Bali water system: what eight groundwater basins and 89.08% coverage mean

Bali’s official environmental data show that water availability cannot be reduced to a single island-wide figure: the province has eight groundwater basins, while drinking-water service coverage reported in 2025 was 89.08%. These measures describe different parts of the water system and should not be treated as interchangeable.

How many groundwater basins does Bali have?

Bali has eight groundwater basins, according to the province’s 2025 statistical publication by BPS-Statistics Indonesia. A groundwater basin is a mapped hydrogeological area used to describe underground water resources; its existence does not mean that all water inside it is available for extraction.

Does 89.08% mean everyone has reliable drinking water?

No. The figure of 89.08% refers to reported drinking-water service coverage in Bali’s 2025 official data, not a guarantee that every household receives the same volume, quality or continuity of supply.

Coverage and resource condition are separate questions: a network may reach an area while seasonal shortages, source quality or local infrastructure affect actual service.

Why are the two figures often confused?

The groundwater-basin count describes the physical water-resource system, while service coverage describes access through drinking-water provision. They use different indicators, so neither figure measures Bali’s total water reserve or proves that supply is secure in every district.

What does the official data establish?

The clearest conclusion is that Bali’s water picture needs more than one indicator. BPS’s 2025 Bali statistical publication provides the provincial reference for the eight-basin count and the 89.08% coverage figure, while the Ministry of Environment and Forestry’s national statistics portal separately provides environmental and land-cover datasets for Bali.

Those sources support using the figures as starting points for assessment, not as a single measure of water abundance or household reliability.

Sources

• BPS-Statistics Indonesia Bali Province
• Ministry