Water Crisis Puts Pressure on Indonesia’s East Kalimantan

SAMARINDA, EAST KALIMANTAN – A growing water shortage is putting pressure on parts of Indonesia’s East Kalimantan province as a prolonged dry season triggers drought and seawater intrusion into the Mahakam River.

In Samarinda, authorities distributed 98,000 liters of emergency clean water on September 22 to around 2,440 residents affected by disruptions to the water supply. Chloride levels in the Mahakam River exceeded the safe threshold of 250 parts per million (ppm), forcing several water treatment facilities to adjust their operations.

Andri Rachmanto Wibowo, head of the Kalimantan IV River Basin Authority in Samarinda, said the emergency supply was delivered directly to affected communities.

“The emergency clean water supply of 98,000 liters was distributed directly to reach 2,440 affected beneficiaries,” Andri said on Tuesday, September 22.

The problem extends beyond Samarinda.

In North Penajam Paser Regency, home to Indonesia’s new capital Nusantara, the local disaster agency has distributed 822.2 tonnes of clean water through 170 deliveries between August and September. The supplies have reached communities in Sepaku, Babulu and Penajam districts.

The Mahakam River Is Becoming Saltier

Seawater intrusion has emerged as a major challenge for Samarinda's water supply.

As seawater moves further upstream, rising chloride levels make raw water increasingly difficult to process into drinking water.

At one point, chloride levels in the Mahakam River reached 1,085 ppm, forcing the Sungai Kapih water treatment facility to temporarily stop production.

Authorities had previously distributed another 160,000 liters of clean water to drought-affected areas across East Kalimantan, including North Penajam Paser, Paser and Samarinda.

In North Penajam Paser, authorities have also completed an interconnection between the water network in Waru and the Lawe-Lawe raw-water source to strengthen supplies during the dry season.

A New Challenge for Nusantara

The water situation is particularly significant because some affected areas are located around Nusantara, Indonesia’s new capital.

The Nusantara Capital Authority has prepared several measures to address the risk of prolonged drought, including increasing water supplies from Sepaku Semoi Reservoir and exploring groundwater reserves through planned drilling. Geoelectric surveys have been conducted with Gadjah Mada University as part of the groundwater exploration process.

The situation highlights a challenge that goes beyond infrastructure development. As East Kalimantan's cities and the new capital continue to grow, authorities must also ensure a reliable supply of water for communities and urban areas.

For East Kalimantan, the 2026 dry season is becoming a test of water security as drought and seawater intrusion put increasing pressure on existing water sources.