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ACTT Workshop: Minnesota
|Figure 2. Proposed Design|
Figure 2 shows the proposed schematic design.
The I-35W and Highway 62 project has a long and controversial history dating back to its original design and construction during the 1950s and 1960s. Some of the project's design considerations prior to the ACTT workshop were:
The 2001 legislature directed Mn/DOT to develop alternatives that satisfied the following goals for the I-35W and Highway 62 project's reevaluation:
Mn/DOT provided a final report of the reevaluation to the Legislature on January 28, 2002. The report summarized the findings of the reevaluation, noting that the 2002 concept satisfied most of the project goals established by the Legislature.
The junction between I-35W and Highway 62 is one of the most heavily traveled and congested points in the metropolitan highway system. The I-35W and Highway 62 Commons, where I-35W and Highway 62 share lanes between the I-35W/Highway 62 east interchange and the I-35W/Highway 62/TH-121 west interchange, carries an average of more than 150,000 vehicles per day with 214,000 vehicles using the interchanges. Available capacity in the project area is exhausted during the morning and afternoon peak periods (approximately 6 hours per day), and the facility is congested for several hours a day beyond the traditional peak hours.
The capacity and operational problems are compounded by the many forced weaving movements and left exits in the Commons. These operational problems contribute to crash rates on the Commons that are up to five times higher than the average for metropolitan urban freeways. As congestion increases along I-35W and Highway 62, drivers attempt to bypass the area by using local streets, which results in increased congestion and accidents on the local street network. This aging freeway segment requires major, ongoing maintenance and cannot be brought up to today's design standards without complete reconstruction.
Reconstruction of the I-35W and Highway 62 project poses several challenges, including:
Legislative Requirements. The 2001 Minnesota Legislature identified several requirements for the current project (as noted above). Balancing these requirements resulted in the current design, which adds highway capacity and minimizes right-of-way takings. The proposed project staging will allow closures for major improvements to be held to less than the mandated 8-week maximum.
Traffic Operations. The I-35W and Highway 62 corridors run parallel in the Commons for nearly .75 mi (1.2 km), sharing lanes with a local access interchange and a railroad crossing within the Commons area. There are four other local access interchanges immediately adjacent to the Commons. Separating the two highways is vital to protect the operations of I-35W. Reducing or eliminating weaving movements is complicated because designers want access to be equivalent to the Deferred Project, yet right-of-way takings are to be minimized.
Right-of-Way. The existing right-of-way corridors are narrow and cut through fully developed residential areas. Furthermore, additional right-of-way takings are to be minimized. Shallow groundwater tables and the project area's geology preclude tunneling, and concerns over noise and visual impacts coupled with cost and winter maintenance activities rule out stacking the two highways in the Commons. These constraints led to the current design that separates the two freeways within the Commons yet minimizes the need for additional right-of-way.
Highway Traffic Volumes. Traffic volumes within the Commons are projected to increase from 214,000 to 306,000 vehicles per day by 2030.
Design Standards. The existing I-35W and Highway 62 do not meet current design standards at several locations:
The proposed design must meet a minimum 55 mph for both I-35W and Highway 62.
Aesthetic Enhancements. The Deferred Project identified aesthetic enhancements, and those recommendations remain valid. However, limited funding at that time prevented implementation of some of the enhancements. Mn/DOT's cost participation policy will guide negotiations with Minneapolis and Richfield to identify any enhancements and related city cost participation for the current project.
Municipal Consent. Minnesota state law requires approval from communities when state highway projects increase capacity, require right-of-way, or change access. Because the I-35W and Highway 62 project proposes to do all three of these, municipal consent is required from the Cities of Minneapolis and Richfield. Minneapolis policy makers continue to voice a preference for mass transit improvements over highway capacity improvements. (Note: Minneapolis disapproved the project at their September 3, 2004, council meeting.) Consent is anticipated from Richfield policy makers. (Note: Richfield approved the project at their August 10, 2004, council meeting.)
