Drainage System And Water
Drainage System And Water
- The flow of water through well-defined channels is called as drainage. An integrated network of main river and its tributaries is called drainage system or river system. Generally, the area drained by a river or river system is called as its river basin or catchment area or watershed. Though there are subtle differences among them. The catchment area of large rivers or river system is called river basin while those of small rivers, a lake, a tank is often referred as watershed. Watersheds are small in area, generally less than 1000 ha. On the other hand, water divides are hills and ridges that separate the adjacent watersheds or river basins e.g. the Sahyadris.
- A river basin or watershed is often taken as planning unit for macro/micro level development planning because 1) A river basin is marked by synergy and unity. Events in one part of the basin (e.g. flood, drought etc.) affect the other parts as well. 2) The data about land and water characteristics is measurable and comparable.
- Drainage pattern is the design formed by arrangement of river and its tributaries. The dendritic pattern, the most common one, looks like a tree and its branches. It develops in the regions having uniform rock structures with insignificant joints and faults e.g. Ganga, Godavari rivers’ pattern. In trellis pattern, primary tributaries flow parallel while secondary tributaries join from side e.g. Drainage in Himalayan Mountains. In radial drainage pattern, rivers radiate centrifugally from a hill e.g. Chhota Nagpur plateau. In peninsular India, rivers flow in faults and fractures of rocks often at right angles to show rectangular pattern. Thar Desert having centripetal drainage shows rivers flowing into central depression or lake.
- The study of drainage system is important for understanding water availability across different regions for agriculture, industries, cities, hydroelectricity projects; interstate and international- water disputes; river linking project, Multipurpose river projects, etc.
RIVER BASINS OF INDIA | Drainage System And Water
- The drainage system of India is an outcome of physiography and rainfall. The surface of India receives average annual rainfall of 118 cm of which only 49% water flows as surface run off into rivers (34% evaporates while 22% seeps into ground). The drainage basins can be classified as follows:
|Size of river basin||Area (km2)||Numbers|
|Medium||2000 – 20,000||44|
- The drainage system of India can be classified as 1) Arabian Sea drainage and Bay of Bengal drainage or as 2) Himalayan and Peninsular drainage and Inland drainage.
HIMALAYAN RIVERS | Drainage System And Water
- The Rivers originating in Himalayan and trans-Himalayan region consists of three river systems namely (1) Indus (2) Ganga and (3) Brahmaputra Systems.
- The Indus and Brahmaputra and their tributaries after originating in the southern slopes of Tibetan highlands, flow parallel to axis of Himalayas and enter the plains by cutting across the ranges through deep gorges. Most of these rivers are antecedent rivers. On entering the plains suddenly the flow becomes sluggish due to decreased gradient, river deposit large amount of detritus brought with them (formed by intense erosive activity in Himalayas) across the vast Great Plains of North India. They develop meanders, oxbow lakes on flat plains. Sometimes they shift their course during floods.
THE INDUS SYSTEM | Drainage System And Water
- The Indus is the westernmost river system in the subcontinent. Of the total 2880 km, 709 km lies in India i.e. a catchment area of 3,21,300 km2 out of 11,65,000 km2. The Indus originates in Bokhar Chu glacier near Mansarovar in northern slopes of Mt. Kailash. It drains largest number of glaciers of Himalayas, Ladakh, Zaskar and Karakoram ranges. In Tibet it is called Singi Khamban (Lion’s mouth). In India it receives river Zaskar below Leh, rivers. Suru, Dras, Shyok, Nubra, Shigar and Gilgit. The river enters into Pakistan after passing through a deep gorge near the hair-pin bend of Nanga Parbat. The Jhelum, Chenab, Ravi, Beas and Satluj are its tributaries in India. The waters of the Indus River System is shared between India and Pakistan through Indus Water Treaty, 1960.
