How about dismantling the embankment?

Embankments help lessen the suffering.

During the flood every year water experts bring in issues making this embankment a debatable structural intervention and then quickly disappear with the recession of floods leaving engraved the basic question in the minds of the common people on the justifiability of the embankment. It will as such be worthwhile to pre-discuss the issue of embanking more widely and interactively to decide upon addressing the future status of the embankment for the purpose of protection.

The concept of embanking germinated from within the social science of raising 'aile' for land separating, terracing, salt cultivating, fishing and other farming practices. The living geometry of this 'aile' with the changing dimensions of rural poverty over time triggered embanking. The modern embankments are the dynamic version of social engineering. The composite system of the embankment is designed for protection of flood, removal of drainage congestion and making provision for irrigation including prevention of salt water intrusion and storm generated surges.

The embanking is a simple building technology but highly complicated in terms of its performances in hydraulic functions. It provides increased flood-free secured land for agriculture, enhanced degree of safety to human lives, livestock, settlement, industry and infrastructure, wider accessibility, multiplicity of cropping intensity, higher crop yields, improved drainage, culture fisheries, and reduced hazards from floods and surges. On the contrary, impeded drainage, reduced soil moisture ,degradation of soil-water quality, loss of flooded habitats, changes in hydrological regimes, increased agrochemical runoff, restricted navigation, increased siltation, severity of flooding, land erosion, enhanced incidence of water-borne diseases are few of the listed negative impacts.

Many of the control structures, chiefly embankments, proved to be counterproductive. Side by side, much less consideration has been given by the water professionals to the sustainability of rivers or canals and their water quality in designing an embankment project for consumptive or non-consumptive use of water culminating in fatal disruption of stream's hydraulic equilibrium. Experts argue that embankment obstructing the flood pass is the main cause of flood related disasters and drainage hazards in the country and therefore stand in advocating for open channel flow; thereby managing foods by coping with floods. Observations also register that the embanking does not perform because of its failure during extreme hydraulic events, the time of its real need. Some experts, however, admit that yet the country has little option other than embankments to protect the backshores with mitigation plan drawn on environmental and social impact assessments.

Zooming in one such in-site embanking, an international expert named John Briscoe revisiting the village Fatehpur of Matlab under Comilla district embanked back in mid-70's under Meghna-Dhonagoda Irrigation Project after 25 years described the changes brought in by the embankment as benefits in myriad of ways, in the obvious physical health of most people; in the rarity of a smallpox-scarred face; in the quality of people's clothes; in the quality of their houses, water supply and sanitation facilities; in the number of schools and attendance at these; in the emergence of women into the public domain; in the intensity of work both on the land and in the bustling markets which had sprung up everywhere; in the use of modern techniques for agriculture, aquaculture and transport. The changes were huge and almost all positive what pinpointed 'embankment' as the primary source that protects the people and the property.

The benefits in terms of economic returns of most of the embanking projects are shown close to zero because such assessment is singly based on the agricultural output, the known objective. The other positive impacts i.e. embankment serving as roads providing micro-trading facilities, bringing qualitative changes in ecology, supporting community mobilisation, linking with national level programmes and accelerating infrastructural growth of all other sectors such as health, education, and food are not taken into account. The engineers, economists, social scientists and researchers have thus made embanking debatable. But the population ambient to embankment and their livelihood dependent on hydrological characteristics of the region and the hydraulic behaviours of its water fronts, to the contrary, count different from what the experts say. Embankments are never however accused by those people protected.

The low-lying deltaic Bangladesh's land surface is annually flooded by more than 20 percent. Severe flooding may inundate 36 percent and in case of extreme hydraulic event the flooding exceeds 68 percent. In addition to regular astronomical high tides of 2 to 6 meter, there are cyclones and cyclone generated storm surges. The already experiencing climate change induced impacts within next 20 years are foreseen to permanently inundate 18 percent of the country's land mass. The impact of much talked about possible tsunami is little known. City seminars deliver these data often without any reference to the contribution of embanking.

The offset hydraulic parameters of streams are though responsible for devastating floods and erosion rendering rural people homeless, unsustainable interventions on rivers or canals, particularly earthen embankment for controlling flood, further worsen them. Truly, the nature with respect to time within the Universe is in a continuous state of equilibrium. Tsunamis, earthquakes, floods, cyclones, hurricanes, storm surges, droughts, wild fires, land slides, snowmelts whatever called the natural disasters are only few macroscopic balancing efforts of the nature in support of life on earth. All these were there in the past, are in now and shall be in future. Disasters have all along been the life line for transformation and supply of food and fibre on earth. Embanking therefore may not be expected at ensuring safety from disasters of any magnitude.

The National Water Management Plan has an analytical finding that only 2 percent incremental food production per annum is enough to meet the future demand of 40 percent absolute increased national population over the next 20 years. This is achievable simply by ensuring the improved and adequate maintenance of the embanking projects. But the question now is even beyond -- protecting life and other sector infrastructure. Embankments are no more the individual jigsaw units. The built-in composite embankment system is very much an integral part of the country's hydrological features.

The system may therefore be mathematically modeled to carry out study for managing floods with respect to detention, drainage and diversion of upland flow locally and regionally in more comprehensive manner for immediate future planning. Perspiring with impacts of floods on nation's economy almost every year there is no point in pondering about dismantling the embankments.

Md. Saeedur Rahman, is a retired Chief Engineer of BWDB.