Controlling river flooding has been a politically sensitive and conflicted issue in the naturally dynamic and abruptly shifting rivers of North Bihar in India [1,2]. With majority of the discussion being focussed on the impacts of engineering structures (dams, embankments, and their operation) on human vulnerability to flooding hazard [3,4,5], a new perspective on ‘flood control politics’ in this region [6,7] has emerged. This perspective has brought to the fore issues of serious conflict and marginality that millions of people face with centralized state and local non-state regimes of power and control, being trapped between embankments and highly exposed to flood risks due to the very structures that have sought to protect them [6,7,8,9,10]. Conflicts today are based on differential access to land and flood protection, blocked access to water bodies for fisheries and aquatic crop resources, and the constant reality of adjusting to displacement-induced poverty and socio-economic vulnerability [7,10,11,12].
In the dynamic riverscapes of the Ganga-Kosi region in eastern Bihar, monsoonal flooding, channel course changes, tectonic events, and high rates of sediment erosion and deposition are characteristic hydro-geological features [13,14,15,16]. The Kosi River, called the ‘Sorrow of Bihar’, has shifted its course by about 120 km westward in the last 250 years [6,14].
The eastern Bihar region supports high agricultural production on account of its fertile silt, but its dynamism may also be naturally adverse to permanent settlement by people [8,16,17]. Yet, throughout history, people have been settled in these regions in high population densities [10,12,18]. Some methods to adapt to and regulate flooding involved the creation of complex drainage networks and diversion channels across the floodplain to route silt-laden, fertile streams into agricultural fields and wetlands where fishing and aquatic cropping was carried out [19,20].
But in the 19th and 20th centuries, the drive for centralized control of revenue in the name of land protection from flooding and erosion led to the dominance of engineering solutions to flood control [6,8,11,19, 21,22]. This originated in the colonial ‘hydraulic bureaucracy’ with long embankments running for hundreds of kilometers built along riverbanks for flood control  causing a ‘great’ hydrological transformation of floodplain rivers [8,21,22,23]. The result was that oppressive regimes of control became fortified at the cost of river-dependent communities that were further marginalized and victimized . These communities included floodplain dwelling fisher folk, boat-ferrying people, aquatic crop growers, seasonal farmers, marginal livestock tenders, and other labouring castes. India’s Flood Control Policy in 1954  and an earlier committee constituted in 1928 recommended the intensive construction of embankments throughout Indian rivers. Within two decades, the construction of dams and barrages further aggravated the erratic modifications to river flooding, in tandem with embankment effects . The Birpur barrage on the Kosi at the India-Nepal border and irrigation canals along the western and eastern Kosi embankments, further controlled the river flow. In the dry-season, they have now made the Kosi a water-starved river by regulating its flow regime [12,28,29]. The extremes between which river flows fluctuated in this river were further aggravated, adding to the vulnerability of people directly dependent on river-based livelihoods [7,12,20,30]. Those thought to be “flood-affected” were perhaps more affected by “flood-control” instead [7,17,29,30]. Among those who did not permanently migrate could not get access to land beyond the embankments, and got trapped between the river embankments and the risk to them from flooding worsened multiply. The number of people who still suffer from this travesty ranges from 1.5 to 3 million in eastern Bihar . Embankment breaching by larger floods is also frequent, and points to the mismanagement of embankments by poor maintenance and repair work activities [20, 31]. The ‘cues’ that several floodplain dwellers might have traditionally tracked for pre-emptive and adaptive decision-making in view of imminent large floods, were severed by the embankment system [personal observations, reports, and references 7,20,31,32]. Embankments also broke the lateral connectivity between floodplains and river courses, which proved critical for fisheries production. Stocks of several fish species dependent on lateral migration into floodplain wetlands for breeding, juvenile nursery, and growth prior to returning to the river channel, have now plummeted [32,33]. Ground surveys suggest that nearly 80% of the fishery in the Kosi River has now ended . The bad management of drains dug out from the embankments for moving out excess water and sediment has led to higher impoundment of water within the river channel, submerging crops and other property and risking people’s lives. This is reflective of the hard-engineering nature of the embankment operations, most of which often do not work well under the highly dynamic sediment and water fluxes of these rivers [12,29,31]. Large floods and embankment breaches have also created enormous expanses of permanently and seasonally waterlogged areas. Aquatic crops and fish spawns are grown in many of these, yet, runoff from surrounding agricultural areas, unsustainable application of weedicides and pesticides in the waterlogged reaches, and the lack of drainage flows out of these areas have together caused declines in the water quality of these wetlands [11,12,31]. The wetlands have also turned into breeding grounds for multiple disease vectors, and malarial outbreaks are common in the region . Wage labour in farms and distant urban centres is the primary occupation of people with displaced livelihoods, and labour outmigration is now high in the area .
Embankments in the Ganga region have a slightly different trajectory. These embankments are mainly ripraps built along eroding meander banks using cement and RCC bags, but their life is not generally more than two flooding seasons (2-3 years, personal observations). Contracts are given out every year for embankment building, and heavy corruption is suspected in the process. The presence of the Farakka barrage downstream is said to have aggravated riverbank erosion in upstream reaches over the last 40 years , from Maldah all the way up to Bhagalpur. Mosquito-nets and stake-nets (that catch and destroy larval recruits of fishes) sprung up throughout the area following embankment building of this sort, and are a major driver of fishery conflicts here .
Overall, the environmental injustices met out to marginalized communities by flood control structures and management paradigms have proved to be highly problematic for livelihood security, ecological productivity, and human development in eastern Bihar’s Gangetic floodplains. Advocacy against the injustices of flood control, and activism for strengthening the capacity of affected communities for living with floods form the forefront of justice organizations in the area. Remarkable research by respected activist-scholars such as Dr. Dinesh Kumar Mishra, and civil society efforts by the Barh Mukti Abhiyan (Campaign for Freedom from Floods) have focused on mitigating these impacts by seeking softer solutions and adaptive management regimes. However, the embankment-dam regulation on river flows, erosion rates and sediment fluxes continues. The current scenario of livelihoods and justice is still uncertain and difficult, but grassroots action by civil society, broader trends of economic development, and cooperative management might hold promise for correcting some of these injustices in the future.