Chico Creek until further notice Testing in Big Chico Creek has not yet begun, according to Health officials it will take several weeks to complete the current round of testing