- The Jhelum springs at Verinag South of Srinagar. It flows northward, enters into Wular Lake, and then turns westward through Baramulla, at Muzaffarabad in Pakistan occupied Kashmir it turns southward. River Kishanganga joins on it’s right bank from north side. It is navigable between Anantnag and Baramulla and has Tulbul navigation project near Wular Lake.
- River Chenab flows in India for about 1180 km draining 26,755 km2 area in India. The Chandra and Bhaga, the two main source tributaries of river originate near Bara Lacha Pass in Lahul district of Himachal Pradesh. Their combined flow is then called as Chenab which flows between the Pir Panjal and the Greater Himalayas. The important hydel projects installed across the Chenab are Selal, Dulhasti and the recent Baglihar project in Doda district.
- The Ravi has its source in the Kullu hills near the Rohtang Pass in Himachal Pradesh. It drains the area between Pir Panjal and Dhauladhar. It forms the boundary between India and Pakistan before entering into Pakistan.
- The Beas river too springs near Rohtang Pass. It drains Pir Panjal and Dhauladhar range and meets Satluj River at Harike. It’s the only river in Indus System which flows entirely in Indian Territory.
- The Satluj river rises from Man Sarovar-Rakas Lakes in western Tibet. The river forms deep gorges and canyons in Tibet and Greater Himalayan ranges. It enters India at Shipki La Pass in Himachal Pradesh. The Nathpa-Jhakri is run off the river project on Satluj in Kinnaur district. It is country’s largest hydroelectric power project (1500 MW). Further at Bhakra, country’s tallest straight gravity dam was built. Unfortunately the water storage capacity of its reservoir Gobind Sagar has been drastically reduced due to huge siltation by the youthful Satluj. Further in Punjab a network of canals has been built across the Ravi, Beas and Satluj rivers which have irrigated the otherwise arid lands of Punjab and Haryana.
THE GANGA RIVER SYSTEM | Drainage System And Water
- The Ganga basin accounts for 26.3% of the geographical area of the country. It is shared by ten States. The Ganga originates as Bhagirathi from Gangotri glacier in Uttarkashi district of Uttarakhand. Alaknanda (originating north of Badrinath) joins it at Devprayag. Passing by Rishikesh the Ganga debouches into plains at Haridwar. From Haridwar it flows south and southeast direction to reach at Allahabad. Here it is joined by Yamuna. Many canals flow from Ganga and its tributaries, particularly in UP and Bihar. Further, near Rajmahal hillis, Ganga turns southeast and bifurcates at Farakka into Bhagirathi-Hugli in West Bengal and as Padma in Bangladesh. In Bangladesh, Brahmaputra joins it at Goaludo and after meeting Meghna it enters into the Bay of Bengal. The arcuate shaped delta of Ganga and Brahmaputra is world’s largest delta, 400 km in length. The delta is made up of a web of distributaries and islands and is covered by dense forests called Sundarbans. A major part of the delta is a long-lying swamp which is flooded by marine water during high tide. The Ganga is called Inland Waterway No. 1 from Allahabad to Kolkata and Haldia Port.
- Yamuna is the largest and most important tributary of Ganga. It originates from Yamunotri glacier on the Banderpunch Peak in Garhwal in Uttaranchal. After cutting across Nag Tibba, Masoorie and Shivalik ranges it emerges out of the hilly area and enters plains near Tajewala. It flows southward up to Mathura and then southeastward up to Allahabad where it unites with Ganga. Tons, Hindon, Chambal, Sind, Betwa and Ken are its important tributaries.
- The Chambal rises near Mhow (Southwest of Indore) in Vindhya range in Madhya Pradesh. After passing through Kota and Dholpur in Rajasthan it unites with Yamuna in Etawah district of Uttar Pradesh. Recent geological uplift, poor rainfall and resulting severe erosion have given rise to numerous deep ravines and a badland topography in Chambal basin. Banas, Sind, Betwa and Ken are its important tributaries. The main multipurpose projects built on Chambal are Gandhi Sagar, Rana Pratap Sagar (Rawatbhata) and Jawahar Sagar.
