Monday, July 01, 2013

Gujarat CM advisor's strong rejoinder to Dr Kane: Smaller Kalpasar is more viable and is less costly

By Babubhai Navalawala*
Dr Anil Kane has made certain comments on Kalpasar Project and Bhadbhut barrage as published in  (June 16, 2013). His comments are no doubt based on the information/status as per the pre-feasibility studies carried out during 1996-98 by M/S Haskoning and Six Specific Studies by International and National Consultants in the year 1999 for Kalpasar Project. Thus, first of all, it needs to be considered in the light of the updated status of the information. Accordingly, the status of each of the points made is as under.

Origin and evolution of Gulf of Khambhat Development Project 
As can be seen from the Gujarat State Gazetteers, Bhavnagar District (1969) under Chapter (4) “Agriculture and Irrigation” the concept of Gulf of Khambhat Development project was first conceived as back as in 1955 as “Bhal Reclamation Scheme” to prevent sea water flooding and preserve fresh water. The project envisaged the construction of 25 miles long earthen dam and 10000 ft long waste weir.
In 1962, Bhogilal Shah (ex-MP Rajya Sabha, 1952-56) suggested a dam (along with naming the reservoir thus formed as Gandhisar) across the Gulf of Khambhat . This idea of Bhogilal Shah was carried forward by Dr Vithubhai J. Patel who was an eminent earthen dam design engineer of international repute. Dr Vithubhai Patel was the person who named this project as Kalpasar and also visualized/conceived the scope of this project alongwith mentioning various components like fresh water reservoir, irrigation, port development, tidal power generation and industrial water supply as well as suggested to set up various autonomous authorities to manage the complex project. Since then, this project name i.e. Kalpasar has continued to be used by one and all, including Dr Anil Kane, who was associated at some point of time.
In 1975, Prof E M Wilson, Tidal Power Expert who was on a UNDP Technical Cooperation Mission in India, had undertaken preliminary examination of techno-economic feasibility for developing tidal power project in Kutch, Khambhat, Durgaduani Belladonna river and Pitts Creeks (Sundarbans area), West Bengal.
In 1986, Pratap Shah, ex-MLA and the then managing editor, Saurashtra Samachar, Bhavnagar, suggested to construct an embankment dam across Gulf of Khambhat linking Gundala village (West Bank) and Devla village (East Bank) for storing fresh water behind the proposed embankment structure to solve the water scarcity problem of the Saurashtra region. Considering the views of Shri Pratap Shah, the Central Designs Organization (CDO), Government of Gujarat, prepared a proposal of constructing an embankment dam across the Gulf of Cambay.
In 1988, the Government of Gujarat got the Reconnaissance Study carried out through M/s Haskoning & Associates, Netherlands. The study considered the development scenarios of tidal power production, fresh water storage and a combination of both. For dam construction, the alignment between Ghogha on the western bank and the Narmada river mouth on the eastern bank was considered. The report concluded that the project is potentially viable but it is required to carry out the pre-feasibility study to firm up the dam alignment and other project features as well as alternative alignment north of Bhavnagar and evaluation of smaller scale schemes. Therefore, the concept of Khambhat Gulf Development has been under the continuous process of refinement from “Gandhisar” to “Kalpasar” during last four decades and, as such, no individual is entitled to claim to be the person who perceived this project.
In 1995, the Government of Gujarat took the decision to take up the Pre-feasibility Study. Accordingly during the period from 1996 to 1998, M/S Haskoning carried out preliminary field survey and investigations with alternative alignments, tentative designs of the project components including hydrology, foundation studies, dam design, construction methodology, cost estimates. The Pre-feasibility Study established the technical viability of the Gulf of Khambhat Development Project and led to recommendation for the preparation of feasibility project report. It was also recommended to carry out intermediate studies on six selected aspects such as integration of Gulf of Khambhat Development Project’s benefits with other projects, morphology of estuary, tidal power, salt balance in the reservoir and adjacent area, drainage condition and pollution control.
In 1999, the Government of Gujarat took up Six Specific Studies as suggested in the Pre-feasibility Report. The report concluded that the project is technically feasible and economically viable. The specific studies further recommended to carry out detailed bathymetric, geophysical and geotechnical investigations both in the Gulf and more particularly in the Narmada river mouth. It was, nevertheless, emphasized that much greater degree of site investigation and data collection would be necessary to allow unqualified conclusions to be reached on the technical adequacy.
In 2000, after acceptance of the Six Specific Study report, the Government decided to go ahead with preparation of feasibility report. For this purpose, the Kalpasar Department was created in May-2003. Further, the Expert Advisory Group was constituted in December-2003 to advise the Department on various technical issues. Till 2012, EAG has held nine meetings and has advised the Department on number of technical issues which has helped in determining various studies and technical parameters relating to this project. 

