Tag Archive for 'roadway striping'

Road Diet Data: Studies show projects lead to safer roadways

The Seattle Department of Transportation has been performing road diets or road rechannelizations for decades and argues that these projects bring about safer streets without affecting traffic volumes. SDOT collects data on traffic volume, vehicle speeds, and collisions both before and after each project. In a joint effort with Seattle Neighborhood Greenways, I’ve reviewed the studies and found SDOT’s claims to be true as you can see in the key data presented below.

Looking at the numbers, there is some change in roadway volume after the projects, but no consistent pattern that would suggest roadway capacity is being unduly limited. On the positive side, there are significant reductions in aggressive speeding (drivers going 10 miles per hour above the speed limit), including a 93% decrease from the Nickerson St road rechannelization. All collisions are down as a result of these projects and injury collisions have been decreased even further, ranging from a 17% to a 75% decrease.

In short, road diets are a powerful tool the city has to work towards the newly-announced Vision Zero plan.


Greenwood Ave improvements

Visit SDOT’s blog to see photos of the new road striping on Greenwood Ave.

This project, which is consistent with the Greenwood Neighborhood Plan, enhances access to businesses, improves pedestrian safety, maintains transit efficiency, and provides bicycle facilities while reducing vehicle speeds and maintaining vehicle carrying capacity.

Crews changed the number of travel lanes to one lane in each direction, extended turn pockets at the intersection of Greenwood and N 85th St, installed a new center turn lane, and added bicycle lanes in both directions.


S Columbian Way improvements

SDOT has made several improvements along South Columbian Way. In addition to re-striping the roadway and installing curbs, the sidewalks have been raised and re-paved. These improvements create a safer and more pleasant pedestrian environment.