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The hungry river: Looking through floods and silt in North Bihar

Exploring the economic benefits of silt to prevent floods in Bihar, India

Action on Climate Today (ACT) programme has assisted the Government of Bihar in developing a roadmap to estimate the amount of silt deposited in the Kosi basin and to assess the productive uses and economic benefits of silt to prevent floods in the state.

Of floods and their fury

'Floods were never seen as a disaster, they were a blessing to the village, until recently,' remarks Chandrasekhar ji, as he is reverently known. This was the same for many other villagers in Supaul district in North Bihar, which lies in the Kosi basin and is regularly affected by floods.

In North Bihar, local people dealt with floods as a way of life. 'In fact, floods were like daughters visiting their father's place; she is welcomed with open arms, but must go back to her abode,' chuckles Neelam, a middle-aged lady residing in the region and working with villagers on disaster preparedness and other associated issues.

However, in recent years, the intensity and frequency of floods have increased significantly. The Himalayan river has one of the highest annual sedimentation loads in the world, making it highly prone to flooding. And climate change-induced glacial melting leads to dangerously high water levels in the Kosi basin and potentially more silt, resulting in catastrophic floods and related disasters.

As a result, most of the villages have to relocate to the other side of the embankment during monsoons. Whenever the water level starts increasing, they have to displace themselves, their livestock, their crops – everything. This is an endless sequence of events, with houses built and destroyed and rebuilt. And, along with many other anthropogenic reasons, including several water resource development interventions, excessive siltation forms a central part of this problem.

'Kosi has been changing its course whimsically. We have seen it change its course twice in the past 10 years. The land that you are walking on was a deep flowing river a few years ago. All we can see now is a bed of silt everywhere, where usually we could find fertile soil,' says Baldev Jadhav, an old villager. Kosi has been referred to as the 'sorrow of Bihar', meandering and depositing abrupt heaps of silt on fertile fields and tearing away big chunks of land. During the monsoon, the huge amount of water coming in from the vast catchment area of Kosi makes it difficult to move for silt, with the result being overflowing. And in the summer it is spread across in patches of silt and water.

The silted land

'The amount of silt deposited in Kosi has only increased over the years,' says Ram Chandra Paswan, a primary school teacher in Naraiya village. He claims there has been a minimum increase of 5–6 inches of silt every year. River embankments are expansive, and the dilapidated school building can be seen standing in the midst of the accumulated silt.

Simultaneously, on the other side of the embankment, new low-lying land, known as chaur, is continuously being formed as a result of the silt deposits. This remains waterlogged throughout the year. Meanwhile, thousands of acres of existing arable land have become water logged, causing tremendous loss to crops and cultivation. Livestock-rearing has also been affected, as excessive waterlogging means limited land is left for grazing.

A suitable crop

Silt has also led to the shifting of many traditional crops, as silt prevents water retention capacity. Hence, a lot of crops that were traditionally cultivated in the region have had to be replaced. Hira Devi, a farmer who has seen a change in her crop cultivation, exasperatedly recounts her experience: 'I have been living in this village for about 25 years. Farming has been getting more difficult day by day. We resettle here and there; the land keeps changing year after year. You sow a crop on this land today and tomorrow you see dunes of silt everywhere. The sheer amount of silt and uneven land as a result of the shifting deposits of silt makes farming, which is the only occupation we have, very difficult. We are always uncertain of what tomorrow holds for us.' Meanwhile, uneven land makes it laborious to commute from one village to another. Irrigation of crops is another major issue: the area battles with either too little or too much water.

The story in the Ganga basin is the same, with similar repercussions for traditional cultivation of lentils – a major crop in Mokama Taal that is vanishing along the Ganges from the areas closer to the river as a result of massive quantities of silt deposition. Lentils have been replaced with wheat, which is relatively less profitable.

The solutions lie within

Getting rid of this silt is one plausible way to start solving this problem. But how to begin? Piprahari village in Supaul block has found a way to purify drinking water by using silt to make pots for drinking water. Excessive silt is also being used to build roads and in landfill for deeply excavated brick-making fields, etc. Most commonly, though, villagers are using silt to raise their houses and brace themselves against floods. 'Villagers have to find a way to adapt to these volumes of silt. If the government supports the poor farmers to dump silt in their respective agricultural low-lying land, it will be very helpful for them. Though it may not yield immediate results, it will become an upland, and the farmers can then use better than the waterlogged lands where nothing is possible,' says Chandrasekhar ji assuredly.

The communities are also looking at ways of adapting cultivation to grow crops that can be grown on silt instead. Even though Kosi silt is slightly deficient in terms of its nutrient value, some villagers suggest that alternate crops such as watermelon can be considered, by supplementing the silt with compost to improve its fertility. However, behavioural shifts in farmers' agricultural patterns will be needed if they are to move to newer and innovative ways of sand farming.

Creating a macro-change

While there is recognition of potential solutions, the Government of Bihar has been eager to explore and scale up the beneficial usage of silt. In collaboration with various research institutions, it was working on pilots involving products using silt and establishing the usage of silt. The ACT initiative has joined hands with the state government on this and is working on innovative methods to manage silt from the Kosi River. Estimating the amount of deposited silt and managing it for commercial purposes has been found to be among the top adaptation strategies to address the problem of recurrent floods caused by excessive deposits of silt.

Pankaj Kumar, ACT Team Leader, Bihar, says, 'The state government and ACT have found resonating needs to bring about a robust sediment management plan and share a similar vision of bringing change on the ground. A two-pronged approach has been adopted, one that covers the technical aspect and the other that looks at commercial viability of silt. The technical part aims to estimate the deposited and extractable silt in various stretches of the river. The commercial aspect looks at a commercial plan for usage of the dredged/removed silt.'

The study suggests that the excess silt has proven utility in reclaiming lowland and waterlogged areas, which can help protect the villages from recurring floods. It can also be used in low-lying agricultural fields, road construction, brick manufacturing, new landfills and perennial horticultural/medicinal crop cultivation, thereby leading to increased production and household income. The study also recommends integration of Mahatma Gandhi National Rural Employment Guarantee Act schemes with the silt management process.

ACT is looking at providing policy recommendations on how to manage the de-siltation process, and also proposes a comprehensive framework applicable not just to Kosi but also to other rivers in the state.

ACT and the Government of Bihar will bring together key stakeholders on a platform to initiate and structure a new way of discussing silt management in Bihar that will build a shared understanding of silt management in Kosi and the dual opportunity it presents in building resilience as well as economic development.

Friends of the river, and of the sand

Sediment management in the Kosi basin is a complex issue, and it needs a holistic approach that involves all stakeholders and, critically, the local community. People need to be encouraged to use the dredged silt for agricultural and other livelihood purposes. Policy-makers, researchers and civil society can capitalise on the awareness of the local community to develop robust methodologies and plans on desiltation.

'Yes, we have to cope. And that is why we are looking for solutions from within,' says Halima, an elderly farmer as she retires from her day-long work in the field. 'We do not want another 2008 flood-like event to happen ever again. And that is why we believe we must be friends with both the river and the sand!'

Silt: from impediment to solution

Excessive siltation in the Kosi basin is a massive problem and an impediment to the state's growth and development. Through ACT's interventions, the state now has an estimate of the amount of silt deposited and will be better positioned to develop a sediment management framework. Most importantly, the commercial benefits proposed can help transform this story of disaster to one of opportunity.

This article was previously published by ACT in On the Frontiers of Climate Change. Find out more about ACT's work.

Image credit: ACT on Flickr