Sustainable Water Management - Sustainable Practices in Geoenvironmental Engineering - page 74

About 0.2% to 0.3%
lakes, rivers, ponds,
other receiving waters

is includes aquifers
and soil porewater
above and below the
water table

Groundwater represents
at least 90% of the world's
readily available
freshwater
(Boswinkel, 2000;
WRI et al., 1998)

About 29.5%
groundwater

is small fraction
(~5%) of snow and
ice is available
freshwater

3.5 × 10 16 m 3 freshwater
representing about 2.5%
of total global water ( saline
and nonsaline water )

About 95% of the snow
and ice ( freshwater) is
in the form of glaciers
and ice caps located in
the Arctic and Antarctic

About 70%
snow and ice

FIGURE 3.1
Sketch of distribution of global freshwater.

3.1.1.1 Water Availability and Quality

Water availability and water quality are central issues in survivability of living species—
humans, animals, plants, etc. Lack of water and unacceptable water quality are signiicant
threats to survivability. Water availability or the lack thereof is a topic that is well covered
in textbooks devoted to such a subject. The problem of threats to the quality of water in the
geoenvironment constitutes the central focus of discussions in this topic. It has been said
previously, in Chapter 2, that soil contamination does not only mean contamination of the
soil solids themselves, but also contamination of the porewater, with possible extension to
groundwater and the aquifers through transport of contaminants in the subsoil. Chemical
stressors producing point source and non-point source contaminants (to be discussed in
the succeeding chapters) will contaminate not only soils but the receiving waters. The
importance in protection of available freshwater, and especially groundwater, is demon-
strated in Figure 3.1, which highlights the degree of utilization of this resource by the
world's population.

3.2 Uses of Water and Its Importance
Safe and adequate amounts of water are essential. The irst Dublin-Rio principle has
emphasized the need for sustainable water resource practices. It states that “fresh water is
a inite and vulnerable resource, essential to sustain life , development , and the environment ”