Residents in three communities in Melbourne's outer east are being warned not to drink their tap water due to storm damage.
Yarra Valley Water has issued the directive for the towns of Kallista, Sherbrooke, and The Patch and anticipates the warning will be in place for at least three days.
People are urged that water should not be used for drinking, washing food, preparing baby formula, or brushing teeth, and people should take special care not to ingest the water when bathing or showering.
Yarra Valley Water says boiling the water will not remove contaminants.