Multiple lanes reopened at 5 p.m. before the freeway is completely reopened.
The highway was closed after an 18-wheeler swerved to miss a car near I-10 and Post Oak.
Houston firefighters said 10 containers carrying formic acid, an unstable chemical, shifted when the driver slammed on the brakes. The containers slammed into the cab and also damaged the trailer.
The driver was taken to the hospital with minor injuries.
HFD says crews had to siphon the chemicals from the containers into new containers.
Firefighters said they had to take special precautions because the chemical is dangerous to inhale or touch.
No shelter-in-place or evacuation orders were issued as a result of the spill.
Drivers were urged to avoid the area as backups remain.
Alternate routes to I-10 outbound closure: Memorial Drive, San Felipe, Westpark Toll @abc13houston— Katherine Whaley (@KatherineABC13) November 28, 2017
Even J.J. Watt commented on how bad Houston traffic was today.
Houston traffic is on another level today— JJ Watt (@JJWatt) November 28, 2017
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