There is massive surface water wastage of about 50 maf due to seepage in our 150 years old, highly wasteful, incompatible supplied-based canal irrigation system therefore, there is dire need to avoid it by Integrated Comprehensive Water Management. The total estimated figure of surface water wastage from major sources is about 82 maf out of 142 maf. The major waste flows are from the wasteful supplied-based canal irrigation system, the floodwater waste flow to sea and the loss of water in the wide waterway of the Indus River
Besides the colossal wastage of about 82 maf of surface water from all sources, there would be another enormous wastage of surface water between, 35% to 40% of the 142 maf due to global warming and glacier melting. Assuming only 35% shortage due to global warming, it comes to (142x35%) = 50 maf. This huge shortage of water would be in the second permanent phase of the global warming after about 30 years. There is therefore life saving need to counteract the 50 maf of the surface water reduced flow due to global warming by reducing the existing losses of 82 maf of water wastage from the obsolete supply-based canal irrigation system and floodwater wastage to sea. Besides the above water wastage, the water losses in the 14 miles wide and meandering Indus River Indus is about 6 to 7 maf. The net loss of water in the Indus River Indus River Indus River waterway, the water shares of Sindh and Baluchistan can be diverted from Chashma barrage on the Indus via Sibi in Kachi plain to enter Sindh province. This diversion is possible by lined canal with gravity flow through the proposed All Pakistan Grand Canal supported by Katzarah Dam.
The only way to counteract water shortage due to global warming for the survival of irrigated agriculture in the Indus Basin
"Integrated Comprehensive Water Management is defined as the integral process of watershed management, storage, diversion, conveyance, regulation, measurement, distribution and application of the rational amount of water at proper time and removal of excess water from the farm to promote increased production economically in conjunction with improvement of agriculture practices and institutional arrangement".
In view of the above definition the basic water saving components of water management are:
Storage Dams
The construction of long life storage dam is vital part of water management to conserve, regulate river flow, control and store super-floods and generate cheap hydropower for the use of sprinkler and drip irrigation methods. Storage dams control silt and act as watershed management infrastructure. Silt free water is a great advantage for the use of drip and sprinkler irrigation methods that can irrigate about two to three times more area than with flood irrigation. The support from storage dam is a must for the demand-based canal irrigation system as it releases regulated water supplies as and when required in proper doses. It can provide water to crops on the crop consumptive use basis in time in proper doses for maximum yield. The present Warabandi system of the supply of water, for fixed time duration, on area basis, is obsolete.
Demand-based irrigation system
Demand-based canal irrigation system is the basic and vital component of water management to avoid most of the water wastage from the wasteful supply-based canal irrigation system. Therefore, the incompatible, obsolete, highly wasteful, 150 years old supply-based canal irrigation system needs immediate replacement. The demand-based canal irrigation system would result in colossal saving of about 50 maf of surface water. The supply-based is the most efficient water conveyance system to supply water to crops in time for maximum yield.
The adoption of modern irrigation practices is must for agricultural development using sprinklers and drip irrigation methods. Land reform and land consolidation is essential. Plot of land for irrigation should be given geometrical shapes. All these processes are vital part of ICWM. Sprinklers and drip irrigation methods if practiced can irrigate nearly three times the area than by flooding method. It will remove scarcity of water to be caused by global warming and meet food needs.
Replacing water courses by pipe supply
Traditional watercourses should be replaced by pipe supply as far as possible. This saves seepage and evaporation losses besides theft of water and is an important water saving component of water management. Hydropower generation to run sprinkler and drip system is the vital instrument in the processes of ICWM.
Drainage of irrigated land
The Drainage system for irrigated agriculture is an integral and very vital component of water management in irrigation practice. This is missing in the Indus basin irrigation system since 150 years to evacuate the injurious saline effluent out of the area and control water logging. As a result, drainage effluent has accumulated as groundwater. Moreover, natural surface drains are also blocked due to encroachments violating the Canal and Drainage Act 1887. No surface and subsurface tile drainage is provided to evacuate injurious salinity, control water logging and maintain salt and water balance. Drainage is the missing part of irrigation and is direly vital to keep water table under control and keep irrigated land healthy. As a consequence of no surface and sub-surface drainage system, about 60% of irrigated lands in the Indus basin suffer due to salinity, sodicity and water logging to various degrees. Crop yield on this account is low, and is seriously affected. The right type of drainage system is extremely vital to evacuate injurious saline effluent out of the area, control water table, reclaim land and keep salt and water balance for optimum crop yield otherwise precious fresh surface water is wasted on diseased land. SCARPs and NDP were wrongly conceived mega drainage projects thereby both projects have not only failed but added more salinity and sodicity in soil. As a consequence of drainage accumulation and its misuse, Punjab is pumping about 45 maf of injurious saline groundwater drainage effluent for irrigation use that destroys its land invisibly without the farmers knowing it. The farmers have installed about 10,000 small tube wells that inject about 250 million tons of injurious salts from the groundwater drainage effluent. It is estimated that if this practice of using saline groundwater drainage effluent continue, the Indus basin would turn as saline waste by the year about 2040. Therefore, tile drainage must be provided as it is the vital part of ICWM and integral component of irrigation.