- The Son river springs from Amarkantak plateau north of the origin of Narmada. After draining the Kaimur ranges of Baghelkhand, it meets Ganga in Patna district. Important tributaries are Johilla, Gopad, Rihand, Kanhar and North Koel rivers.
- The Damodar rises in the eastern part of Chhota Nagpur plateau and flows through a rift valley. River Barakar is its largest feeder Damodar meets the Hugli river at Falta. The Damodar valley corporation’s Tilaiya, Maithon, Barakar and Panchet multipurpose projects have transformed this ‘sorrow of Bengal’ into a lifeline of industrial production.
- Among the Himalayan tributaries, the Ramganga originates in Garhwal District of Uttaranchal and joins Ganga at Kannauj in Uttar Pradesh.
- The Kali River or Mahakali rises near Milam glaciers in Nepal Himalayas. It forms boundary between Nepal and Kumaon. It is known as Sarda or Chauka after it reaches the plains near Tanakpur. The pancheshwar dam to control the flow of Kali is proposed MP dam, a joint venture between India and Nepal. The river joins Ghaghra in India.
- The Ghaghra River originates near the Gurla Mundhata peak, south of Man Sarovar Lake in Tibet. It is known as Karnaili in Nepal. It’s important tributaries are the Sarda, the Sarju on the bank of which Ayodhya is located and the Rapti. The Ghaghra joins Ganga at Chhapra in Bihar.
- The Gandak River originates near Tibet-Nepal border and joins Ganga at Hajipur near Patna. The Burhi Gandak River joins Ganga opposite Monghyr town in Bihar.
- The Kosi River consists of seven streams and popularly called as Saptakoshi in Nepal. Arun is its main stream which rises to the north of Gosainthan peak. Soon after debouching on the plain, the river becomes sluggish and large scale deposition of eroded material takes place. The river is braided and shifts its course frequently. This has resulted in frequent devastating floods. Thus the river is often termed as the “Sorrow of Bihar”. In order to tame the river, barrages in upstream course and embankments have been constructed as joint venture of India and Nepal.
THE BRAHMAPUTRA RIVER SYSTEM | Drainage System And Water
- The Brahmaputra rises in the Chemayungdung glacier in the Kailas range of Himalayas. Indus and Satluj rivers too originate from the nearby source of Man Sarovar Lake. With a total length of 2500 km, Brahmaputra is one of the longest rivers of the world. It is known as Tsangpo in Tibet and Yarlung Zangbo in Chinese. In Tibet it flows sluggishly in dry and high altitude terrain (more than 3000 m) of Tibet and is used as navigable waterway. It also forms a spectacular Grand Canyon like Canyon in Tibet. Near Namcha Barwa Mountains, the river takes a sudden south and then southwestward turn to pass through the deep Dihang or Siang gorge of Himalayas. Here initially it is called as Siang and then as the Dihang. The altitude drastically falls from 2450 m north of Namcha Barua to only 135 m at Sadiya where river emerges from the mountains. Here it is joined by Dibang from north and Lohit from the south.
- From Sadiya onwards, the river is known as the Brahmaputra. In Assam valley the Brahmaputra is joined from the north by Subansiri, Kameng, Belsiri, Dhansiri (north), Manas, Sankosh and Tista. From the south Dibru, Burhi, Dihing, Dikhu, Dhansiri (South) and Kalang join the Brahmaputra. The Brahmaputra has braided channel. It carries lot of silt and there is excessive meandering. It forms many river islands of which Majuli is world’s second largest one. With rainfall concentrated during Monsoon months only the river has to carry enormous amount of water and silt which results in disastrous floods in the rainy season and constant shifting of river channel. The Brahmaputra is navigable up to Dibrugarh. It is recognized as National Waterway No. 2.
