Transcript for Water rescues carried out around San Jose

Jon, thanks as us. To the emergency playing out tonight. The flash floods that took so many drivers by surprise today. California's 101, and their tires underwater. All of this after the Anderson reservoir in San Jose spilled over. ABC's Neal Karlinsky on the rescues tonight. Reporter: Tonight in San Jose, entire families, even babies-rescued by boat in the middle of their neighborhood. We've been advised that if people are trapped and uninjured to shelter in place. Reporter: The very young and the very old. Dozens of them taken to safety by emergency crews in boats, their only way out of this apartment complex. I have been here for six years, and I have never seen this. It happened real fast. Reporter: At a nearby golf course-more rescues, 20 people believed to be homeless-clinging to trees for safety. Emergency officials say the flooding is the direct result of water being released from Anderson reservoir, what now looks like a man made waterfall. It's one of many reservoirs in the area at or near capacity, leading to low level flooding, including this parking lot full of cars at a nearby college. All of San Jose doubling the Normal amount of rain it normally gets by this point. All of the water in the coyote creek water shed is dangerous. It's swift moving, its carrying debris with it from areas that haven't seen water in years, and on top of that it could be contaminated. Reporter: All this after a powerful 24 hours of rain, smashing northern California leaving trees down and mudslides throughout the area. David, they are still pulling people out of here tonight. The creek flooding this apartment complex hasn't been this high since 1922. This water is filthy. Filled with raw sewage and chemicals. They are hoping this is the worst of it. The weather is finally starting to improve. David? We see the frantic rescue

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