You may have noticed if you drive on 35th SW that the speed limit has changed on that busy road. It has gone down, substantially. It is now 25 mph. 

Speed is the critical factor in the frequency and severity of crashes. A few miles per hour difference can make a big impact.

SDOT says:

What are the default speed limits in Seattle?

In 2016, we lowered citywide default speed limits, in support of our Vision Zero efforts to make streets safer for everyone. Here's what changed:

• All non-arterial streets (what we think of as residential streets, where there is no dividing yellow line) went from 25 MPH to 20 MPH
• All arterial streets (more major streets, with a dividing yellow line) went from 30 MPH to 25 MPH, unless otherwise posted (the latter took effect primarily downtown and in nearby neighborhoods)

Lowering speed limits has been and will continue to be a key part of Seattle’s Vision Zero efforts to end traffic deaths and serious injuries on city streets by 2030.

Lowering speed limits in urban villages

In 2017, we began evaluating and setting new speed limits for arterial streets within urban villages (think: neighborhood business districts). These are where we see the most activity (lots of people walking, biking, driving, and taking transit) and the most crashes involving pedestrians. We're continuing this work in 2018 and beyond. In addition to replacing existing sinage, people can expect to see more speed limit signage, to help increase awareness.

If you have questions about speed limits in Seattle you can check out SDOT's Speed Limit map here.