See how far that house is tilting? This is due to the high water table near the canals. Any building
in Amsterdam has water table problems, but the closer you are to a canal, the worse the problem becomes.
The water table is a constant engineering challenge in Amsterdam, impacting not only
building construction, but also impacting the metro subway construction. For example,
to minimize impacts on surface buildings, many of the Amsterdam metro lines are
built directly underneath canals.
Quick Water Table Info: The water table under Amsterdam is high. If you were to dig a hole anywhere
in Amsterdam, it will fill up with water pretty quickly. The soil itself is simply too soft to support a
building, let alone transportation infrastructure. Even the first small, wooden houses built along the
Amstel kept sinking into the boggy ground.
In Amsterdam, you need to dig down 400 meters to hit rock. On the way down, there are
alternating layers of clay, peat and sand. As any engineer will tell you, clay and peat
cannot support the weight of a building.
The Amsterdam solution? Wooden piles (beams of timber driven into the earth). The foundations of most
buildings in Amsterdam are supported on piles 12 meters deep that are anchored in the first
layer of sand. The piles of larger buildings are even deeper, reaching to the second layer
of sand at 20 meters or to the third at 50 meters deep. Altogether, there are more than
a million piles under Amsterdam.
Click here to
read the complete article on the "medium.com" website. This is a good article about the construction difficulties that Amsterdam has faced, describes the history of the Amsterdam Metro System, etc.