- The Brahmaputra enters Bangladesh near Dhubri. After joining of Tista it is known as Jamuna. The Jamuna and Ganga Confluence at Goalundo and afterward is called as Padma. Further South, Padma is joined by Meghana (Barak river in India) and thence onward it is known as Meghana to finally merge in Bay of Bengal.
- Barak (Meghana) river rises in Manipur Hills as the Barak river and flows west becoming the Surma river and then flows south as the Meghana river in Bangladesh.
PENINSULAR DRAINAGE SYSTEM | Drainage System And Water
- The peninsular river system is older than Himalayan drainage. It has reached a mature state of development, particularly the lower portions of river valleys. This is characterized by broad and shallow valleys with low gradients presently almost graded profiles. The peninsular rivers are devoid of meanders and have almost fixed courses. Due to lack of snow capped sources they either carry small quantity of water or become dry during summer season.
- The present drainage system of peninsula is shaped by two major geological events in the past. The first was the submergence of western flank of the peninsula leaving just the upper parts of West flowing rivers above sea level and second was the creation of fault troughs of Narmada and Tapi rivers at the time of upheaval of the Himalaya.
- The peninsular river system can be categorized into following sections:
- The Mahanadi, Godavari, Krishna, Kaveri and other rivers draining Southeast into Bay of Bengal.
- The Narmada and Tapi flowing west as well as several smaller streams originating from Western Ghats flow westward into Arabian Sea.
- The tributaries of Ganga and Yamuna like Chambal, Betwa, Ken, Son and Damodar flowing in North-easterly direction.
THE EAST FLOWING RIVERS OF PENINSULA | Drainage System And Water
- The Mahanadi originates in the northern hills of Dandakaranya in Raipur district of Chhattisgarh. Flowing through the Saucer shaped Chhattisgarh Plains and then cutting across the Eastern Ghats the river finally empties itself into Bay of Bengal. It forms delta complex along with Brahmani and Baitarani rivers. It’s main tributaries are lb, Mand, Hasdo and Sheonath on the left bank and the Sandur, Paid, Ong and Tel on the right bank. The Hirakud dam on the river has reduced flood intensity of river.
- The Godavari It is the largest river system of peninsular India with catchment area in Maharashtra, MP, Chattisgarh, Orissa, Andhra Pradesh. The river originates in the Tryambak plateau in Nashik district of Maharashtra. The Penganga, Wardha, Wainganga, lndravati and Sabri are important left bank tributaries while Manjra is the only important left bank tributary. Below Rajamundry in Andhra Pradesh the river splits into several tributaries and merges into Bay of Bengal by forming lobate shaped delta in East Godavari district. The Gangapur, Jaikawadi in Maharashtra and Pochampad in Andhra Pradesh are important dams besides several barrages. A new Polavaram multipurpose project is being constructed in Western Godavari district. The Godavari is navigable up to a distance of 900 km from its mouth. Also there is an extensive canal irrigation-navigation network in deltaic reaches of Godavari as also for other East flowing rivers like Krishna, Kaveri, Penneru Rivers.
- The Krishna: It is the second largest east flowing river in Peninsula. It rises near Mahabaleshwar in Sahyadri. It’s total length is 1400 km. The Koyna, Ghataprabha, Malprabha, Bhima, Tungabhadra, Musi and Muneru are its important tributaries. The Koyna, Tungabhadra and Nagarjunsagar are important dams across Krishna river system. The large delta of Krishna appears to merge with that formed by Godavari.
- The Kaveri: It originates in Taal Kaveri in Brahmgiri hills located in Coorg Plateau of Karnataka. Its total length is about 800 km. The upper catchment area of the river receives summer rainfall due to South-West monsoon while lower catchment area receives rains from retreating north-east monsoon. Thus, its relatively a perennial river and therefore an important source of irrigation and hydroelectricity. In fact 90 to 95 per cent of its irrigation and power production potential is already harnessed.
