The Deutsche Bahn AG (DB) intends to fully extend the Rheintalbahn to four tracks on the segment between Karlsruhe and Basel. The extension has already taken place between Rastatt and the Central Station in Offenburg. The segment 7.1 (Offenburg Süd - Hohberg) is currently in the plan approval process. AS&P had previously conducted a comprehensive technical study on the urban planning impacts of the extension in 2006. A realization of the DB's intended massive extension of the line indicates that an around 4km stretch leads directly through Offenburg. This would bring about the demolition of around 26 residential buildings and 150 garages to make room for the line and the surrounding collateral noise barriers with a height of around 10m. The City of Offenburg rejected this proposal and, from their part, supported the development of a downtown railway tunnel passing underneath the city. Since the spring of 2008, AS&P has supported the City of Offenburg with their expertise to protect the city's interests within the scope of the ongoing plan approval process. A detailed expert's opinion on the specific extension plans of the DB forms an important building block of the city's technical and political argumentation and thus contributed to the around 40,000 official objections at the Freiburg Regional Council by citizens against the Deutsche Bahn's plans.