How Can We Clean Our Water?

Water pollution is a serious issue that affects water bodies like lakes, rivers, and oceans. It happens when harmful substances, such as waste, chemicals, or other particles, are released into these water sources, making them unsafe for animals and humans who depend on them. Water pollution can occur naturally, such as through volcanic eruptions or animal waste, but it is often caused by human activities. For example, factories release waste and chemicals, farms use pesticides and fertilizers, and people litter. These pollutants can make the water unsafe to drink, harm marine life, and disrupt nature's water cycle. The good news is that we can take action to reduce water pollution! People are encouraged to save water, avoid using harmful chemicals, and properly dispose of trash to help keep our water sources clean.

Sewage and wastewater

Another important method of treating sewage is called the activated sludge method. In this process, the sewage is put into a tank with lots of bacteria, which break down the harmful substances. The bacteria form clumps that sink to the bottom of the tank, leaving the cleaned water on top. This method is very effective and can remove most of the bacteria and solid waste from the sewage.

Some sewage treatment plants also use chemicals or light to kill any remaining bacteria that could make people sick. The solid waste removed during the treatment process can even be used to make methane gas or fertiliser for farms.

While sewage and wastewater treatment has improved over the years, it is still a big problem in many parts of the world. It is important to properly treat sewage and wastewater to protect our health and the environment.

Industrial activities

Water used by factories to process chemicals, cool engines, and wash things away is sometimes released into natural water bodies without proper treatment. This wastewater can be full of dangerous pollutants. For example, factories may release wastewater containing petroleum hydrocarbons, such as fuels (gasoline, diesel) and lubricants (motor oil), which can have devastating effects on the environment if they enter water bodies.

Additionally, industrial activities can also contribute to water pollution through oil spills. Oil spills occur when oil tankers crash or when there is an explosion at an oil well, releasing massive amounts of oil into the ocean. Oil spills can destroy marine habitats and harm or kill fish, birds, and other wildlife.

Furthermore, industrial activities can also lead to air pollution, which in turn affects water bodies. For instance, burning coal and other fossil fuels releases ash and other waste products into the air, contributing to air pollution. These pollutants can mix with water vapour and fall back to the earth as acid rain, which can turn lakes acidic and kill fish and other aquatic life.

To address water pollution from industrial activities, it is crucial to implement proper waste management and treatment practices. This includes treating industrial wastewater before releasing it into natural water bodies and ensuring that oil and other hazardous substances are handled and transported safely to prevent spills.

Agricultural activities

Water pollution is when waste, chemicals, or other particles make the water in places like rivers, oceans, and lakes unsafe and harmful for the animals and plants that live there. Water pollution can be caused by natural things like volcanoes, algae blooms, animal waste, and silt from storms and floods. But a lot of the time, it's caused by people. Human activities that cause water pollution include sewage, waste from farms, water and chemicals from factories, silt from construction sites, and littering.

Now, let's talk about how agricultural activities, or things that happen on farms, can cause water pollution and what we can do to fix it!

Farmers use fertilizers and animal manure to help their crops grow. These fertilizers contain nitrogen and phosphorus, which are important for plants. But sometimes, the plants don't use up all of these nutrients, and the extra nitrogen and phosphorus get washed away from the fields when it rains or snows. This extra fertilizer can end up in rivers, lakes, and even the water under the ground, which is called groundwater. Having too much nitrogen and phosphorus in the water can cause something called eutrophication, which means there might not be enough oxygen in the water for fish and other animals to breathe. It can also make the water unsafe for us to drink!

Farmers also use pesticides and herbicides to protect their crops from bugs and weeds. These are very strong chemicals, and when it rains, they can get washed away from the fields and into nearby rivers and lakes. Just like fertilizers, these chemicals can be dangerous for animals and plants living in the water, and they can even be harmful to people if we drink the water.

Another way farms can pollute water is through livestock, or farm animals. When it rains, the waste from these animals can get washed into nearby water sources. This waste contains bacteria and nutrients that can make the water unsafe for swimming or drinking.

