Transcript for Good Samaritans risk their lives for Hurricane Harvey rescues
And you're looking at the skyline of the city of Houston right now. The lights are on. That's taken by our drone. And Harvey has inspired an army of heroes to safe their neighbors with everything they have. From jet skis to boats. Many wading through dangerous flood waters to pull victims to safety. ABC's rob Marciano has been on the front line with those responders. Reporter: Long after the flood waters recede, these are the images that will stay with us. To be able to get through the storm the way we did and save so many lives is nothing short of remarkable. Reporter: Strangers risking life and limb saving strangers, by any means available. Rafts, jet skis and canoes. A human chain delivering a pregnant woman to safety. Good samaritans showing up to save the young. Hello. Hi. Hi. Do you want to go on a boat ride, Kate? Can I pick you up and carry you? Reporter: And the old. Oh my god. Reporter: We watched as this woman, soaking wet is hoisted in a basket. A smile, happy to be safe. Surreal. They are true heroes. Earlier this week, hospitals scrambled to evacuate vulnerable patients. Little premie Lilly Villalobos was evacuated along with 10 other critically ill newborns on Thursday from Driscoll childrens hospital in corpus Christi. She was born on March 12th. She was one pound five ounces. She could literally fit in the palm of your hand. Reporter: Parents Leanna and Miguel were unable to go with her. I was scared. It's been a storm for us with our baby being in the NICU since she was born and then having her taken, you know, it was just a nightmare. And all the destruction that the hurricane caused was, it's unbelievable Reporter: But as the waters rose, so did a makeshift citizens armada. Propelled by both their fishing boats and their need to get involved. Everybody's been coming out. Reporter: The scene reminiscent of this summer's blockbuster, "Dunkirk," a flotilla of civilian mariners arriving to save their marooned countrymen. This week Texans answered their own call. We're a little different in the republic of Texas. We look out for each other and we take care of our own. Reporter: Dustin Mcray and Adam rust, fishing buddies from galveston -- What's up, buddy? You all right? Reporter: Have spent the last few days going door to door rescuing more than 300 people. Right now everybody needs help. So we needed to come together and help as many people as we can. Reporter: It's a risky job. The waters teeming with everything from toxic chemicals to colonies of fire ants to gators. Oh, yeah. Reporter: For hours, they scoured this area, saving family after family. Survivors climbing aboard, willing to leave behind their homes, but not their beloved pets. Come here, mosley. Reporter: Both the small kind and the not so small. This hawk sought shelter and found YouTube fame perching in a taxi. He looks scared. He doesn't know what's going on. Reporter: In all the rescues, it's hard to surpass this one. Grandparents in Houston being evacuated right through the front door on jet skis. How did you end up on a jet ski the. We had to evacuate. We had to get out of there. I called Chick-fil-A. That sounds funny, but I ordered a boat. You loaded your possessions onto that boat, and all of a sudden, jet skis showed up. Reporter: I jumped on the back of another one. Sadly, not everyone could be saved, including police sergeant, Steve Perez, who drowned on his way to work just two days shy of his 61st birthday. We couldn't find him, and once our dive team got there, it was too treacherous to go under and look for him. Reporter: And the six members of the Saldivar family, four of them children. On Sunday, their van swept away by flood waters. The road dips and that's where the van started floating and it pulled the van to the right and put it in the bayou. Reporter: Today, a tragic discovery playing out on live television. The sergeant says that a van matching the description is down in the bayou. Initially, we viewed two bodies, appeared to be adults in the front seat of the vehicle, and we can now confirm that four other individuals are in the back of the truck as well, so we have a total confirmed six dead. Reporter: The human toll will likely rise as the waters recede, but so too will the number of joyous reunions like this one. Tonight, that little baby is back. Her parents meeting the plane carrying her home. Oh, man. I mean, I haven't seen her, and just -- I mean, I love my little girl. I just loved her, and just seeing her, it made me so happy. She is back and I'm thankful for everyone that took care of her. Reporter: And just today, the spencers got to thank their heroes in person who whisked them to safety. You're a hero. You're a hero. Reporter: And remember the mother who took to Facebook begging for help? We need help. Reporter: Yesterday, she had a reunion of her own. Hey. Oh, my god. Reporter: A helpful reminder that while so many material possessions can wash away, human life remains precious, fragile and always worth saving. And rob, those first responders did not miss a beat. Reporter: No, they didn't, George, and, you know, worst case scenario, rainfall, but once there was a hurricane in a gulf, they went on high alert here in the state. First responders and the military, and folks who are out of state were told to be on standby, and they got her quickly, and what's more impressive is how well they worked together. In the helicopter, you look out the open door, and you see 10 or 12 more on either side of the aircraft working these tight, urban environments. All sorters of obstacles, have been to scoop up flood victims. Some of which are immotorbike mobile in a tropical storm. It's impressive, and these professionals are precise. The common thread they share with the civilian volunteers is they all have heart. They all want to be here. They all want to help, George. It's impressive all around. Rob Marciano, thanks very much. We'll be right back. That was then, with Katrina. We need help! This is now with Harvey. Please help us. What makes these cities, Houston and New Orleans, so prone to disaster. 12 years later, what lessons can
This transcript has been automatically generated and may not be 100% accurate.