Urban Construction  

 

Archive: The Capital City of Berlin - Documentation

3. Subsoil


A government building is not simply built on sand. Before the building work can be begun and the building cranes approach, the subsoil must be prepared and made ready. First the properties must be cleared, meaning the subsoil debris of cellar remains and foundations, the removal of possible contamination as well as excavating wartime weapons. In addition, the historical traces must be preserved through careful documentation.

Clearing the Building field

Large open areas in the centre of the city are used for the construction of the Parliamentary and Government Quarter. These were formerly densely built up and were all located in the "final battle area around the Reichstag". This required a truly fundamental, thorough-going and far-reaching clearance from contamination of every kind.

The large areas of the building field clearance are:
Moabiter Werder for the apartment buildings of the Federal employees (1), Police and Fire Brigade of the northern Moabiter Werder (2), the former Lehrter Bahnhof, today the Hauptbahnhof (3), Federal Chancellery/Spreebogen (4), Platz der Republik/Forum (5), Paul-Löbe-Haus (Alsenblock) (6), Marie-Elisabeth-Lüders-Haus (Luisenblock-West) (7), Wohnblock Luisenstraße (8), Sculpture Garden and Hafenplatz (9), Jakob-Kaiser-Haus (Dorotheenblöcke) (10), Ministergärten (11), Ministry of Foreign Affairs of the GDR/Schinkelplatz (12), Werderscher Markt (13), Friedrichswerder-West (14), the Palast der Republik (Humboldt Forum) (15) and Petriplatz (16).

Dismantling the Palast der Republik (view from the Liebknechtbrücke)

2009 - The area surrounding the former Stadtschloss without the Palast der Republik; Future impression: treibhaus landschaftsarchitektur
2009 - The area surrounding the former Stadtschloss without the Palast der Republik
Future impression: treibhaus landschaftsarchitektur

The clearing of the building field included about 2 million t of soil excavation and demolition waste altogether as well as 30 t of weapons from the Second World War, some even from the time of the First World War. Some of the areas resembled a crater landscape after the clearance. They were refilled with approximately 680,000 t of pure coarse sand, as far as required. In the four largest areas of the building-area clearance, the following masses of soil excavation and demolition waste were removed: Moabiter Werder 480,000 t - Ministergärten 340,000 t - Alsenblock 250,000 t - Luisenblock West 190,000 t. That makes a total of almost 1.3 million t of excavated material in these areas alone! But not much of this was noticed in the city - thanks to building logistics orientated towards sparing the city. The transport of demolition waste and soil excavation took place via the Spree River, as did the transport of refilling sand. Five loading points were constructed for these transports and they disappeared again completely after the clearing of the building field was completed.
1998 - Clearing of the Ministergärten
1998 - Clearing of the Ministergärten

2007 Freilegungen im Bereich der 'Entwicklungsmaßnahme Hauptstadt Berlin – Parlaments- und Regierungsviertel'; Source: Senatsverwaltung für Stadtentwicklung Berlin II B / DSK, März 2007
2007 Clearance of areas designated in the "Development Measure for the Capital City of Berlin – Parliamentary and Government Quarter"
Source: Senatsverwaltung für Stadtentwicklung Berlin II B / DSK, March 2007

From planning to building/construction in numbers

(date: 31 December 2006)
Clearing of the building field:
Excavation material and building rubble:
2 million tons

thereof from the four biggest projects:
  • Moabiter Werder 480,000 tons
  • Ministergärten 340,000 tons
  • Alsenblock 250,000 tons
  • Luisenblock West 190,000 tons
other clearing of land: 740,000 tons
additionally:
  • explosive ordnance: 30 tons
  • refilling of cleared surfaces/areas: 680,000 tons sand
 

The Example of Building-Site Logistics

Special building-site logistics were erected on the Kapelleufer on the north side of the Spree River for the construction of the Federal Chancellery, longdistance-rail and street tunnel and the Hauptbahnhof. The "Spreebogen Consortium for Building-Site Logistics" (KBS), established and installed by the "Project Association for Traffic Affairs in Central Berlin, Ltd. - PVZB," received the task of transporting the complete mass of 5.8 million t of soil excavation and 1.5 million t of concrete by waterway (80 percent) and by rail (20 percent) without using the streets. This task could only be managed with a special infrastructure detached from the city traffic. This included not only three kilometres of road, a tunnel under Invalidenstraße and a temporary bridge over the Spandauer Schifffahrtskanal as well as another temporary bridge 90 metres long over the Spree, but also a specially-built cement-making machine with a top capacity of 83,000 cubic metres per month. The ship traffic on the Spree was coordinated by a specially installed central office for ships.


