What you need to know about thermal pollution

What is Thermal Pollution?

Pollution has many forms. Most of us think of it as air and noise pollution.

We may not realize it, but thermal pollution is emerging as a major area of concern.

Thermal pollution occurs when warm and polluted water from industries is discharged into nearby water bodies. During this process, the temperature of the water body used to discharge the warm water, rises.

The discharged water also contains toxic elements that further damage the aquatic ecosystem.

As the water temperature rises and more toxins are dissolved, the dissolved oxygen (DO) levels reduce.

DO is important for the survival of aquatic species. They become suffocated due to decreasing DO levels in the water bodies. It can lead to loss of life and a reduction in biodiversity.

We need to realize that thermal pollution is real and fast, becoming a global problem.

All the relevant stakeholders need to play an active role in addressing thermal pollution.

The current article provides insights into different aspects of thermal pollution. It highlights the principal causes and dangers of thermal pollution.

The different ways to deal with and reduce thermal pollution are also discussed.

Causes of Thermal Pollution

There are many factors that directly or indirectly contribute to thermal pollution. Some of the most important causes of thermal pollution are as follows:

Manufacturing Plants

Manufacturing and power plants are the most significant contributors to thermal pollution. They are responsible for discharging significant levels of heat into nearby waterbodies.

These manufacturing units and power plants use water from nearby sources as a cooling agent.

Once the water is used for cooling purposes, it becomes hot. The same warm and polluted water is then released to the nearby water bodies, which are usually also the source of water used.

Most of these manufacturing units and power plants discharge water which is at least 10 degrees higher in temperature to the nearby water bodies. This creates a severe imbalance in the local aquatic ecosystem as the species find it difficult to adjust to the sudden hike in water temperature.

Discharge of Industrial Effluents

Industrial effluents are another major culprit and contribute heavily to thermal pollution.

These effluents originate from different sources like institutions, manufacturing units, nuclear units, etc. They discharge a lot of heat and heat-absorbing materials to the water bodies where they are released.

Industrial effluents are discharged by industrial units and can negatively impact the aquatic ecosystem and species.

Domestic Sewages

Domestic sewages are generally released to the nearby water bodies. It is a common practice in many parts of the world. This may seem like a convenient solution for discharging sewage, but it has a drastic impact on the local ecology.

In most cases, the domestic wastewater is released to the water bodies with minimal or no treatment.

Sewage has a higher temperature than the water into which it is being discharged. This is due to the presence of organic waste.

Unregulated release of domestic sewage into nearby water bodies can cause the death of many aquatic species and loss of biodiversity.

Strom Runoff

Storm runoff is another cause of thermal pollution.

During summers, the roads and pavements in urban areas can become very hot. When there is a sudden storm or heavy downpour, the water falling on these roads and pavements can become hot too.

The rainwater runoff absorbs this heat and is discharged into the nearest waterbody. This causes the temperature of the waterbody to increase and contributes to thermal pollution.

Deforestation

Forest cover plays an essential role in maintaining the ecological balance. It helps to reflect and absorb the sun’s rays and heat. It is because of forests only that our water bodies are protected from the sun’s heat.

Deforestation is on the rise and has become a rampant and disturbing global problem.

Deforestation exposes the waterbodies to the sun’s heat directly. This increases water temperature and thus triggers thermal pollution.

Deforestation also causes an increase in the greenhouse effect which contributes to global warming.

Soil Erosion

Most of us may not realize, but soil erosion can contribute to thermal pollution.

Soil erosion leads to higher runoff. This causes more siltation and deposition of sediment in the waterbodies.

Higher accumulation of silt and sediment raises the water levels. It results in a greater surface area of the water body being exposed to sunlight.

As a result, the water temperature rises, and thus thermal pollution takes place.

Natural Factors

Thermal pollution is not only a consequence of human activities and industrialization. Sometimes the forces of nature can also trigger it.

Natural factors can also cause thermal pollution.

There are natural phenomena like geothermal activities and active volcanoes that can lead to an increase in underground water temperature. This can cause the water temperature of underground water bodies to rise sharply.

As the underground waterbody temperature rises, it sets in place thermal pollution.

Dangers of Thermal Pollution

Thermal pollution has emerged as a significant concern globally. It has a severe and long-lasting impact on the aquatic species and the overall balance of the ecosystem.

The critical dangers of thermal pollution are discussed below:

A decrease in Dissolved Oxygen (DO) Levels

Water is heated and becomes warm due to thermal pollution. The waterbody to which the polluted water is discharged from the industries becomes warm. This reduces the DO levels in it. This is because warm water holds lesser oxygen than cold water.

DO is critical to marine ecosystems.

Reduced DO levels can cause the marine flora and fauna to suffocate and this may result in anaerobic conditions.

Warm water is the perfect breeding ground for algae. When algae start accumulating on the surface of a waterbody, it further reduces the DO level.

Increased Toxins

Thermal pollution is marked by the discharge of polluted and warm water from industries to a nearby waterbody.

The release of contaminated water causes a drastic increase in toxin levels.

Discharged water can contain dangerous toxins like methane, carbon dioxide, arsenic, etc. that can be detrimental for marine life.

