Go sLOw: 20 is Plenty

20 MPH Residential Speed Limits

On September 2, 2025, the Lake Oswego City Council approved an ordinance to lower the speed limit on local residential streets and some neighborhood collectors in Lake Oswego from 25 miles per hour (mph) to 20 mph.

This promotes safer conditions for people walking, biking, using mobility devices, riding the bus, and driving.

Residential streets make up around 80 percent of Lake Oswego’s street network. This program includes about 150 miles of streets. See which streets are included using this map.

Slower Speed, Safer Streets

Reducing speeds through the 20 is Plenty program is a 2025 City Council goal. Lower speed limits on residential streets can lead to safer travel conditions for everyone using the street, as well as encouraging a more comfortable environment for people walking, rolling, and riding.

A speed reduction from 25 mph to 20 mph can have life changing results for pedestrians. Crash data has shown that risk of injury and death during a collision decreases significantly between 25 mph and 20 mph. At 20 mph, drivers have more time to react, and crashes are less likely to be fatal. This is particularly true for vulnerable roadway users, such as people walking and biking. 

Source: https://www.ite.org/technical-resources/topics/speed-management-for-safety/speed-as-a-safety-problem/

Implementation Timeline

The program was a two-phased approach. The rollout plan included starting in the northwest corner of the city first, then moving clockwise one neighborhood at a time.  

Phase 1 involved replacing the existing 25 mph signs on select roadways with new 20 mph signs. This started in early November 2025 and was completed in late December 2025!

Phase 2 involved installing new posts and additional signs. This started in February 2026 and was completed in summer 2026. 

FAQ’s

Which neighborhoods were changed first?

The rollout plan started in the northwest corner of the city first, then moved clockwise one neighborhood at a time.

When did the speed reduction go into effect?

Legally, the new speed limits went into effect on each street as soon as the signs changed: when the existing signs are replaced, or and when new signs were installed.

How long will did it take to rollout the program and new signs?

It took just over six months to complete the rollout. 

Will the new speed limits be enforced?

This campaign is about awareness and behavior change, not just enforcement. We’re asking for your cooperation to make our streets safer.

How much will the implementation cost? 

It is estimated to cost between $150,000 and $175,000 for the installation of the signs. These costs do not include staff time for educational outreach or maintenance. 

Email: Traffic Contact