What L.A.'s New Expo Line Extension Won't Do

The $1.5 billion, 6.6-mile light rail extension from Culver City to Santa Monica is projected to double trips on the line by 2030, giving commuters a viable alternative to driving. Just the same, don't expect the extension to reduce congestion.

3 minute read

May 23, 2016, 10:00 AM PDT

By Irvin Dawid


Expo Line

Neon Tommy / Flickr

Metro Expo Line Map (Image)

Credit: LA Metro Expo Line (note seven new stations: Palms—Santa Monica)

"The light rail extension won’t put a dent in traffic, not in the long run," writes Aarian Marshall for Wired. "But it’s still worth every penny.

So much for Los Angeles Mayor Eric Garcetti's assurances last February. 

The Expo Line connects and crosses through some of our most traffic-ridden corridors,” Garcetti said. “This is a huge step forward in our work to ease congestion.”

Induced demand applies to transit as well as asphalt

Growing the ridership by 35,000 trips to 64,000 in 14 years will be a major feat, but how will the extension impact congestion? Marshall asks transportation expert, Professor Genevieve Giuliano of the University of Southern California (USC) what the effect would be if ten thousand motorists chose to immediately forsake driving and take the Expo Line. Giuliano has been studying the issue.

“Ten thousand vehicles out of literally hundreds of thousands that are moving around—it would be really hard to see,” she says.

In a study published last year, Giuliano and her colleagues used sensor data to take a close look at how the opening of the first phase of the Expo line in 2012 affected congestion in the immediate area. They didn’t see much. “The congestion reduction benefits of [light rail] are likely very limited,” they concluded.

You can thank the rule of induced demand: More space for cars doesn’t mean less traffic, it means more cars. When folks ditch their cars for a smooth and stress-free transit ride, other drivers move to exploit a suddenly less clogged stretch of freeway, either by changing their driving patterns or taking trips they wouldn’t have otherwise. The new Expo Line will move more people more places, sure. But it won’t cure traffic.

Looking at Planetizen posts tagged under the topic, it's easy to see that the concept is generally applied to adding more vehicle capacity, which has the adverse impact of reducing transit ridership, unlike adding transit capacity.

“The best thing you can say is that [the Expo extension] will provide people with an option for traveling in congestion,” says Brian Taylor, director of UCLA’s Institute of Transportation Studies.

Taylor is wary of exorbitant rail projects that are attractive to voters but may "betray 'transit’s critical social service function'": improving the lives of lower income people, particularly when lower-priced, high-frequency bus service may prove more cost effective.

A few streetcar projects that may fall in the category were posted here recently. 

A final note on the transit—traffic congestion relationship taught to me by public transit advocate Roy Nakadegawa. While transit may not place much of a dent in traffic congestion, congestion prompts the need to create and improve public transit, as well as adding road capacity. Perhaps the best way to tackle congestion is through economic means.

See more Planetizen coverage of the Expo Line which opened Friday after six years of construction.

Hat tip to Metro Library's L.A. Transportation Headlines

Friday, May 20, 2016 in Wired

Green rapid transit bus pulled into station in dedicated lane.

Indiana Once Again Considering Ban on Dedicated Transit Lanes

The proposed legislation would impact the construction of planned IndyGo Blue Line, the third phase of the city’s bus rapid transit system.

February 25, 2024 - Fox 59

Aerial view of New York City architecture with augmented reality visualization, blue digital holograms over buildings and skyscrapers

4 Ways to Use AI in Urban Planning and City Design

With the ability to predict trends, engage citizens, enhance resource allocation, and guide decision-making, artificial intelligence has the potential to serve as planners’ very own multi-tool.

February 20, 2024 - ArchDaily

View from shore of Sepulveda Basin water catchment basin with marsh plants along shore.

LA’s ‘Spongy’ Infrastructure Captured Almost 9 Billion Gallons of Water

The city is turning away from stormwater management practices that shuttle water to the ocean, building infrastructure that collects and directs it underground instead.

February 25, 2024 - Wired

White Honolulu Skyline train on elevated track.

Hawai’i Transportation Projects Receive Federal Grants

State officials say they need around $15 billion to mitigate the impacts of rising seas.

5 hours ago - Honolulu Civil Beat

Close-up of office building with windows and sign for Department of Housing and Urban Development in Washington, D.C.

Feds Announce Over $3 Billion in Homelessness Assistance Funding

The Continuum of Care grants are directed to programs that provide supportive services and boost housing stability.

6 hours ago - Building Design & Construction

Power plant infrastructure against a sky at dusk with a virtual white globe overlaid on top.

AI’s Growing Threat to Climate Justice

Emerging technologies like AI have great promise for climate innovation, but also a hidden environmental footprint could lead to disproportionate harm to low-income and marginalized communities.

7 hours ago - Brookings Institution

Urban Design for Planners 1: Software Tools

This six-course series explores essential urban design concepts using open source software and equips planners with the tools they need to participate fully in the urban design process.

Planning for Universal Design

Learn the tools for implementing Universal Design in planning regulations.