The Karlsruhe–Basel high-speed railway (Ausbau- und Neubaustrecke Karlsruhe–Basel, literally "Upgraded and new line Karlsruhe–Basel") is a new line being built on the route of the Mannheim–Karlsruhe–Basel railway (Rhine Valley Railway). As a result of the project, the railway through the Rhine Valley is being upgraded to four continuous tracks and its operational efficiency will be increased as a result of the segregation of the various transport flows. The travel time for passenger services between Karlsruhe and Basel is to be shortened by 31 minutes. The project forms part of the Rotterdam–Genoa corridor and part of it is also part of the Main line for Europe (Magistrale für Europa in German and Magistrale européenne in French; Paris–Budapest).
Large parts of the line runs next to the existing Rhine Valley Railway. The planning of the line has been carried out progressively since the mid-1980s and the first section of the line between Rastatt Süd and Offenburg, was placed in operation in 1993. While several sections have been opened others are under construction or not started. The main components of the projects include the Rastatt Tunnel, the Katzenberg Tunnel and a western bypass of Freiburg for freight.
The date of the completion of the overall project is uncertain. The Federal Government considers a completion by 2030 possible. Planning services for sections 7.2. to 7.4 have been procured on the basis that it will be completed by the end of 2042.
The planned total cost is €6.172 billion (as of April 2013). Until the end of 2014, €2.27 billion had been spent on it. Deutsche Bahn estimated the total cost in 2015 as being €7.1 billion.
Route
Between Karlsruhe and Offenburg, the route runs closely parallel with the existing Rhine Valley Railway. Between Offenburg and Buggingen (south of Freiburg), it will run next to the A 5 as a new bypass of Freiburg. This section, which is designed to be operated at , is to be used in future by freight trains. A dense population and a reduction in the impact of freight transport were the key reasons for choosing this option. The existing line in this area, running from Offenburg through Freiburg to Buggingen, is to be upgraded for a running speeds of and will be used by all or almost all passenger trains.
In Buggingen, south of Freiburg, the freight bypass and the Rhine Valley Railway will meet up again and run in parallel to Schliengen. Between Schliengen and Eimeldingen the new line runs through the Katzenberg Tunnel, which with a length of 9.4 kilometres is the largest single structure in this section. The tunnel shortens the route for passenger trains, avoiding the winding route along a bank in this area. Later the passenger and freight tracks will run parallel to the Basel rail node.
The line between Rastatt Süd and Offenburg can be operated at . The newly built sections between Buggingen and Basel can also be traversed at this speed. The planned freight bypass of Freiburg is designed for . According to the federal government, although the speeds could have been increased to on some disconnected sections, this would not have had significant travel time benefits. The projected speed of , as opposed to the achieved on recent new lines, results from planning carried out in the 1980s. Between Rastatt station and Rastatt-Niederbühl the line continues to be double-track. This is to be resolved by the construction of the Rastatt Tunnel. The remaining section between Offenburg and Freiburg and further south is still being planned.
The 7 km-long Offenburg Tunnel is to be built under the city of Offenburg, which has 60,000 inhabitants. The German parliament approved the construction and financing of the tunnel on 28 January 2016.
History
Background
In the 20th century, there were demands for a new railway line to stimulate the central and southern Upper Rhine economically and to allow additional traffic to run.
A study in 1964 for the executive board of Deutsche Bundesbahn proposed the straightening of the line—particularly in Rastatt and Offenburg—to achieve significant travel time savings. (study completed in September 1964)
A program of upgrades for the Deutsche Bundesbahn network (Ausbauprogramm für das Netz der Deutschen Bundesbahn) that was submitted in 1970 provided for the construction of some 50 kilometre of new line by 1985 to relieve the most heavily used section between Rastatt and Offenburg. The route would branch off the existing Karlsruhe–Ettlingen West–Rastatt line near Muggensturm and bypass Rastatt to the east and Achern to the west. The new line would rejoin the existing line north of Offenburg. The town of Rastatt would have been connected to the new line by a shuttle service. The new section between the Rastatt area and Offenburg was allocated the second highest level of priority of the plan and was therefore targeted to be completed by 1985. The construction of the sections between Mannheim and Karlsruhe and between Offenburg and Basel would have been completed after 1985.
While planning in the first half of the 1970s still provided for an almost direct new line between Karlsruhe and Basel with a large loading gauge (for the transport of trucks in enclosed high-speed wagons), it was updated in the second half of the 1970s. In mid-July 1979, Deutsche Bundesbahn plans announced that the route would no longer consist of a completely new line. Instead, the new line would to a large extent be placed next to the existing line.
In 1990, around 320 trains ran on the existing line on each weekday (total of both directions). In 1992, the existing line between Offenburg and Basel carried approximately 130 trains per day in each direction. The line was considered overloaded, particularly towards Basel, which was calculated as having a capacity of around 110 trains per day. The Federal Transport Infrastructure Plan (Bundesverkehrswegeplan) 1992 forecast an increase in the number of trains south of Offenburg from 133 trains (as of 1992) to 190 trains per day and direction.
