The value of being an officially designated Interstate is significant. Primarily due to the greater allocation of transportation funds, which in turn permits more favorable assignment of asset and service resources such as guard rails and snow plows. Proximity to an interstate highway can also lure large employers who prefer interstate access.

US 41 is a 175-mile stretch of highway connecting two crucial economic regions in Wisconsin: the Greater Milwaukee Area, and the densely packed manufacturing belt of the Fox River Valley. Traffic congestion along US-41, combined with the route’s location in relation to other interstates connecting Chicago and industrialized Wisconsin, led to US-41’s change in designation. As part of its upkeep and modernization process, the condition of the roadway needed scrutiny to ensure it was up to Interstate specifications.

The Wisconsin DOT called upon Continental Mapping to conduct high accuracy photogrammetric mapping of the corridor. Due to its length, this award constituted the largest single work order in WisDOT history.

The WisDOT US-41 specifications were standard for Wisconsin DOT projects – 3D planimetrics, DTM, contours.

The project consisted of 337 stereo models flown at 1,000’ AMT (0.2’ vertical accuracy). Upon delivery, the data was accepted with no correction requests – first time right.


US Interstate 41 Photogrammetry


Wisconsin Department of Transportation

Aerial photogrammetric image of US Interstate 41 interchange in Wisconsin.