Police have been told the woman was driving in convoy with a friend along Elmore-Raywood Rd when their vehicles were impacted by water about 7.15pm.
The vehicle the woman, 74, was travelling in was swept off the road into Bendigo Creek at Naughtons Bridge before it travelled about 100m downstream.
The Eaglehawk woman was able to make her way to a tree before a passer-by stepped in and swam out to the woman to help.
It is believed the local man, known as Mitch, swam out to the woman several times before he was able to use a ratchet strap to secure the woman to the tree, according to Victoria Police.
Mitch then stayed with the woman, making sure she was okay, for up to an hour, while emergency services responded and headed to the scene.
State Emergency Service personnel and two Victoria Police Swift Water Rescue Teams attended.
The teams, including members from the Water Police and Search and Rescue Squad, deployed a vessel into the water to rescue the pair.
They were rescued and checked over by Ambulance Victoria paramedics. Neither was injured.
The woman from the other vehicle, even though surrounded by floodwater, was very her lucky car wasn’t swept away. She was assisted by members of the public and made it to dry ground.
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