What are the orange cables sprouting off Highway 99 in South Sacramento? Bee Curious answers

Along the dirt paths on Highway 99 by south Sacramento, bright orange stems are sprouting from the ground — and they aren’t plants.

Two readers reached out to Bee Curious, a community-driven series where reporters answer questions about Sacramento, to figure out what they are.

Selina Barron said she’d seen these orange cables coming from a ditch, driving past Florin Road going north on Highway 99.

“If you drive Hwy99 West,” Ruthann Biel said in an email to The Bee, “anywhere from Elk Grove to the 50/80 interchange past 12th Avenue, you will see the orange tubes by the side of the freeway, often with signs that say ‘Open Trench.’”

Readers asked Bee Curious about these orange cables sprouting on the side of Highway 99 near South Sacramento.
Readers asked Bee Curious about these orange cables sprouting on the side of Highway 99 near South Sacramento.

The Bee reached out to the California Department of Transportation to find the answer.

What are these cables?

Sergio Ochoa Sánchez, spokesman for Caltrans District 3, said that the orange cables are called SDR9 Fiber Optic Conduits and are used for fiber optics.

Fiber optics, according to Verizon, are a type of technology used by internet, phone and TV services to transfer information in the form of light. Strands of fiber are encased in plastic and they can send data signals hundreds of miles, faster than traditional electric cables.

Sánchez said that the orange wires that peak from the trenches are called “conduit stub up,” “pull point” or “splice point.”

“A pull box or pull vault will be placed over these conduits. Pull box lid will be marked as “Caltrans Fiber Optic” accordingly,” he said.

What are the fiber optics used for?

He said the fiber optics seen on Highway 99 will be used for the Intelligent Transportation System.

The system, according to the CalTrans website, helps improve safety, mobility and productivity by fusing communication technology with transportation infrastructure and cars.

”The Intelligent Transportation System (ITS) are sensors underneath the highway surface, and the cameras are part of that system,” Sánchez said. “Sensors underneath the surface, let Caltrans dispatch throughout the state in each district, know what the traffic flow is by how fast the vehicles move over each sensor.”

He said this is how maps can show “red” for stopped traffic, “yellow” for slow and “blue” when there’s free-flowing traffic.

“The newer cables, fiber optic, will speed up that process,” he said.

There is an ongoing Fiber Optic Project running through Sacramento County on Highway 99 from Grant Line Road to Highway 50 and on Highway 51 from Highway 50 to 0.1 mile south of the Fort Sutter Viaduct.

The more than $16 million project started in February and is expected to be completed this November, according to project details.

There was a similar project last year on these freeways to improve and upgrade communication speeds.

What do you want to know about life in Sacramento? Ask our service journalism team your top-of-mind questions in the module below or email servicejournalists@sacbee.com.