There are lots of ways farmers can help reduce water pollution! Here are some of them:

• Using the right amount of fertilizer: Farmers can make sure they use the right amount of fertilizer at the right time of year and apply it in the right way. This will help prevent extra fertilizer from washing into the water.
• Planting cover crops: Farmers can plant extra types of plants, called cover crops, to keep the soil in place and stop it from washing away into nearby water sources.
• Creating field buffers: By planting trees, shrubs, and grasses around the edges of their fields, farmers can help catch and filter out nutrients before they reach a body of water.
• Reducing tillage: Farmers can avoid tilling their fields too often or too intensely. This helps improve soil health and reduces the chance of nutrients and chemicals reaching the water.
• Managing livestock access: Farmers can build fences to keep their animals away from streams, rivers, and lakes. This will help protect the banks of these water sources and prevent extra nutrients from getting into the water.
• Collaborating with others: Farmers can work together with scientists, government organizations, and community groups to find even more ways to reduce water pollution!

Oil spills

• Oil Booms: This method uses equipment called containment booms, which act as a fence to prevent the oil from spreading or floating away. Booms have three parts: a 'freeboard' that rises above the water surface to contain the oil, a 'skirt' placed below the surface to stop oil from escaping, and a cable or chain that connects and stabilizes the boom. This method is effective when the oil is in one spot and can be accessed within a few hours of the spill.
• Skimmers: After oil is contained by booms, skimmers are deployed onto boats to remove the oil from the water surface. Skimmers are machines designed to suck up the oil like a vacuum cleaner, and they can recover most of the spilled oil, making them economically viable. However, they can get clogged by debris in the water.
• Sorbents: Sorbents are materials that soak up oil through absorption (pulling in through pores) or adsorption (forming a layer on the surface). They make the cleanup process easier, and the oil can be recovered for re-use, preventing further pollution. However, sorbents become heavier after absorption and may sink, posing a risk to aquatic life.
• In-Situ Burning: This method involves igniting the oil floating on the surface to burn it off. In-situ burning can remove up to 98% of an oil spill, but it releases toxic fumes that can harm the environment and marine life. It works best on relatively fresh spills with a thick layer of oil.
• Chemical Dispersants: When oil cannot be contained by booms, chemical dispersants are used to accelerate the disintegration of oil. These chemicals are sprayed onto the spill from aircraft or boats, helping the oil to mix with water and making it easier for microbes to break it down. However, dispersants can create tarballs and negatively affect marine life, especially non-mobile organisms like corals.
• Hot Water and High-Pressure Washing: This method is used when oil is inaccessible to mechanical removal techniques. Water is heated to around 170°C and then sprayed with high-pressure wands or nozzles to flush the oil to the water surface, where it can be collected with skimmers or sorbents.
• Manual Labour: This method uses handheld tools like rakes and shovels to clean up oil and oily debris from shorelines, placing them in special containers for removal. It is labour-intensive and time-consuming but more economically viable, as it requires minimal training for workers.
• Bioremediation: This process uses specific microorganisms, bacteria, fungi, and algae to break down petroleum products into simpler, non-toxic molecules. Fertilizers may be added to provide nutrients for the microbes to grow and multiply. However, this method can take a long time, and the fertilizers may aid the growth of unwanted algae, negatively impacting marine life.

Stormwater runoff

There are ways to help reduce stormwater runoff and the problems it causes. One way is to make sure that rainwater can soak into the ground. This is called permeable paving, and it can be done by using special materials for roads, driveways, and patios that let water pass through. Another way is to plant more trees and plants, as they can help slow down and clean the stormwater before it reaches rivers and streams.

It's important to keep stormwater drains clear of litter and to pick up after pets so their waste doesn't get washed away by stormwater. We can also reduce the use of things like fertilizers, pesticides, and herbicides, which can be washed away by stormwater and cause harm to the environment.

Frequently asked questions