Depth to the Water Table 2009
The depth to the water table classes “2 to 4 meters,” “4 to 10 meters,” “10 to 20 meters” and “20 to 40 meters” each account for approx. 20 % of the surface area of Berlin. Groundwater-proximate areas with depths to groundwater < 2 meters make up approx. 12 % of the area. Very great depths to groundwater > 40 meters occur only occasionally at morphological high sites, on approx. 1 % of the area of Berlin.
In those areas in which, as described above in the chapter on Methodology, the expanse of the covered quaternary main aquifer under marly till is not coherent, but only isolated, no depth to groundwater is shown. Nevertheless, near-surface groundwater can occur there in such quantities that it can even supply wetlands with sufficient water for the biocenoses present there (e.g. at the upper Tegel Creek valley at Lübars).
In Brandenburg, the depths to groundwater are generally very slight to the southeast and to the northwest of the city within the glacial spillway; elsewhere, in the area of the plateaus, they are in some places very great. In the northeast, they are at more than 40 metres over a broad area within the confined areas of the Barnim.
Within the glacial spillway, depths to groundwater are generally in the range of 2 to 4 meters below the surface. Groundwater-proximate areas with less than 2 meters’ distance between the groundwater and the top edge of the terrain are generally found in the neighbourhood of a number of surface waters. Large areas with depths to groundwater of between 1 and 2 meters are also found in the southern villages of the Borough of Treptow-Köpenick (north and south of Langer See [“long lake”]) as well as in the Spandau Forest at Heiligensee east of the Havel, and also both to the north and to the south of Rummelsburg Bay.
Greater depths to groundwater ( > 4 meters) have either morphological causes (e.g. the dunes in the Tegel Forest, to the east of Müggel Lake, or in the Rehberge [“deer hills”]), or they are located in the intake areas of waterworks wells (e.g. Spandau, Tegel, Friedrichshagen, Johannisthal), caused by the present lowering. In the glacial spillway, small areas can also be found with increased depths to groundwater, where confined groundwater conditions occur. Here, the groundwater depths are formed by the lower edges of the Vistula Moraine via the main aquifer.
The depths to groundwater generally increase strongly in the plateau areas. Here, they are for the most part above 10 meters. The southern edge of the Barnim Plateau stands out particularly prominently. In the eastern area of the Barnim Plateau, depths to groundwater of less than 10 meters appear occasionally (e.g. in the area around Malchow Lake or in the headwaters of the Wuhle). Otherwise however, depths to groundwater of above 20 meters, some even in excess of 30-40 meters, predominate here. The northern area of the Barnim Plateau – cut by the valley of the Panke, with the very slight depths to the groundwater of the surface-proximate Aquifer 1 – is characterized by very great depths to groundwater of in some cases more than 50 meters. The ground moraine reaches a very great thickness here. Below the moraine formations (in places, the Vistula Moraine is directly on top of the Saale Ground Moraine), Aquifer 4 is in some cases even immediately present here. In the northwest, by contrast (Frohnau), the groundwater depths are mostly in the range of 20 to 30 meters, and, in the western areas, such as Bieselheide, often even less than 20 meters, where they are unconfined.
In the Grunewald Forest, as well as generally west of the Havel in Kladow and Gatow, there are extensive depths to groundwater of more than 20 meters. Here, the conditions are predominantly unconfined within the surface plateau sands; the high figures are caused by morphological elevations (the Teufelsberg [“devil’s hill”], the Schäferberg [“shepherd’s hill”], the Havel Hills at the Grunewald Tower), and also in the Müggel Hills.
The western area of the Teltow Plateau between the Grunewald chain of lakes and the Teltow Canal is characterized by strongly varied depths to groundwater of between 5 and 30 meters. There are also differing regional conditions with respect to the confinement of the groundwater here. To the southeast of the Teltow Canal however, depths to groundwater are for the most part greater than 20 meters, with confined groundwater. This area is again subdivided by the valley of the Rudow Stream. To the east, in Bohnsdorf, there are once again depths to groundwater greater than 20 meters.
Compared with the depths to groundwater calculated in May 2002, considerably greater depths to groundwater are to be found only in the confined areas of the Barnim and Teltow Plateaus. These are areas which in May 2002 had been labeled as “unconfined” due to changed ground-water levels, and thus had a considerably higher potentiometric surface.
Considerably slighter depths to groundwater are, however, predominant in the unconfined areas, especially on the edges of the confined areas. This effect is achieved by the current practice of separate calculation of the groundwater surface in confined and unconfined areas (see above). This ensures that the calculation is not influenced by factors from outside the confined areas. The edges of the Barnim Plateau, e.g. east of the Wuhle or west of the Panke Valley, also show this effect very clearly.
In comparison with the last edition of the depth to groundwater map with the groundwater level values of May 2006, deviations arise primarily where improved elevation models could now be applied. Otherwise, only insignificant deviations can generally be ascertained, which generally do not exceed one meter. There are however also areas in which the depths to groundwater have decreased significantly. These involve mostly inner-city areas in which the groundwater is exposed to other local or temporary effects, in addition to those caused by climatic influences – such as construction excavations. In the unconfined areas of the glacial spillway, the depths to groundwater have generally remained at a relatively constant level, when comparing them over the course of three years.