Transcript for Harrowing stories of survival, recovery after Hurricane Harvey
Reporter: Houstonians are still trying to get their heads above water. This city ravaged by Harvey. As rescues continue for the fifth straight day. By boat -- We're coming right back. Reporter: -- And from the air. Above fort Arthur, Texas Harvey did not let up. In a CBB air marine ops blackhawk -- Witnessing it up close is surreal. They are true heroes. Reporter: -- We first rescued an elderly couple and their dog, stranded in their neighborhood. This woman soaking wet. Patient's inside. Reporter: Hoisted up by basket. We've already made one dramatic rescue. Now we're right back at it. Next the man and his dog. All safe tonight. As if the people of Texas haven't been through enough, now even the shelters are flooding. River inside, outside, upside, down side. Reporter: At the Bob Bauer civic center in Port Arthur, residents were forced to move to the bleachers to avoid the pooling water. And enough is enough. We're now also dealing with catastrophic conditions in southeast Texas. And those conditions are a threat to life and property. Reporter: Harvey now a tropical depression has dropped more than 20 trillion gallons of rain in Texas and Louisiana. At least 31 are now dead. More than 13,000 people rescued so far. Officials going door to door marking bright red Orange Cs on homes that are clear. Authorities estimating up to 40,000 homes in Harris county alone are destroyed. But 100,000 is certainly not out of the question. Reporter: At greens bayou receding water revealing a grim discovery. Inside that van the bodies of six members of the Saldivar family. 84-year-old patriarch Manuel and his wife bellia and their four great grandchildren, the youngest just 6 years old. Family, I just notified them. Obviously, they are devastated as we all are as well. Reporter: They were swept away Sunday as they tried to escape the flood waters. Sammy Saldivar the sole survivor. Yesterday his brother Rick spoke with my colleague Tom llamas. They went together. That's all I can -- you know, that's all I'm happy for, that they went together. That's the only thing you can. Reporter: Almost 100 miles away rescuers are trying to save over 73 elderly residents, many bedridden, stuck in their nursing home for 24 hours. The entire facility enveloped by water. Foti calerges at KTRK, ABC's own station in Houston K took us inside. There are many other patients here in beds and they have to have people lift up their beds and try to carry them out. Do you work here? Yeah, at night. At nighttime. What does it been here? This water just rised all the way -- You know what? I was staying at home watching television and I saw this on TV. I could not believe they were still here. So I waded through the water and somebody gave me a ride on a boat to be here. It just breaks my heart. Reporter: Residents were corralled in the front entranceway. The front driveway turned into a canal. A flotilla of boa lined up as rescuers lifted residents still in tir beds one by one. One, two, three, up. Reporter: Carefully placing them aboard to be reunited with family members. But still -- Reporter: Some of the most critical later evacuated by helicopter. In Crosby, Texas a new danger coming from a flooded manufacturing plant. The CEO of Arkema, inc. Saying in a statement today that given current conditions at the plant chemicals could explode or catch fire. "There is no way to prevent it." Everyone living within a 1 1/2-mile radius has been ordered to evacuate. Back in Houston some brave residents who fled ravaged homes are starting to head back to see what's left. Just days ago the community around spring, Texas submerged. Shazia ashref, a single mom with three kids, never expected the waters to get so high. Today she was determined to face the reality of what remained. We're putting these socks on. The water's receded. So we really want to kind of take a look, go inside and, you know, do a little bit of an inventory, see what's salvageable if anything at all. Reporter: But the journey to get home not easy. This is a street where my kids play. They come off the bus at the end and they walk over here. Thank you. Reporter: And there isn't much to salvage among her belongings. Oh. You can see like water marks all the way up to here. Reporter: But she says she's determined to rebuild. On the other side of town residents already starting over. This is our home. Reporter: This morning student volunteers were helping Danielle Krueger strip down the damaged floors and walls of her home. It's really surreal to see the damage. Reporter: Now a lifetime of memories just a pile of debris on the front yard. Silly girl. Reporter: The last five days have been an emotional roller coaster for many families. The weeks lost their home but gained a life. Yesterday they welcomed a baby girl, Laura Lynn. William Weekes and his mother made the emotional journey home today to port aransas, Texas. His wife unable to travel, recovering in the hospital. This is where my trailer started. That's it over there where the SUV is. Reporter: Their mobile home picked up and tossed by the wind. Toys and clothes scattered on the ground. Look, I found Bela's dress she wore to school. I bet if we wash it -- Reporter: The dress emblazoned with an anchor, symbolic of this Seaside community. So we're saving that for sure. Reporter: For William it's all too much to bear. With the help of a neighbor he chainsaws through what was the roof of their mobile home. Climbing, searching for, and finding precious items. This is the blanket that she was making for the baby. I'm trying to get it out. Yes, sir. We're strong. We're resilient. We are. Thank you so much. That's what it's all about. It is. I'm just so grateful we're all okay. Thank you all for everything. Thank you. Reporter: The strong people of Texas picking up the pieces, putting life together again. For "Nightline" I'm rob Marciano in Conrow, Texas.
This transcript has been automatically generated and may not be 100% accurate.