Central crossing at the Max-Bauer-Allee washed out. Motorists and buses affected. Repairs may take up to two weeks.
The technicians from Hamburg Wasser notice the alarm signal at around 4:35am on Monday. A pressure drop has occurred in one of the main lines below the crossing of Max-Brauer-Allee and Holstenstraße. Water is bursting from the pipe and is washing out the street over a length of more than 100 meters. The asphalt is being pushed upwards, cracks are forming on the street, just like during an earthquake. The resulting damages which were apparently caused by material fatigue could entail a traffic chaos which may last more than a few weeks.
The police blocks off the central crossing in the district of Altona immediately on Monday. The Holstenstraße between Holstenplatz and Thadenstraße as well as the Max-Brauer-Allee between Stresemannstraße and Eggerstedtstraße are affected by this. In these sections, the roads are blocked off in both directions – with one exception: It is possible to take the Max-Brauer-Allee from the train station Altona up to the Holstenstraße and then make a right turn. Nevertheless, this means that one of the main arteries in the west of Hamburg is practically blocked.
This blocking has a severe effect on the commuter traffic: The flow of traffic on the alternative routes along Stresemannstraße and Königsstraße already starts to stagnate as early as 7am. The same scenario reoccurs in the evening, when the traffic up to the Kieler Straße and the Bahrenfelder Chaussee comes to a halt again.
Passengers in local traffic are caught off guard by the sudden blockage
Local traffic is also severely affected by the situation: The Hamburger Hochbahn AG reports restrictions for the lines 20, 25, 37, 111, 112, 183 and 283. Buses are running irregularly and are partly rerouted. Four hours after the incident on Monday, the situation is still chaotic as passengers report. „I was standing at the bus station with many other people and the arrival times on the passenger information display were wildly jumping back and forth. First, the bus was supposed to arrive in five minutes, then it was three minutes, then eight minutes and there were no further announcements” one of the passengers says. "I thought these information displays were supposed to provide passengers with information." After 45 minutes she gave up and tried to find a different way to get to the city centre.
On Monday afternoon, the Hamburger Hochbahn AG reported that the bus lines 20, 25, 183 and 283 will probably still be affected until May 26th. They already advised passengers in the morning to switch to rapid transit trains if possible.
On Monday, Hamburg Wasser called in a construction company. Since the asphalt was pushed upwards, drillings have to be carried out to determine the level of compression of the road bed. The police reported that it could take up to two weeks to repair the damages but that they are not able to give an exact prediction at the moment. “We are currently trying to determine the extent of the damages caused“ says Sabrina Schmalz, spokesperson for Hamburg Wasser.
Burst main line is already 40 years old
The burst pipe is a main line with a diameter of 60 cm. This line was built in 1977 and therefore matches the average age of the lines within the Hamburger water supply network which has an overall length of 5300 km. "The water supply for the residents in the area is not affected by the burst pipe“ Hamburg Wasser assures us. No households are connected to the big distribution lines.
It’s assumed that material fatigue in connection with the high pressure on the crossing caused by traffic was the reason for the bursting of the pipe. The Max-Brauer-Allee is used by 30,000 vehicles every day, more than 1700 of those are heavy goods-vehicles. Accidents with construction equipment as well as the change between frosty weather and thaw can lead to pipe bursts as well.
On average, the supply lines in Hamburg are 40 years old, some are even considerably older than 50 years. However, the number of burst pipe incidents was reduced by almost 50% in the last 20 years. Recently, 484 incidents were counted in a year, most of them with no impact on traffic. The incident with the most serious consequences in the last few years occurred three years ago, when a large area of the Gärtnerstraße in the district of Eimsbüttel was completely washed out.
According to Hamburg Wasser it is not possible to predict the risk of breakage of a water pipe. Despite the use of metal analyses and static models, the findings on the condition of the pipes are limited. "Due to sanitary reasons, the pipes cannot be inspected from the inside“ Sabrina Schmalz says. The rehabilitation of pipes also interferes with traffic. Therefore, construction measures and their consequences have to be weighed up against each other. Each year, four kilometers of old pipes are replaced.
(Hamburger Abendblatt, May 16th, 2017)