A recent study by the New York City Department of Transportation on buffered bike lane interventions showed maintained traffic speeds while cyclist safety increased.

One of the biggest barriers to implementing bike lanes in certain municipalities is their perception of slowing down car traffic. However, according to a recent study by the New York City Department of Transportation reported on by Eric Jaffe at CityLab, these urban interventions actually did not reduce car speeds, but maintained them while increasing cyclist safety.
One of the interventions studied was the 2008 and 2009 Eighth Avenue bike lanes, between 23rd and 34th streets. According to Jaffe, before the treatment, "the avenue carried four travel lanes, one parking lane, one parking-rush hybrid, and an unprotected bike lane. Again, by narrowing the lanes, all five were preserved (though the hybrid became a parking lane) even as riders gained additional protection."
With the protected bike lanes in place with a buffer, DOT measured a 14 percent overall reduction in daytime travel times along the corridor. Similar results were found along many other corridors where protected bike lanes were created.
A DOT spokesperson shared with CityLab that another street redesign was adding left-turn pockets, contributing to the maintained traffic speeds. According to the spokesperson, originally, "cars turned left from a general traffic lane; in the new one, they merged into a left-turn slot beside the protected bike lane. This design has two key advantages: first, traffic doesn't have to slow down until the left turn is complete, and second, drivers have an easier time seeing bike riders coming up beside them."
FULL STORY: When Adding Bike Lanes Actually Reduces Traffic Delays

What ‘The Brutalist’ Teaches Us About Modern Cities
How architecture and urban landscapes reflect the trauma and dysfunction of the post-war experience.

‘Complete Streets’ Webpage Deleted in Federal Purge
Basic resources and information on building bike lanes and sidewalks, formerly housed on the government’s Complete Streets website, are now gone.

Downtown Los Angeles on the Rise: A Promising 2025
Fueled by new developments, cultural investments, and a growing dining scene, downtown Los Angeles is poised for significant growth in 2025, despite challenges from recent wildfires and economic uncertainties.

San Francisco Slow Streets Bucks Citywide Trend, Reducing Injuries by 61 Percent
Low-cost interventions aimed at slowing traffic are making a major impact on road safety.

How Single-Family Conversions Benefit Both Homeowners and Cities
Converting single-family homes to triplexes can ease the housing crisis and offer affordable, flexible options for more households. Why is it largely illegal?

Report: Transportation Equity Requires More Than Electrification
Lower-income households often lack the resources to buy electric cars, signaling a need for a more holistic approach to improving mobility and lowering transportation costs.
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.
Economic & Planning Systems, Inc.
UCLA Lewis Center for Regional Policy Studies
Mpact (formerly Rail~Volution)
Chaddick Institute at DePaul University
City of Piedmont, CA
Great Falls Development Authority, Inc.
HUDs Office of Policy Development and Research