Planning
As a result of intermodal economic and business analysis carried out by the Federal Ministry of Transport, the “(Karlsruhe–) Rastatt–Offenburg–Basel railway” was added the Federal Transport Infrastructure Plan 1980 (BVWP 1980). As part of the Stufe I (“level I”) of the BVWP 1980, the first work would have been a new double-track line between Rastatt and Offenburg to be built by 1990 for DM 960 million. In addition, the plan provided for an upgrade to three-tracks between Offenburg and Basel with improvements to the track. A total of DM 2.5 billion (1978 prices) would have been invested in the project. The Federal Transport Infrastructure Plan 1980 also provided for an additional track between Offenburg and Basel in the period after 1990 as part of Stufe II (“level II”). At the end of 1980, the planners envisaged initiating the first planning approval procedure in 1981. A planning group for the upgraded and new line was established in Karlsruhe in 1981. The regional planning approval procedure for the Karlsruhe–Basel section was carried out during 1983 and 1984.
In the mid-1980s, the section between Offenburg and Rastatt was particularly congested. Around 290 trains ran daily through this bottleneck and more on peak days. The then Deutsche Bundesbahn described traffic on the section as exceeding capacity by 30 percent. Traffic was expected to increase to 350 trains per day by the end of the century. It was intended at that time that a 70 km-long new railway line would be built between Durmersheim and Offenburg parallel to the existing line designed for operations at 250 km/h, an upgraded line would be built between Offenburg and Schliengen for operations at 200 km/h (this would have included measures for maximising capacity), an approximately 20 kilometer-long new line would be built between Schliengen and Basel and a planning study would be undertaken for a third track south of Offenburg. The project would have cost 2.3 billion DM and have been completed in 1995. The cost–benefit analysis for the Federal Transport Infrastructure Plan showed a benefit-cost ratio of 5.4 for the overall Karlsruhe–Basel project. (10 A4 pages)
Preparations for the land use and planning approval process began in 1984. The first regional planning process, for the Karlsruhe–Offenburg section, was successfully concluded in the autumn of 1984. Detailed planning commenced immediately and an initial planning approval process for the Achern area was opened in 1985. It was intended that the upgrade project, under which almost 80 percent of the route would have been made operable at 200 km/h, would be finalised if possible by 1994.
In February 1988, the regional planning approval process was commenced for the Schliengen–Basel section.
The Federal Transport Infrastructure Plan 1985 provided for four tracks between Karlsruhe and Offenburg. In the section continuing to Basel the capacity of the two existing tracks would be upgraded and an option for a third track would be considered. Between Offenburg and Schliengen, the line could be upgraded for 200 km/h with relatively little work. The section with projects listed as "urgent requirements" in the BVWP 1985 included the so-called 1. Stufe der ABS/NBS Karlsruhe – Offenburg – Basel ("level 1 of the Karlsruhe–Offenburg–Basel upgraded and new line") with an investment cost of DM 1,678 million. The section covering planning provided DM 532 million for a second stage.
Due to the proposed new and upgraded rail links through the Alps (between Switzerland and Italy and between Austria and Italy), planning for the Karlsruhe–Basel section was checked for adequate capacity around 1989. Although the upgrading of the existing line to enable operations over two tracks at was not listed in the Federal Transport Infrastructure Plan 1985, this specification had already been adopted in the planning. Deutsche Bundesbahn took over the planning in 1989. It developed three groups of options that could be combined for the section between Freiburg and Basel: along the Rhine Valley Railway, along the autobahn and bypass routes. The 1990 planning studies produced forecasts of costs, depending on the option, of around DM four billion, plus or minus 15 percent. Considerations of passenger traffic bypassing Freiburg with a route that was about 7.5 kilometers shorter and would serve the city with a station at the intersection with the Freiburg–Colmar railway at Hochdorf have since been discarded. This bypass of Freiburg would instead serve only freight trains and special trains bypassing Freiburg.
In the second half of 1993, a continuous four-track upgrade of the Rhine Valley Railway was an element of the draft Federal Transport Infrastructure Plan 1992. In addition to Switzerland's decision to implement NRLA, the building of the Betuweroute in the Netherlands, Austria's introduction of a ban on driving trucks at night on 1 December 1989 and the introduction of the European Union’s internal market on 1 January 1993, the wish to improve rail passenger services was a major reason for its adoption. Construction of a third track on the section was discarded due to insufficient capacity and operational difficulties.
In mid 1986, DB calculated that if construction began in the following year, the project could be completed in 1994. A new line would be built between Rastatt and Offenburg and on the remaining section to Basel the maximum speed would be raised to at least 200 km/h (with occasional line improvements).