Thermal pollution is a pressing issue, and its effects on ecosystems mirror the urgency of its implications for human health. Studies have revealed correlations between increased water temperatures and heightened health risks, including the proliferation of waterborne diseases and the potential for cancer due to elevated toxin levels. The infamous Camp Lejeune water contamination lawsuit stands as a stark reminder of the devastating consequences when industrial pollutants seep into water supplies, affecting the health of thousands of individuals. Understanding the gravity of such events emphasizes the critical need for stringent regulations and collective responsibility in addressing thermal pollution. Acknowledging the parallels between these environmental concerns and their impact on human health can serve as a catalyst for comprehensive solutions and preventative measures.

Such toxins can have a severe impact on the local aquatic ecosystem and the ecology.

It can make the marine creatures and plants vulnerable to different diseases and make it difficult for them to thrive in their natural setting.

Biodiversity Reduction

As already mentioned, thermal pollution can have a severe impact on the local aquatic ecosystem. This can affect the biodiversity in the locality.

Biodiversity is essential for maintaining the balance of the ecosystem. It is also needed for feeding the human population and maintaining human health.

When the pollution levels increase in water bodies due to thermal pollution, it can make the aquatic ecosystem unfit for many species.

Such a situation can lead to loss of life and a diversity of species living in the waterbody. It can impact the overall ecological balance.

Adverse Impact on Ecology

The ecological balance should be maintained at all costs. It is imperative for the survival of different species, including humans.

When waterbodies become suddenly polluted, it can cause toxin levels to rise.

A sharp rise in pollution levels can also reduce the DO levels, which can be dangerous for the aquatic flora and fauna.

Higher water temperature is not ideal for marine life. It can reduce their activity levels.

There are aquatic species that are highly sensitive to the rise in water temperature. Some of them can be sensitive to even a 1-degree rise in temperature.

Impact on Reproductive Systems

Thermal pollution causes a sharp increase in water temperature. It also causes an increase in toxin levels and a reduction in DO levels. This can negatively affect the reproductive systems of the aquatic species.

While they may still be able to mate for reproduction, the chances of defects in newborns will be drastically higher.

Once the water temperature rises beyond a certain level, it can start affecting the reproductive systems of aquatic species.

An excessive rise in water temperature can lead to the release of immature eggs. It can also affect the normal development of eggs.

Increases Metabolic Rate

Thermal pollution can affect the metabolic rate of aquatic species. It causes an increase in certain enzyme activities that force the species to consume more food. They would not have consumed more food if the water temperature was not increased.

Thermal pollution disrupts the stability of the food chain and the overall ecological balance. More food consumption means an increase in metabolic rate.

Loss of Species

Continued and sharp increases in thermal pollution can lead to loss of aquatic species.

The rise in water temperature and toxin levels are not ideal for the local flora and fauna.

Many species would find it difficult to survive in such conditions. This may even lead to their migration to a more suitable environment and the loss of marine species.

It can also cause a degradation of local biodiversity that is not good for the regional ecological balance in the long run.

How to Reduce Thermal Pollution

Reducing thermal pollution requires a coordinated approach and involvement of all relevant stakeholders.

The industry needs to play a significant role in this. They should adopt greener and more eco-friendly manufacturing processes.

They need to be committed to ensuring a cleaner and sustainable future. The following are the key ways to reduce thermal pollution:

Building Cooling Towers and Artificial Lakes

Industries can build cooling towers and artificial lakes for dumping the warm and polluted water.

These cooling towers and artificial lakes can store the warm water until it is restored to its original temperature. Once the water returns to its initial temperature, it can be discharged to the nearby water bodies.

This will help in keeping a check on the thermal pollution resulting from directly discharging warm and polluted water into the adjacent water bodies.

Saving Electricity

Electricity is a non-renewable energy source. It is also not cheap and requires costly processes.

Thermal power generating plants heat the water for producing electricity.

Thermal plants use a large amount of water and cause the water temperature to rise. This can give rise to thermal pollution on a large scale.

An effective way to address this problem is to save electricity. The more we save power, the lesser it needs to be produced from thermal plants.

Using Alternate Cooling Agents

Water is the most common cooling agent used in industries and even for domestic purposes.

The reason for this is easy availability and low cost of water. However, we fail to realize that heated water once discharged to a nearby waterbody, can cause thermal pollution.

If we use other cooling agents instead of water, thermal pollution can be controlled.

Air-based or oil-based cooling systems are good alternatives than using water as a cooling agent. The oil-based cooling system is efficient as oil can be used for multiple cooling cycles.

Releasing Heated Water in Less Vulnerable Regions

Industries can be planned and established in less vulnerable regions.

Discharging warm and polluted water in water bodies located near a dense population is very harmful. It affects the aquatic ecosystem and the overall ecology of the locality.

If contaminated water is released in water bodies that are in less vulnerable regions, it can minimize the impact on the ecosystem.

Plantation Along the Shorelines

Trees play an important role in maintaining ecological balance. They prevent the direct sunlight and sun’s heat from meeting land and water bodies.

If trees were not there, the surface area of waterbodies coming in direct contact with sunlight would increase drastically. This will lead to an increase in water temperature, which in turn would cause thermal pollution.

Afforestation is an excellent way to deal with the problem of thermal pollution. Planting more trees will also lead to a more stable and cleaner environment and ecosystem.