UPDATED 2:35 p.m. After some city of Austin residents reported early Feb. 7 foul-smelling water was coming out of their taps, Austin Water released a statement saying the city’s water supply is meeting “all regulatory standards and is safe to drink.” To address the issue, Austin Water is adding powdered activated carbon, which is used to help with taste and odor issues, according to the statement. It is also flushing water lines in the affected areas of Central and South Austin. By the afternoon, Austin Water reported it believes zebra mussels in a raw water pipe at Ullrich Water Treatment Plant, located at 1000 Forest View Drive, Austin, are the source of the odor issue. Austin Water had put the pipe back into service Feb. 6 after finishing repairs over the past two weeks, according to the department. This incident arrives a few months after the city of Austin experienced an unprecedented weeklong boil notice following heavy rainfall that overwhelmed Austin Water’s treatment plants with silt-laden water. Editor's note: This post was updated with new information.