February 2010
- Questions or comments about ongoing construction on I-5 between Grand Mound and Maytown, including work at the Grand Mound interchange? Visit the project page or contact Project Engineer MaryLou Nebergall at 360-570-6752.
- This project improves the I-5/US 12 interchange at Grand Mound in Thurston County.
- The new US 12 overcrossing will be slightly north of the existing overcrossing, providing two important benefits:
>Minimal traffic impacts during construction because the new bridge will be built "off-line."
>Reduction of the overall time it takes to rebuild the interchange.
- View an engineering drawing (pdf 407 kb) of the new interchange configuration.
Why is WSDOT
replacing this interchange?
Rebuilding the I-5/US 12 interchange at Grand Mound improves mobility and safety.
The End Result
The interchange configuration will be modified as shown in the attached "Proposed Realignment" file. Both loop ramps will be eliminated. Traffic signals will be installed at both ramp intersections resulting in a typical "diamond" interchange configuration. On the east side of the interchange, the two existing exits from northbound I-5 will be consolidated to one exit point.
The alignment of the US 12 roadway across the interchange will be shifted to the north. This will allow both bridges (over I-5 and the railroad) to be replaced with minimal impact to traffic.
Project Benefits
- Safety. The project realigns and lengthens on- and and off-ramps at the interchange to provide the more room for vehicles to safely enter and exit the highway, adds signals and improves driver sight distance.
What is the project timeline?
The project is currently in the design phase. Construction is scheduled to begin in late 2010.
Financial Information
This project is funded through the following sources:
- 2003 Gas Tax (Nickel Funding) - $45,183,636
- Total Funding Available From All Sources - $45,183,636
How can I get more information?
Contact:
Bill Elliott, Project Engineer
WSDOT Tumwater Design Office
PO Box 47446
Olympia, WA 98504-7446
Phone: 360-570-6606
E-mail: elliotb@wsdot.wa.gov
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