I-35W/I-494 Interchange Improvements
The recommended "turbine interchange" concept layout for the I-35W/I-494 interchange.
Much needed interchange improvement
The 35W/494 interchange is one of the most congested, unsafe interchanges in the State of Minnesota. It was designed in the 1950's, constructed in the early 1960's, with very few modifications or improvements since that time.
The interchange is congested well over 30% of each and every day, carrying nearly 500,000 vehicles daily through the now over-capacity interchange, with many vehicle crashes occurring in and around the area.
The 2001 Final Environmental Impact Statement (FEIS) recommendation totally redesigned the interchange. The 2001 FEIS preferred alternative involved a multi-level interchange at a cost of close to $300 million. The design was also difficult to construct in a performance-based, phased approach.
These resources are found on MnDOT's I-494 and I-35W project Web page.
- Interchange History and Need Report
- Preliminary design report produced in 2010
- Executive summary with alternative concept figures
- Preliminary design report appendices (69 MB)
- Storm water alternatives study (40 MB)
- Information presented at the open house, April 28, 2014
The MnDOT 2009 Rescoping Project is a very welcome new approach to the interchange design. The performance-based design process, now endorsed by the Federal Highway Administration and the Minnesota Department of Transportation, is very much needed in these fiscally-constrained times.
The Rescoping Project recommended a "turbine interchange" concept layout as shown above. The turbine design has the project advantage of the ability to be constructed in phases. This phased approach has a much higher possibility of being funded by federal, state, regional, and local agencies. The turbine design is projected to be completed for $237.6 million versus the $270.6 million cost for the 2001 preferred alternative. The 2001 preferred alternative, besides the additional cost, could not be done without a substantial amount of reconstructed sections if completed in phases.
Phase I of the 35W/494 interchange improvement could be constructed for $34.5 million (construction cost only). It would cost $75 million for the Phase I interchange project that would include a bus rapid transit station with a park and ride ramp. This is an important project for the Metro Area, both for traffic and development potential.
There are some aspects of a phased interchange project that could be moved forward quickly, including:
- NEPA Review
- Staff Approved Layout
- Interstate Access Request
This work could be completed in approximately one year from an initial start date. That start date is undetermined at this time.