Traffic remains debatable in Sammamish
Since its incorporation in 1999, Sammamish’s population has grown from approximately 35,000 people to over 66,000 today. With most residents relying on cars as their primary mode of transportation, road congestion and traffic have become topics of concern and debate.
In 2024, the city council worked with transportation engineering firm DKS Associates to study traffic solutions that would become part of the Sammamish Transportation Master Plan (STMP). DKS Associates concluded that the city’s traffic congestion is not chronic, meaning it is not congested outside of rush hour patterns. Though the city’s traffic does tend to spike during the morning and evening rush hours, 7-9 a.m. and 4:30-7:30 p.m.
According to Sammamish communications manager Angie Millar, most of the city’s traffic occurs on high-capacity urban roads, such as 228 Avenue, where approximately 15,000-24,000 cars pass each day. However, traffic volumes have declined since their peak in 2018.
In 2015, the city began tracking traffic volume in major intersections and several side streets. According to their data, traffic along 228 Avenue has declined since 2018. While much of the decline is attributed to the pandemic, volumes have yet to return to their pre-pandemic peak. However, with many technology companies returning to the office, including Microsoft set to return three days a week starting January 2026, those numbers may rise.
Still, some residents have expressed concerns over traffic. Save Our Sammamish (SOS), a local resident-led movement, has placed signs along city roads discouraging Town Center development, citing traffic as a significant reason for their opposition.
Sammamish Mayor Karen Howe knows that many in Sammamish are frustrated with traffic, and she is not unsympathetic. “It has everything to do with how [residents] feel,” she said.
To address the impact of growth and development on traffic, the city created the STMP. The plan includes recommendations for longer turn lanes for both right and left turns along 228 Avenue. In some cases, it recommends double turn lanes. In addition, the STMP recommends more roundabouts and additional traffic lights. The plan also aims to add more sidewalks and bike lanes to optimize safer movement and connections. According to Millar, aside from the STMP, the city is working on traffic initiatives like the Sahalee Way Corridor Improvements that are meant to improve transportation for drivers, cyclists, and pedestrians along Sammamish’s main thoroughfares. Millar also pointed to the traffic considerations included in the city’s Town Center Plan.
“With the Town Center being walkable, connected to bus, light rail in Redmond, there will be more options for people to get around than we currently have,” Millar said.