- The main tributaries of river are the Herangi, Hemavati, Shimsha and Arkavati from the north and the Lakshmntirtha, Kabani, Suvarnavati, Bhavani and Amravati from the South. The river descends from South Karnataka plateau to Tamil Nadu plains through famous Sivasamudram waterfall. The Cauveri has formed quadrilateral delta in Bay of Bengal.
- Among other east flowing rivers of Peninsular India are from north to south, the Subarnarekha, Brahmani, Penneru, Ponnaiyar and Vaigai.
THE WEST FLOWING RIVERS OF PENINSULA | Drainage System And Water
- The west flowing rivers do not form deltas but only estuaries. This is due to the fact that these rivers, especially Narmada and Tapi, flow through hard rocks and are not able to form distributaries before they enter the sea.
- The Narmada is the largest of all the west flowing rivers of peninsula. It rises from Amarkantak plateau in Shandol district of Madhya Pradesh and flows through a rift valley between the Vindhyan Range on the north and Satpura range on the South. It’s total length from the source to the estuary near Bhadoch in Gulf of Khambat is 1310 km. It forms spectacular Dhuandhar Falls near Jabalpur Marble Rocks. There are several islands in the estuary of Narmada of which Aliabet is the largest. The Sardar Sarovar Multipurpose Project on Narmada has been controversial for various reasons. Since the river flows through a narrow valley confined by precipitous hills, it does not have major tributaries with the exception of Hiran river on its right bank.
- The Tapi originates on the Satpura plateau in Betul district of Madhya Pradesh. While passing through the Khandesh plains of Maharashtra, it receives the Puma river on it’s left bank. Further most it crosses the Western Ghats and then alluvial plains of Surat before entering Gulf of Khambhat through an estuary. The Ukai dam on Tapi river provides water for urban and agricultural uses to area around Surat.
- Sabarmati river, the combined stream of Sabar and Hathmati, rises from the hills of Mewar in the Aravalli range. Mahi river rises in the Vindhyas. Both the rivers empty themselves into Gulf of Khambat.
- Although the west flowing rivers of Sahyadri form only about 3% of the areal extent of basins of India, they contain about 18% of the country’s water resources. The important rivers falling in this category, apart from above mentioned ones, are the Ulhas in Mahashtra, Mandovi, Zuari and Rachol in Goa; Kalinadi, Gangavalli-Bedti, Sharavati, Tadri and Netrovati in Karnataka and Beypore, Pannam, Bharatpuzha, Periyar and Pamba in Kerala. Most of the streams flow swiftly down the steep slope. The famous Jog or Gersoppa Falls (289 m) made by Sharavasti river is the highest in India.
INLAND DRAINAGE | Drainage System And Water
- These are seasonal streams in the arid regions of India. The Ghaggar river in Haryana which is supposed to be remnant of proverbial ancient Sarswati river gets lost in dry sands near Hanumangarh in Rajasthan. The Luni river in Rajasthan originates near Ajmer and after flowing through Thar desert gets lost in the Rann of Kachchh. The Aksai Chin region in Ladakh too has some inland drainage.
RIVER REGIME | Drainage System And Water
- The pattern of the seasonal flow of water in a river is called as it’s regime. The main difference in the flow pattern of the Himalayan and the peninsular rivers is caused by the differences in Climate. The Himalayan rivers are perennial and their regimes are dependent on the pattern of water supply both from snowmelt and rainfall. Their regimes are both monsoonal and glacial. The regime of most of the peninsular rivers, on the other hand, are only monsoonal as they are controlled by rainfall alone. The regimes of peninsular rivers even among themselves are not same because of the differences in the seasonal distribution of rainfall in various parts of plateau.
- The discharge is the volume of water flowing in a river measured over time. It is measured either in cusecs (cubit feet per second) or cumecs (cubic meters per second). The Ganga has minimum flow from January to June.
