Meeting the Paving Challenges of the I-405 Project Head-On

If you're a paving contractor in the Northwest, you know the weather is predictably unpredictable. It's rare to have a full week of optimal paving conditions. That's certainly been the case during the construction of the I-405 widening project, as contractors press on in an effort to complete their work before the construction season grinds to a halt.

Add a nighttime paving schedule, with cooler temperatures and a restricted paving window, and a stiffer liquid binder, required by the Washington State Department of Transportation (WSDOT), and you know delivering the project to meet the customer's expectations will require a concerted effort of all involved.

The I-405 widening project is all part of WSDOT's "Moving Washington - A program to fight congestion," which is designed to add capacity and efficiency, and improve overall safety for motorists. The corridor currently accommodates 800,000 people daily. As each constructed project builds toward the master plan, more people are efficiently and safely accommodated. Eventually, the completed project will accommodate up to 1,540,000 people daily.

The 10-year "Moving Washington" plan is WSDOT's vision of investments and priorities in integrate new capacity, efficiency tools and commute options to address congestion issues and improve the overall performance of the state's transportation system.

WSDOT's vision for the future is: "To enhance our economic vitality and personal mobility while safeguarding the environment, by continually improving our transportation system. A balanced, efficient and reliable transportation system can meet our increasing population needs and allow us to stay competitive in a global economy for the years to come."

Effective and efficient transportation is critical to maintaining the state's economy, environment and quality of life.

Since the master plan for I-405 improvements was adopted in 2002, WSDOT has focused on the worst congestion chokepoints first, coordinating all transportation modes into a working system.

Through several funding mechanism, the state has invested nearly $1.5 billion into the corridor to date. The I-405 Corridor's Renton Stage 1 Widening and Renton Stage 2 Widening projects are a continuation of the master plan strategy to address congestion chokepoints.

Renton Stage 2

As part of the I-405 corridor improvement, construction of the I-405 - I-5 to State Road (SR) 169, along with the SR 515 Interchange Project (the entire project is also known as Renton Stage 2 Widening) is currently underway.

The $83.6 million project includes a new half-diamond interchange on I-405 east of the I-405/SR 167 interchange at SR 515 (Talbot Road) to improve access to downtown Renton and relieve traffic demand on the I-405 interchanges at SR 167 and SR 169.

The Stage 2 project also includes the construction of one additional travel lane in each direction of I-405 between SR 167 and SR 169, as well as building a new Benson Road Bridge over I-405. Renton Stage 2 will add another 1.8-mile travel lane in both directions when completed.

The I-405 - I-5 to SR 169 Stage 1 Widening Project was recently completed, adding a 3-mile northbound and 3-mile southbound lane to I-405 between I-5 and SR 167, along with additional improvements to SR 167 between I-405 and SW 41st Street.

Work on the Renton Stage 2 project is managed by the I-405 Corridor Design-Builders (CDB), which is a joint venture of CH2M Hill and Gary Merliono Construction Company. ICON Materials, a division of Oldcastle Materials, is delivering the asphalt paving portion of the Stage 2 project.

ICON, a leading Northwest contractor for infrastructure and transportation construction, and paving, as well as a supplier of aggregates, sand, gravel and asphalt, was subcontracted to construct the extra travel lanes on I-405, along with milling and paving work required on the interchange roads.