As the contractions began a couple of hours later, Greg tried to call 911, the US emergency helpline number, but couldn't get through.
Greg's mother, Sue Chor, who had arrived earlier to help the couple, was finally able to get through to the National Guard, only to learn that the troops would not arrive quickly enough.
The Smiths - both doctors themselves - were trapped, and their baby was fast on its way.
The couple began to prepare for a home birth, though Greg, not trained in obstetrics, was very worried.
As it happened, however, their apartment complex was home to many medical professionals.
"Mid-morning my downstairs neighbor went into labor. The couple couldn't reach 911, so a complex wide email was sent out asking for nurses and OB's... Suddenly our building was filled with others from our complex showing up to help!" writes Molly Akers, a neighbour, on Facebook.
Meanwhile, somebody phoned a person whose father lived across the street from a fire department, who managed to wade through the water and inform the fire department about the trapped family.
"I just kind of held on to them one person at a time and crawled along their arms until the firemen helped me up the ladder onto the truck," said Andrea to ABC News.
Watch the heartwarming video below:
Their baby daughter, Adrielle Smith was born on Sunday morning.
Love and light to Andrea and Greg Smith who welcomed a baby daughter, Adrielle, after a human chain rescued them from their home in Houston. pic.twitter.com/8uglpy3iwz- Michael Skolnik (@MichaelSkolnik) August 31, 2017
"We had two miscarriages before this," said Greg to People.com. "Everything about this pregnancy we said is God's will. That's why her name is Adrielle. It means she belongs to God." Click for more trending news
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