Pollution's Impact On Drinking Water Sources

Water pollution is a critical issue that poses a threat to both human health and the environment. It occurs when toxic substances enter water bodies, degrading water quality and endangering the health of millions worldwide. These contaminants can come from various sources, such as industrial waste, agricultural runoff, improper waste disposal, and sewage treatment plants. The effects of water pollution are far-reaching, impacting drinking water sources, human health, aquatic ecosystems, and industries that rely on good water quality. With pollutants like bacteria, viruses, chemicals, and excess nutrients finding their way into water systems, the natural balance of ecosystems is disrupted, leading to negative consequences for both plant and animal life.

Groundwater Contamination

Groundwater is a major source of freshwater, used for drinking, agriculture, and industry. Approximately one-third of the global population depends on groundwater for drinking water. However, urbanization, agricultural practices, industrial activities, and climate change pose significant threats to groundwater quality.

Contaminants can be natural or human-induced. Natural sources of contamination include seawater intrusion, brackish water, poor-quality surface water, and mineral deposits. Human activities that contribute to groundwater contamination include leaking fuel tanks, toxic chemical spills, pesticides and fertilizers applied to lawns and crops, leakage from septic tanks and waste disposal sites, and industrial discharges.

The effects of groundwater contamination are far-reaching, impacting human health, the environment, and socioeconomic development. Contaminated groundwater can introduce toxic substances, such as toxic metals, hydrocarbons, trace organic contaminants, pesticides, nanoparticles, microplastics, and other emerging contaminants, which pose risks to human health and the natural environment.

Industrial Activities

Types of Industrial Waste

The types of industrial waste generated can vary widely and include cafeteria garbage, dirt and gravel, masonry and concrete, scrap metals, trash, oil, solvents, chemicals, weed grass and trees, wood and scrap lumber, and similar wastes. This waste can be further classified into hazardous and non-hazardous categories. Hazardous waste may result from manufacturing or other industrial processes and includes things like ammonia, solvents, petroleum, and pesticides. Non-hazardous waste, on the other hand, does not meet the EPA's definition of hazardous waste but can still have detrimental effects on the environment if not properly managed.

Effects of Industrial Waste on Drinking Water

The release of industrial waste into water bodies can have severe consequences for both the environment and human health. Many hazardous substances from industry are difficult to biodegrade and accumulate in water sediments. This can lead to the illness and death of fish, crustaceans, and other aquatic creatures, disrupting the biodiversity of waterways.

Additionally, through cracks in the ground, polluted water from rivers and contaminants from water sediments can infiltrate groundwater sources, thereby affecting drinking water supplies. For example, the carcinogenic substance chlorobenzene, used in the textile industry and the manufacture of insecticides, dyes, pharmaceuticals, and fragrances, has been detected in food and drinking water supplies.

Preventing Water Pollution from Industries

To address the issue of industrial water pollution, several measures can be implemented:

• Compliance with environmental legislation and regulations: In the US, the Clean Water Act (CWA) and the National Pollutant Discharge Elimination System (NPDES) provide a framework for managing industrial wastewater.
• Implementation of sustainable industrial wastewater recycling systems: Membrane systems and vacuum distillation systems can treat and recycle wastewater, reducing the amount of fresh water needed and lowering disposal costs.
• Source control and pollution prevention: By identifying the water streams generated in production and analyzing their composition, industries can work towards reducing or treating wastewater effectively.
• Investment in new, sustainable technologies: Developing and adopting innovative technologies can help minimize industrial pollution and its impact on drinking water sources.
• Policy changes and effective enforcement: Governments and regulatory bodies must implement and enforce policies that promote sustainable practices and hold industries accountable for their environmental impact.

Improper Waste Disposal

Plastics are especially dangerous as they can be ingested by animals or cause entanglement, leading to injury or death. For example, discarded fishing nets, plastic bags, and other waste can entangle and kill marine animals such as turtles, birds, and fish. Additionally, chemicals and toxins released from improper waste disposal can contaminate bodies of water, altering pH levels, oxygen concentrations, and temperature, making it challenging for aquatic organisms to survive.

Another consequence of improper waste disposal is the destruction of aquatic vegetation. Aquatic plants are responsible for filtering out pollutants and supplying oxygen to other animals. Without these plants, bodies of water become colder and dirtier, leading to a deterioration of the entire ecosystem.

Furthermore, improper waste disposal can introduce toxic substances that accumulate in fish and other water organisms. As larger predators consume these contaminated creatures, they ingest concentrated poisons, posing a significant threat to their health.

The impact of improper waste disposal on drinking water is also concerning. Water supplies can become contaminated with pollutants like bacteria, viruses, and chemicals, rendering the water unsafe for human consumption. This contamination can occur through industrial discharges, agricultural runoff, and the breakdown of waste in water sources.

In addition to the environmental and ecological consequences, improper waste disposal also has economic implications. The fishing industry, for instance, suffers directly from water pollution as contaminated fish populations decline, affecting food sources and the livelihoods of fishermen.

Overall, improper waste disposal has far-reaching effects on drinking water and the environment, underscoring the importance of proper waste management practices to protect ecosystems, wildlife, and human health.

Sewage Treatment Plants

The treatment process can be divided into three levels: primary, secondary, and tertiary (or advanced) treatment. Each level targets different types of pollutants and impurities, with the goal of making the water safe for release into the environment without causing further pollution.

Primary treatment uses screens and settling tanks to remove solids, which make up about 35% of the pollutants. Screens remove large objects such as sticks and garbage, while settling tanks allow sludge to settle and scum to form on top, which are then skimmed off. This step removes up to 50% of the biological oxygen demand (BOD) substances, 90% of suspended solids, and up to 55% of fecal coliforms.

Secondary treatment uses bacteria to digest the remaining pollutants. The wastewater is mixed with bacteria and oxygen, which helps the bacteria to digest the pollutants faster. The water is then taken to settling tanks again, leaving it 90-95% free of pollutants. This step removes about 85-90% of BOD and suspended solids, and 90-99% of coliform bacteria.

Tertiary treatment targets dissolved substances such as colour, metals, organic chemicals, and nutrients. One of the biological treatment processes is called Biological Nutrient Removal (BNR). This process uses bacteria in different conditions with varying amounts of oxygen to digest the contaminants. It is highly effective in removing phosphates, with a removal rate of over 90%, while traditional processes remove much less.

Overall, sewage treatment plants play a crucial role in treating wastewater and reducing water pollution. By employing a combination of physical, biological, and chemical processes, these plants help remove impurities and pollutants from sewage, making it safe for discharge into natural bodies of water without causing further harm to the environment or human health.

Eutrophication

The effects of eutrophication on drinking water include:

• Taste and odour problems: Algal blooms can cause taste and odour issues in drinking water, leading to increased costs for bottled water and alternative drinking water treatments.
• Contamination: Eutrophication can contaminate drinking water sources with bacteria, viruses, and chemicals, rendering the water unsafe for human consumption.
• Health risks: Drinking contaminated water can pose serious health risks, including gastrointestinal issues, respiratory problems, skin infections, and even life-threatening diseases.

Frequently asked questions