The crash happened around 9:40 p.m. as the mom was driving her minivan on FM 517.
It's unclear why she lost control, but she told first responders she hit a curb on the bridge, veered across several lanes of traffic, and then into the bayou.
Officials say a homeless man who stays in a wooded area near the bayou saw the crash happen and paddled his canoe out to rescue the mom and her baby.
By the time the man was able to get them to shore, Dickinson police were on the scene too.
The Dickinson Volunteer Fire Department also responded to the crash. They used their boat to take the tow truck driver out to the van so it could be hooked up and pulled from the water.
The mom and baby were taken to The University of Texas Medical Branch (UTMB) in League City after the crash. In an update, Det. Lupe Vasquez from Dickinson PD said the mom and her baby are out of the hospital.
Officials say they will be OK and were not seriously hurt.
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