The major focus of the project building a new southbound I-5 Puyallup River Bridge. The original was built in 1962 and is not up to current seismic standards. In addition, there was a curvature before coming on and off the bridge that did not meet current standards. It also limited the speed travelers could drive. The new bridge will be straighter and wider. A new northbound I-5 Puyallup River Bridge was completed and opened to traffic in 2018.
This section of I-5 sees frequent congestion. No surprise since the six-lane highway was opened in the 1960s when the average daily traffic was 21,600 vehicles. By 2019, the average daily traffic was just shy of 200,000 vehicles. Other sections of I-5 have expanded, with some as wide as 10 lanes.
I-5 is being widened in the work area, which is approximately 3 miles long, from three to four lanes. In the northbound direction side, WSDOT is adding more auxiliary lanes. This is to handle the congestion in the area, which occurs during the morning rush hour. A northbound HOV lane is also being added.
Other parts of the scope include demolishing the existing old I-5 bridges over the Puyallup River, demolishing and rebuilding an overpass that crosses I-5, replacing existing concrete pavement to the south of the new Puyallup River Bridge (between a 1-1.5 miles on north and southbound I-5), upgrading signing, illumination, stormwater collection facilities, and water quality treatment facilities.
Guy F. Atkinson Construction serves as the design-build contractor and Jacobs Engineering is the Engineer of Record on this project. As part of the contract, WSDOT requires the contractor to maintain a minimum of three lanes open in each direction during the daytime. Because lanes and ramps can only be closed at night when traffic volumes are significantly lower, the design-builder needs to develop and implement traffic staging that shifts travel lanes as new work zones are created. One example is that the design-build contractor moved both northbound and southbound travel lanes onto the new northbound I-5 Puyallup River Bridge. “They had to do this so the old bridge structures could be removed, and the new southbound bridge could be built,” Mitchell said.
Part of the work zone is over the river and several railroad lines. The team had to demolish the old northbound and southbound I-5 Puyallup River Bridges that go over the river and the railroad. Finding a way to do so that it did not disrupt the river, its habitat, and the railroad was another challenge.
Atkinson Construction, another member of the team, used a custom-designed piece of equipment that can be described as a “Beam Moving System” to pick and move the old existing bridge girders. The contractor used this equipment to pick up girders and move them to an area where they could be demolished, away from the river and the railroad. This reduced the risk of having debris from the demolition activity fall into the river or onto the railroad tracks. Atkinson performed this workaround in tribal fishing seasons.
“The machine was quite large and was painted a bright red/orange,” Mitchell said. “It caught the attention of travelers who then described it as a dinosaur.”
A unique element to this project is dealing with the longest prestressed concrete girder made in North America. The girder measures 223 feet long, almost 9 feet high, and more than 246,500 pounds. While it was manufactured locally in Tacoma, so it was a short trip to get it on site, “We had to choreograph it very carefully,” Mitchell said. The girder was moved in the middle of the night and set during the early morning hours of a Saturday in January.
The $325 million project is entirely state-funded. Funding for this project was approved by the State Legislature by the 2005 Transportation Partnership Program. It included a 9.5 cent gas tax increase. It was part of a revenue package approved in 2005 to fund 274 projects across the state over 16 years.
Work to build a new southbound I-5 Puyallup River Bridge began in February 2019. The contractors initial schedule had the new bridge and HOV lanes opened to traffic by the end of 2021. However, the date has been pushed back to the summer of 2022, which is also within the overall contract schedule between WSDOT and Atkinson.
Mitchell points to a few reasons for the new completion date. These include delays in the supply of required materials, a carpenters strike, and an approximately one-month halt on active WSDOT projects during the early stages of the pandemic.
When the project is complete, travelers will see reduced drive times through the area, especially during commute hours. Travelers who choose HOV or transit options will have a connected HOV lane to utilize. With vanpools and carpools being able to move efficiently through the corridor, there will be more reliability, which is expected to lead to an increase in ridership in multi-passenger vehicles. This will help ease demand in the general-purpose lanes and make the overall highway system work better for everyone.
Photos courtesy of Washington State Department of Transportation