Induced Demand

Aerial of I-10 freeway interchange in Houston, Texas.

Induced demand is real: Commutes on Houston's 26-lane freeway take 51% longer after expansion

A massive freeway expansion only led to longer drive times, showing that building more lanes won't solve congestion.

August 3, 2026 - Space Daily

Busy bike lane in London, England.

Study: Induced Demand Works for Bikes and Transit, too

If you build it — bike infrastructure, bus lanes, and sidewalks, that is — they will come.

January 11, 2026 - Streetsblog USA

Traffic on a freeway heading into downtown Los Angeles on a sunny day.

Report: Caltrans Models, Which Guide Billions in Transportation Funding, are Inaccurate and Outdated

Many of the predictive models used by California’s transportation agency fail to account for post-pandemic travel patterns and induced demand.

November 16, 2025 - State Smart Transportation Initiative

Aerial view of Brampton, Ontario, Canada.

This Toronto Suburb Has More Bus Riders Than Columbus, Ohio

Brampton, Ontario used gradual improvements in service to prove that if you build it, they will ride.

April 15, 2025 - Bloomberg CityLab

Green and white interstate freeway signs pointing to Hayward and San Mateo and Half Moon Bay exits in Northern California.

San Mateo Formally Opposes Freeway Project

The city council will send a letter to Caltrans urging the agency to reconsider a plan to expand the 101 through the city of San Mateo.

April 9, 2025 - Streetsblog San Francisco

Close-up of rear car bumper in traffic on freeway.

Research Shows More Roads = More Driving

A national study shows, once again, that increasing road supply induces additional vehicle travel, particularly over the long run.

March 23, 2025 - Road Capacity as a Fundamental Determinant of Vehicle Travel

Heavy traffic on freeway in San Diego, California.

Why Traffic Never Gets Better

Despite abundant research showing that roadway expansions provide limited congestion relief and increase long-term traffic problems, they still occur due to wishful thinking: advocates claim that “this” project is different.

December 12, 2024 - Greater Greater Washington

Columbia Bridge on Interstate 5 between Washington and Oregon.

Opinion: I-5 Expansion EIR Deludes Itself

The environmental impact report for a massive highway project in the Pacific Northwest ignores the reality of induced demand.

October 24, 2024 - The Urbanist

Aerial view of road construction with yellow heavy equipment parked next to two-lane asphalt road against green forest and blue sky

Study: Cost of Expanding Roads Outweighs Benefits

New research shows that the economic benefits of roadbuilding projects don’t come close to exceeding most projects’ costs.

September 8, 2024 - Bloomberg CityLab

Google street view of Amboy Road in Staten Island, New York.

Staten Island Road Widening Project Moves Forward

New York’s Department of Transportation plans to double the width of a Staten Island street to accommodate more vehicular traffic.

August 13, 2024 - StreetsBlog NYC

Close-up of traffic congestion from behind cars on a freeway in the San Francisco Bay Area.

States Claim Highway Expansions Reduce Emissions

The argument is being used to channel climate funding to projects that expand automobile infrastructure, according to an analysis from Transportation for America.

August 12, 2024 - Bloomberg CityLab

Vintage filtered photo of Interstate 405 North and South sign

Toll Lane Rebellion Fails to Materialize in Southern California

The 405 Express Lanes will open in Orange County later this year despite the warnings from a former Huntington Beach mayor of a resident-led rebellion in response to road pricing. But will the toll lanes mitigate congestion? Academics weigh in.

July 25, 2023 - Los Angeles Times

Blue and white Interstate 15 North sign against backdrop of blue sky and snow-capped mountains in Utah

Utah DOT Plans to Expand Interstate Despite Local Concerns

With more evidence pointing to the futility of expanding freeways, the state could take a creative approach to improving travel times and providing additional transportation options.

May 31, 2023 - The Salt Lake Tribune

A map of the area of Virginia near Occoquan, Virginia shows. stretch of Interstate 95 that will be widened.

I-95 Widening Breaks Ground in Virginia

A mile-and-a-half-long section of Interstate 95, which handles 80,000 vehicle trips a day, will be expanded in Virginia. The project includes a new shoulder, lighting, and noise walls.

May 1, 2023 - WTOP

Blurred night view of gridlocked traffic on freeway

Congestion Growing in Sunbelt Cities

Cities with rapidly growing populations and inadequate public transit systems are seeing more gridlock despite changes in commuting patterns and the rise of remote work.

March 15, 2023 - The Wall Street Journal

Yellow on black "Expect Delays" traffic sign

A Serious Critique of Congestion Costs and Induced Vehicle Travel Impacts

Some highway advocates continue to claim that roadway expansions are justified to reduce traffic congestion. That's not what the research shows. It's time to stop obsessing over congestion and instead strive for efficient accessibility.

March 14, 2023 - Todd Litman

Rural Traffic

Should We Continue to Ignore Induced Vehicle Travel Costs?

A recent Planetizen blog claims that urban highway expansions reduce traffic congestion and benefit everyone. That must be a joke! Most planners now recognize that such projects tend to be economically wasteful and contradict community goals.

February 26, 2023 - Todd Litman

View of blurry speeding cars on freeway at sunset

Opinion: Induced Travel Demand Induces Media Attention

Induced demand is a popular concept among urbanists, but does its pervasiveness obscure the true costs of mobility?

February 22, 2023 - Steven Polzin

Rendering of freeway deck over Interstate 10 in El Paso

El Paso Freeway Cap Linked to Road Expansion

A deck reconnecting neighborhoods divided by the interstate is part of a controversial freeway expansion proposal.

January 27, 2023 - Smart Cities Dive

An image taken from the point of view of a driver on a mostly empty freeway, with large overpasses overhead.

Induced Demand Be Damned: Missouri Governor Proposes I-70 Expansion

Highway widenings still attract support from both sides of the political aisle, despite the inadequacies of the approach in solving the problems it intends to solve.

January 23, 2023 - The Kansas City Star

FREE Course: Walkable City 1: Why Walkability?

After describing his path towards focusing on walkability as the essence of good planning, Jeff Speck marches through his five principal reasons for making more walkable places.

Reinventing Malls: Planning Alchemy—Turning Gray Fields Into Gold

The course focuses on the opportunities and imperatives that shape reinvention of mall sites.

Professor of Urban Planning

Harvard University Graduate School of Design

Transportation Planner I

KFH Group Inc.

Director, Strategy and Research

Greater Baltimore Committee

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