Water transfers in River basin Prof. R. Nagarajan, CSRE , IIT Bombay - - PowerPoint PPT Presentation

Lesson 7

Water transfers in River basin

GNR 624 : Water Resources and River basin management

• Prof. R. Nagarajan, CSRE , IIT Bombay

Barrage is a weir that has adjustable gates installed over top of it. The water level is adjusted by operating the adjustable gates. It is a type

• f low-head, diversion dam, and thus regulate and stabilize river

water elevation upstream for use in irrigation and other systems Dam is a high impervious barrier constructed across a river valley to form a deep storage reservoir. Reservoir usually means an enlarged natural or artificial lake, storage pond or impoundment created using a dam or lock to store water. They can also be constructed in river valleys using a dam. Farraka Barrage Dam site Inter-basin transfer diversion, describe man-made conveyance schemes which move water from one river basin where it is available, to another basin where water is less available or could be utilized better for human development. Since conveyance of water between natural basins are described as both a subtraction at the source and as an addition at the destination, such projects may be controversial in some places and over time; they may also be seen as controversial due to their scale, costs and environmental or developmental impacts.

GNR 624 : Water Resources and River basin management

• Prof. R. Nagarajan, CSRE , IIT Bombay

Inter-basin Water Transfer Schemes Water transfers — massive engineering projects that divert water from rivers with perceived surpluses to those with shortages have been promoted as a solution but they aren’t always the answer Water transfer schemes attempt to make up for water shortages by constructing elaborate systems of canals, pipes, and dredging over long distances to convey water from one river basin (the donor basin) to another (the recipient basin). World’s rivers do not only get dammed, diverted and fragmented, parts of rivers get transferred to a different river basin altogether. Transfer projects typically involve in the construction of numerous dams and reservoirs, as well as tunnels and canals. Often, they involve excessive water withdrawals for agriculture. Two of the largest and most complicated water transfer projects are now set to go ahead in China and India. Spain was also planning a large-scale north-south transfer, but a recent change of government has put the plan under review

• Prof. R. Nagarajan, CSRE , IIT Bombay

• A. Demand Management
• 1. Reducing water demands;
• 2. Recycling waste water;
• 3. Assessing and promoting land use management or industrial development

alternatives.

• B. Supply Management
• 4. Trading in virtual water, and only then,
• 5. Supplementing water supplies locally, and only then,
• 6. Desalination in water-scarce coastal areas, and only then,
• 7. Considering an IBT, as a last option.

Inter-basin water transfers’ (IBTs) can potentially solve water supply issues in regions of water shortage. It comes with significant costs.

• Large scale IBT schemes are typically very high cost, and thus economically risky, and they usually also

come with significant social and environmental costs;

• usually for both the river basin providing and the river basin receiving the water.
• Climate-induced changes to hydrology now make these schemes more technically and economically risky.

GNR 624 : Water Resources and River basin management

• Prof. R. Nagarajan, CSRE , IIT Bombay

Impacts

• Water transfers seriously impact the environment of the donor basin. escalate threats to critically endangered

species, wetlands, and protected areas. Dams constructed on the river from which water is taken can devastate its ecology, disrupting environmental flows and blocking migrating fish. Economic and human costs

• Water transfer schemes compromise rivers’ ability to provide food and water. Even when "only" 10 to 15% of

water is taken from one basin, it can cause droughts in both basins in times of little rainfall.

• Projects have displaced entire communities who were not consulted on how they will be affected.
• Economic benefits generated in the recipient basin often come at the cost of those living in the donor basin.
• water transfer scheme is designed for the recipient’s benefit, but donor residents also face negative

consequences.

• water use in the donor basin is not evaluated prior to commitment to recipients as well the construction of a

water transfer project. This contributes to the continuation of unsustainable water use practices and,, increases the thirst for more water.

GNR 624 : Water Resources and River basin management

• Prof. R. Nagarajan, CSRE , IIT Bombay

Inter-basin water transfer (IBT) projects at a brisk pace during the past 50 years or so.

• China has steadfastly stayed course on its own scheme of transferring 48KM3 of water from Yangtze

to the Yellow to improve water availability in dry plains of North china.

• Elsewhere in the world many IBT projects have faced a variety of problems and produced some

unwanted side effects; however, in overall terms, most have tuned out to beneficial in balance.

• global environmental review of IBTs (Snaddon, Davis and Wishart 1999) advocates precautionary
• principle. concluded that: “In many parts of the world, water transfers have become the lifeblood of

developing and extant human settlements, for which no alternative is currently perceived to be available.” Colorado Big Thomson, USA diverts about 0.284km3/ annum of water from the upper reaches of the western flowing Colorado river and sends eastwards into the south Platte River Basin, which is a part of the Mississippi-Missouri basin. Completed in 1957. Lesotho Highlands Water Project, South Africa. Completed in 2004 diverts 750m3/ annum of water from Lesotho to South Africa.

