North Lakhimpur: Sarala Kaman (40) no longer walks to the familiar ghat of the Ranganadi with bundles of clothes balanced on her hip. For generations, women of Kadamiyal village under Nowboicha Revenue Circle in Assam’s Lakhimpur district have gathered along the riverbank to wash clothes, bathe and fetch drinking water. Today, the riverbed has turned into a stretch of sand.
Like many others in the village, Sarala now depends on a hand-pumped tube well for her daily chores. What was once a routine shaped by the rhythm of a flowing river has been abruptly altered by its absence.
For over a month, the Ranganadi — long regarded as the lifeline of riverine communities in Lakhimpur, has remained dry in its lower reaches. The river, which descends from the hills of neighbouring Arunachal Pradesh and travels nearly 60 km through dozens of villages before meeting the Subansiri at Pokoniaghat, has seen a sharp depletion in natural flow. Residents attribute this not only to an unusually prolonged dry spell but also to regulated discharge from the 405 MW Panyor Hydro Electric Project (PHEP) operated by North Eastern Electric Power Corporation (NEEPCO) upstream.
A winter without water
There has been virtually no rainfall in Lakhimpur district since mid-September 2025. The rainless period which typically lasts from late November to early January, extended well beyond its usual cycle this year. From October 2025 to January 2026, the district recorded almost no precipitation.
Meteorological data indicates that Assam received 603.8 mm rainfall during the 2025 monsoon — 37% below normal. Since January 2026, Lakhimpur has recorded just 0.5 mm against an expected 44.6 mm.
The consequences are stark along the stretch from Salmora to Kadamiyal and onward to Pokoniaghat, where the Ranganadi’s channel now lies exposed.
Binod Panging (50), a farmer from Salmora, says the crisis extends beyond household water needs. “Our cattle used to drink from the river during winter,” he says. “Now there is no water even for them.”
While farmers acknowledge that the dry spell has aided rabi cultivation, concerns are mounting over soil moisture depletion and falling groundwater levels.
Villages such as Na-Bhagania, Deobeel, Chamaguri, Potabeel, Khundu, Baligaon, Kharkati, Bor Goyan, Balijaan, Dambukial, Aamtola, Gopalpur, Jongkap and Khabolu are similarly affected.
Climate variability and altered river flow
Lakhimpur’s long-term rainfall record reveals growing variability. The district’s annual average rainfall is 2,949 mm across roughly 125 rainy days. However, the coefficient of variation is highest during winter (78%), indicating significant seasonal uncertainty.
A 2013 study by scientists from B.N. College of Agriculture, Assam Agricultural University, and the Regional Agricultural Research Station in North Lakhimpur found that in the preceding 27 years, annual rainfall was below normal in 12 years. Of these, three years experienced moderate drought (deficiency between 25.7% and 30.1%), while nine years faced mild drought (deficiency between 0.7% and 24%).
The Ranganadi basin in Assam spans 767 sq km and receives about 1,700 mm of rainfall annually, 80% of it during May to September. In the monsoon season, the river’s discharge ranges between 1,800 and 1,900 cumec per second, reducing to 170–180 cumec during winter.
However, environmental observers point to another structural factor — diversion of water at the PHEP dam at Yazali in Arunachal Pradesh.
During lean months (November to March), about 160 cumec of water is diverted for power generation. In a stretch of nearly 60 km downstream from the dam site to Pokoniaghat, the river has no major tributary to replenish its flow. What remains is often insufficient to sustain a stable channel, leading to progressive thinning and eventual drying.
Ecological costs
The drying of the Ranganadi carries implications far beyond domestic inconvenience.
The river sustains a network of wetlands — locally known as beels, that are rich in biodiversity and provide fish, cane and reeds. These wetlands depend on feeder channels connected to the main river. With prolonged drought and controlled discharge upstream, many of these channels have dried up, disrupting groundwater recharge and wetland ecology.
Since its construction in 1998 and commissioning in 2001, the PHEP has also been linked to increased siltation downstream. Residents recall embankment breaches and flood damage in multiple years — 1998 (Boniagaon), 1999 (Balijaan-Dambukial), 2008 (Bogolijaan), 2009 (Khundugaon), 2014 (Kharkati), and 2017 (Aamtola-Joinpur and Bogolijaan).
High silt loads combined with reduced discharge have altered physico-chemical parameters of the river — including turbidity, dissolved oxygen (DO) and biological oxygen demand (BOD), affecting aquatic habitats.
In January 2025, the river turned turbid following the release of industrial waste during maintenance work at the project’s power house.
A river at risk
During the monsoon, release of excess water from the dam often turns the river turbulent downstream. Howevwer, the same regulated flow leaves it depleted in the winter.
Experts warn that the combination of prolonged dry spells, increasingly attributed to climate change and regulated upstream discharge is pushing the river towards ecological stress.
For communities that have shaped their lives around its banks, the dried up river is more than seasonal variation. It signals a fragile balance between hydropower development, changing climate and riparian lives.