By R.K. Birjit Singh
Water hits the headlines of print and electronic media under two conditions. Number one, when there is not enough of it and secondly, when there is excess of it, what is known as flood and drought. Whenever, there is flood and it is to be followed by drought. The river flood associated with the valley areas of Manipur are due to the heavy rainfall over the catchments and the vanishing of a number of wetlands. The frequent landslides in the hills upset the regime of the river and the rivers use to carry considerable amount of silt and have a tendency to change their course. The forest in the catchments areas of the river and streams are the most single crucial factor for controlling landslides, flood and drought condition of an area. The green vegetation of the forest protects soil erosion from the action of the rain and absorbs rainwater and releases it slowly over a period of time thereby preventing flash flood and drought.
The forest area of the state is 17,418 sq. km (FSI, 1997) which means that 78% of the land is under forest cover. But this forest cover data remains in the book whereas the green lungs of the state is vanishing at an alarming rate of 78.5 sq.km annually which is much higher than the international trend of 13 million hectares per year and another 27% of the forest i.e 4702.86 sq.km is under Jhum cultivation.
Flash floods are floods of short duration with a relatively high peak discharge. They arise from the local precipitation of extremely high intensity and mostly in the sub-montane tracts. The river washes away the flood plains when the discharge is nearer to or above the danger level. The water spills over the embankments and flood plains through breaches. People of the valley areas of Manipur welcome a low and medium flood of short duration because the floods use to flush the garbage’s of the rivers like as they have converted these streams and rivers as dumping site of their domestic waste. These small river and streams which is the life line and nerve of the people of Manipur are dried up due to the indiscriminate deforestation in the catchments areas and their carrying capacity has been reduced to a drastic level and are either converted into nala or drain. As the carrying capacity of these rivers has been reduced during high floods the floodwater enters through breaches into the doabs, interfluve areas and fill up the low-lying areas. Sometimes flood water remains stagnant for weeks together damaging the crops and houses and invites water born-diseases.
Flood fill up the wells and community ponds with muddy water and brings a serious crisis in the drinking water situation along with the collapse of houses of mud and wood leading to human causalities and death of domestic animals.
It not only damage property and endangers the lives of humans and animals, but has other effects as well. Rapid runoff causes soil erosion as well as sediment deposition problems downstream. Spawning grounds for fish and other wildlife habitat are often destroyed. High-velocity currents increase flood damage; prolonged high floods delay traffic and interfere with drainage and economic use of lands. Bridge abutments, bank lines, sewer outfalls, and other structures within floodways are damaged, and navigation and hydroelectric power are often impaired. Financial losses due to floods are commonly crores of rupees each year.
Control of Floods:
The basic methods of flood control have been practiced since ancient times. These methods include reforestation and the construction of levees, dams, reservoirs, and floodways (artificial channels that divert floodwater).
Although dams have been used for many centuries, their primary purposes were to build up water reservoirs for irrigation and other domestic uses and to create power. Only recently have they been constructed specifically for flood control.
The Hoover Dam on the Colorado River, the reservoirs in the Miami Conservancy District, and dams of the Tennessee Valley Authority (TVA) have demonstrated the value of this method. When the tributaries on which these dams are located are at their normal level, the dams operate solely to produce power and provide water for various purposes. During time of high water the dams operate to slow down the flow. The dams closest to the origins of the tributaries restrain the floodwaters while the dams farther down slowly release their normal reservoirs and are drained. Then the floodwaters are released to each succeeding dam and are finally emptied into the main river, the capacity of which has been increased by straightening and deepening.
Through the centuries people have created a flood problem by cutting down trees and digging up the vegetable cover of the soil, thus increasing soil erosion. Cultivation decreases the ability of the soil to retain water and increases runoff. Vast land areas along the headwaters of rivers throughout the world have been laid waste by intensive Jhum cultivation and subsequent erosion. Flood control in these areas has been directed to restoring vegetation and instituting efficient methods of soil management, such as crop rotation and contour plowing.
Another method of flood control is the construction of floodways on the lower reaches of rivers to divert floodwaters. The rivers are widened at certain points and allowed to overflow. Inundation of certain confined areas prevents the flooding of other areas. The Egyptians have used regulated flooding for thousands of years. Many areas in the Nile Valley depend for their continued fertility on periodic flooding because the soil deposited by sedimentation from floodwater is very rich.
When the people are suffering from flood, the Ministers, MLA’s and concerned officers along with the district administration are very happy secretly within their mind. Because, at least some crores of rupees is going to be released in the name of flood. In beginning they will shout rhetorically like the roaring forties and will suspend and transfer some of his subordinate officers only to siphon the amount mean for flood relief in their ever thirsty and greed pocket. The real relief of the affected people will be distributed only through AIR or DDK. This is not a new think in this trouble torn state of Manipur. After all, our netajee’s and officers are expert in fishing in trouble water and is a part of our rich tradition and culture.
Sometimes, the logic of our planners and wisdom of the Government is strange and wonderful. They will be alarmed only when the flood breached the embankments of the river and engulf the mass population and their croplands. The flood cycle is known to the people of Manipur. Flash flood during the month of May and June do not cause much damage but during the post monsoon season brings severe damage to the valley area. Then, why we do not have a proper long and short term planning for flood control measures in Manipur. Implanting bamboos to protect the banks and raising their level will not solve any problems of flood. As we make higher and higher the level of river bank, subsequently, the river bed will follow the trend.
The ancient Chinese built levees to raise the banks of the Huang Ho (Yellow River) on the supposition that the confined river would then deepen its channel to contain the maximum flow. The result, however, was a raising of the riverbed, because the sedimentary deposit of alluvial soil previously distributed over the entire flood plain during annual flooding was confined to the river bottom. In 80 years the level of the river rose as high as 21 m (70 ft) above the surrounding plain. In 1887 one of the worst floods in recorded history occurred when the Huang Ho broke through the levees, killing more than a million people.
We need a master plan home work, if we are serious enough to control flood. Let us make use of our rusted compass laying unused for decades in the department and make a joint coordinated tour and trip of IFCD, PWD, PHED, Forest and Environment and Horticulture department including DST to the catchments areas and riverheads where our brothers are leading a hard life. By making a proper contour and survey with involvement of the people of the area let us construct co-ordinated groups of small dams and reservoirs on the headwaters of the streams that lead into the main rivers, so that water can be stored during periods of heavy runoff and released gradually during dry seasons. The Public Health and Engineering Department will do the job for taking up water supply schemes from these dams for the surrounding villages, Electricity department to see the possibility of installing micro-hydel project to electrify the villages, Forest department to take up income generating plantation programmes like, Seri, Eri, medicinal plants and reforestation with the horticulture department. The PWD will increase the connectivity of surface transport. Forget about the flood in the valley, it will solve 60 percent of the issues and problems which tore apart the valley and hill.
Inadequate policy and regulations, combined with non-transparent and non-participatory process is at the root of many of the water and flood management problems plaguing the state. There are very limited resources in the Govt. system for quick and effective flood and other disaster response. In absence of a risk assessment, vulnerability analysis and community need assessment; flood relief and disaster mitigation activity at the district, state, block and community level becomes what the disaster managers at different level perceive. There is no disaster management information system at any level of governance in Manipur. In the absence of such a system, the disaster management is operating on information, which is neither reliable nor authentic. There is a need for community resource mapping which can play a vital role in resource mobilization for disaster management at the community level. There is a need to evolve a state specific management policy not only for flood but for the entire natural and man made disaster to address the indigenous situations of the state.