Munich: How the resilience of the A99 should be increased – district of Munich

You can marvel at what the future may look like at the Munich-North motorway junction. On whisper asphalt, traffic rushes over long ramps coming from the A 9 coming from the direction of Nuremberg onto the east bypass of the A 99 and merging into a spacious and, above all, mostly trouble-free functioning four-lane route. At some point, traffic will also be able to flow smoothly about 20 kilometers further south as the crow flies on similarly modern ramps. It may be years before the Munich-South motorway junction is renewed and modernized – but the project is already playing a role in the considerations of Autobahn GmbH. “The motorway junctions have priority,” says spokesman Josef Seebacher. “Our goal must be to keep traffic on the A 99.” And accordingly to keep out of the state capital Munich.

The A 99 is one of the busiest routes in Central Europe

The eastern bypass is one of the busiest motorways in Central Europe, the traffic lifeline of the greater Munich area, loud and pulsating. More than 160,000 vehicles are on the transit route on peak days, and the pressure is no longer just on the A 99, but also on side arms such as the A 94 towards Munich and the Ebersberg district. In order to be able to keep traffic moving on these heavily used routes, commuters will have to put up with inconveniences in the coming year as well. You can already expect permanent construction sites. Because the federal government is constantly pushing ahead with the eight-lane expansion of the A 99 from the Munich-North junction to the Munich-South junction. After the section from the Munich-North junction to the Aschheim/Ismaning junction, the section up to the Kirchheim exit has now been completed with the commissioning of the Erdinger Strasse bridge over the A 99.

Starting next March, Autobahn GmbH will then tackle the next section in the eastern district of Munich: from the Kirchheim junction in a southerly direction towards Salzburg to just before the S 2 railway overpass near Feldkirchen. Work on the almost four-kilometer section is expected to last until autumn 2023 and cost around 130 million euros – including new bridges, drainage and necessary compensation areas. During the construction period, all traffic with a total of six lanes will be shifted to the eastern lane in the direction of Stuttgart, and the following year it will be the turn of the section in the direction of Stuttgart. However, Autobahn spokesman Seebacher does not expect severe traffic obstructions during the construction phase: “We designed it in such a way that there shouldn’t be any major disruptions.” However, according to the expert, a lot depends on the driving behavior of commuters. “Four kilometers is not long, if people drive with concentration, not much should happen,” said Seebacher. “But it is clear that the risk of rear-end collisions increases at high speeds.”

High speeds are not possible in the cloverleaf

The new construction phase is one of the shortest in the long history of the expansion of the A 99, which will probably last well into the 2030s or beyond. Planning for what is probably the most sensitive project in the east of the state capital will probably start in 2024: the conversion of the Munich-East motorway junction. This aging junction of the A 99 and the A 94 is completely overloaded, especially at peak times, and, unlike the Munich North and South motorway junctions, poses particular challenges. “The Ost motorway junction is certainly the most critical point because there are so many cross-corner connections here,” says Autobahn spokesman Seebacher. In other words: the East Cross is a junction in the classic cloverleaf shape and does not have long access ramps like the South and North Crosses, which allow high speeds, but rather narrow crossings that slow down traffic, “Ohrwaschl”, as Seebacher calls them. However, according to the Autobahn spokesman, the Munich-Ost junction is not about increasing the speed of traffic, but rather the performance of the entire structure. “Because all calculations show us that the cross no longer has any capacity.”

Coordination with the neighboring municipalities

However, it is not yet clear when the renovation will begin. First of all, a plan approval procedure must clarify the form in which renovation and expansion can take place. This must be clarified in close coordination with the surrounding municipalities, says Seebacher, and it must also be taken into account how the region is developing. “We simply have very dynamic growth here, a lot of new business is emerging. We have to include all of that in our planning.” In addition, there is noise protection, which is not only very planning-intensive, but also very cost-intensive.

Projects such as the eight-lane expansion of the A 99, which is actually a ten-lane one because the hard shoulder can also be used when traffic is high, must also be economically profitable, says Seebacher. Today it is no longer possible, even legally impossible, to simply lay out streets such as Fürstenrieder Straße in the state capital with four lanes, because planners may suspect that there will be more traffic at some point. So building in the dark is not an option.

Open detailed view

However, it is obvious that the pressure on the A 94 east of the interchange has increased and will continue to increase. Last but not least, the massive expansion of the Parsdorf commercial area, but also the connection to the airport tangent east have caused the volume of traffic to swell massively in recent years. Actually, the four lanes on the A 94 in the direction of Mühldorf are no longer sufficient. An expansion to six lanes will not be possible until the 2030s at the earliest, says Seebacher. Nevertheless, starting next year, construction will initially begin on the outskirts of the city from Kreuz Ost to Anzing, where the roadway will be completely replaced because the surface has reached the end of its service life. This measure is necessary because the roadway simply no longer holds, according to Seebacher.

However, he also reports that many people would turn to Autobahn GmbH with the expectation that the A 94 would be expanded quickly. “We receive letters every day asking when the expansion will finally take place,” he says; especially in this day and age, however, such projects must be approached sensitively. “There has to be a basic consensus because something like this is not entirely uncontroversial in society, as you can see from the current actions,” says the Autobahn spokesman, referring to the “Last Generation” protest movement, which repeatedly causes road blockades in the city Munich city center, but also on the motorways in the surrounding area, draws attention to their concerns.

The main traffic artery in the east of Munich will continue to be expanded, modernized and restructured in the coming decades. In four to five years, the first sketches for the eight-lane expansion of the A 99 to Ottobrunn are to be drawn up in a preliminary draft – and subsequently also to the Munich-South junction at the Hofoldinger forest. However, the section of the A 94 from the Munich East junction in the direction of the state capital will remain untouched. An expansion could lead to even more traffic being fed into the state capital, but the Mittlerer Ring could not bear any further loads, says Seebacher. “Everything that runs on the A 99 does not push into the city,” said the highway spokesman. “And the worse the A 99 runs, the more traffic there is in the city.” The focus of traffic planning in southern Bavaria is and remains this lifeline through the district of Munich.