The guerrilla street engineers at the Transformation Department have “staged an intervention” at the intersection of First Avenue and 9th Street, putting down two orange cones to force drivers to take turns more carefully. Earlier this week, a turning truck driver struck and critically injured a woman biking in the First Avenue bike lane at this location.

The block of the First Avenue bike lane approaching 9th Street has a “mixing zone,” in which cyclists and drivers turning left negotiate the same space during the same signal phase.

Intersections that separate cyclists and turning in time with “split-phase” signals have a safer track record than mixing zones, but DOT prefers to limit them to intersections with high pedestrian volumes.

Another option is to compel the turning drivers to take the turn at a sharper angle and slower speed, which is what today’s intervention by the Transformation Department accomplishes. It’s a similar concept to the “protected intersection” design that American cities are starting to test out.

Here’s the intersection before Transformation Department swooped in. Notice how the cyclist has to maneuver around the turning motorists who should be yielding:

And after:

Mixing zone after. Two cones and flowers channel drivers into own lane, forcing a more careful turn across bike lane. pic.twitter.com/xlraMedxg8

— Transformation Dept. (@NYC_DOTr) April 7, 2017