Water quality has emerged as a vital aspect that determines how a country can successfully manage its environment, infrastructure and health. In many developed countries around the world, access to clean, pure drinking water is not up to chance.
Instead, various aspects such as water sources and environmental protection policies help determine water quality. In various countries with excellent water quality, advanced engineering solutions are used along with resource management to ensure that the water remains pure and free from any pollution at every stage. Understanding how these systems work can help determine the extent to which different countries are able to achieve near-perfect water quality and how they manage to maintain these results over time.
According to World Population Review, see below the list of the top 10 countries with the best water quality in 2026, measured as part of the annual Environmental Performance Index (EPI).
List of top 10 countries ranked by water quality
| nation | a result |
| Germany | 100 |
| UK | 100 |
| Italy | 100 |
| Greece | 100 |
| Switzerland | 100 |
| Finland | 100 |
| Ireland | 100 |
| Norway | 99.9 |
| Luxembourg | 99.8 |
| Canada | 99.7 |
*Higher scores reveal greater availability of safe drinking water.Source: World Population Review
Countries with the best water quality
Germany
In Germany, water quality standards are determined by a federal regulatory framework based on the EU Water Framework Directive. Municipal water supplies rely on groundwater sources, which are naturally filtered through geological layers before being pumped.
Water treatment plants use a multi-step purification process that includes activated carbon filtration and oxidation.
UK
In the United Kingdom, water quality management involves oversight by agencies such as the Environment Agency. Water sources include reservoirs, rivers and aquifers, which undergo extensive treatment before consumption. Techniques used include membrane filtration and UV treatment.
Italy
Water quality in Italy has been improved through a combination of Alpine water sources and organized municipal water treatment systems. Mountain water sources have relatively low pollution, which helps reduce the intensity required in the water treatment process.
Greece
In Greece, high water quality is ensured by natural filtration, especially in areas of limestone geology, such as insular and coastal aquifers. Desalination plants are used to increase fresh water resources in areas with natural water scarcity
Switzerland
Switzerland is one of the countries with the most controlled water system in the world.
The country relies heavily on natural sources such as lakes and alpine springs. Much of our drinking water does not need to be treated because it is naturally pure.
Finland
Thousands of lakes in Finland are an abundant source of fresh water resources. Both groundwater and surface water resources are used in Finland, with appropriate treatment processes implemented.
Ireland
Ireland gets much of its drinking water from rivers and lakes, supported by treatment plants designed to address organic and microbial risks.
Infrastructure improvements in recent years have focused on upgrading legacy systems to meet more stringent standards.
Norway
Norway benefits from a glacial and mountainous landscape that naturally protects its water sources from pollution. Surface water, especially from lakes, is the primary source.
Luxembourg
Despite its small size, Luxembourg maintains highly efficient water management systems. Groundwater is the main source, supplemented by surface reservoirs.Regulatory frameworks impose strict quality standards, while modern treatment facilities ensure compliance. Investment in infrastructure has reduced losses and maintained system reliability.
Canada
In Canada, vast reserves of fresh water provide a strong foundation for high water quality. Lakes and rivers, including the Great Lakes system, are major sources. Water treatment standards are governed at both the federal and provincial levels. Advanced filtration and disinfection systems are widely used in urban centers.