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We classify
lakes, rivers, reservoirs and ponds, for example, as
surface water. These bodies receive water directly from
precipitation and from surface run-off. They also derive
a portion of their supplies from underground springs
connected with ground water sources.
While surface water, as a rule, has the advantage of
lower mineral content, there are certain disadvantages
to be considered:
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The presence of much contaminated matter making
water unfit for human consumption until properly
treated.
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Industrial and municipal pollution of many
supplies.
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Surface run-off bringing mud and decayed
vegetation into the water.
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Possibility of animal and human wastes in the
water.
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In many cases good environments for algae and
bacteria.
Regardless of the mineral and organic make-up of a
water source, both deep wells and large lakes make
available water that is more or less consistent quality
from season to season. In contrast, many small bodies of
water, shallow wells and springs often reflect seasonal
and even daily variations in their mineral content.
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