The city of Plano says workers are currently trying to clean up a sanitary sewer overflow that is flowing into White Rock Creek.
The overflow happened in a sewer line maintained by the city at Glen Eagles Golf Course on Tuesday, a Plano spokesman said.
It's estimated that 100,000 gallons of sewer waste-water is involved.
Once the flow is contained, the city says workers will walk the creek to verify any adverse effects to the water or aquatic life.
Plano officials say workers will be monitoring the overflow around the clock and will perform clean-up of the affected area.
The city is advising all residents that the public drinking water has not been impacted and continues to be safe to drink.