Waste Water Story

What is Waste Water?

It is a type of water which is contaminated by human use like washing of clothes, industrial discharge, commercial as well as agricultural activities. As all these contaminating sources disturb the quality of water which leads to contamination of water. Contamination also depends on various sources or products such as domestic wastewater, municipal wastewater i.e sewage and industrial waste of chimanies. Wastewater mainly contains physical, chemical and biological pollutants. We can purify this contaminated water by various methods, there are so many power plants which do purification processes.


Effects of Contaminant on Quality of Water:

There are various harmful result noticed due to contamination of water, some of them are listed below:

  1. Loss of Aquatic Organisms: Aquatic organisms are harmed due to contaminated water. As discharges and runoff of harmful contaminants like pesticides  into waterways can be lethal to aquatic life, causing death of fishes, prawns, etc.

  2. Loss of Local Invertebrate Species: As these small invertebrates are food for fishes and other aquatic organisms. Death of these invertebrates lead to starvation for those aquatic organisms who are dependent on them for food and they start migrating to other water bodies exposing them to greater risk and stress.

  3. Decrease in Biochemical Oxygen Demand(BOD): Due to waste or harmful contaminants they use up natural oxygen present in the water body. Excess nutrients can also lead to algal blooms and oxygen is used up when the algae die and decompose. Decrease in available oxygen causes difficulty in breathing to aquatic organisms.

  4. Contaminant increases turbidity and decreases water clarity of water thus making water murky. So this aquatic organism is not able to find their prey and detect predators.

  5. Contaminated water causes internal damage to aquatic organisms as they reduce the reproductive ability of aquatic organisms, decrease in immunity, causes disorder in the central nervous system, etc.


Types of Water Pollution Depending on Different Source:

  1. Surface Water Pollution: This type of pollution includes pollution in rivers, lakes and oceans. Here water sources are contaminated by various means like industrial waste, release of sewage waste, etc.

  2. Marine Pollution: one of the common ways by which contaminants enter the sea are rivers. Here directly discharging sewage and industrial waste into the ocean causes pollution into oceans.  Plastic debris can absorb toxic chemicals from ocean pollution, potentially poisoning any creature that eats it.

  3. Groundwater Pollution: Use of pesticides and insecticides causes contamination of groundwater. Groundwater pollution is directly connected to soil pollution.


Wastewater Management:

Wastewater treatment is a several step process and by going through these process we purify contaminant water:


Steps performed during purification of contaminated water:

  • Wastewater Collection

  • Screening

  • Primary Treatment

  • Secondary Treatment

  • Final Treatment


Wastewater Collection:

Very first step in the purification process is collection of water in a storing tank which further goes through various filtration steps.


Screening:

This is the very first step of water treatment. In this process large objects are removed from wastewater and then moved into the grit and sand removal tank, where they are further treated.


Primary Treatment:

After going through screening water is taken to primary treatment where all organic waste present in water is removed and this process is done by pouring the wastewater into a big tank where solid matthew style down at the base.


The settled solids, after primary treatment, are called the sludge. This sludge is decomposed by bacteria and the gas emitted by this decomposition  is known as biogas, which can be used as a fuel or can be used to generate electricity.


Secondary Treatment:

After primary treatment water is passed to an aeration tank where air is tapped into water to increase the growth of aerobic bacteria in the water. These bacteria break down small particles of sludge that are not broken during primary treatment. These broken slugs are known as activated sludge. These activated sludge contain air in them.


Final Treatment:

This activated sludge is passed through a bed of sand drying machine where the sludge is dried up  and from the water is filtered out. This water is filtered and then released into the river.


How to Control Water Pollution:

There are several way to prevent water pollution, some of them are below:

  1. Industrial Wastewater Treatment:

As industrial waste is discharged into water bodies which causes contamination of water.

So by using pre-treatment plants for reducing harmful chemicals present in industrial waste, this process will decrease contamination of water.

  1. Agriculture Wastewater Treatment:

By reducing use of pesticides and weedicides we can reduce underground water pollution. As these chemicals contaminantes water which causes various health related issues.

  1. Municipal Wastewater Treatment:

Instead of discharging sewage waste directly into water bodies treat it in separate sewage treatment plants to reduce water pollution.

FAQ (Frequently Asked Questions)

1. Discuss Harmful Effects of Contaminants on Quality of Water?

Ans: These harmful contaminants reduce quality of water in various ways:

  1. Loss of Aquatic Organisms: Aquatic organisms are harmed due to contaminated water. As discharges and runoff of harmful contaminants like pesticides  into waterways can be lethal to aquatic life, causing death of fishes, prawns, etc.

  2. Loss of Local Invertebrate Species: As these small invertebrates are food for fishes and other aquatic organisms. Death of these invertebrates lead to starvation for those aquatic organisms who are dependent on them for food and they start migrating to other water bodies exposing them to greater risk and stress.

  3. Decrease in Biochemical Oxygen Demand(BOD): Due to waste or harmful contaminants they use up natural oxygen present in the water body. Excess nutrients can also lead to algal blooms and oxygen is used up when the algae die and decompose. Decrease in available oxygen causes difficulty in breathing to aquatic organisms.

  4. Contaminant increases turbidity and decreases water clarity of water thus making water murky. So this aquatic organism is not able to find their prey and detect predators.

  5. Contaminated water causes internal damage to aquatic organisms as they reduce the reproductive ability of aquatic organisms, decrease in immunity, causes disorder in the central nervous system, etc.

2. Explain Various Steps Should be Taken for Treatment of Polluted Water.

Ans: Some major steps towards treatment of wastewater are: 

  1. Industrial Wastewater Treatment:

As industrial waste is discharged into water bodies which causes contamination of water. 

So by using pre-treatment plants for reducing harmful chemicals present in industrial waste, this process will decrease contamination of water.

  1. Agriculture Wastewater Treatment: 

By reducing use of pesticides and weedicides we can reduce underground water pollution. As these chemicals contaminantes water which causes various health related issues.

  1. Municipal Wastewater Treatment:

Instead of discharging sewage waste directly into water bodies treat it in separate sewage treatment plants to reduce water pollution.