1. The average annual rainfall is low being around 700mm with the number of rainy days being around 50.
2. The soil is mostly clayey and so infiltration of rain water is low. Moreover such soils tend to get waterlogged if subjected to flood irrigation.
3. The underlying rocks are basaltic and sedimentary having low porosity and permeability and so their capacity to store water in underground aquifers is limited.
4. The average evapo-transpiration rate for the area is very high at about 2100 mm and so a considerable amount of the rainfall evaporates immediately. In the dry periods during the monsoons and later the moisture retained in the soil gets evaporated. A large amount of the water stored in surface storages big and small too gets evaporated.
Thus traditionally the agriculturists of this region had adopted practices that made the most use of the soil moisture and conserved the ecosystem to ensure a sustainable output. However, from the decade of the nineteen seventies a more intensive agricultural system was introduced involving the use of external inputs such as hybrid seeds, chemical fertilisers and higher irrigation either through canals from dams or through groundwater extracted with pumps. This has led to a growing shortage of water and the need for water governance to regulate its availability and use. The problems created by the external input system of agriculture and the lack of water governance in the western Madhya Pradesh region is illustrated here with the example of the basin of the Man River which is a tributary of the Narmada River.
The characteristics of the Man River basin which make it ideal for such a study of water governance are as follows -
• The basin spans the three distinct agro-ecological zones of the Malwa plateau, Vindhya hills and the Nimar plains.
• There is a serious problem of over extraction of ground water in the basin.
• There is a large dam in the basin affecting water governance drastically.
• There is a significant tribal population in the basin.
• The basin has a considerable reserved forest area which is mostly degraded.
The water availability is more or less related to the rainfall in the area and in more than half the years the rainfall is below the average values and these are the years when the kharif crop is also under water stress leading to lower than potential yields. The water use in agriculture in the kharif season in a normal year is well supplied by the rainfall and does not require the application of irrigation. In years of less than normal rainfall there is little scope for providing protective irrigation and effectively this results in water stress and lower yields.
Consequently what is more of a concern from the water governance point of view is the water used for the irrigated crops in the rabi season. An estimation of the rabi season water use revealed that while in 1989 the total water demand was 1100 million cubic meters this rose to 1321 million cubic meters by 2005.Thus there has been an increase in water demand over the period by 20%. This water demand was being met mostly by groundwater in the Malwa region and with groundwater and some lift irrigation from streams with return flow in the Vindhya region. In the Nimar region the component of lift irrigation is higher because of the enhanced flow in the Man river downstream of the Man dam due to seepage under the dam and from the canals. This water demand has to be compared with the average annual water being precipitated on the total geographical area which is about 3000 million cubic meters. Thus the water demand for irrigation in 2005 was 44% of the total annual precipitation and was mostly met from groundwater. Estimations done in hard rock areas show that natural recharge is never more than 11% of the total annual rainfall. Thus, the current level of extraction being four times higher, the groundwater aquifers have become over exploited and the surface storages too are not capable of meeting this theoretical demand leading to water stress and lower yields of crops in the Rabi season in recent years.
Thus a "tragedy of the commons" has been created. Normally in the case of a non-renewable resource the user has to trade off resource use between successive time periods to optimise production in the long run because more the resource is used the more is its extraction cost and more is its scarcity value. The water in the deep confined aquifers in dry hard rock regions is akin to a non-renewable resource because it has accumulated over thousands of years from the minimal amount of percolation into these aquifers that has taken place annually. Thus when this water is pumped out in large quantities in a particular year far in excess of the minimal recharge that is taking place, the water level goes down and in the next year the extraction cost will be greater and this will go on increasing with time. However, in a situation in which this extraction cost was rendered close to zero by electricity being made free and the water itself being a common property resource did not have any price attached to it and neither did its depletion result in a scarcity value, all the farmers tended to use as much water as they could get as in the long run the water would be finished even if a few farmers adopted a more conservationist approach.
Situations in which there are public goods with no well defined property rights as with groundwater either the state has to step in to regulate its use through fiscal or legal measures or there has to be communitarian command over its use as markets fail. However in this case the state too failed by adopting the opposite stance of subsidising the greater use of water.
The crunch came at the turn of the century when the Madhya Pradesh government as part of the conditions for getting a loan from the Asian Development Bank for restructuring its power sector had to begin charging farmers for electricity supplied to them at cost plus profit rates determined by the Madhya Pradesh Electricity Regulatory Commission. The ADB imposed this fiscal prudence on the government so as to ensure that it could pay back the loan that was being given. The prolonged bleeding of the Madhya Pradesh State Electricity Board due to the free power supplied earlier had hampered the addition of new power generation capacity and so the quantity and quality of power supplied to rural areas also began to suffer. The shortfall had to be made up by purchasing power from the national grid and this too pushed up the cost of electricity further. In additon to this heavy withdrawals of water had led to the severe depletion of the confined aquifers and many of the tubewells had either gone dry or were yielding much less water. Most of the blocks in Western Madhya Pradesh were declared to be either critical or over exploited in terms of ground water resources.
On the surface water utilisation front too there are problems. There are a number of points on which the operation of the Man Dam as it stands today can be critiqued -
1. Inadequate and Poorly Constructed Canal Network
Contrary to the design the Right Bank Canal Network has been developed more than the Left Bank Canal Network. In both cases the main canals, the distributaries and the minors have been built less than the design length. Moreover the construction of the canals is very poor and in many stretches the proper trapezoidal section and dimensions as per the designs have not been adopted, even for the main canal. Moreover, even though it is claimed in the final cost estimate report that 18.42 km length of the main canal has been lined this is not the case in reality as only those sections of the main canal that have been constructed above the ground level through earth filling to maintain the level have been lined and this length is far less. In fact the total final cost of lining is a meagre Rs 2.7 crores. This together has led to the main canals being unable to take the design flows and consequently the actual flow in the Left Bank Canal varies between 2 - 3 cubic meters per second and that in the Right Bank Canal between 3 - 6 cumecs.
