Rain
is the prime source of all water. A part of the rain water sinks into the
ground to form ground water. Part of it evaporates back into the atmosphere and
some runs off to form streams and rivers which flow ultimately into the sea. Some
of the water in the soil is taken up by the leaves. These events are spoken of
as water cycle.
is the prime source of all water. A part of the rain water sinks into the
ground to form ground water. Part of it evaporates back into the atmosphere and
some runs off to form streams and rivers which flow ultimately into the sea. Some
of the water in the soil is taken up by the leaves. These events are spoken of
as water cycle.
Rain
water is the purest water in nature. Physically it is clear, bright and
sparkling chemically, it is very soft water containing only traces of dissolved
solids (0.0005 percent). Being soft, it has no corrosive action on lead pipes.
Bacteriological, rain water from clean districts is free from pathogenic
agents.
water is the purest water in nature. Physically it is clear, bright and
sparkling chemically, it is very soft water containing only traces of dissolved
solids (0.0005 percent). Being soft, it has no corrosive action on lead pipes.
Bacteriological, rain water from clean districts is free from pathogenic
agents.
Impurities: – Rain water tends to become impure as
it passes through the atmosphere such as dust, soot and microorganisms and
gases such as carbon dioxide, nitrogen, oxygen and ammonia. Gaseous sulphur and
nitrogen oxides are emitted from power plants that use fossil fuels. These
gases react with atmospheric water forming dilute solution of sulphuric and
nitric acid. The precipitation of these acids (acid rain) has begun to have
serious impacts on surface water quality and plants etc.
it passes through the atmosphere such as dust, soot and microorganisms and
gases such as carbon dioxide, nitrogen, oxygen and ammonia. Gaseous sulphur and
nitrogen oxides are emitted from power plants that use fossil fuels. These
gases react with atmospheric water forming dilute solution of sulphuric and
nitric acid. The precipitation of these acids (acid rain) has begun to have
serious impacts on surface water quality and plants etc.
Surface water: – Surface water originates from rain water;
it is main source of water supply in many areas. Surface water is prone to
contamination from human and animal sources. As such it is never safe for human
consumption, unless subjected to sanitary protection and purification before
use.
it is main source of water supply in many areas. Surface water is prone to
contamination from human and animal sources. As such it is never safe for human
consumption, unless subjected to sanitary protection and purification before
use.
River: River water is turbid during raining season; it may be clear in other
seasons. Clarity of water is no guarantee that the river water is safe for
drinking river water contains dissolved and suspended impurities of all kinds.
seasons. Clarity of water is no guarantee that the river water is safe for
drinking river water contains dissolved and suspended impurities of all kinds.
The impurities of river water are derived from surface washings
sewage and sullage water, industrial and trade wastes, and drainage from
agricultural areas. The customs and habits of the people like bathing, animal
washing and disposal of the dead, all add to the pollution of water. Self
purification certain amount of self purification does occur in river water by
natural forces of purification such as dilution, sedimentation aeration,
oxidation, sunlight, plant and animal life but these agencies are not
sufficient to render the water potable. River water needs purification before
it can be used for dinking purposes. Purification or treatment of surface water
supply: there are two principal methods of purifying or treating water supply
derived from surface sources e.g. Streams or rivers. These methods are natural
purification otherwise know as self purification and artificial purification
which involves the subjection of the water to various treatment processes.
sewage and sullage water, industrial and trade wastes, and drainage from
agricultural areas. The customs and habits of the people like bathing, animal
washing and disposal of the dead, all add to the pollution of water. Self
purification certain amount of self purification does occur in river water by
natural forces of purification such as dilution, sedimentation aeration,
oxidation, sunlight, plant and animal life but these agencies are not
sufficient to render the water potable. River water needs purification before
it can be used for dinking purposes. Purification or treatment of surface water
supply: there are two principal methods of purifying or treating water supply
derived from surface sources e.g. Streams or rivers. These methods are natural
purification otherwise know as self purification and artificial purification
which involves the subjection of the water to various treatment processes.
It
is important to note that the main purpose of purifying water is to achieve the
following objectives.
is important to note that the main purpose of purifying water is to achieve the
following objectives.
1.
To
remove harmful impurities in raw water and bring its quality to acceptable
standards.
To
remove harmful impurities in raw water and bring its quality to acceptable
standards.
2.
To
make the water potable i.e safe for human consumption and other domestics
purposes.
To
make the water potable i.e safe for human consumption and other domestics
purposes.
3.
To
free the water from pathogenic organisms
To
free the water from pathogenic organisms
4.
To
remove objectionable and unpleasant tastes and colours from the water. On
health grounds, it is unsafe to render water absolutely pure. This is so
because human body requires certain minerals and chemicals in minute quantity
to enable it carry out its physiological function well.
To
remove objectionable and unpleasant tastes and colours from the water. On
health grounds, it is unsafe to render water absolutely pure. This is so
because human body requires certain minerals and chemicals in minute quantity
to enable it carry out its physiological function well.
Natural
or self-purification
or self-purification
Self
purification is the process by which oxygen in the water of stream or river is
consume by pollutional load for its decomposition and stabilization and at the
same time replenished by the atmosphere. In other words the ability of a stream
to assimilate wastes discharged into it and quite restoration of its quality is
self purification.
purification is the process by which oxygen in the water of stream or river is
consume by pollutional load for its decomposition and stabilization and at the
same time replenished by the atmosphere. In other words the ability of a stream
to assimilate wastes discharged into it and quite restoration of its quality is
self purification.