- The maximum flow in Ganga occurs either in July or August. After September there is a steady fall in the flow of Ganga. The river has thus typical monsoon regime, although the Ganga maintains a sizeable flow in early part of summer before beginning of monsoon due to Himalayan Snow melt.
- Also there are striking differences in the river regimes in eastern and western parts of Ganga basin. Ganga can be compared with Jhelum. Jhelum attains its maximum in June or even in May, as it’s flow is mainly caused by the snow melt from the Himalayas. Thus the difference in the river regimes can be compared by variation in maximum and minimum flow of rivers. The mean maximum and minimum flow of Ganga at Farakka are 55000 cusecs and 1300 cusecs respectively. For Jhelum the respective figures are 600 and 50 cusecs.
- Peninsular rivers have markedly different pattern than Himalayan rivers. The Godavari has the minimum discharge in May and the maximum in July-August. After August there is a sharp fall in river flow. The mean maximum flow of Godavari at Polavaram is 3200 cusecs while mean minimum flow is only 50 cusecs.
- The data on water discharge in different rivers in different parts of the year have important implications to their utilization by States. It is on this count that the inter-state water disputes arise.
USABILITY OF RIVERS | Drainage System And Water
- Of the total 37, 00,000 million m3 of annual precipitation, large part seeps into the ground and some part is lost by evaporation and transpiration. The rivers carry 45% of this total precipitation but because of uneven topography and flow characteristics all of it is not usable. And from the above 45%, only 33% of annual flow is available for irrigation. 60% of total river flow is concentrated in Himalayan rivers, 16% in Central Indian Rivers and the rest in the rivers of Deccan Plateaus.
- Large rivers in mountainous regions have great hydroelectricity potential. Dependable power generation from the peninsular rivers requires impounding of water during the monsoon months. The Himalayan rivers do not have such problems as their flow is appreciable even during critical winter months. They however have other problems like difficulty in construction of large storage due to narrow valleys, high siltation, high seismicity of the region and vast alluvial plains with no variation in relief. Overall the country has power potential of 84000 MW at 60% load factor from all rivers.
- The country has navigable waterways of about 10,600 km. The most important navigable rivers are Ganga, Brahmaputra, Mahanadi as well as large lakes and tidal creeks. Withdrawal of large quantities of water for irrigation resulted in dwindling flow in many rivers. Among peninsular rivers Godavari, Krishna, Narmada and Tapi are navigable near their mouths only.
- The rivers also supply water for agriculture, cities, villages and big industries. But unfortunately the quality and quantity of water in rivers is being eroded due to diversion of water from them and flow of sewerage and effluents into the rivers. About 50% of country’s total fish production comes from inland fisheries to which rivers, its canals and reservoirs contribute the most. There is tremendous scope to increase freshwater fish production with improved water quality and quantity in rivers.
SHIFTING COURSES OF RIVERS | Drainage System And Water
- There can be numerous causes responsible for shifting of river courses. These include shifting gentle slope of the Great Plains of India, meandering of rivers, straightening of the river courses during floods, upliftment of Potwar Plateau or down warping of the Malda gap. Both Peninsular and Himalayan rivers have shifting courses, especially in lower reaches. In upper reaches, river capturing by headward erosion of river is the main cause. In plain areas, generally the rivers form meanders in their courses. During floods rivers try to straighten their courses to which we call shifting of river course. This is especially seen in lower Ganga Plains of ‘eastern Uttar Pradesh, Bihar and Bengal. River Kosi and Gandak are notorious for changing their course during floods. The Brahmaputra’s course too has been changed many times in the past. In Punjab, Beas river changed its course 250 years ago. Saraswati River of ancient past is supposed to have been captured by present day Yamuna River.
INTER-STATE WATER DISPUTES | Drainage System And Water
- After independence the demand for water had been increasing at an accelerated rate due to demand for agriculture, urbanization and industrialization, etc. But water is relatively a scarce resource in India due to monsoonal character of rainfall, fluctuating river regimes and frequent droughts. Almost all major rivers of India are inter-state rivers and there is tremendous competition among states to withdraw water from these rivers for their use.
