Adverse payoffs of embankment
Koshi embankment breach victims
Embankments are the extravagant expenses of unnecessarily restraining the energetic rivers of the Bengal delta. These engineering structures are outmoded and even problematic with unfathomable maintenance costs. Lakes, ponds and rivers -- the Ganges, Brahmaputra and Meghna are integral parts of Bangladesh land features.
Drastic changes to natural landscape will render land ill suited for deluge causing poor drainage, prolonged floods and water pollution. Some suggest keeping embankments low so water and fertile silt can spread across land nurturing floodplains as was done before embankment era.
Flood control practices of modern day relied upon “just build the dike higher” approach despite repeated failures and without public debate. The disjointed efforts and nonalignment between river dynamics and landuse/human investments have resulted in larger emergency flood recovery expenditures.
We would rethink the argument behind flood control strategy that just failed, if we're conscious about the misery of people entrapped by embankments. During September 2008 Bangladesh flood 60 m of Goalando Dam disappeared in the Padma, flooding 20 villages. Efforts of local Water Development Board and Shena Kallayan were futile to save Debgram/Bhabanipur areas from flood losses due to swift current/high flow.
Yet, the writer wonders who so wrongfully has given the name “Kirtinasha Padma”. It is unrealistic human expectation to ask the majestic rivers of the Bengal delta to adjust to land-based enterprises as population increases and economy grows.
Given the effect of climate change and sea level rise, it has become increasingly critical to enhance awareness, at local and government level, to protect lakes, ponds and rivers from thoughtless development plans and human intervention.
To themselves from 2007 cyclone Sidr, 650,000 people fled to evacuation centers and 3.2 million more were evacuated, said Ali Imam Majumder, a senior government official in Dhaka. The 150 mph wind “swept in from the Bay of Bengal, buffeting the southwestern coastal areas within a 155-mile radius with heavy rain and storm surges predicted to reach 20 feet high”.
What are the technological means to adopt with respect to sea-level rise? It is undeniably true higher polders will not withstand the force of nature.
First, we ought to understand, fretting with the natural working of the rivers does not fare well. High priority should then be given to maintenance (or increase) of coastal forests that stabilize shoreline position and dually serve as a buffer for storm surges (Goodbred, Vanderbilt University). The time ahead will be particularly painful for people to watch or experience unless we open up to alternatives, such as active riparian land revegetation and forging partnership with watershed neighbours/civil society.
China's plan to build a series of dams in South Tibet worries us. Experts say, if either the water discharge or sediment load of the Ganges-Brahmaputra is tampered too much by damming/diversion in Nepal, India, China, the effects of sea-level rise could be potentially ominous for Bangladesh.
We wish fossil fuel emissions to be on a lower trajectory as the northeastern states of US implement “carbon cap-and -trade” law, modeled after 3-year old European experiment to tackle climate change. This is the most serious regional effort in the US that puts limit on CO2 emissions from utilities making them pay for each ton of pollutants (New York Times, Sept 16).
However, being at the mercy of developed nations to solve carbon crisis in the backdrop of economic gloom, Bangladesh needs to engage in talks with riparian countries and scrutinize its own policies. More industrial zoning (second Poverty Reduction Strategy Paper) without consideration to protect buffer areas along rivers could make the land vulnerable to erosion and flooding swapping with short run profit.
Diplomatic savvy and regional cooperation for uninterrupted Ganges-Brahmaputra water/sediment flow have become a monumental necessity and should be part of flood policy formulation at watershed scale for the subcontinent.
Of particular concern is China's Tsangpo (Brahmaputra) hydroelectric plans. If constructed, the power plant would produce 40 Giga Watt of power and would have twice the output capacity of the Three Gorges. The project would provoke tension between China and India, but the consequences could be fatal for Bangladesh, as the Brahmaputra carries a much bigger sediment load among all rivers that enter Bangladesh.
Intergovernmental long term buffer agreements at regional level and also at local level can protect river corridors from future encroachments. Flood losses and economic burden of rehabilitation of poverty stricken people plus government borrowing can be lessened by low cost, effective ecological solution to deal with river overflows.
Perennial grass that has grown deep roots in a hundred years has special water absorbing function. The Hokiloki Haor, Sylhet, one of the largest in Asia and all other such wetlands, dighis and lakes play the role of key attenuation assets and provide required storage during floods.
Chasing rivers with embankments is no solution. Chitra Padmanabhan writes about August 2008 Bihar floods of Kosi river in her recent article that five decades of embanking have increased Bihar's flood-prone area by a staggering two and a half fold. Jamuna embankment in Sariakandi is another failed protection rendering 3000 homeless at the section where it breached; several lakh were trapped in north Bengal (The Daily Star Sept 4).
We should redouble effort to disentangle ourselves from the investments in costly engineering projects that are band-aid solutions adding to recurring flood losses and untold human suffering. The long term challenge is to have predictable investments with less erosion.
The Worldwatch Institute research cited dams and channelization as the two most pervasive threats to freshwater ecosystems and fish propagation, dramatically hurting diversity and species abundance.
Shall we recall Tagore's teaching and not loose our way “into the dreary desert sand of dead habit”? People across US are changing the ways they look at rivers, said Tom Ardito, the director for the Centre for Ecosystem Restoration, from something that cuts a town in half to something that can bind a community together.
In the 19th century people treated rivers as source of hydroelectricity and in the 20th century as open sewers but in the 21st century, we've begun to realize that rivers are assets to be protected from pollution caused by dams or untreated discharges. The backwaters of impounded rivers are more turbid with low flushing rate, where pollutants sit forever.
Hydropower dams in China would shift environmental and economic problems to their future generations and create more climate refugees in Bangladesh. Solar, wind turbine, geothermal are all clean energy sources that can reduce fossil fuel dependency without bringing the world to its ecological knees. It is more of an ethical question.
Eco-friendly public transportation design and compact growth would leave open space for green villages, picturesque beauty of national parks/forests and scenic river ways in nodimatrik Bangladesh.
Rivers do not know political boundaries. It is a hope that upstream countries will be sensitive to the misery created by dams/barrages locally and beyond national borders.
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