Shoal Creek rose to well above flood stage Monday afternoon flooding homes, businesses and major downtown streets.
People in Downtown Austin told FOX 7 reporter Jennifer Kendall the water rose very quickly catching most of them off guard.
At the intersection of Parkway and Enfield, there were cars underwater. Neighbors helped save homeowners from the rising river.
Several people say parts of the road the water rose from the ground to chest high in about ten minutes.
At least one person says the water was up past his windows and he had to leave all of his belongings inside.
"We decided it would be smart just to get over here since they said it would rain from 4-7 and by 4:15 the water had risen so much that it was impossible to get through here," said Bruce Shuurman.
Hundreds walked down to North Lamar where the water rose above the doors of several businesses.
Austin firefighters helped employees at the 7-11 wade through the water and some business owners say the items inside their store will have to be tossed out.
Lamar wasn't the only place in Austin that dealt with major flooding, Hyde Park had high water.
The apartment complex, The Retreat, was hit harder than most in the area.
FOX 7 reporter Scarlett Greyson describes it as waist high.
Cars were flooded. Owners could not do anything but watch their vehicles slowly fill up with water.
"Every other car people abandoned their cars they just left them in the middle of the street had their hazards on um people were just running out trying to find higher ground to go. Almost every other car I saw was flooded," said Schuyler Dale.
Many first floor residents left the area.