Why we Can't Build Our Way Out of Congestion - and What Actually Works?!
Today we thought we would touch on the age-old topic of trying to build our way out of congestion.
Old school traffic engineering views still hold strong to this day - eg a view that more lanes equal less traffic or less congestion. However, this has been shown to fail in countless cities around the world.
The reason is pretty well understood now...Induced demand.
In simply terms, bigger roads attract more drivers until you’re back where you started (or worse).
Real World Examples:
There are plenty of real world examples that illustrate this point:
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Los Angeles I-405 “Big Dig” Widening (2014–2017) Spent US$1.3 billion to add lanes—and traffic volumes jumped by 10% in six months. Congestion eased briefly, then levels increased right back as new drivers flooded in.
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Houston Katy Freeway Expansion (2008) Expanded to 26 lanes at a cost of US$2.8 billion. By 2012, travel times during peak had actually increased by 20%.
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Beijing’s Ring Roads Four new beltways built between 2000 and 2010 couldn’t keep pace with skyrocketing car ownership. By 2015, average speeds dipped below 15 km/h in rush hour.
Why More Asphalt Fails
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Drivers adjust: they take longer trips, shift back to peak times, or ditch transit for “new” capacity.
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Land-use patterns expand: developments sprout along widened corridors, spawning fresh traffic.
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Maintenance eats budgets: more pavement means more potholes, fewer resources for transit or bike paths.
Alternatives That Make a Difference
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Congestion Pricing: London’s Ultra Low Emission Zone cut central-area traffic by 15% in its first year—and funded new bus routes.
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Rapid Transit Investments: Bogotá’s TransMilenio Bus Rapid Transit moved 2 million passengers daily, slashing car trips along its corridor by 30%.
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Active Mobility Networks: Copenhagen’s cycling superhighways carry nearly half of peak-hour commuters—at a fraction of the cost of a single motorway lane.
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Demand Management: Flexible work hours, telecommuting incentives, and dynamic parking fees shift travel out of the squeeze.
Building roads feels intuitive, but it’s a short-lived fix. Real relief comes from smarter pricing, better transit, and urban design that lets us live, work, and play without relying on cars.
How are you rethinking congestion in your city—what’s one non-road solution you’ve seen (or dream of) that truly changed the commute?
Till next time,
Andrew
Transit Trends · Andrew Collings, KA Advisory. Read and comment on the original on LinkedIn.
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