In the flood-prone Barak valley of southern Assam, where monsoon floods often leave villagers without clean drinking water, terra filters installed by a non-governmental organisation have become a lifeline.
Barak valley in southern Assam and perennial floods have long been notoriously synonymous. Surrounded by a sea of floodwater every monsoon, thousands of villagers in Cachar district live with the paradox of “not a drop to drink”. However, a simple technology ensures that Rakhal Dey Laskar of Sarashpur village has clean water to drink.
Laskar, a farmer in his late 40s, wades through the recent deluge to reach a whitewashed concrete tank fitted with a terra filter, set up among a copse of betel nut trees in front of his home. The water, pumped by a motor, is clean, free of iron and other pollutants. His family needs 40-50 litres a day, enough to fill two steel pitchers for drinking and cooking.
However, frequent power cuts leave the pump idle for hours, forcing Rakhal to wait for water.
“There have been power cuts during floods over the past few days. It takes 2-3 hours to fill one pitcher,” lamented his younger brother Keshav Dey.
Southern Assam, recently battered by Cyclone Remal, has been reeling under incessant rain and strong winds. Floodwaters have inundated vast tracts of fields and villages, affecting over 200,000 people across nine districts, including Cachar.
Gumrah, a tributary of the Barak river, has breached its banks, flooding Laskar’s home and other buildings in Saraspur. Though the water hasn’t yet reached Rakhal’s verandah, it lingers, refusing to recede.
Despite these challenges, the access to drinking water has improved compared to past floods. Two years ago, during the second wave of floods in June, floodwaters entered their home and stayed for more than a fortnight. The family collected rainwater, boiled it for hours, or rowed a neighbour’s boat 5km to Gumrah Bazar to buy and store mineral water. Many neighbours had little choice but to drink floodwater.
The terra filter, installed by SEEDS India in January 2024, has been a lifeline. SEEDS India, an NGO working towards disaster resilience and climate change adaptation, has set up 10 filters in flood-prone locations across Cachar, benefiting approximately 2,000 people.
The filters, made from a mix of red clay, river sand and sawdust, are half-baked to develop perforations that remove nearly 99 percent of turbidity, 95-100 percent of microorganisms, and 90-95 percent of soluble iron, colour and bad odour, improving the water’s taste.
Each filter can process 1,000 litres a day, drawing water from underground aquifers through a motorised suction pipe system. Elevated platforms ensure that these filters remain functional even during floods, effectively preventing water-borne diseases.
While the Cachar installation is still new, the terra filters have a proven track record. In 2016, five terra filters were installed in Bihar’s Sonbarsa. These filters successfully provided clean drinking water during the devastating floods of 2017, showcasing their potential to transform communities.
However, challenges remain. Residents in Cachar have reported issues with the rectangular membranous covers of the filters, which have not been securely fastened. This can lead to contamination by insects, worms and dead leaves, especially during storms.
“We need to clean the filters at least twice a week to avoid drinking contaminated water. The NGO recommended cleaning just twice a month, which isn’t sufficient,” Rakhal said. His brother Keshav added: “If they had added connection pipes to drain out contaminated water, it would have saved us the trouble of frequent cleaning.”
The filters are connected to pre-existing borewell hand pumps without considering the aquifers’ depths, leading to water shortages.
“When you switch on the motor, the water gets pulled in no time. And then there is no water,” said Rakhal.
According to SEEDS India field officer Dwarka Karmakar, if the depth had been adequately assessed, the water could be pumped, filtered and recharged more efficiently. He offered a solution: “When there is electricity, the motor pulls in water from the aquifer in no time. But the aquifer remains empty and takes time to get refilled from gravity-fed wells. One needs to switch off the electricity and turn it on again for the next batch of water.”
In neighbouring Mahadevpur, similar filters remain unused. Poorly secured covers and contamination fears deter residents from trusting the filtered water.
“Filter or no filter, it’s the same. During floods, we have to use the tubewell if it’s not submerged under water,” said Monika Das, queuing to fill her steel pitcher, adding that her family needs 100 litres daily, far more than the family’s terra filter can provide.
While Rakhal and his family have taken it upon themselves to clean the filters twice a week, the community in Mahadevpur views this as an excessive burden, with no time to spare.
The gap isn’t in the technology itself but in community mobilisation.
“Technological innovations need to be demystified for the community,” said Eklavya Prasad, managing trustee of Megh Pyne Abhiyaan, a trust working on water distress in eastern India. “A volunteer from the community, paid by the community, can usually sustain the use after installation.”
As floodwaters persist and power cuts continue, the terra filters represent a vital advancement in providing clean water to flood-affected communities. Amidst the deluge, Rakhal’s determination to provide safe water for his family highlights the resourcefulness of Saraspur’s residents.
The lead image on top shows residents of Madhavpur village, who are facing technology gaps in using the terra filters. (Photo by Aatreyee Dhar)
Aatreyee Dhar is a Village Square Fellow 2023-24. She works as an independent journalist in Assam.
