Sources of Water (Surface and Subsurface):
- Surface
Water: This is water that is found on the Earth's surface in streams,
rivers, lakes, ponds, and wetlands. It also includes rainwater runoff and
snow melt.
- Subsurface
Water (Groundwater): This is water located beneath the Earth's
surface, stored in the pore spaces of soil and rocks, or in underground aquifers.
It's often accessed through wells and springs.
Sources of Water Pollution:
- Industrial
Waste: Factories often discharge waste into water bodies, which can
contain harmful pollutants like heavy metals, chemicals, and heated water.
- Agricultural
Runoff: This can contain chemical fertilizers and pesticides, or
organic pollutants like animal manure, which can lead to nutrient
pollution and eutrophication.
- Sewage
and Wastewater: Untreated or inadequately treated sewage can carry a
wide variety of harmful microorganisms and other pollutants.
- Oil
Spills: These can cause significant harm to aquatic ecosystems.
- Landfills:
Leachate from landfills can contaminate both surface water and
groundwater.
Effects on Environment and Lives:
- Ecological
Impacts: Water pollution can harm or kill aquatic organisms, reduce
biodiversity, and disrupt food chains.
- Health
Impacts: Polluted water can cause a range of health problems in
humans, including diarrhea, skin irritation, respiratory problems, and
even cancer.
Preventive Measures:
- Improved
Waste Treatment: This includes proper treatment of industrial and
municipal waste before it's discharged into water bodies.
- Regulation
and Enforcement: Governments can set and enforce standards for water
pollution, and penalize violators.
- Education
and Awareness: Public awareness campaigns can help people understand
the importance of preventing water pollution and how to do so.
- Sustainable
Practices: In agriculture, this can involve using organic farming
methods or precision farming to reduce runoff.
BIS Water Quality Standards:
The Bureau of Indian Standards (BIS) has set quality
standards for drinking water in India, known as IS 10500. These standards
specify acceptable levels for various physical, chemical, and bacteriological
parameters in drinking water, including turbidity, pH, total dissolved solids,
heavy metals, and pathogenic bacteria.
Flow Diagram of Water Treatment Plant:
- Coagulation/Flocculation:
Chemicals with a positive charge are added to the water. These chemicals
neutralize the negative charge of dirt and other dissolved particles in
the water, causing them to bind together or coagulate. The larger
particles are called flocs.
- Sedimentation:
Flocs are heavy, so they settle to the bottom of the water supply, due to
gravity.
- Filtration:
The clear water on top then passes through different layers of sand,
gravel, and charcoal to remove even smaller particles.
- Disinfection:
Finally, a disinfectant (like chlorine or ozone) is added to kill any
remaining parasites, bacteria, and viruses.
Water Conservation:
This involves using water resources in a sustainable way to
reduce waste and protect future availability. Measures can include fixing
leaks, installing water-efficient appliances, using rainwater harvesting or greywater
systems, and implementing efficient irrigation methods in agriculture. It also
involves protecting natural water resources from pollution and overuse.