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Tuesday, September 21, 2010

Small Dams VS Big Dams


Small Dams

It appears non-professionals have advised the President to build small dams, as big dams are controversial. This is not so. All big dams are not controversial, like Kalabagh Dam. The President may please get opinion from expert water resources engineers. Small dams do not serve our purpose, as they do not meet our requirements of huge power generation to end load shedding, control super floods to avoid devastation, and provide irrigation facilities to large new barren areas to feed the rapidly growing population. Moreover, small dams are short lived due to silting and cannot serve the said purpose. Small dams rapidly lose storage water due to evaporation and seepage. However, vegetable can be grown from its small quantity of water.

Small dams serve the purpose of drinking water. Small dams are useful as watershed management infrastructure to control soil erosion and stop silt flow. The capital cost of small dam is very high viz-a-viz its storage capacity, lifespan, and service value. Maintenance of small dam is costly. Small dams can never replace big dams. The function and purpose of small dams and big dams are different. About 1000 small dams are not equivalent to one big dam like Basha in service value besides its power generation and flood control capabilities. Small dams are part of water management for big dams. Small dams are no replacement for big dams. Big dams are unavoidable. It is wrong that all big dams are controversial.

Big Dams

Pakistan direly needs big dams to control super floods and avoid death and destruction as experienced this year. Pakistan needs big dams to generate cheap hydropower in large quantities to end crippling load shedding. Moreover, big dams are environment friendly as they turn desert areas into green fields and forests can be raised by the use of water from big dams.  Pakistan needs big dams to create huge storage for supporting the present irrigated areas and for irrigating large barren areas to produce food for the rapidly growing population. Pakistan needs big dams to implement Water Accord paras 2, 4, 6, and para 14 (e) to avoid inter-provincial water disputes. Water Accord could not be implemented for the last 19 years as no big dam was built. Pakistan needs big dams to conserve floodwater, going waste to sea each year. In the event of drought, the storage from big dams provide water for crops

Pakistan needs big dams to replace 6.6 maf of storage lost due to silting at Tarbela and Mangla Reservoirs. Big dams are multipurpose and very cheap and give best service value as compared to the service value of small dams. Big dams regulate river flow, ensure irrigation water to large area, control super floods, and supply water for industrial and domestic uses. Big dams have long lifespan and great service value. Big dams bring economic prosperity and provide jobs for large number of people.

 Big dams run industries from its power generation. The present devastating flood that ruined nearly 25% of Pakistan teaches a lesson to go for big dams. Super floods can only be controlled by big dams. Pakistan needs big dams to replace storage lost due to silting under the Indus Waters Treaty. Pakistan needs big dams to produce hydropower. Water and power are natural resources on a river. These resources must be exploited by building big dams.  Big dams lay the foundation of strong economy and prosperity. Global warming, climate change and glacier melting need big dams to avoid catastrophes due to super floods.
     
Kalabagh Dam created wrong impression that big dams are controversial
                          
WAPDA created Kalabagh Dam controversy and long status quo for 46 years (36+10)=46 due to the selection of wrong dam site on the Indus. Besides this, WAPDA gave tailored TOR to the Project Consultants to achieve specific purpose of the left bank canal from a higher level for irrigating areas in Punjab. Moreover, Kalabagh Dam site has the poorest capacity-inflow ratio in the entire length of the Indus. Because of the poorest CI ratio, the reservoir will silt up with in 20 years. Besides this, silt will be deposited upstream of the Attock gorge that will create unacceptable backwater flow and flooding in Kabul River that will destroy Peshawar valley.

 The KBD Consultants advised WAPDA to build 100 flood days unrestricted low-level sluicing hydraulic structure like a barrage. On the contrary, WAPDA insisted for a wrong hydraulic design to provide 50 floods restricted mid-level sluicing hydraulic structure to build 260 feet high dam. This will create rapid and heavy sediment deposition upstream of the Attock gorge and unacceptable backwater flow and flooding in Kabul River.

Big dams are the symbol of prosperity and economic development. Unfortunately, Kalabagh Dam created great fear in the province of Sindh because of the dam’s location to divert water from a higher level for specific purpose by Punjab. Punjab wants to take off a high level canal, 170 miles long on the left bank with a discharge of 15,000 cusecs to feed Mangla system.

The province of KP has shown fear that with the construction of Kalabagh Dam, Peshawar valley will be ruined by inundation due to backwater flow and flooding in Kabul River. The proof of inundation and ruination lie in the present flood devastation even without the dam.

 With the Kalabagh dam, that is lying on the down of Attock gorge, devastation would multiply. Kalabagh Dam recommended by the Project Consultants is run-of-the-river dam like a barrage. It therefore will not store water during floods. It therefore cannot give protection against super floods even to the downstream areas. Similarly, if WAPDA’s design of 50 floods restricted mid-level sluicing is followed, then Kalabagh Dam will be on run-of-the-river for 50 flood days. In any case, Kalabagh Dam will create sever backwater flow and flooding in Peshawar valley.

 After Kalabagh Dam, the flooding and inundation in Peshawar valley will be aggravated. Kalabagh Dam has become politically controversial due to hidden reason. For this reason, its feasibility report was kept secret from KP. It was declared as classified document. 

WAPDA should have asked the Consultants in the TOR to select the best multipurpose dam site on the Indus with long life span to give best service value.

WAPDA and Punjab determined to build Kalabagh Dam at all cost. WAPDA stopped searching excellent dam sites with best service value and long lifespan like Katzarah and Basha on the Indus and Guroh Dop on Punjkore/Swat Rivers. This resulted in crippling load shedding for long time with no relief. This also created inter-provincial water dispute due to scarcity of water as no dam is built to store floodwater that goes waste to sea each year.

Besides all this, the Kalabagh Dam Consultants stated that the foundation of the dam site is weak, therefore a hydraulic structure more than 160 feet high cannot be built at this site. On the contrary, WAPDA instructed the Consultants under the TOR to build 260 feet high dam.

Similarly, the power generation from the dam due to its wrong hydraulic design is only 1450 MW. WAPDA therefore instructed the Consultants to provide 2000 MW Thermal Power Plant to support low hydropower.

I may inform that all the big dams have no problem like Kalabagh. The Kalabagh Dam became politically controversial for its wrong site and wrong design. Moreover, it was being built for a specific objective.

Besides this, Kalabagh Dam is infeasible in view of the findings of the Kalabagh Project Consultants. Please refer to the feasibility report to verify these facts. No body seems to have read the 27 volumes of the Kalabagh Project report.

In the end, I strongly recommend to build Katzarah Dam, Basha Dam, Guroh Dop Dam and Kalam Dam without loss of further time. None of these dams are controversial. The building of these dams is vital because similar devastating super flood are predicted any time due to global warming, glacier melting and climate change. This time we must avoid similar devastation.

 Land compensation must immediately be paid to those who are displaced by the construction of big dam. Late payment creates problems. China rehabilitated 2.2 million people displaced by Three Gorges Dam well in time. There was no problem. We must follow this practice.

  Unfortunately, WAPDA declared to build Munda Dam with live storage capacity of 0.67 maf that is basically a power dam. The same dam with the same data is now declared as flood control. Chairman WAPDA stated that it will protect Nowshera and Charsadda from super floods. This is all ridiculous. A nominal storage of 0.67 maf cannot protect Peshawar valley where Kabul River was running a flood flow of 400,000 cusecs.    

Besides the above, please pay attention to the lurking catastrophes of water issue of Pakistan. These water issues are given in my website,  fatehuk blogspot.com              

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