Around 192,000 gallons of sewer poured into the Cedar Bayou stream from the sewer line on Bayou Avenue.
The overflow was discovered around 5:30pm Friday and it took about 24 hours for crews to contain it.
Baytown's Public Works Department said the city is cleaning up and disinfecting affected areas.
The city says the cause is under investigation, but officials believe heavy rains caused the problem.
