There is a bottleneck for passenger and freight traffic between Aarau and Zurich. For this reason, Swiss Federal Railways (SBB AG) is planning measures to drive forward the urgently needed development of services. 

SBB AG is building the new Birr - Mägenwil line as the next step in the development of services. In addition, the track facilities and Mägenwil station will be expanded and noise protection measures implemented. 

Approximately CHF 160 million from the budget for the "Expansion step of the strategic development program" (STEP) was approved for the Rupperswil - Mägenwil performance enhancement project.