A new guide seeks to answer that question for any street in the world.

The National Association of City Transportation Officials has released a guide to determining what kind of bike infrastructure to install on any given street. It's one of the most comprehensive such guides in the nation, according to Michael Andersen.
By analyzing the basic components of streets—like auto speed, traffic volume, and lane count—NACTO's formula can recommend a type of bike lane for a street with any combination of those factors. For example:
Got a two-lane, two-way 25 mph street that carries 4,000 autos per day? According to NACTO, a buffered bike lane will do. But if the traffic speed is 30 mph, it’s time to protect the bike lane with a curb, posts or planters.
In some cases, the guide also recommends changing the variables that make stricter precautions necessary in the first place—such as by slowing vehicular traffic to reduce the number and speed of cars passing by bike riders. Overall, the calculations are aimed at producing a "high-comfort" experience for riders "of all ages and abilities"—a higher standard than many existing local guides, Andersen points out.
FULL STORY: Which Bike Lanes Should Be Protected? New Guide Offers Specifics

Analysis: Cybertruck Fatality Rate Far Exceeds That of Ford Pinto
The Tesla Cybertruck was recalled seven times last year.

National Parks Layoffs Will Cause Communities to Lose Billions
Thousands of essential park workers were laid off this week, just before the busy spring break season.

Retro-silient?: America’s First “Eco-burb,” The Woodlands Turns 50
A master-planned community north of Houston offers lessons on green infrastructure and resilient design, but falls short of its founder’s lofty affordability and walkability goals.

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Analysis: Cybertruck Fatality Rate Far Exceeds That of Ford Pinto
The Tesla Cybertruck was recalled seven times last year.

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