A prominent component of the I-35W and Highway 62 project development has been the public and agency involvement. Agency involvement has included both a Technical Advisory Committee (TAC) and a Policy Advisory Committee (PAC) as well as coordination with review agencies.
The TAC was established to provide technical input on the proposed project and included the following organizations:
This committee met frequently during the development of the project to discuss design concepts and related potential impacts/issues.
The PAC was also established and included the following organizations:
This committee met at key times during the project development process to discuss the design, potential impacts, and related issues.
Public involvement efforts included project newsletters, a Web site, numerous public open houses, and the public hearings held the evenings of the ACTT Workshop as part of the Minnesota Municipal Consent process. Additionally, numerous neighborhood meetings were held to discuss concerns regarding access, construction impacts, transit, and right-of-way acquisition.
The I-35W and Highway 62 project has a long history of development. The final report that reevaluated the project after the Legislature deferred the previous project was provided to the Legislature on January 28, 2002. It identified a concept that met the goals established by the Legislature for the project's reevaluation. This is referred to as the 2002 Concept. Design development that has been completed since the 2002 Concept is summarized in the following table.
|Refined Concept||February 2003 to April 2004||Evaluation of numerous concept alternatives was completed to address capacity, operational, and access questions.|
|Municipal Consent||April 2004 to September 2004||Selection of the preferred concept allowed further refinement to prepare a design layout that satisfied the requirements for Minnesota's Municipal Consent Statute. The design layouts were provided to Minneapolis and Richfield on April 16, 2004. A decision from the cities is required by September 15, 2004.|
|Mn/DOT Staff Approved Layout||May 2004||The design layout prepared for municipal consent continued to be developed and was submitted for official Mn/DOT review and approval on May 28, 2004.|
|Figure 3. View of Commons from TH 121 area looking east toward Lyndale Avenue|
|Figure 4. View of Commons from Wentworth Avenue looking at east interchange|
As part of the design development process, detailed traffic operations analyses were performed using computerized traffic simulations, and a graphic simulation was made available at several public meetings. A computerized visual animation was also prepared that depicted the existing and proposed conditions, and this was also presented at several meetings. Two frames from the visual animation, depicting the proposed conditions looking east along the Crosstown Commons from above the TH-121 area and from Wentworth Avenue, are shown in Figures 3 and 4.
Value Engineering is a program to improve quality, reduce project costs, foster innovation, eliminate unnecessary and costly design elements, and ensure efficient investments. Mn/DOT performed this ACTT Workshop to satisfy the Value Engineering requirements for the project.
During design development, SRF Consulting Group, Inc., incorporated the principles of Value Engineering to provide "continuous" Value Engineering to the project. Specific items that were analyzed in cooperation with Mn/DOT during design development included:
The results of these analyses have resulted in project costs being reduced by $14 million, which is already reflected in the $208 million project estimate. As design development continues through detail design, opportunities to further reduce project costs and enhance the quality will be studied and incorporated as appropriate.
|Bridge types||Steel versus concrete.|
Girder versus box.
Precast versus cast in place.
|Retaining wall types||Cast in place:|
|Storm water runoff||Water quality treatment.|
High flow diversions.
|Noise wall types||Wood.|
An Environmental Assessment (EA) and Section 4(f) Evaluation are required for the I-35W and Highway 62 project. The EA was approved by the FHWA on June 24, 2004. Because the area surrounding the project is fully developed, little impact to the natural environment is anticipated. However, two project impacts have been identified:
The current status of the project is presented in the following table.
|Design layouts provided to Cities of Minneapolis and Richfield.||April 16, 2004|
|Design layouts submitted for Mn/DOT staff approval.||May 28, 2004|
|Environmental Assessment (EA) approved.||June 24, 2004|
|Public hearing for comment on EA.||July 22, 2004|
|Public comment period on EA ends.||August 19, 2004|
|Municipal consent process scheduled to conclude.||September 2004|
|Interstate Access Modification Request (IAMR) is 80 percent complete.||Summer 2004|
|Final design is in progress.||Summer 2004 to Fall 2005|
|Bid letting scheduled.||Spring/Summer 2006|
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