Inside the Earth, groundwater reaches a maximum depth and this place is known as the water table. In this place the water pressure is equivalent to atmospheric pressure. Likewise, the water table is the specific distance between the groundwater level and the surface.
The detection of the phreatic level is normally carried out through a probe, which detects the presence of water in the subsoil. The geological and climatic characteristics of a place are what determine the depth of the water table.
Groundwater
The water found at the groundwater level is known as groundwater. In principle, it is not a suitable water for human consumption, but it is usable for the irrigation of crops, for urban cleaning and the sewage system. In this sense, some cities have underground groundwater networks. It is an alternative water resource that replaces traditional sources and springs.
The water table in construction
In a land where a building or hydraulic work is to be built, it is essential to know the groundwater water table. These types of studies are called geotechnics and geologists are the professionals who are dedicated to it.
The study of a soil is decisive to calculate its resistance capacity. This type of study focuses on the different layers or strata of a terrain. As is logical, the layer or phreatic level is of vital importance to make an adequate decision in relation to the construction of a building. Thus, the water table must always be below the first foundation level, otherwise the building could be damaged over time.
The information obtained makes it possible to establish the maximum height level of a building. The person in charge of this type of analysis is a soil engineer.
The physical and mechanical composition of a soil and its deeper layers determine the type of foundation that can be built.
Phases in the study of soils
The first step is to carry out field work and at this stage drilling is done to extract soil samples. In the next section, the samples obtained are taken to a laboratory to analyze the different layers of the terrain. According to field and laboratory work, the necessary recommendations for the foundation can already be made.
Photos: Fotolia - Pichaitun / Francesco Scatena
