Southwest Arterial

Southwest Arterial


WHKS provided final design services for a portion of a 6.1-mile four-lane divided freeway with Priority One access control on a new alignment between US Highway 61/151 and US Highway 20.

WHKS prepared plans and specifications for the following segments:

Menards Frontage Road

The Menards entrance was relocated and a new frontage road was constructed with improvements to the existing intersection at Old Highway Road and US 20. The project included additional dual westbound left turn lanes on US 20, new traffic signals, retaining walls to minimize right-of-way impacts, and the development of a traffic control and staging plan to construct the project under traffic. The project included 44,000 SY of PCC paving, 12,000 SY of temporary paving and 1,900 LF of new water main.

US 20 Interchange

The US 20 Interchange provides access from US 20 to Industrial Center West and the Dubuque Metropolitan Area Landfill to the west and the beginning of the Southwest Arterial to the east. The features at this interchange include the gateway bridge over US 20, a multi-lane roundabout intersection at the eastbound ramps of US 20, Chesterfield Drive and Southwest Arterial, reconstructed bridges on US 20 over Catfish Creek, and ramp bridges over Catfish Creek.

North Cascade/English Mill Connector Road Interchange

This segment included designing an interchange on the SW Arterial with roundabouts for ramp terminals and 1.2 miles of roadway on new alignment. The project also included design and preparation of plans for culverts, storm sewer, grading, paving, and signing.


  • Alternative alignment analysis
  • Roadway and bridge design
  • Roundabout analysis and design
  • Traffic signal design
  • Retaining wall design
  • Utility design
  • Drainage design
  • Topographic and construction survey
  • Construction administration
  • Construction observation