These projects included a mill and overlay of TH 149 from Interstate 494 to George Street through Mendota Heights, West St. Paul, and St Paul; a mill and overlay of TH 13 from Cherokee Heights Boulevard through Mendota Heights, West St. Paul, and St Paul; and a mill and overlay of TH 149 from George Street through St. Paul to MN 5. 

Isthmus led the design of all the pedestrian facilities, sidewalks, and driveways along the entire corridor to meet the Americans with Disabilities Act (ADA) requirements.  Curb lines, roadway geometry, and intersection modifications were made to not only comply with the ADA but to improve multi-modal functionality along the corridor.  The project ADA design included over 30 intersections and 2.5 miles of sidewalk. 

Plans were included for a shared bike lane in the northbound direction and a dedicated bike lane in the southbound direction from TH 5 to George Street. and for a sidewalk addition from Cherokee Heights Boulevard to Chippewa Avenue.

Isthmus also prepared the signing and pavement marking designs to accommodate sidewalk and bike lane additions, crosswalks, and roadway use.  Signing was updated at Interstate 494/TH 149 ramp area to comply with current design standards and practices, and appropriate bike lane signage was installed at new bike lane areas. Signs for the remainder of the project were salvaged and reinstalled as needed to accommodate impacted signage due to drainage and ADA improvements.  Pavement marking was designed for the entire length of the project which included crosswalks, bike lanes, and turn lanes in both rural and urban portions of the project.

MnDOT Project Page:


  • Signing & Pavement Marking
  • ADA Compliant Design
  • Quality Management



Owner: Minnesota Department of Tansportation (MnDOT)

District Location: MnDOT Metro

Year of Completion: 2019

Approximate Total Project Cost Through Construction: $39 million (including bridge)

MnDOT Project Number: S.P. 6223-20 & S.P. 1917-45 

2020 Engineering Excellence Grand Award Winner!

The American Council of Engineering Companies of Minnesota (ACEC/MN) awarded this project a 2020 Engineering Excellence Award which recognizes engineering achievements that exhibit the highest degree of merit and ingenuity.

Isthmus Engineering
500 Jackson Street
Saint Paul, MN 55101
(651) 288-0300
.(JavaScript must be enabled to view this email address)
When Work Works Award Winner
©2022 Isthmus Engineering  |  Minneapolis Web Design by Creative Arc.