Hydrology of the Project
According to Dr Anil Kane, ample flood water from Narmada river would have been available to Kalpasar reservoir in case the dam alignment had been finalised, as per the pre-feasibility report i.e. Narmada river directly draining in to Kalpasar reservoir. In this context, first of all, it is to be understood/ appreciated that the availability of Narmada river waters for Gujarat is governed by the NWDT award. Therefore it should not be assumed that entire quantity of water flowing in Narmada river is available to Gujarat only. NWDT has assessed (at 75 % dependability) 28.00 MAF (million acre feet) of water in the basin (Clause II of NWDT award). Total available water (i.e. 28 MAF) has been allocated among the party states i.e. MP (18.25 MAF), Gujarat (9.00 MAF), Maharashtra (0.25 MAF) and Rajasthan (0.50 MAF).
Further, it is also to be understood that water availability and flood events are altogether different. Water Availability study is for dependable flow whereas flood study is for maximum flood for which dam is to be designed. As per data available from Sardar Sarovar Narmada Nigam Ltd. (SSNNL), water available from Sardar Sarovar dam by way of spillage & releases from RBPH will be occasional & it will be during surplus (good) year after Stage-3 of development taking place in the basin. The spill-water is required to be shared among the party states as directed in the Clause IV (5) of NWDT awards which is as follows:
“It may be mentioned that in many years there will be surplus water in the filling period after meeting the storage requirements and withdrawals during the period. This will flow down to sea. Only a portion of it will be utilizable for generating power at Sardar Sarovar river-bed power house, and the rest will go waste. It is desirable that water, which would go waste without even generating power at the last river-bed power-house, should be allowed to be utilized by the party States to the extent they can.
“Gujarat is, therefore, directed that whenever water starts going waste to sea without generating power, or based on the information received from upstream gauging stations, it anticipates that water would so go waste, it shall inform the Narmada Control Authority (hereinafter referred to as the Authority) and designated representatives of all the concerned States. Gujarat shall also inform them when such flows cease. During the period of such flows, the party States, whose reservoirs are spilling and the spill water cannot be stored elsewhere, may utilize such flows from the said reservoirs as they like.”

Also, SSNNL has made the provision to draw additional water to the tune of 3 MAF (over and above 9.0 MAF) for Saurashtra, Kutch and North Gujarat. In view of above, water available downstream of the Sardar Sarovar dam during normal/deficit year will be occasional, i.e. during surplus year only after deducting the drawl of additional water by SSNNL. Contrary to this factual position, Dr Kane has assumed that entire design flood occurring in river Narmada to be available for Kalpasar. Further, since number of projects have been and/or planned to be constructed in the Narmada basin, the volume & peak value of the flood, in certain conditions, would get reduced and duration of spill from Sardar Sarovar dam will increase, which will help in diverting water from Narmada Diversion Canal for longer period.
The Narmada Diversion Canal (NDC) is planned to divert water from Bhadbhut reservoir to Kalpasar reservoir with carrying capacity of 100,000 cusecs. If NDC runs at full capacity, then 250 Mm3 per day water can be diverted through NDC. The NDC can divert 2500 Mm3 and 7500 Mm3 of water if it runs for 10 days and 30 days respectively in the monsoon. Utilizing data up to the year 2006, the water availability from Narmada river has been recently worked out by the Central Design Organization and this has been duly vetted by National Institute of Hydrology (NIH), Roorkee. Accordingly, water availability is 5,683 MCM at 50% dependability at Bhadbhut barrage site. The water availability assessed by M/S Haskoning was 6016 MCM for Narmada Stage-3 condition but utilizing data upto 1992. Thus, shifting the dam alignment has no impact/effect on the water availability for Kalpasar reservoir. This hydrological phenomenon would be easily appreciated and understood by a person who has even rudimentary understanding of the hydrology.

