Logo

Logo

Tackling floods in West Bengal

The solutions lie in rainwater harvesting, revamping existing wetlands and water bodies through sharing of spillover water from flood prone rivers and resultant ground water recharge.

Tackling floods in West Bengal

Water harvesting

India, containing the state of West Bengal,is fortunate to be crisscrossed with a sizeable number of rivers. But flooding remains the most momentous natural hazard as its frequency and severity is increasing over recent decades West Bengal is of no exception, which has been affected by severe flooding, subjected to irreversible ecological and economic damages In last year, instances of torrential downpour are likely to be concentrated in shorter time span in association with successive water level rise have sloshed most of the districts in West Bengal. Furthermore, enormous cultivable lands in the form of vegetables, paddy (Aman), Jute, corn have severely been affected due to prolonged waterlog for consecutively more than a month, lead to massive economic loss in this year.

Hence, we have observed and experienced a large scale disaster in 2017 from flood and resultant domestic and economic ruin. But can this subversive flood effect be ceased? Yes, there is an extensive scope to mitigate as well as pluck up the frequent flooding and related damages to a large extent.

And we have certainly so many things to do about excessive rain, even to convert the devastating flood water into constructive water resource and to fulfill socio-economic needs. The solutions lie in rain water harvesting, revamping existing wetlands and water bodies through sharing of spillover water from flood prone rivers and resultant ground water recharge.

Advertisement

The government and decision makers have been unconquered to realize that rain is a gift of nature and water is vital for the sustenance of life and can never be licensed to be wasted. Resultantly, the basic issues like proper drainage are not getting due attention. If the rain water is rightly harvested without wasting, people are unlikely to suffer in the wake of drought.

 

West Bengal, floods, rain water harvesting
People crossing through flood waters.

 

First of all, we will have to be the most distinguished and deft water harvesters with a long term perspective to retain each drop of water, alter the running water initially crawl and subsequently stand and finally utilize the standing water for surface storage (Article by Jaydev Jana, The Statesman, dated 7 July, 2016) and at the same time recharge the sub soil and raise year round water table. Thus, judicious utilization of this over plus rain water with those regions, which are chronically deficient, is imperative.

In this regard we need to opt for rain water harvesting by constructing site specific appropriate structure in a planned and systematic way and without compromising on the existing ecology. Furthermore, resuscitating the already existing wetlands in the entire West Bengal and excavating additional land deep with necessity to hold the entire quantum of every possible form of water from rain water to ground water.

These water harvesting structures including wetlands provide for a multitude of ecological, economic, and landscape benefits, for instance in flood conveyance by decrementing run off velocity, water storage and groundwater recharge. Water resource is to be augmented by stocking rainwater available during the wet season and use the water for supplemental irrigation during lean period (summer season), associated with long dry spells.

Rain water harvesting with the help of scientific and technological know-how will lead to produce more crops per drop of water and increase both the crop yields and their incomes. Apart from these, the stored water can be utilized for domestic needs (rural drinking water), commercial fisheries, and other beneficial activities. This entire process is not that expensive but can generate farther rural employment.

As discussed earlier, West Bengal exhibits a unique assemblage of physiography, characterized by flat topography as well as medium and low land. The medium land topography, in association with very low ground water table in Bankura, Purulia especially during the dry spell, generally confronts with the relative scarcity of water, made it unsuitable for the intensive agriculture to some extent.

In this regard, we now have the greatest chance ever to be rid of flood damages and simultaneously augment water resources for surface storage and aquifer recharge by harvesting every drop of rainfall. How? By constructing ‘Hapas’ (concept was brought to Bankura District in 2006 by PRADAN, an NGO), a small deep pond dug out on farm land are mostly suitable to be located on medium or high land. Source: Rain water harvesting in West Bengal, (based on a report by P. Banerjee, 2012)

Rain water harvesting and storage through hapa formation and existing wetlands will play useful role in harvesting the surface run off during monsoon and then allow it to be used later in the form of improving more crop productivity by making the best use of water for providing protective irrigation.

Similarly, the dug out of ‘on-farm reservoir’, most common in flat topography is required to be installed in plain region to eradicate the flood phenomena as well as keep the water resource intact, provide supplemental and life saving irrigation, and to improve the surface drainage.

Thus, water harvesting through wetlands and other storage structures not only regulates and lessens flood impact but helps to maintain the ground water table, provide domestic water security and facilitate the farmers to bring more area under cultivation.

Being the largest producer of rice in India, agriculture is the mainstay of the population as well as economy, which accounts for the largest share of the labour force in West Bengal. But the success of agriculture depends on erratic and impulsive onset of monsoon rain, and a large tract of this state remains un-irrigated, leading to lower crop productivity.

 

West Bengal, floods, rain water harvesting
Hapas

 

And ironically, at the same time our source of sweet water in the form of rain is presently wasted during floods. Thus, a planned water resource development, to a certainty, will provide relatively inexpensive, adaptive, and resilient approach for ensuring the well-being of entire society and turn it into advantage, related with additional irrigation potential, food grain generation, enhancing household income, nutrition and public health as well as protection to a great number of people from periodic flood hazard.

West Bengal is prone to be regularly flood affected, which can be averted by adapting a few engineering technologies in a planned way including as much afforestation as possible at the catchment to stop further rain water runoff, accumulation of surface soil and resultant sedimentation. In order to increase the carrying capacity of rivers, systematic dredging is to be implemented at regular intervals into the prime rivers, and especially the Ganges, which has vast amount of sediments.

It is also necessry to construct site specific sluice gates to rejuvenate the already dried up channels or river linked water bodies by passing the spillover water from flood prone rivers and monitoring the functioning of lock gates to main the inflow and outflow within river channels. Further, all the existing lock gates of Farakka barrage are to be kept functioning properly to keep the flow of the Ganges intact.

In West Bengal, where much of the state’s populace is farmers, the major economy is directly related with agriculture, so proper planning and implementation is needed to avert frequent flood hazards which in turn will enhance food production and increase farm income.

The warning bells are ringing and we do not have much choice, either to become a part of the solution or remain a part of the problem. After all, we must follow what European Water Framework Directive said — “Water is not a commercial product like any other but, rather a heritage which must be protected, defended, and treated as such.” (Article by Jaydev Jana, The Statesman, dated 7 July, 2016).

The writer is a research scholar, University of North Bengal

Advertisement