 

Exploring the subsoil

Extensive investigations preceded the clearing of the building field: these included soil reports, investigations of contamination and appraisals of asbuilt maps to determine the state of conductions/pipelines. The geophysical examination makes it possible to view materials buried underground. The area to be cleared is first finely "combed" with geomagnetic and geo-electronic measuring tools. The first result of this comprehensive work is a map which helps to register the approximate location of the soil anomalies found underground (remains of foundations, pipelines/conductions, bomb splinters).

In some cases archaeological investigations were also part of the clearing of the building field. They are based upon previous researches in the files and the study of historical plans and maps. If a building area is of archaeological interest, excavation teams of the Provincial Monument Bureau (LDA) accompany the clearance of the property. Their previous knowledge of the underground area does not only serve the localisation of archaeologically relevant places, but also determine the extent and depth of the clearance. This is why they are an important mosaic-stone in the planning and execution of the entire clearing of the building field in particular and also for the search of historical traces. Clearance and archaeological excavations are often carried out simultaneously in order to save time.


Petriplatz, Berlin Mitte - geophysical examination; Map: Büro für Geophysik Lorenz
Petriplatz, Berlin Mitte - geophysical examination
Map: Büro für Geophysik Lorenz
 

Traces of Old Berlin

The constructional underground of the city is full of surprises. Witnesses are stored here which reveal important insights about the city. The clearance of properties for new construction offers a unique opportunity to delve into the depths of history, sift through and secure hidden traces of urban life. The archaeological excavations form an essential component of the development measure.

Locations of archaeological excavations in the area of construction measures:
  1. Berliner Schloss (continuation of the investigation excavations prior to the new construction);

  2. Bauakademie (in connection with the demolition of the Ministry of Foreign Affairs);

  3. Commandant's Office (before its reconstruction);

  4. Münze (in preparation of the new construction for the Ministry of Foreign Affairs);

  5. Reichsbank (as part of the clearing of the building field on Friedrichswerder);

  6. Petriplatz (for the preparation of the urban-constructional restructuring);

  7. Ministergärten (parallel to the clearing of the building field for occupation by the Provincial Representatives and the construction of the monument for the murdered Jews of Europe).

The archaeological investigation in the area of Petriplatz is referred to as an example for the knowledge content and historical value of an excavation.


2007 - Remains of walls from the Stadtschloss; Photo: GWAC GmbH
2007 - Remains of walls from the Stadtschloss
Photo: GWAC GmbH

Plan Schlossplatz Berlin Mitte; editor: Senatsverwaltung für Stadtentwicklung, Vermessungswesen; Büro für Geophysik B. Lorenz; Landesdenkmalamt Berlin
Plan Schlossplatz Berlin Mitte
Editor: Senatsverwaltung für Stadtentwicklung, Vermessungswesen; Büro für Geophysik B. Lorenz; Landesdenkmalamt Berlin
 

Excavations at Petriplatz

The excavations at Petrikirchplatz on Gertraudenstraße stood under the sign that one had to reckon here with extremely interesting findings and extensive excavations were to be undertaken. The construction traces of the former Petri Church, the accompanying cemetery and the former City Hall of Cölln are of outstanding importance for the urban history of Berlin. The excavation is among the most interesting urban archaeological projects of recent years. It was begun in March 2007. The archaeological excavations carried out in connection with the clearing of the building field led to repeated interruptions of the clearance measures because of their importance. The desire to present the archaeological findings on location permanently is presently being investigated for its feasibility.

The rediscovery of the cellar of the Latin School mentioned in the Cölln city records of 1442 is of outstanding importance. It is the oldest known school in Berlin. In the refilling of the school cellar are found tiled stoves with picture tiles and inscriptions, pieces of painted and inscribed plates and, so far, nearly 500 glass seals of bottles.

On the other side of the school walls are the graves of the Petri Church, which must have already existed in 1237, at the time of the first mention of a Pastor Symeon, at the Petri Church. In 1717 the cemetery was abandoned after 500 years. This means that over a hundred generations of Cölln residents were buried at this location, including influential and famous citizens of the city.

At least three Petri Church buildings overlap in the centre of the future Petriplatz. After the catastrophic fire of 1730, Johann Friedrich Grael began with a new construction, the tower of which collapsed in 1734. The succeeding new church construction was also destroyed by fire in 1809. The final Petri Church built between 1846 and 1853 possessed the city's highest church tower, at 111 metres. The neo-gothic construction suffered severe damage during the Second World War.


2007 - Excavations at Petriplatz; Photo: Landesdenkmalamt Berlin / Claudia Melisch
2007 - Excavations at Petriplatz
Photo: Landesdenkmalamt Berlin / Claudia Melisch