Rajan Gandhi
In this age of digitization when being online is necessity and not luxury or time pass as such one shudders at the thought of being without smart phone even for one hour, but for people of Doda, Kishtwar, Ramban this winter has turned into a nightmare for several days without electricity and there is no sight of getting it workable for a few more days. This is not the first winter of this 132-KV single circuit Udhampur-Kishtwar- Doda transmission line which had suffered extensive damage at various places on the intervening night of February 6 and 7 due to massive snowfall as per NHPC as a result of which almost whole Chenab Valley plunged into darkness to which electricity is provided through this line only.
As per electrical terms, low voltage less than 1000 volts is used for connection between a residential or small commercial customer and the utility. Medium Voltage is between 1000 volts (1KV) and to about 33 KV used for distribution in urban and rural areas. High Voltage is between 33 KV and about 230 KV, used for sub transmission and transmission of bulk quantities of electric power and connection to very large consumers. Extra High Voltage (Transmission) is over 230 KV up to about 800 KV, used for long distance, very high power transmission and finally Ultra High Voltage – higher than 800 KV. These transmission lines have ‘Width of Right of Way’ which is for 132 KV 27 metres, 220 KV 35 metres, 400 KV 52 metres and all trees within this and immediately adjoining to this are periodically cut to ensure no damage is done to the line in case of high winds or snow fall. Transmission line inspections are carried out either by walking in the terrain or from the air every 1 to 3 years depending upon the SOP of the organization maintaining it. Various issues are observed in the inspections like vegetation in the transmission line area, new structures, excavations, possible inclination of tower structures, condition of steel parts, birds’ nests, woodpecker holes, integrity and condition of insulators and conductors. Special inspections are also carried out whenever necessary particularly for decay damage in towers, earthing, insulators and couplings. Implementation of an integrated vegetation management approach (IVM) is also important part of these transmission lines. The selective removal of tall-growing tree species and the encouragement of low-growing grasses and shrubs is the common approach to vegetation management in transmission line rights-of-way. The original lines were constructed with men or horses to tension conductors and maintenance was largely done by using manual tools. Today, highly specialized power-tensioning equipment is evolved in the process, faults are electronically located, power line patrol by helicopter is a regular procedure in developed countries and maintenance teams are in contact with each other and the system control by radio. For preventive and predictive maintenance of transmission lines most common method applied is monkey method which is manual line patrolling with digital photography of the line components, thermo-graphic scanning for detecting Hot spots. Punctured insulator detection is done by electric field measurement or by voltage measurement method, Corona-Detection by Decor camera, resistance measurement of electric joint in live line condition, tower footing earth resistance measurement is also done. Repairs of deteriorated tower stub is undertaken from time to time since the transmission line towers are working in agricultural fields, mountainous area with regular snowfall and the tower foundation is embedded in ground as such the tower stubs get heavily rusted in life span of about 10-15 years. The major causes for deterioration are wet, marshy soil around tower stubs on account of rain and drain water, watering of crops by cultivators, chemical reaction due to fertilizers and chemicals. Repair process includes cleaning the area around the tower leg, area of one meter wide and one meter deep is excavated around the leg so as to make a room for the process, chimney concrete of the tower stub is broken by vibro hammer, the rusted portion of the stub is thoroughly cleaned using power tools, phospating is done to avoid corrosion and this also helps to get perfect etching and after all this two M.S. angle of the same size as the stub, which are pre-treated in the factory for anti-rusting and notching, are welded with specialized welding procedure. Then the welded surfaces are thoroughly cleaned by MRF cleaning agent and protected from rusting by applying special MRF anticorrosive solution of low viscosity epoxy resin is filled up in the cavity in between old and new stub angles. After this whole joint is sealed by specialized MRF putty to make the surface plain and leak proof and MRF special paint is applied, joint is then wrapped with glass wool, fibre mesh clothing giving extra protection to the stub. In re-concreting process homogeneous jointing of old and new concrete, special bonding agent which is a specific epoxy adhesive is applied over the surface of the old concrete before final concreting is started. Advanced machines like needle vibrator for re-concreting process are used. In the concrete special mesh fibre is mixed which gets uniformly dispersed in the concrete as millions of fibres in every cubic metre. For achieving perfect waterproofing of newly cast sub concrete, special 100 per cent MRF PU paint is applied. The concrete is cured by using a curing catalyst for avoiding excess watering, thereafter concrete portion and the tower leg are painted and finally the remaining pit portion around the concrete is backfilled with soil of compact layers.
The above mentioned procedure is followed worldwide but whether all these preventive measures were adapted by NHPC is million dollar question as damage was not to one or two towers but one tower between Udhampur-Doda and seven towers between Doda-Kishtwar had suffered extensive damages due to snowfall and big trees fell down on the transmission line which under normal circumstances does not happen if line is properly maintained as under maintenance trees will be cut down and towers get repaired/ strengthened. What is more interesting is the fact that 400KV DC (Quad) line carrying power from Dul Hasti to Northern Grid, maintained by Power Grid Corporation, remained intact without any disruption under similar conditions there by clearly indicating that either the tower work of NHPC for this 132 KV (Single Circuit) was not up to standard or the line was not properly maintained. More intriguing is the fact that the 132 KV single circuit Udhampur-Kishtwar transmission line was constructed by NHPC during eighties in order to meet the project requirement in the construction of Dul Hasti Hydroelectric Project in Kishtwar. Since the commissioning of the project in 2007 purpose of this line was over but NHPC has been forced to maintain this line till now as the power transmitted through this line is distributed to Doda and Kishtwar districts. Since 2014 the NHPC has dashed numerous communications to the State Government with the request to take over this line especially when tariff for the power being supplied through this line and consumed by the people in both the districts is being charged by the State Government. As latest as in August, 2018 NHPC Chief Engineer for Dul Hasti project had once again written to the State Government mentioning the urgency for taking over of this line by the JKPDD and he explicitly mentioned that the Head Office of NHPC was not allowing deployment of manpower/ maintenance expenditure for this line which may result into decrease in the reliability of the line in the coming time resulting into disruption of the power supply to Doda and Kishtwar districts. Since commercial operation of Dul Hasti power station on April 7th, 2007, NHPC is providing 12 percent free royalty of power to state as per allocation order issued by GoI which turns out to thousands of crores till now.
As regards WUC (water usage charges), NHPC annually also pays the State Government around Rs 100 crores for Dul Hasti HEP. But despite so much financial benefit from Dul Hasti HEP, however, till date no decision has been taken to take over this line by the State Government for the reasons better known to the PDD. Even more disturbing is the fact that agreement file of NHPC and state Government is not traceable despite a task force employed as such seriousness and callous attitude of State Government is obvious. Similarly work on alternative Batote-Thathri-Kishtwar transmission line started but stopped as the project executing company has gone in for arbitration against the decision of Finance Department which had refused to permit cost escalation as projected by the company. As per department they are trying to convince the arbitrator to allow them to restart the work on the abandoned line so that power supply related issue of Doda and Kishtwar districts gets resolved once and for all but on ground there is no progress.
Notwithstanding the immense difficulties being faced by the people of Chenab Valley, neither any decision has been taken on takeover of Udhampur-Kisthwar transmission line by the PDD as desired by the NHPC from time to time nor work could be restarted on the alternate Batote-Thathri-Kishtwar transmission line whose fate is hanging in balance for past several years. But as is the case with every project of our state no planning, no accountability with the result inordinate delays, no urgency to resolve the issues and the most important lack of political will to get things done.
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