Morning traffic on the 23 Freeway in Thousand Oaks came to a halt Tuesday after the spill of a gallon of a swimming pool chemical shut down the roadway for two hours and caused traffic tie-ups on surrounding streets for hours.

At 7 a.m. Feb. 1 a caller reported to the California Highway Patrol that a container had spilled and was creating a chemical cloud in the southbound lanes of the 23 Freeway between the Janss Road and Thousand Oaks Boulevard exits, CHP spokesperson Officer Miguel Duarte said.

In response, officers immediately closed the south- and northbound lanes of the freeway.

Capt. Ron Oatman with the Ventura County Fire Department said a HazMat crew identified the chemical as muriatic acid, an ultra-corrosive substance used in swimming pools.

Firefighters neutralized the acid using soda ash, similar to baking soda, and then turned the cleanup over to Caltrans, Oatman said.

The cleanup was completed at about 10 a.m.

Oatman said a full hazardous materials crew of about 30 firefighters was on the scene at one point but was sent back to their stations after it was determined only a dozen or so firefighters were needed to handle the small spill.

“We send what we feel is appropriate,” Oatman said, adding fire officials modified their response after fully assessing the incident.

Northbound lanes of the 23 Freeway were reopened by 8 a.m

The southbound 23 was shut down for a couple hours while traffic was diverted off at the Janss Road exit.

Two lanes were opened at about 9:20 a.m. with all southbound lanes open by by 10:10 a.m., Duarte said.

North- and southbound transition roads from the 101 Freeway onto the northbound 23 Freeway were also closed. . Chris Rowell, a Newbury Park resident, was caught in the thick of it all at 8:30 a.m. while on his way to drop off his 4- year-old son at a preschool in Thousand Oaks and before going to work in Westlake Village.

He said surface streets surrounding the freeway interchange were backed up so badly that he pulled over and resumed his commute after an hour.

Traffic was still backed up on main streets after 9:30 a.m., but Rowell, familiar with the area, took residential streets and arrived at work 15 minutes later.

The trip, which normally takes 20 minutes from home to work, took more than 90 minutes, Rowell said.

“It just makes you wonder— it wasn’t that big of an incident and it clogged up everything,” he said.

Duarte said it’s fortunate no one was injured and that the CHP is investigating who may have spilled the dangerous substance.

“We’re hoping that somebody will come forward,” he said.

Anyone with information about who may have dropped the container is asked to call Officer George Myers at the Moorpark CHP station, (805) 583-0800.