The rate of carpooling to work has been steadily declining in recent decades, but a crop of apps in the model of Uber is paving the way for a new wave of ridesharing.

Carpool commuting made up 20 percent of all work trips in the 1980s, when the Census began measuring it. That rate has declined every decade since. The most recent surveys say just 9.4 percent of commuters carpool nationally, though in Los Angeles it's a bit higher, at 10.7 percent.

"Carpooling is a significant and important mode and to see it decline so much sends up some warning signs," says Steven Polzin, director of Mobility Policy Research at the University of South Florida's Center for Urban Transportation Research.

Polzin says the shift is too big to be accounted for by slight upticks in other modes, such as transit or biking. Rather, more commuters than ever are driving alone, which Polzin says creates a lot of empty seats on the road. He says filling them is the simplest solution for reducing congestion. Unlike transit construction, it doesn't cost billions of dollars, and it's actually more convenient for many commuters.

Jennifer Caballero can certainly attest to that. She lives in Pasadena and works 25 miles away at the Skirball Center. When she started the job, she took two buses to get to work, which frequently took more than two hours.

Now she carpools, which usually takes less than half the time and has social benefits.

"Having somebody else in the car just makes the time go a little bit faster," she says.

For seven years, Caballero has driven to work with her coworker Marilyn Delanoeye, who lives nearby in Altadena. But creating an enduring carpool has not been without challenges.

"I have a little part of my brain that is just devoted to organizing the carpool," says Caballero, who admits that she has on one occasion stranded her partner at work with no way to get home.

"That was a low point."

But Caballero says the two of them have stayed committed by keeping up strong communication and a flexible attitude.

Not only do Jennifer Caballero and Marilyn Delanoeye carpool, they also drive electric.

Polzin says not everyone can do that these days. With all of the many demands on our schedules, people are more likely to engage in what he calls "trip-chaining."

"They’ll stop and pick up dinner, they’ll drop off kids, they’ll drop off laundry," he says. "So they don’t want to sacrifice that personal flexibility to coordinate with someone else."

Working conditions are also less conducive to carpooling than they used to be. The decline in manufacturing and dispersion of many large companies into smaller, more spread out employment centers makes it harder for co-workers to stay on the same route and schedule. More employees telecommute or shift their hours.

Despite the breakdown in traditional carpooling, new technology is giving people hope that ridesharing can be reinvented.

"I definitely think that this whole sharing economy is a good thing," says Gouthaman Balaraman, a quantitative analyst who has been looking for a steady carpooling partner to join his 35-mile commute from Cerritos to Santa Monica.

"People are warming up to the idea of getting into the car with a stranger," he says.

While he doesn't think for-profit services like Uber Pool or Lyft Line are an economical solution for his daily commute, he does think their model of matching random drivers with one or more passengers could work for commuters who haven't had luck finding a partner within their own company.

After trying out some carpool-matching websites with little success, Balaraman decided to try making his own, calling it UCarpool. He learned from Reddit forum comments what turned people off of carpooling and designed a site he hopes will correct for many of the pitfalls he's observed so far, such as sites that share too much of your private information to casual searchers.

There are also several new apps that offer potential ridesharers ways to connect without paying the higher cost of Uber or Lyft: Ride and Carzac are slowly building users and the popular mapping app Waze is testing a carpooling service in Tel Aviv.

"The new paradigm is a much more dynamic arrangement," Polzin says. "You may get picked up by any number of different people. It may not be the same people from one day to the next."