Siltation study
According to specific studies carried out in 1999, about 70% silt load in the proposed Kalpasar reservoir would be due to Narmada river alone and the life of the project was estimated at 250 years for the Kalpasar Project inclusive of Narmada river as was indicated in pre-feasibility report. Due to shifting the alignment northward by 15 km, the silt load from Narmada river will get substantially reduced (and consequently, the reduction in total volume of Kalpasar reservoir siltation) due to which the estimated life of the project would enhance to 450 years. Thus, the change in the alignment is beneficial for Kalpasar Project.

Geotectonic vs foundation conditions in the Gulf of Khambhat
Geotectonically, the Gulf of Khambhat is a Graben i.e. a sunken block where basalt / granite is met with at a depth of 2000 m (6560 ft) to 2500 m (8200 ft) below the sea bed. This is corroborated by the drilling operations carried out in the Khambhat Gulf area by the ONGC up to a depth of about 2500 m below the sea bed. The ONGC drilling has established the presence of thick pile of sand and clay up to about 500 m below the sea bed. Underneath this 500 m thick soft alluvial deposit, there are weak and soft layers of sand rock, limestone and shale up to 1500 m.
During prefeasibility stage, M/S Haskoning had drilled 10 bore holes, each of 30 m depth, to evaluate the foundation conditions. The results revealed that the sub strata below sea bed upto the drilled depth consist of fine sand and silt having very poor bearing capacity. Especially in the Narmada river mouth where spillway was proposed, the substrata are weak consisting of sand inter layered with clay which is totally unsuitable for heavy concrete spillway structure. Moreover Narmada-Son fault which is seismogenic (i.e. prone to seismicity) passes very close to Narmada river mouth.
Further Dr Kane has proposed a kilometer long under water tunnel about 25 m deep to allow non-stop traffic movement. One wonders how in the loose alluvial formation of 500 m thickness under sea bed, traffic tunnel could at all be possible. Under water tunnels are known but they have been constructed through rocky formations. With this kind of Geotechnical conditions, neither any massive structure and nor a tunnel below the sea bed can be constructed. Considering all these factors and as recommended by the Expert Group on ‘Geotechnical Investigation and Seismic Studies’, the Government has decided to shift the Kalpasar Dam alignment further north by 15 km.

