Karlsruhe tram tunnel opens

[U-Bahnfreund]

Today, the main part of the €1.5b "Kombilösung" project, the tram tunnel under Kaiserstraße and Ettlinger Straße, opens.

The controversial tunnel has been subject to two referenda and was under construction for almost 12 years and planned in various iterations since the 1980s.

For reference: Karlsruhe track map

It sees the removal of aboveground tram tracks in the east-west Kaiserstraße pedestrian zone, between Durlacher Tor and Europaplatz, which saw up to 48 trams and tram-trains per hour per direction prior to the start of the construction works, as well as on Ettlinger Straße southwards from Marktplatz to Augartenstraße. In addition, the east-west Kriegsstraße axis was rebuilt featuring new tram tracks and a road tunnel (the latter is not yet finished). The Kriegsstraße tram tracks also replace parallel tram tracks through Baumeisterstraße.

The Kaiserstraße and Ettlinger Straße tracks are replaced by tunnels under the same streets (2.4 km east-west, 1 km south). At Marktplatz, there's a *not* grade-seperated three-leg junction, that will probably hamper capacity in the long run. There are six stations: Europaplatz, Marktplatz (with two parts), Kronenplatz, Durlacher Tor on the east-west axis and Ettlinger Tor and Kongresszentrum on the southward branch.

As part of this opening, the tram and tram-train network is being greatly revamped: partly this includes reinstating old routings that had been diverted long-term due to the construction works, as well as actual new routings, which some say is an improved network, while others criticise them as just a cost-cutting measure.

(Lines 1-6 and S2 actually run according to the new timetable from today, Saturday 14:00, while all the other S tram-train lines start running in the tunnel only from Sunday morning tomorrow, because they're integrated with DB so aren't as flexible)

Changes to the lines:

Spoiler: Detailed break-down of line changes

East-west lines S2 (Rheinstetten - Spöck) and S5/51 (Wörth/Germersheim - Pforzheim) don't change much, but run underground now. Because there's no direct exit from the tunnel to Karl-Wilhelm-Platz, S2 now runs on a slightly modified route via Tullastraße.

East-south line S4 (Karlsruhe - Heilbronn - Öhringen), S7 (Karlsruhe - Achern), S8 (Karlsruhe - Freudenstadt/Bondorf) and 2 (Wolfartsweier - Knielingen Nord) don't run on the long-term diversion via Rüppurer Straße and Tivoli, but use the traditional route via Marktplatz and Ettlinger Straße again, just underground now.

North-south lines S1 (Hochstetten - Bad Herrenalb) and S11 (Hochstetten - Ittersbach) use the traditional route via Ettlinger Straße instead of Rüppurer Straße/Tivoli as well, but they head west from Marktplatz. Only the peak S11 express runs stay aboveground and now run from Albtalbahnhof to Europaplatz via Karlstraße, as they use high-floor trams that can't enter the tunnel. These runs are now designated as S12.

The existing peak line S52 from Germersheim now runs via Ettlinger Straße to Marktplatz. The underground station there has an extra turn-back platform, that's new compared to the aboveground tracks.

In the city tram system (lines 1-6) there are greater changes, apart from line 2 mentioned above:

Line 1 from Durlach will now run underground under Kaiserstraße, but from Europaplatz it will head to Heide (previously line 3), instead of Oberreut.

Line 3 in turn doesn't run to Heide anymore, but takes over from line 6 between Daxlanden and Europaplatz. From Tivoli it is extended via Rüppurer Straße and Durlacher Tor to Rintheim (the latter previously line 5). Because line 3 is now the only line serving Karlstraße (apart from the infrequent S12 express), it will run every 5 minutes between Europaplatz and Tivoli during peak hours. On Rüppurer Straße, where line 3 is alone as well, there will no extra trams (so it's 6 tph instead of 17-21 tph until today).

Line 4 from Waldstadt is rerouted from Durlacher Tor via the new Kriegsstraße tracks to Europaplatz and then on to Oberreut (previously line 1). For Waldstädters this means losing the direct connection the central station as well as the central tram stop in the pedestrian zone (Marktplatz). Also Oberreuters now need to change to get to Marktplatz.

Line 5 switches from the Baumeisterstraße to the new tracks on Kriegsstraße and continues from Rüppurer Tor via parts of line 6 and then from Tullastraße to Durlach station.

Line 6 is withdrawn, being replaced between Daxlanden and Karlstor by line 3, between Karlstor and Tullastraße by line 5 (on Kriegsstraße instead of Baumeisterstraße) and between Tullastraße and Hirtenweg by line S2.

Some links:
- new map (PDF)
- cab ride video
- official website of the project
- news report by SWR

 

[edwin_m]

Thanks for the information. They were indeed talking about this when I was involved with the Karlsruhe people in some other projects in the 1990s.

How many trams per hour actually operate through the tunnel? If it's near the original 48 then is this some kind of record for frequency in a tunnel? Is the tunnel signalled and fitted with train protection?

Took a quick skim of the links but couldn't see any answers to these, although it does mention a tram every minute at peak times.

 

[U-Bahnfreund]

There are about 24 tph on the western leg, 18 tph on the southern leg and 29 tph on the eastern leg. There might be some additional extra trams during peak hour.

Yeah, the tunnel has signals and train protection, and I watched a number of videos where tram drivers talked about how this was very new to them: I believe in tram mode, there had been no real signalisation apart from like general traffic-flow signals at intersections. (The tram-train drivers of course are familiar with signalling from DB tracks.)

 

[edwin_m]

There are about 24 tph on the western leg, 18 tph on the southern leg and 29 tph on the eastern leg. There might be some additional extra trams during peak hour.

Yeah, the tunnel has signals and train protection, and I watched a number of videos where tram drivers talked about how this was very new to them: I believe in tram mode, there had been no real signalisation apart from like general traffic-flow signals at intersections. (The tram-train drivers of course are familiar with signalling from DB tracks.)

Thanks for the information.

I agree normal tramways don't have signalling except at junctions with other tramways or roads - even somewhere like Stuttgart where the standard-gauge light rail system seems much "heavier" than Karlsruhe. I would have expected signalling in the tunnels but thanks for the confirmation. I would also have been surprised if 40+TPH was to be operated on a route with signalling, as line of sight gives more capacity although at lower speeds.

 

[jonty14]

I was there last week and was wondering where the trams were. All the infrastructure is still on Kaiserstraße including quite new modern tram stops which seems a waste.

 

[edwin_m]

I was there last week and was wondering where the trams were. All the infrastructure is still on Kaiserstraße including quite new modern tram stops which seems a waste.

They'd have to keep it in good condition because it was carrying a very large number of trams right up until it closed. Some of the stop furniture can probably be re-used elsewhere.