Left Turn Traffic Calming

Left Turn Traffic Calming is a citywide program focused on reducing left turn speeds and enforcing safe turning behavior. The program is part of the overall Vision Zero initiative to eliminate traffic fatalities, severe injuries and reduce the number of traffic injuries.

Jewel Ave & 110 St
Jewel Ave & 110 St

DOT initiated the program as part of the Left Turn Study Action Plan to address failure to yield crashes caused by left turning vehicles. Read more about the Left turn Study. The office of Research, Implementation & Safety manages the program and installed treatments on 107 citywide intersections in 2016 as well as 110 intersections in 2017.

Left Turn Traffic Calming Treatments

DOT selects feasible locations after checking against several criteria involving crash injury numbers, lane configuration and effect on large vehicles’ turning movements. View a list of Left turn Traffic Calming installations across New York City’s five boroughs
Also view an interactive map of all 2016 & 2017 citywide Left Turn Traffic Calming installations along with other relevant safety information.

Left Turn Traffic Calming Treatments

Left Turn Traffic Calming treatments are installed in a variety of intersection configurations, but in all cases these treatments are designed to address problematic left turns

Basic Hardened Centerline

Proposed Basic Hard Centerline
Installed where a one-way or two-way meets a two-way

The Basic Hardened Centerline treatment constists of 6 pieces of rubber curb and bollards installed on the centerline starting from the crosswalk. Starting in 2016, this treatment was installed at 129 locations to date including Amsterdam Ave & 96 St in Manhattan.

Complete Hardened Centerline

Proposed Complete Hard Centerline
Installed where a one-way meets a two-way

The Complete Hardened Centerline treatment includes 6 pieces of rubber curb and bollards, “No Parking” markings and slow turn wedge/box markings coupled with flexible plastic posts. Starting in 2016, this treatment was installed at 37 locations to date including Park Pl and Vanderbilt Ave in Brooklyn.

Slow Turn Wedge

Proposed Slow Turn Wedge Delineators
Installed where a one-way meets a one-way

The Slow Turn Wedge treatment consists of “No Parking” markings as well as slow turn wedge/box markings coupled with flexible plastic posts. Starting in 2016, this treatment type was installed in 38 citywide locations to date including 89 Ave & 164 St in Queens.

Bike Island Channelization

Bike Island Channelization
Installed where a one-way meets a one-way

The Bike Island Channelization Treatment is only installed adjacent to existing bike islands. It consists of Bike Island Channelization box with flexible plastic posts.This treatment was installed at 16 citywide locations starting in 2017 including 2 Ave & 25 St in Manhattan.

Amsterdam Ave & 96 St, MN
Amsterdam Ave & 96 St, MN
Park Pl & Vanderbilt Ave, BK
Park Pl & Vanderbilt Ave, BK
89 Ave & 164 St, QN
89 Ave & 164 St, QN
2 Ave & 25 St, MN
2 Ave & 25 St, MN

Safety Results

In New York City intersections where Left Turn Traffic Calming Treatments have been implemented, median left turn speeds have decreased by 19.9%. Average left turn speeds have decreased by 20.5%. 85th percentile left turn speeds have decreased by 16.7% and maximum left turn speeds have decreased by 11.7%. Vehicles are making safer turns as well; the rate of crossing the double yellow line while turning has dropped by 78.9% for locations that have a treatment extending to the stopbar and 100% for locations that have a treatment extending all the way to the crosswalk. DOT expects to see a reduction in traffic injuries once enough before/after crash data becomes available.

2018 Program Planning

DOT is currently planning Phase 3 of this program where additional intersections will be selected for treatment installation across the city.