Advantages of the shifting of dam alignment 
The shifting of dam alignment northward along with diversion of Narmada water through barrage with canal offers a preferred option so as to reduce the cost of the project in addition to enabling better control of flood flows and sedimentation and making the excavated soil material available for dam construction, due to which it would help avoid environmental repercussions in the Narmada estuary. It would be pertinent to point out here that ecologically, an estuary is considered to be “highly sensitive” and as such, its submergence (due to the alignment as referred by Dr. Kane) would prove to be a major/serious hurdle in obtaining the statutory environmental clearance from the competent authority.
In the case of the shifted Kalpasar Dam Alignment, i.e. Alignment No V (i.e. shifted by 15 km northward), existing Dahej and Bhavnagar ports are kept out of the dam enclosure and as such, their sustainability will increase and they would not face any hindrance in their functioning and development. Moreover, the sustainability of fresh water status of the reservoir would also increase. According to the National Institute of Oceanography, Panaji, Goa (under Government of India), the port locations on downstream of the dam would have the benefits of improved draft availability due to rise in tide level, decrease in current speed and substantial reduction in sediment concentration.
Dam Alignment No V would enable the creation of an appropriately sized fresh water reservoir which would have sufficient storage capacity about 10,000 Mm3 as well as absorb reasonably enough chance flood waters.
Alignment No V with Narmada water diversion through barrage-cum-canal system will have the anticipated benefits of lower cost, avoidance of constructional complexity, non-interference to the functioning, improved prospects of development of Dahej Port and, as a result of all these, better techno-economic viability of the project as a whole as compared to the one as per Alternative No I (Ghogha-Dahej-Hansot) of dam alignment.
The major factor for the consideration of Alignment No I (Ghogha-Dahej-Hansot) was the installation of tidal power blocks in the existing four deep channels. In the case of the tidal power component being delinked, avoidance of deep channels becomes a preferred option from the view point of overall viability of this project.
Under the Alignment No V, the barrier structure is envisaged to be mainly an earthen and/or rock-fill dam for which the alluvial foundation material would not form a major constraint for construction.

Tidal power generation
In six specific studies, it was estimated to generate tidal power of 1580 MW with double basin system for continuous power and 5880 MW for single basin on the basis of study done for the Severn Barrage Tidal Project in U.K. who had planned for tidal power generation with almost the same magnitude as broadly expected for Kalpasar Project. But, UK Government has recently shelved this project of 9000 MW installed capacity, giving reasons that wind and nuclear power are cheaper than tidal power. In this connection, it will be worth to know the global experience so far. Nowhere, in the world, tidal power project having magnitude (5880 MW) (as estimated in case of Kalpasar project) has so far been executed. Moreover, there is no project of this magnitude in the world where tidal power reservoir and fresh water reservoir are juxtaposed and that too in alluvial formation. Few tidal power projects with very small installed capacity are presently run on experimental basis as indicated below.
Capacity installed (MW)
Max. Tidal range (m)
Year of commissioning
La Rance
Kislaya Gulf
Small scale
Pilot project
Experimental plan
Experimental plan
However, it is to point out herein that there is a scope of independent tidal power generation scheme in Kachchh for which the Central Electricity Authority has already prepared the Project Report for generating 900 MW tidal power.

Reasons for delinking of tidal power components
Water resource development was the prime driving force in the evolution of the project. Tidal power development was to be complementary resource component. Creation of saline tidal basin on the Saurashtra side would aggravate ground water salinity ingress in the coastal area, besides depriving the benefits of land recovery, reclamation and development for value-addition based utilization. Combination of saline tidal power basin with fresh water reservoir could be a threat to sustainability of quality of fresh water of the proposed reservoir. The share of the tidal power component in the total cost of Kalpasar Project comes to 65%. Further, the production cost of tidal power would be substantially higher than any other kind of the power projects like hydro power, thermal power, wind energy and solar energy.
With weak foundation material permeated by several fault lines at the site, the concrete tidal power dam blocks will face the serious problem of the most unsuitable foundation conditions besides rendering it to be very much prone to high earthquake risk.As of now, there is no experience in the world of manufacturing massive caissons of 60,000 to 100,000 tonnes weight as would be required for construction of tidal power dam blocks for such situations.

Consultation with business houses
In the year 2008, the Kalpasar Department had held “interactive” discussions with Adani Group (March 25), Jay Prakash Associates (March 25), Hindustan Construction Co (March 27) GVK power Co. (April 3), L&T Ltd. (April 4) and Essar Group (April 6), who are national level reputed companies involved in development of infra structures in India, to seek their views and suggestions for implementation of Kalpasar project with and without tidal power component. All of them recommended to go for wind power rather than tidal power due to requirement of massive investment and comparatively very high production cost as well as enormous complexity in construction of massive caissons for tidal power components. The planned scope of Kalpasar Project, now, includes the wind and solar power generation components.
* The Gujarat chief minister’s water resources advisor, former secretary, water resources, Government of India

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