Tukad Yeh Mawa records steep dry-season drop in Bali river levels

Denpasar — Tukad Yeh Mawa in Tabanan has recorded one of Bali’s steepest documented dry-season river level declines in 2026, with average water levels dropping from around 0.409 metres in the wet season to about 0.008 metres in the dry season, according to data from the Bali–Penida River Basin Agency cited by local media on 9–10 September.

The figures come from hydrological measurements at 20 monitoring points across river basins in Gianyar, Tabanan, Jembrana, Karangasem, Klungkung and Badung, compiled by the Balai Wilayah Sungai (BWS) Bali–Penida.

Local outlets reported that the comparison reflects average water levels in the wet and dry seasons, rather than single-day readings, and that the data set covers conditions up to August 2026.

Sharp declines across multiple rivers

According to reporting based on BWS Bali–Penida data, Tukad Yeh Mawa’s decline was the deepest among the 20 monitored points.

Other rivers in Tabanan also showed significant drops, though less extreme. Tukad Yeh Otan, Tukad Balian, Tukad Yeh Aba and Tukad Yeh Sungi were all reported as experiencing dry-season decreases, with Tukad Yeh Mawa’s figures standing out as the most severe in the regency.

Media reports citing the same data set noted that Jembrana regency recorded the next-largest declines after Tukad Yeh Mawa. Tukad Yeh Embang’s average level fell from about 0.757 metres in the wet season to roughly 0.212 metres in the dry season, a drop of around 72%, while Tukad Yeh Sumbul declined from about 0.416 metres to 0.152 metres, or about 63%.

In Badung, Tukad Badung Hulu was reported to have fallen from approximately 0.296 metres to 0.125 metres, a decline of about 58%, while Tukad Ayung Hilir dropped more modestly, from around 1.321 metres to 1.141 metres, or roughly 14%.

The same data set placed Tukad Petanu Hulu in Gianyar at about 0.689 metres in the wet season and 0.433 metres in the dry season, a decline of around 37%.

By contrast, some monitoring points showed relatively small changes in average river level through the dry season. Tukad Pakerisan in Gianyar and Tukad Melaya in Jembrana were both reported with minor declines compared to the sharper drops elsewhere.

Dry-season pressure and drought warnings

An official from BWS Bali–Penida quoted in local coverage said the declines in river levels were in line with ongoing dry-season conditions and underscored the need for tighter monitoring and prudent water management.

Separately, the Bali Provincial Disaster Management Agency (BPBD) and the Meteorology, Climatology and Geophysics Agency (BMKG) have issued early warnings for meteorological drought for September 2026, indicating that parts of Bali are in a watch-to-alert status for prolonged dry conditions.

BPBD Bali stated that, based on BMKG’s climate outlook for early and mid-September, the province remains in the dry-season period, with reduced rainfall and a continuing risk of drought in some areas.

BMKG’s national early warning for meteorological drought for the second ten-day period of September included Bali among provinces with districts classified from “watch” to “alert” status, reflecting below-normal rainfall and lengthening dry spells.

Seasonal context and El Niño influence

Earlier in July, BPBD Bali and BMKG highlighted the strengthening of El Niño and warned of heightened drought risk, noting that the peak of the dry season in much of Bali was expected around August–September 2026.

Local reporting has linked the sharp declines in river levels, including at Tukad Yeh Mawa, to this broader pattern of a strengthened dry season and El Niño-related pressure on water resources.

While the available river-level data provide a clear snapshot of hydrological stress at specific points, they do not yet offer a detailed, site-by-site assessment of ecological impacts, irrigation losses or household water shortages for each individual river. Agencies have instead used the combined hydrological and climate information to call for continued measurement, water conservation and close local monitoring of drought conditions.

Sources

• Balipost – "Tinggi Muka Air Sungai Bali Turun Tajam, Yeh Mawa Anjlok 98 Persen"
• PojokBali – "Data BWS Bali-Penida: 20 Titik Sungai Alami Penurunan Muka Air, Tukad Yeh Mawa di Tabanan Anjlok 98 Persen"
• BPBD Provinsi Bali – "Peringatan Dini Cuaca/Iklim Dasarian II September 2026 Provinsi Bali"
• WartaTrans – "Kemarau 2026, Sejumlah Sungai Indonesia Menyusut Ekstrem"
• Gobaligo – "Berita Bali｜Gunung Api di Indonesia Meletus Beruntun"
• BMKG – "Peringatan Dini Kekeringan Meteorologis"
• MetroTVNews – "Indonesia Berpotensi Mengalami Kekeringan hingga 20 September, Ini Daerah dan Kategorinya"