Warabandi System
Warabandi system of 1887 for the supply of water has become obsolete as under the supply-based canal irrigation system it supplies water to crops on land area basis and fixed time limit. This is to be replaced by crop consumptive use of water as and when required in proper doses under the demand-based irrigation system supported by long life storage dam. It will produce maximum crop yield per acre. The farm-to-market-roads and all other agricultural inputs are among the vital processes of ICWM.
The water saving role of ICWM would counteract, the reduced flow caused by global warming
The major sources of water wastage are the 150 years old, obsolete, incompatible supply- based canal irrigation system where about 100 to 105 maf of surface water is diverted in canal system out of 142 maf of the available surface water. About 50 maf of water is wasted due to seepage from the supply-based canal irrigation system. The next major source of water wastage is 25 maf to 35 maf of floodwater waste that goes to sea during monsoon. Besides this, about 7 maf of water is lost in the bed of the Indus River that needs channelizing to save water. The total water wastage on these three counts comes to about (50+25+7)=82 maf out of 142 maf of water. What a great water wastage due to utter mismanagement of precious water? Still no one is concerned.
In the first phase of global warming in about 40 years from now, there would be increased river flows due to glacier melting often resulting in super floods. In the second, and final phase of global warming, there would be 35% to 40% reduced surface water flows on permanent basis. On this account the loss of surface water due to global warming comes to about (assuming only 35% loss) as (142x35%)=50 maf of water. Besides this, hydropower generation from storage dams would also be reduced by the same amount. Therefore, maximum number of dams should be built.
There is already about 82 maf of surface water wastage. The global warming would cause another about 50 maf of water loss as reduced surface flow. There is therefore an extremely compelling need to save and minimize the current water wastage of about 82 maf by ICWM as explained above. This is the only way to negate the adverse effects of water shortage caused by global warming. If ICWM is not implemented, the irrigation system in the Indus Basin would almost have no water as (82+50) = 132 maf of water would be lost out of 142 maf.
It is estimated that the ICWM if implemented would reduce the current water wastage in the canal system by about 50 maf, from floods by 25 maf that comes to about 50+25 =75 maf. Now the situation is that on the one hand, there is loss of 50 maf of surface water due to reduce flow on account of global warming but on the other hand there is golden opportunity to save at least 75 maf of surface water through ICWM.
Therefore, ICWM with all its vital components must be planned right now for immediate implementation as it would require at least 30 years for completion. If ICWM is delayed or avoided the Indus basin irrigated agriculture would completely be ruined. It would not be possible to feed the 32 crores of population by the year 2030. Famine conditions would prevail with food riots and economy destroyed.
Destructive effects of global warming
Some of the destructive effects of global warming on environment are narrated to know the great incoming calamities falling on earth affecting its entire population with sever effects on developing countries. Pakistan would suffer the most due to its location on earth for severe water shortage Desert conditions may prevail.
In fact, human activities, growing population and increased emission of carbon dioxide is mainly responsible for global warming. The world is going to witness climbing temperatures, rising seas, heat wave, heavy precipitation, water scarcity, catastrophic floods, avalanches, tropical storms, earthquakes, tsunami, droughts and food riots besides population movement, pollution and natural disasters. Global warming could result in hurricanes and tornadoes. The increasing use of fuel fossil is causing warmer weather and more chaotic. Rapid deforestation in Pakistan and Afghanistan is contributing to global warming. The use of dirty weapons in war is affecting environment. The global warming is affecting flora and fauna besides species loss. It has created eco-environmental problems. Crops, fruit, vegetables and flowers are losing flavour, sweetness and fragrance. The biological clock of plants and animals is running ahead of time. It is affecting human physiology and would cause infectious diseases. The planet earth and its environment would be under going great change due to multiple calamities as pointed out above. The UN must take serious notice of the horrible global calamities that endangers all life form including human existence on earth. Pakistan needs serious attention of the UN for assistance to implement ICWM.
Environment friendly activities
The Government of Pakistan may immediately enforce environment friendly activities in all fields. The storage of water by dams and reservoirs on all rivers and their by products are all environment friendly measures. Dams and Reservoirs remove water scarcity, control super floods, control silt to act as watershed management infrastructure to increase life of reservoirs, provide drinking water and avoid drought and famine besides producing environment friendly hydropower. More over, storage water is used for irrigation to produce food, raise trees and forests to reduce carbon-dioxide emission and help prevent global warming. In the first phase of global warming, the increased river flow would increase sediment flow that would rapidly silt up reservoir. Therefore, long life reservoirs must be planned. The dire need is to reduce carbon-dioxide emission and control pollution.
President's role
The implementation of ICWM, the building of 35 maf Katzarah Dam and the 8.5 maf Guroh Dop Dam, to counteract shortage of water due to global warming, has to be ordered by the President of Pakistan on war footing. This is because bureaucracy is inert to fight national calamities in time therefore, they wait for the President's order to initiate action. This inert attitude to fight global calamity needs revolutionary change otherwise the future is doomed. The vital water issues are not discussed in the Parliament though the country would face do or die situation in the near future. The consequences of global warming would be far more dramatic than we can imagine.
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