Water Pollution: Trends, Causes, And Our Future

Water pollution is a pressing issue that has dominated the list of natural disasters over the past 50 years. While the Clean Water Act has driven significant improvements in US water quality since 1972, it is clear that water pollution remains a critical issue. This is especially true in the case of developing nations, where inadequate sanitation exposes 2.4 billion people to water-borne illnesses. Climate change, industrial and agricultural waste, and leaky irrigation systems are among the leading causes of water pollution, threatening both human health and the environment.

Water Pollution: Increased or Decreased?

The Clean Water Act

Water pollution is a pressing issue, with many water systems stressed, and some rivers, lakes, and aquifers drying up. Water pollution has various sources, including agricultural runoff, untreated human wastewater, and industrial waste.

The CWA made it unlawful to discharge any pollutant from a point source into navigable waters without a permit from the EPA or an authorized state. This includes industrial, municipal, and other facilities whose discharges go directly into surface waters. The Act also set wastewater standards for the industry, requiring industries to reduce or eliminate point source pollution in surface waters.

The EPA has also developed national water quality criteria recommendations to address specific toxic pollutants, with maximum levels deemed safe for humans, wildlife, and aquatic life. The EPA provides significant financial resources to assist utilities in repairing and replacing their infrastructure, as well as technical assistance to improve their resilience to extreme weather.

The CWA has had a positive impact on reducing water pollution. Sewage from homes and businesses now receives treatment before discharge, and industry-specific discharge standards prevent over 700 billion pounds of toxic pollutants annually from being dumped into US waters. The rate of wetlands loss has also decreased substantially compared to pre-Clean Water Act times. However, there is still work to be done to achieve the Act's goals of ensuring fishable and swimmable waters and eliminating pollutant discharges.

Climate change and water pollution

Water pollution has multiple sources, including agricultural runoff, sewage overflow, and industrial waste. Climate change exacerbates the problem by increasing stormwater runoff, which degrades water quality and spreads pollutants over larger areas. Higher air and water temperatures promote the growth of algae and microbes in water bodies, leading to Harmful Algal Blooms (HABs). These HABs threaten the availability of source water and increase the need for drinking water treatment.

The impacts of climate change on water pollution are already being observed. Heavy rainfall and changing precipitation patterns can overwhelm sewage systems, causing raw sewage to overflow into waterways. Rising temperatures and drought conditions can also reduce water levels in rivers, lakes, and reservoirs, leading to increased pollutant concentrations and higher treatment costs.

The Environmental Protection Agency (EPA) in the United States has been working to address water pollution and the impacts of climate change. The Clean Water Act, implemented by the EPA, has driven pollution controls since 1972 and prevented the discharge of over 700 billion pounds of toxic pollutants annually. However, climate change continues to pose a significant threat to water utilities and infrastructure, and more needs to be done to adapt to and mitigate its effects.

Water supply and sanitation systems that can withstand climate change are crucial. Climate-smart agriculture, efficient water use, and watershed restoration efforts can help reduce the demand on freshwater supplies and improve water quality. Additionally, addressing cybersecurity risks in water and wastewater systems is essential to prevent unsafe levels of bacteria or chemicals in drinking water. Overall, climate change is increasing water pollution and threatening the availability and quality of freshwater, requiring urgent action and adaptation measures to ensure clean and safe water for human and ecosystem health.

Water scarcity

Agriculture is a significant contributor to water scarcity, accounting for 70% of freshwater usage globally. However, it is also a significant source of water pollution, with fertilizers and pesticides contaminating water bodies and affecting both humans and other species. In addition, agriculture often utilizes leaky irrigation systems and inefficient application methods, resulting in the waste of 60% of the water it consumes.

Addressing water scarcity requires an integrated and inclusive approach that considers the complex and varying factors driving this issue across countries and regions. Efficient and effective water management is essential, along with the adoption of sustainable water use practices. Organizations like UNICEF and WWF are working to increase access to safe water, improve water management, and promote conservation and protection.

Water quality testing

Water pollution is a pressing issue that has attracted the attention of governments and environmental organisations worldwide. Despite the Clean Water Act driving pollution controls since 1972, water pollution remains a significant problem. This is due to factors such as climate change, agricultural runoff, and insufficient wastewater treatment.

Parameters for Water Quality Testing

Water quality tests examine various parameters to determine the condition of a waterway and the presence of specific contaminants. These parameters include:

• Temperature: Water temperature influences aquatic ecosystems and can indicate the presence of thermal pollution.
• PH: A measure of acidity, with lower pH indicating higher acidity. Acidity affects water taste and can impact human health, with water that is too acidic potentially causing illness.
• Turbidity: A measure of the cloudiness or clarity of water, affected by suspended particles like sand, silt, or organic matter.
• Salinity: The concentration of salts in the water, which can impact its suitability for different uses.
• Nitrates and Phosphates: Excessive levels of these nutrients can indicate agricultural runoff and lead to harmful algal blooms.
• Chloride: Found in higher concentrations in contaminated water, impacting taste and corroding pipelines.
• Ammonia: Increased by the decomposition of organic matter and the use of chloramine in water disinfection.
• Conductivity: A measure of the water's ability to conduct electricity, influenced by the presence of ions and affecting its suitability for different purposes.
• Odor: The smell of water, which can indicate the presence of certain contaminants or impurities.
• Sediment: Testing for the presence of suspended solids, such as sand or silt, which can impact water clarity and filtration.

Types of Water Quality Testing

• Bacterial Testing: This involves analysing water samples for the presence of harmful bacteria, such as E. coli, which can cause serious health issues when consumed.
• Mineral Testing: A wide range of mineral tests are available to detect the presence and concentration of minerals and ions in the water, including chlorine, chloride, nitrate, nitrite, lead, copper, iron, zinc, potassium, and sodium.

Water-related disasters

The Intergovernmental Hydrological Programme (IHP) supports member states by contributing to the formulation of scientific tools, methodologies, and knowledge to address water scarcity, hydrological extremes, and sediment transport and management. Climate change, including increased frequency and intensity, has reduced water security and hindered efforts to meet Sustainable Development Goals.

The impacts of water-related disasters are exacerbated by urbanization and the degradation of natural environments. Loss of natural "buffers" such as trees, river bank-side vegetation, wetlands, and coastal mangroves reduces protection from flooding. Rapid urbanization can also lead to concrete taking over large areas of land, causing runoff to flow too rapidly into storm drains and overwhelming the system, resulting in catastrophic flooding.

To address the complex interrelated water challenges under conditions of climate change, UNESCO-IHP provides a platform for scientific knowledge and tools to reduce flood and drought risk and vulnerabilities. UNEP also promotes nature-based solutions such as river reconnection, reforestation, terracing, and sand dams.

Frequently asked questions