Rainier Avenue construction reaches another milestone

Published 7:30 am Friday, January 9, 2026

The latest construction phase on Rainier Avenue in Renton is coming to a close and is expected to be finished soon.

Phase 4 of the 20-year construction project will conclude later this month, weather permitted, Renton city officials said. Paving is now complete and drivers can expect only intermittent closures for median and striping work.

The current phase, which began construction in March 2023, is focused on the section of Rainier Avenue between South 3rd Street and NW 3rd Place. The phase will include sidewalk widening with streetscaping, pedestrian-scale lighting, extension of the Lake Washington Loop Trail, pedestrian-activated traffic signals, upgraded existing traffic signals, transit improvements, including an extended business access and transit lane, and planted buffer strips and landscaped medians along the stretch of road.

Renton Transportation Division Director Jim Seitz said Rainier Avenue is one of the older regional corridors around the Puget Sound, and he estimated it was built in the 1920s. In the early 2000s, the Renton City Council began looking at ways to improve the corridor for the future.

“It was built for a different time, different type of vehicles,” Seitz said. “We really needed to modernize the corridor.”

The city was experiencing high accident rates along the corridor at the time while vehicles were trying to access businesses along the corridor. Seitz said the five lanes along the corridor were also not enough to accommodate the vehicles and transit on the road.

“Transit has really evolved in the Puget Sound area. We have a lot more buses on the road today and even back then,” Seitz said. “In the future, we are going to have a new transit center right there on Rainier Avenue and Grady Way, so we really needed to plan for all that.”

A transportation study conducted by the city in 2005 found the corridor needs seven lines with an outside lane dedicated to transit and better managed access to businesses. Shortly after the study, the city began the multi-phased project.

The next phase of this project will continue the road improvements up to the city limits and mainly will deal with airport frontage instead of businesses. Seitz said design work for the next phase may take a few years, along with having to buy property, resulting in the construction possibly not beginning for another five years.

Seitz said a project like Rainier Avenue is not much different from other projects the city does except for the scale of the work.

“We don’t do a $50 million project that often. It’s one of the bigger projects we’ve done in the city,” Seitz said.