From Portland Bureau of Transportation:
Portland City Council will consider a proposal on January 17, 2018, to reduce the speed limit on all residential streets to 20 miles per hour. If the ordinance passes, the Portland Bureau of Transportation will begin updating speed limit signs in February and expects to complete the process by April 1, 2018.
Residential streets make up around 70 percent of Portland’s street network and a large proportion of the city’s total public space. Reducing residential speeds is part of a broader citywide effort to support safe driving speeds on many types of streets.
20 mph speed limit would support safety
Most residential streets in Portland are narrow, have few marked crosswalks, and no bike lanes; given the tight space and lack of protection for people walking, using mobility devices, and biking, it is important that people drive slowly on residential streets.
The proposed 20 mph speed limit is part of Portland’s Vision Zero work to eliminate traffic deaths and serious injuries. Slower driving speeds help prevent crashes and, when crashes occur, reduce the harm that results. A pedestrian hit by a driver at 25 mph is nearly twice as likely to die compared to someone hit at 20 mph (AAA, 2011/2013, Impact Speed and a Pedestrian’s Risk of Severe Injury or Death).
Sign installation would start in February
If Portland City Council approves the new residential speed limit, PBOT will adjust speed limit signage beginning in February 2018 and continue through March. PBOT would double the number of residential speed limit signs, installing approximately 2,000 across the city. At some locations, existing signs would be relocated to maximize their effectiveness.
As is the case today, not every residential street would have a speed limit sign, but the 20 mph speed limit would be in effect on all residential streets.