>> reporter: hey alex. this is the debris from a cabin that was on the banks of the blanco river then swallowed by the river at the height of the flooding. the water climbing 25 feet in just an hour ripping apart homes and families here. from the air, and in the light of day, the streets of houston look more like canals after flash floods swept across the area overnight. more than ten inches of rain in some areas in just hours. cars, trucks even tractor trailers were no match for the rising flood waters that overwhelmed dozens of city streets. response teams carried out more than 500 high water rescues throughout the night and into the day. >> just use good common sense. stay out of the high water. don't drive into the high water. >> reporter: in women berimberlywimberly texas, the search goes on for 12 people after the blanco river crested at more than 40 feet saturday