View entire map. Project area is along I-5 beginning at SR 121 (Maytown Road, Exit 95) and south to SR 12 (Grand Mound).
View
drawing of I-5/SR 121 interchange improvements(Maytown).
Revisions to the I-5/US 12 Grand Mound interchange is a separate project.
Learn more.
Crews have dubbed hillside excavation south of Grand Mound the "big cut." Removing a portion of the hillside allows the roadway below to be re-aligned, creating a more gradual curve.
Secretary Paula Hammond at the controls of an excavator to officially break ground for the project in April 2008.
Project Facts
- More than eight miles of I-5 will be widened to three lanes in each direction.
- On-ramps and off-ramps will be improved.
- The major curve south of Grand Mound will be realigned.
October 2008
Read this week's construction activity and traffic impacts report.
Speed limit reduced to 60 mph
Construction is under way throughout the project area. Scarsella Bros. Inc. is the prime contractor for the project. Motorists need to exercise caution anytime they travel through a work zone.
Crews are making the most of good weather, working around the clock Monday through Saturday:
- To make room for a more gradual curve near Grand Mound, crews are removing a portion of the hillside south of Grand Mound. Work is on-track to be complete by mid-October.
- Crews are constructing stormwater treatment ponds throughout the project. The ponds reduce pollution from roadway water run-off.
- Crews are drilling shafts for new bridge piers near Prairie Creek.
- Outside shoulders have been widened through a portion of the project and work begins soon in the median.
Reconstruction of the I-5/US 12 interchange at Grand Mound is a separate project. Learn more.
Why is WSDOT
widening this section of I-5?
This project is one of a series of projects to provide a minimum of three lanes in both directions of I-5 from Centralia to Marysville.
The additional lanes provide much-needed congestion relief and improved safety. In 1968 an average of 17,000 vehicles per day used this section of the highway. Today, that number is nearly 80,000.
Upgrading the existing freeway on-ramps and off-ramps to meet current design standards also provides important safety improvements.
The End Result
When constructed, the facility will be a barrier-divided freeway providing three general-purpose lanes in each direction, where two lanes exist currently. The existing northbound and southbound truck-climbing lanes leaving the Maytown interchange will be retained, making a total of four lanes each direction in this area. Also, longer on-and off-ramps and on-ramps will provide more distance for vehicles to slow down and speed up.
South of the Grand Mound interchange, the realignment will provide a more gradual curve that can be negotiated safely at the posted 70 mph speed limit.
The end result is eight miles of I-5 that can safely move more vehicles, Additionally, the two rest areas within the project limits will be connected to the Thurston County sewer system.
Project Benefits
- Traffic Flow. The addition of one lane in each direction to I-5 improves traffic flow and relieves congestion.
- Safety. The project will realign the curve south of the Grand Mound Interchange on I-5, increasing the driver distance. The result will be improved driver comfort and safety.
What is the project timeline?
Construction started in April 2008. The project is scheduled to be complete in summer 2010.
Public Involvement
Prior to and throughout construction, WSDOT will keep the public informed through this Web site, the news media and a toll free project information line, 1-877-368-7623.
Environmental Protection
WSDOT is committed to preserving the environment and makes every effort to assess and minimize environmental impacts from our projects. A detailed analysis of the project's environmental impacts has been completed and an appropriate plan for mitigation of adverse impacts has been developed and documented as part of the Environmental Documentation and Environmental Permitting processes.
Within the project limits, I-5 crosses Beaver Creek, Scatter Creek and Prairie Creek. We carefully plan the roadway to minimize impacts to these important resources.
Please visit the WSDOT Environmental
Services Web site for more information.
Increasing safety is one of our priorities
For the length of the project, I-5 will be divided by a median barrier to eliminate the occurrence of head-on collisions. Where possible, steep side-slopes adjacent to the roadway will be "flattened" to reduce the severity of run-off-the-road collisions. Steep slopes that cannot be flattened will be protected with guardrail.
Many of the existing on- and off-ramps were not designed for the 70 mph posted speed limit. Where this is the case, on-ramps will be modified to increase the lengths available for vehicles to accelerate to freeway speed, and off-ramps will be modified to provide more length for vehicles to slow down when exiting the freeway.
The project also realigns the curve south of the Grand Mound interchange, increasing driver sight distance for improved driver comfort and safety.
Will this project impact tribal resources?
At WSDOT we seek to address the concerns of the tribal nations using the process outlined in Section 106 of The National Historic Preservation Act and the WSDOT Tribal Consultation Policy adopted in 2003 by the Transportation Commission as part of the WSDOT Centennial Accord Plan.
For more information visit our WSDOT Tribal Liaison website.
Financial Information
This project is funded through the following sources:
- 2003 Gas Tax (Nickel Funding) - $84,012,170
- Existing Funds - $4,297,618
- Other Agency Funds - $148,670 (Thurston County Waste Management)
- Total Funding Available From All Sources - $88,458,458
How can I get more information?
Contact:
John McNutt, Project Engineer
WSDOT Tumwater Project Office
821 Airport Court SE
Tumwater, WA 98501-6805
Phone: 360-570-6750
E-mail: gmtm@wsdot.wa.gov
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