- According to Indian Constitution, irrigation and water is a state subject. Therefore, State governments virtually exercise full control on planning, development, regulation, distribution and control of water flowing through their territory. Under Article 262 of the Constitution, the Parliament is empowered to provide for adjudication or control of water of any inter-state river. Under Water Disputes Act, 1956, a tribunal consisting of three sitting Judges of Supreme Court or High Court has to be constituted by the Central Government for the settlement of inter-state water dispute when a request is received from a state government. According to the Inter-State Water Disputes Act, 1968 the Central Government has also been given the responsibility of regulation and development of inter-state rivers and river valleys to the extent to which such regulation and development is required in public interest. The Parliament has also enacted the River Board Act 1956 which authorizes Central Government to constitute river boards in consultation with State Government for regulation and development of inter-state rivers. The draft National Water Policy, 2012 proposes a permanent Water Disputes Tribunal at the Centre.
SOME OF THE IMPORTANT INTER-STATE RIVER DISPUTES ARE AS UNDER:
- The Kaveri Water Dispute between Tamil Nadu, Karnataka and Kerala.
- The Krishna Water Dispute between Maharashtra, Karnataka, Andhra Pradesh.
- Tungabhadra Water Dispute between Andhra Pradesh and Karnataka.
- Godavari water dispute between Andhra Pradesh, Odisha, Chhattisgarh, Maharashtra and Madhya Pradesh.
- Narmada Water Dispute between Gujarat, Maharashtra, Madhya Pradesh and Rajasthan.
- Ravi and Beas Water Dispute between Punjab, Haryana, Himachal Pradesh, Rajasthan, Delhi, Jammu & Kashmir.
- Satluj – Yamuna link canal dispute between Punjab and Haryana and Rajasthan.
- Yamuna river water dispute between Delhi, Haryana, Uttar Pradesh, Rajasthan, Madhya Pradesh and Himachal Pradesh.
- Union Government makes many efforts to solve these disputes through negotiations and on the principle of ‘equitable sharing of water’. e. g. Pranahita river water dispute between Maharashtra, Chhattisgarh and Andhra Pradesh was settled through negotiations. On the other hand in many disputes a final solution acceptable to all parties has been difficult to work out due to economic, political and other reasons. The Kaveri Water dispute was resolved by Supreme Court in 2007, but the government and people of Karnataka were not satisfied with the judgement. Similarly sharing of Satluj and Yamuna waters has again become disputed after Punjab government terminated in water sharing agreement with neighbouring States of Haryana, HP, Jammu & Kashmir, Delhi and Rajasthan through a legislation in 2004. The matter is pending before Supreme Court.
- Such water disputes have hindered the development of total command area of inter-state rivers. Sometimes, there is demand for declaring rivers as national property. Inter-state water disputes are a big challenge for implementing river linking projects. These disputes should better be resolved through negotiations and mediations, so that universally accepted solution is derived.
INTER-LINKING OF RIVERS / NATIONAL WATER GRID
- Although India has vast water resources, these are not evenly distributed across time and space. Some rivers of India are perennial while other rivers go dry during summer season. Even during monsoon season floods and droughts are simultaneously seen in different parts of country. As a solution to this the inter-basin transfer of water or national river linking project has been frequently proposed even since British period (1839). Supreme Court of India too in the year 2002 and 2012 has suggested implementing river linking project. The project aims to connect major river basins through a network of canals, links, dams, etc. so as to transfer water from surplus to water deficit areas. The river linking project or the inter-basin transfer of water is designed to ease water shortages in western and southern India, while mitigating the impact of recurrent floods in the eastern parts of the Ganga basin.
