Drilling of boreholes
Boreholes are drilled to obtain drinking water from the deeper
layers of earth, where water is cleaner and more qualitative,
protected from bacteriological contamination. The depths
used most often range from 30 m to 120 m. The depth for the
particular borehole is selected after considering the following:
the depth of good drinking water that may be obtained at the
specific place of Latvia; the amount of water needed for the
consumer; the option most advantageous economically for the
client. Water obtained from deeper boreholes is more qualitative
in comparison to water yielded from the upper or Quaternary
layers of the ground, although such way to obtain water from
sand or gravel by a filtration borehole or spice filter is an option
used most often. It is economically reasonable to install a sieve
filter or spice filter in the well, if the needed amount of water is
not large and it is used only for a household or periodically, for
example, during the summer season. It is possible to install spice
filter only in the areas, where sandy ground and uncontaminated
environment is available.
Up to 150 m deep borehole is drilled for the needs of an artesian
well, where special thick-wall plastic, corrosion resistant or
ordinary steel pipes are inserted. In separate cases, water can
be obtained also from deeper boreholes. The artesian water is
enclosed among water impermeable layers and found in deeper
layers of the ground. Depending on the kind of layers down
to which the well is drilled, the water is of different chemical
content. Sometimes, the amount of mineral substances exceeds
the norms set for good drinking water. For example, water
pumped out from dolomite layers may display an increased
hardness, from sandstone – an increased content of iron. If the
concentration or presence of these compounds make hard to use
the water for a household, special filters, iron removers or water
softeners are installed.
The advantages of an artesian well are cleaner water and its
constant flow, it can satisfy needs for comparatively large water
consumption, as well as the well will serve longer and the water
resources do not come to end.
An artesian well can be finished in 3 to 10 days depending on
its depth, construction and content of soils. The costs for the
drilling of an artesian well depend on its depth, the selected
materials and the amount of water needed for the client. The
company provides the necessary documents (the licence, the
passport of a well) and the bacterial and chemical analyses of
the obtained water.
The company has several drilling machines in its possession.