The German claimed her first Grand Slam title on Rod Laver in Saturday evening's final, and around 12 hours later she and her coaches went for a dip just outside Melbourne Park.
Kerber had made a bet with Eurosport journalist Matthias Stach that she would emulate Boris Becker following his 1991 title win, and Jim Courier the next two years, by diving into the river should she lift the trophy.
She was careful though to keep her head above water, with Courier having contracted a stomach bug upon his second visit to the polluted waters.
"It was cold and a little dirty. I was just trying to enjoy it, because that was the bet," she told reporters, before wrapping herself in a dressing gown straight afterwards.
After pulling off one of the greatest Grand Slam final upsets in recent memory against 21-time major singles champion Williams, Kerber -- who saved a match point in the first round against Misaki Doi -- is now targeting the American's world No.1 ranking.
Kerber has risen from No.92 in 2011, the same year she lost to Sam Stosur in the US Open semifinals, to No.2 in Monday's revised WTA rankings.
"The message from me is that you can work very hard and some day the work will pay off," Kerber told reporters at Melbourne's Government House.
"Just follow your dreams and be patient. You will always have ups and downs in your life and your career but just stay positive and go for it. Just do what you love.
"My dream was always to win a Grand Slam and my second dream was to be No.1. My first dream I have done already and the next one will be No.1.
"Serena is still the best player in the world. She wins most every tournament she is playing in.
"This is so far away for me. I will try not to think about it but, if the day came -- some day -- when I am No.1, then great."
Kerber also revealed she had been inspired by her compatriot Steffi Graf when she paid a visit to Las Vegas for a training block with the former world No.1, describing it as "a special moment".
"Growing up in Germany, we had Steffi there, we had Boris [Becker] there," Kerber added. "They won Wimbledon when they were 17 or 18 and they won everything. So it was not so easy to make tennis so big again.
"Right now the Germans are on the right path to make tennis more popular again -- with the Grand Slam title from me and we have so many good players. We played the Fed Cup final a few years ago. I think it's going in the right direction.
"I got so many messages from home. I know I will make a lot of media and press when I get back. But I think I deserve it. Right now I will just be focusing on the moment and enjoying everything. Then let's see what will happen, I have no idea. I was never in this situation."