Water quality has become one of the key aspects that determine how successfully a country manages its environment, infrastructure and health. In various developed countries around the world, access to clean and pure drinking water does not happen by accident. Rather, various aspects such as water sources and environmental protection policies help determine water quality. In countries that enjoy excellent water quality, advanced engineering solutions are combined with resource management to ensure that water remains pure and free of any contamination at every stage. Understanding how such systems work can help determine how countries are able to achieve near-perfect water quality and how to maintain such results over time.Check out the list below of the 10 countries with the best water quality in 2026, according to the World Population Review, as measured as part of the annual Environmental Performance Index (EPI)
List of top 10 countries for water quality
*Highest scores indicate greater availability of safe drinking water.Source: World Population Review
Countries with the best water quality
Germany
In Germany, water quality standards are set through a federal regulatory framework based on the EU Water Framework Directive. Municipal water supplies rely on groundwater sources that are naturally filtered through geological formations before being pumped. The water treatment plant uses a multi-step purification process, including activated carbon filtration and oxidation.
U.K.
In the UK, water quality management involves oversight by agencies such as the Environment Agency. Water sources include reservoirs, rivers and aquifers, and undergoes extensive treatment before drinking. Technologies used include membrane filtration and UV treatment.
Italy
Italy’s water quality is improved through a combination of mountain water sources and urban regulated water treatment systems. Mountain water sources are relatively less polluted, which helps reduce the intensity of water treatment processes required.
Greece
In Greece, natural filtration guarantees high water quality, especially in areas with limestone geology such as islands and coastal aquifers. Desalination plants are used to increase freshwater resources in areas with scarce natural resources
Switzerland
Switzerland has one of the best-controlled water supply systems in the world. The country relies heavily on natural resources such as mountain lakes and springs. A large portion of drinking water does not require treatment because it is naturally pure.
Finland
Finland has thousands of lakes with abundant freshwater resources. Finland is utilizing groundwater and surface water resources and implementing appropriate treatment processes.
Ireland
Most of Ireland’s drinking water comes from rivers and lakes, supported by treatment plants designed to address organic and microbiological risks. Infrastructure improvements in recent years have focused on upgrading older systems to meet more stringent standards.
Norway
Norway benefits from glacial and mountainous landscapes that naturally protect water sources from pollution. Surface water, especially from lakes, constitutes the main water source.
Luxembourg
Despite its small size, Luxembourg maintains an efficient water management system. The water source is mainly groundwater, supplemented by surface reservoirs.The regulatory framework enforces strict quality standards, while modern processing facilities ensure compliance. Infrastructure investments minimize losses and maintain system reliability.
Canada
In Canada, abundant freshwater reserves provide a solid foundation for high water quality. Lakes and rivers, including the Great Lakes system, are major sources. Water treatment standards are administered at the federal and provincial levels. Advanced filtration and disinfection systems are widely used in urban centers.