- At its completion, the country will have 30 river links, 3,000 storage structures, a canal network stretching almost 15,000 km and can generate 34 GW of hydroelectric power, create some 87 million acres of irrigated land, and transfer 174 trillion litres of water a year. The initial cost of the project is estimated to be at Rs. 5.6 lakh crore, while around 580,000 people face the threat of displacement.
EARLIER EXAMPLES OF RIVER LINKING | Drainage System And Water
- There are already many small scale river linkages have already been implemented such as (1) Periyar diversion scheme (2) Kurnool-Cuddapah Canal (3) Parambikulam-Aliyar Project (4) Indira Gandhi Canal (5) Satluj-Beas link canal, etc. The National water grid is just an extension of the concept on a larger scale.
- THE PLAN
- Under the National Perspective Plan (NPP) prepared by the Ministry of Water Resources, the National Water Development Agency (NWDA) has identified 14 links under the Himalayan Component and 16 links under the Peninsular Rivers Component. According to the NPP, the Himalayan Rivers Development Project envisages construction of storage reservoirs on the main Ganga and the Brahmaputra and their principal tributaries in India and Nepal, along with an interlinking canal system to transfer surplus flow of the eastern tributaries of the Ganga to the West. It will also link the main Brahmaputra with the Ganga.
- The Peninsular Rivers Development Component is divided into four major parts:
- Interlinking of Mahanadi, Godavari, Krishna, Kaveri rivers and building storages at potential sites in these basins;
- Interlinking West flowing rivers north of Mumbai and south of the Tapi;
- Interlinking of Ken-Chambal; and
- Links between rivers of the Western Ghats to the East. The surplus water of west flowing rivers Western Ghat is frequently proposed to be diverted to its rainshadow areas through diversion canals. The Periyar Diversion Scheme is typical example of such model. The surplus water of Periyar river is collected in Mullaperiyar dam and then diverted via a tunnel across the Sahyadri to augment the small flow of Vaigai river, supplying water to Madurai region.
- The feasibility of National Water Grid has been studied by National Water Development Agency (NWDA), Central Water Commission, and Planning Commission etc.
PROPOSED BENEFITS | Drainage System And Water
- If completed, the project can yield following benefits:
- Water from surplus areas will be transferred to water deficit areas.
- Flood problem particularly in Bihar and Assam will be solved to great extent.
- Chronically drought affected areas will get sufficient water for irrigation, drinking and household and industrial uses.
- 34000 MW of hydroelectricity is estimated to be produced.
- It will create opportunities for inland water navigation.
- A minimum flow of water will be ensured in water deficit rivers.
- Water flowing wastefully into Bay and Bengal will be utilized.
CONCERNS | Drainage System And Water
- However, the project has been fraught with too many concerns, as following
- Environmentalists, hydrologists and economists around the world have expressed deep concerns at the irreversible damage that this sort of a mega project can do to the country’s environment including flora, fauna and biodiversity and our water resources. It will significantly disturb the ecosystem of all rivers, Central India as well as Sundarbans, mangroves and fisheries in West Bengal and Bangladesh delta.
- Hydrologists believe that there is hardly any surplus water in the country. There are serious ecological concerns. Big dams and canals will submerge forests, fertile soils and agricultural lands and disturb ecological balance.
- Massive civil works will be involved and vast sums of money will be required. It will involve huge cost of around Rs.5, 60,000 crore.
- Lakhs of people will be displaced. India’s record in rehabilitation and resettlement is very poor.
- It will be difficult to bring consensus among the states of India for transfer of water from their territory.
- International water sharing agreements with Bangladesh, Nepal, etc. will be difficult to come by.
Recently in 2012, the Union Government announced that considering human, ecological and economic costs of river linking project, it will not implement it. The government is now favouring alternative, cheaper and more sustainable solutions such as rain water harvesting ‘including recharging of ground water, linking of small and medium sized rivers and irrigation projects, etc. The new government in 2014 is again contemplating of implementing the project. Drainage System And Water