MnDOT TH 13 Improvements

Summary

Kaskaskia Engineering Group, LLC (KEG) provided environmental services for the Trunk Highway (TH) 13 Corridor Evaluation and Dakota Improvement from US Highway 169 to east of Nicollet Avenue in the towns of Savage and Burnsville, Minnesota for the Minnesota Department of Transportation (MnDOT). The project involved the study of the highway corridor to determine the ultimate corridor vision and potential improvement plan, specifically for the intersections of TH 13 and Dakota Avenue, Yosemite Avenue, and Vernon Avenue

Project

TH 13 serves as an east-west principal arterial roadway and provides a highway connection between two major river crossings in the area. The TH 13 Improvements project is a multi-phase roadway corridor project with a total length of approximately eight miles. It includes several at-grade and grade-separated interchange improvements to improve both safety and travel within the corridor. The project was separated into a first construction project area (Dakota Avenue) and a corridor-wide evaluation area for future projects.

KEG provided environmental services in support of the project. Tasks included participating in environmental strategy sessions on defining the new Hybrid Environmental Assessment (EA) process; preparing portions of the Social, Economic and Environmental (SEE) Impacts sections related to land use, community, economic, environmental justice, and wetlands and Waters of the U.S.; conducting fieldwork to evaluate the first construction project area and corridor-wide project area for the presence of wetlands and Waters of the U.S.; and performing the quality assurance/quality control for the draft and final Hybrid EA.

The Hybrid EA is a brand new environmental process, utilizing some of the approaches from a Tiered Environmental Impact Statement (EIS), in order to gain environmental clearance for both the corridor vision and the first construction project within the same EA. KEG provided strategic guidance and process tools to assist with advancing the EA in an accelerated fashion.

As part of the fieldwork, Level 1 delineations were completed for the entire corridor-wide project area. The Level 1 Wetland Delineation indicated the potential for nine wetlands and one stream located within the corridor-wide footprint. Level 2 Wetland Delineations were completed within the first construction project area. The Level 2 Delineation, completed in August 2020, within the first construction project area, verified the presence of 13 wetlands, seven ditches with wetlands, and three streams. The Level 2 wetland delineation report was reviewed and approved by the Minnesota Wetland Conservation Act (WCA) Local Government Units (LGUs), which are Scott County and the Minnesota Department of Transportation (MnDOT) Metro District. The Level 2 wetland delineation was also reviewed and approved by the U.S. Army Corps of Engineers. The WCA/USACE permit application will be based on the approved wetland boundaries and types.