GEO Brasil - UNEP

Therefore, there is one legislation missing, one that
considers the specific aspects of occurrence, uses and
conservation of underground waters in each of the UGRHI
– Unities of Management of Integrated Water Resources.
It is also missing specific legislation that establishes the
principles to be observed for the impounding of rain
waters, and above all, of reuse of rain waters or waters
treated and injected into the underground of each UGRHI,
for example.
However, it is already clear that all the water basins – physical
unities of planning – cannot be ruled by only one legislation
that, by nature, cannot cope with the complexity of each
separate system. Thus, each basin should apply laws in
accordance with their regional peculiarities, according to
Law 9433, encompassing all their different possible sources
of water supply and the different functions – production,
filter, transportation, stocking, regulation, marine interface
control, for example – that could be performed by aquifers
from each basin.
Words that were previously remote have been incorporated
in the daily vocabulary of the decision maker, legislator and
citizen in general. These words include impounding, use
and conservation of superficial and underground water,
environment quality, water basin, systemic management,
water offer for the lowest cost, more efficient use of each
available drop of water, dumping of domestic sewage treated
in rivers and other superficial water bodies, reuse of water
and privatization of public services of supply. Moreover, the
charging for the use of water – user/polluter payer – tends
to be seen as an instrument of management essential for
the creation of balanced conditions between strengths of
offer (availability) and demand (use). This situation
consequently promotes domestic, industrial or agricultural
use that is even more efficient for every available drop of
water.
However, by persisting in the present form of disorganized
extraction of underground water, the supply of potable water,
in particular, becomes ever more critical. So, the use and
protection of underground water should be included in the
policies of water resources, on the federal level as well as on
the states’ or water basins (Rebouças, 1999).
4.4.4. Standardising
The extraction of underground water for human
consumption, in particular, is duly standardized by the
Brazilian Association of Technical Norms – ABNT
(Associação Brasileira de Normas Técnicas), both on the
project level, as well as in the construction of wells. Thus,
the well project is an object of Technical Norm – NBR nº
12.212/92 that substituted NB 588/77 and technical norm
NBR nº 1290/90 related to its construction (Rebouças, 1999).
The observation of such technical norms are proportionate
to the minimal expected conditions of a project that should
correspond to geology engineering (construction), hydraulic
(efficiency) and sanitation (protection of the quality of
produced water)criteria, in particular. In this fashion, the
project of underground water impounding through well or
wells system presupposes the knowledge of:
a) NBR 12211 – Conception studies of public systems of
water supply – Procedure;
b) The outflow intended for the system;
c) The water study containing the basic geophysical and
geological information from the aquifers, hydraulic
characteristics and water quality; in areas where there
is not enough hydrologic knowledge, a preliminary
technical report should be elaborated with the available
data;
d) Evaluation of the system risk;
e) Estimate of the number of wells constituting the
system;
f) Topographic plant on an adequate scale, with location
and register of projects and existing wells, and register
of the levels of present draining and piezometric levels;
g) The water basin plant, in reduced scale, with location
and register of existing wells;
h) Register of the maximum level of floods in the area of
the system.
Thus, the well or the wells of a system of underground
water extraction should be projected and constructed with
equipment and compatible methods with the local geologic
conditions. They should be covered and receive filters that
guarantee the acquisition of hydraulic efficiency adequate
to the production of the project flow. Finally, they should
guarantee the sanitation protection that is crucial for the
quality of the water extracted.
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