A bypass of the southern terminus of PA 402 was proposed in 1991 to deter traffic off the congested intersection with US 209 and US 209 Bus. in the village of Marshalls Creek. The same year, the Pennsylvania Department of Transportation (PennDOT) got involved in the feasibility study, and preliminary engineering work was finished in 1995. The project, notorious for delays, first hit a barrier in 1997, when a pair of species of endangered fish (Bridle shiners and Iron-colored shiners) were found in Marshalls Creek. In 2000, after a Final Environmental Impact Statement had been completed, the route was approved by the Federal Highway Administration. In 2004, a delay was created again, when pyrite was found in the area, which led to engineers finding a way to not harm the fish in Marshalls Creek.