Police from Narre Warren were called to single car crash in Parkhill Drive, Berwick about 6pm last night.
On arrival they spoke to a 61-year-old woman from Berwick who was driving a Toyota Echo which had crashed into a sign.
The woman underwent a preliminary breath test and was required to attend a station for an evidentiary test.
She returned an alleged reading of 0.203%.
Her licence was immediately suspended and her car impounded with towing costs of $1005.
She is expected to be summonsed at a later date.