2. Seepage and Waterlogging
The Water and Power Consultancy Services (WAPCOS) was engaged by the Madhya Pradesh Government to study the problems that might beset the canal network in the form of seepage given the kind of soil through which the canals were to pass and suggest remedies. The report of WAPCOS submitted in 1980 assumes the following estimates for losses -
1. Lined System
a) Main Canal and Branches - 4 cusecs/million sq. ft.
b) Distribution System - 6 cusecs/million sq. ft.
2. Unlined System
a) Main Canal and Branches - 15 cusecs/million sq. ft.
b) Distribution System - 20 cusecs/million sq. ft.
The costs are then worked out for the canal system for different scenarios of unlined and lined systems. This is done by estimating the area of command for each scenario which goes on increasing as the system is progressively lined. Consequently even though the cost of lining goes up the cost per hectare comes down as the increase in the command area due to lining more than offsets the increased cost of lining as follows -
1. Wholly Unlined - Rs 13,675/Ha
2. Main Canals and Branches Lined- Rs 12,380/Ha
3. Lining upto 40 Ha blocks Rs 11,033/Ha
4. Lining upto 8 Ha blocks Rs 10,607/Ha
The Detailed Project Report of the Man Dam goes on to say on the basis of this - " In view of this and the recommendations of the World Bank in their Staff Appraisal Report no. 3260-IN of February, 1981, lining of the whole canals system upto 5 to 8 Ha blocks is proposed in the Man Project." Contrary to this, as mentioned earlier, only a small part of the main canals have been lined and so huge seepage losses are taking place. So great are these losses, given the poor construction of the canals, that as soon as the main canals are charged the drainage nullahs begin to flow with seepage water and they continue to do so throughout the irrigation season. This huge amount of water then flows to the tanks that have been constructred in the command area and overflows their waste weirs and finally reaches the Man river unutilised downstream of the dam.
Naturally the command area has shrunk considerably as there is not enough water flowing in the canals and in the 2007-08 season the "Elan" was for only 5000 Ha or one third of the design command. The actual irrigation took place in only 2765 Ha in 15 villages by the Right Bank Canal and 2153 Ha in 14 villages by the Left Bank Canal for a total of 4918 Ha. This in addition to the irrigation from water taken from the distributaries through field channels also includes the irrigation done from the seepage water collected in tanks. The incompleteness of the canal network and the meagre flow in the main canal itself, depleted by seepage, has led to the farmers using their own means to lift water from the canals quite audaciously as shown in the picture below where a pump has been installed by a farmer on the canal regulatory structure itself.
Moreover, the heavy seepage has also led to waterlogging in several farm plots close to the main canals. A survey was conducted in the 2007-08 irrigation season of the ways in which water was being drawn by the farmers and the number of farmers who had been affected by seepage. This revealed that there are considerable problems with regard to drawal of water from the canals what with drawal by motor pumps and siphons exceeding by 80.8% that being supplied directly. There are also a high number of farmers affected by waterlogging due to seepage. The proportion is as high as 30.1%. These farmers have had to either abandon this land or construct drainage channels to divert the seepage water. At least a thousand hectares or so of land is so affected by seepage and despite several petitions given by the affected people to the administration, no remedial action has been taken.
Not surprisingly there is tremendous competition for canal water towards the lower reaches where the flow becomes very low due to seepages and unauthorised drawals higher up. Regulatory structures have been broken by the farmers and they draw water at will as shown in the picture below where villagers have constructed temporary bunds on the canal to divert water into their distributaries at the cost of villagers downstream. These villagers maintain a day and night vigil at this point to ensure that villagers downstream do not break their bunds.
3. Unsuitability of Command for Flood Irrigation
60.2% of the command area consists of land that is unsuitable for flood irrigation without extensive land levelling and bunding work and yet the project was sanctioned without any provision in the budget for such land levelling work. In fact in addition to this considerable length of drainage channels also need to be built but this finds only cursory mention and a provision of a paltry Rs 9.42 lakhs in the original DPR of 1982. However, later this absurdly low provision also has been done away with in the final cost estimate of 2004. This omission has obviously been done to keep down the costs of the project and artificially improve the cost benefit ratio. Costs of afforestation and soil conservation in the catchment have also been ignored and the oustees of the dam have been denied proper rehabilitation. All these economisations have added to the problems of the dam as the silt load has gone up and the oustees have not only remained in the submergence area to practise drawdown agriculture but have also engaged in agitation and litigation under the banner of the Narmada Bachao Andolan.
Thus, here the whole question of the appropriate method by which to ensure the presence of soil moisture in most of the lands in the command area during the Rabi season comes to the fore. Given that the final cost of the project in 2004 was Rs 176.75 crores (as compared to the design cost in 1982 of Rs 35.94 crores) and the additional irrigation achieved is only 4000 Ha (5000 Ha minus the 1000 Ha lost to waterlogging), the cost per hectare of irrigation provided turns out to be a whopping - Rs 4,41,875. This has to be compared with the alternative of the watershed plus approach which can ensure soil moisture for rabi cultivation at a cost of Rs 12,000 per hectare only, apart from social and environmental benefits of communitarian soil and water conservation work.
Thus prima facie it can safely be said that there is neither water nor governance in the Man River basin both with respect to surface and ground water.
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