Water becomes contaminated when it comes in contact with a harmful substance to living beings or the ecosystem. These harmful substances are called contaminants and may be the result of any human activity or can come from a natural source, such as a forest fire. Normally we have to worry more for water pollution created by human activities, since natural contamination is much smaller and does not overwhelm the ability of ecosystems to heal. Humans, by contrast, produce pollutants in large quantities and steadily to the point that water pollution has become a global problem.
Production from fossil fuels directly and indirectly pollutes the water. Extraction and transportation of oil spills resulting in causing lasting damage to the seas.
Pollution temperature in nuclear power plants
In nuclear power plants, large amounts of water are used to prevent overheating of the components needed to generate energy. Although this water is not contaminated by any toxic substance, is heated and hot water is returned to the same river from which it was obtained. This creates a hot spot on the river that changes the ecosystem from the point of entry to downstream.
More information: What are the clean energy?
Industrial agriculture contributes greatly to water pollution. Only meat production causes a third of the pollution of freshwater in the world. Fertilizers, herbicides and pesticides applied to agricultural fields contaminate nearby water bodies, including groundwater. Waste of animals in factory farms also drained into rivers and lakes, causing dead zones. An example is the dead zone in the northern Gulf of Mexico that covers more than 20,000 square kilometers and in part due to waste from the agricultural industry the southern United States.
Most man-made surfaces do not absorb water. The flooring, the ceilings and other artificial surfaces divert water from rain and snowmelt that would normally be absorbed by the earth and cause drain with great speed and volume, sweeping the contaminants in their way as heavy metals, road salt, oil motor and trash.
Factories and other centers of industrial activity are important sources of water pollution. In countries lacking regulatory laws to protect water quality, liquid toxic waste is dumped directly into rivers or buried in barrels often suffer leaks and end up contaminating groundwater. Unfortunately some of these practices persist despite the regulations, although the incidence is much lower.
The mines are infamous for exuding toxic sludge. Waste rock excavated and treated to remove unwanted minerals are filtered, poisoning rivers and lakes nearby with heavy metals and sulfur oxides, which causes extreme acidification of water bodies. Ecosystems and human communities that have the misfortune to live near an active or abandoned mine pay with their health.
In nature, vegetation density corresponds directly to the amount of precipitation: the more rain, more plants of all types that can filter water and remove pollutants before they reach rivers, lakes and seas. When we cut the trees, we plow the land, fill the wetlands and built cities concrete, we interrupt the water cycle. We pulled the purifying activity of plants, bacteria, fungi, insects and all other living beings working to remove contaminants from the air, soil and water. Instead we add more contaminants and a structure that deposited in a more concentrated form, directly in water bodies.
We can refrain from daily practices that pollute the water from our homes.
The waste remains in the environment and finally ends up in the sea, where it causes numerous problems for marine animals. Plastics are the main culprits. Learn how to reduce the amount of plastic you use.