State Trunk Highway (STH) 121

STH 121 is a major state highway running through west-central Wisconsin and required a 14.75-mile upgrade between Gilmanton and Independence counties. ISG was appointed by the Wisconsin Department of Transportation (WisDOT) to lead design engineering that met WisDOT Plans, Specifications, and Estimates (PS&Es). This also included advancing PS&E requirements without a formal contract—removing extra charges to WisDOT. To meet environmental compliance standards, ISG’s in-house environmental team achieved Wisconsin Department of Natural Resources approval, documented Preliminary Concept Evaluation, conducted a Level 2 wetland delineation, and completed a Phase 2 Haz-mat report. The project reflects ISG's competence in delivering a successful WisDOT roadway improvement project that meet transportation needs and environmental standards.

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