• Prof. R. Nagarajan, CSRE , IIT Bombay

Existing transfers

Large inter-basin transfers are concentrated in Australia, Canada, China, India and the United States. National Water Carrier in Israel, transferring water from the Sea of Galilee (Jordan River Basin) to the Mediterranean coast lifting water over 372 meters. Its water is used both in agriculture and for municipal water supply. Mahaweli Ganga Project in Sri Lanka includes several inter basin transfers. Irtysh–Karaganda Canal in central Kazakhstan is about 450 km long with a maximum capacity of 75 cubic meters per second. It was built between 1962 and 1974 and involves a lift of 14 to 22 m. South–North Water Transfer Project in China, as well as other smaller-scale projects, such as the Irtysh– Karamay–Ürümqi Canal Africa From the Oum Er-Rbia River to supply Casablanca in Morocco with drinking water From the tributaries of Ichkeul Lake in Tunisia to supply Tunis with drinking water From Lake Nasser on the Nile to the New Valley Project in the Western Desert of Egypt The Lesotho Highlands Water Project to supply water to Gauteng in South Africa

• Prof. R. Nagarajan, CSRE , IIT Bombay

America

• Los Angeles Aqueduct completed in 1913 transferring water from the Owens Valley to Los Angeles
• Colorado River Aqueduct built in 1933-1941 to supply Southern California with water
• California State Water Project built in stages in the 1960s and 1970s to transfer water from Northern to

Southern California. It includes the California Aqueduct and the Edmonston Pumping Plant, which lifts water nearly 600 meters up and over the Tehachapi Mountains through 10 miles of tunnels for municipal water supply in the Los Angeles Metropolitan area.

• Cutzamala System built in stages from the late 1970s to the late 1990s to transfer water from the Cutzamala

River to Mexico City for use as drinking water, lifting it over more than 1000 meters. It utilizes 7 reservoirs, a 127 km long aqueduct with 21 km of tunnels, 7.5 km open canal, and a water treatment plant.

• Central Utah Project to supply the Wasatch Front with urban water and for irrigation
• San Juan-Chama Project to bring water from the Colorado River basin into the Rio Grande basin for urban and

agricultural purposes

• Prof. R. Nagarajan, CSRE , IIT Bombay

Asia - India Periyar Project in Southern India from the Periyar River in Kerala to the Vaigai basin in Tamil Nadu. It consists of a dam and a tunnel with a discharging capacity of 40.75 cubic meters per second. The project was commissioned in 1895 and provides irrigation to 81,000 hectares, in addition to providing power through a plant with a capacity of 140 MW. Parambikulam Aliyar project, in Southern India, consists of seven streams, five flowing towards the west and two towards the east, which have been dammed and interlinked by tunnels. The project transfers water from the Chalakudy River basin to the Bharatapuzha and Cauvery basins for irrigation in Coimbatore district of Tamil Nadu and the Chittur area of Kerala states. It also serves for power generation with a capacity of 185 MW. Kurnool Cudappah Canal in Southern India is a scheme started by a private company in 1863, transferring water from the Krishna River basin to the Pennar basin. It includes a 304 km long canal with a capacity of 84.9 cubic meters per second for irrigation. Telugu Ganga project in Southern India. This project primarily meets the water supply needs of Chennai metropolitan area, but is also used for irrigation. It brings Krishna River water through 406 km of canals. The cooperation of four Indian States: Maharashtra, Karnataka, Andhra Pradesh and Tamil Nadu. Indira Gandhi Canal (Rajasthan Canal) linking the Ravi River, the Beas River and the Sutlej River through a system of dams, hydropower plants, tunnels, canals and irrigation systems in Northern India built in the 1960s to irrigate the Thar Desert.

• Prof. R. Nagarajan, CSRE , IIT Bombay

IBT’s negative attributes:

• Demand management in the recipient basin was not a serious part of pre-planning for IBT, leading to on-going

water wastage

• Became a driver for unsustainable irrigation or urban water use in the recipient basin
• IBT scheme created strong dependence in the recipient community. Promoted unsustainable activities, not

improved water use efficiencies or find alternative water sources/supplies

• water supplementation methods such groundwater extraction, desalinisation, recycling etc
• The donor basin experiences serious environmental impacts through reduced flows especially
• Escalated threats to critically endangered, threatened species, Ramsar listed wetlands, protected areas sites etc
• The transfer scheme saw economic benefits in recipient basin at the cost of communities in the donor basin
• Served as a catalyst for social conflict between the donor and recipient basins or with government
• Not helped the situation of the poor affected or displaced by it
• Mitigation costs have proven very high, either environmentally or socially
• Governance arrangements are weak, resulting in budget blow-outs or corruption (in some cases)
• Climate change impacts have generally not been considered in planning these IBTs increasing the risk that these

large, inflexible investments may become largely redundant.

• Prof. R. Nagarajan, CSRE , IIT Bombay

• 1. Before progressing to commission an IBT, there should be a comprehensive assessment of the alternatives

available for providing the water needed in the proposed recipient basin. Can this water be provided through demand management, water recycling, water harvesting, virtual water trades etc, before considering a major infrastructure investment with its possible environmental and social impacts? Or is there an alternative to meet this demand by importing water intensive products from water rich regions, thus promoting virtual water transfer rather than to rely on real water transfers?

• 2. Undertake a cost-benefit analysis of the likely impacts of the IBT on both the donor and recipient basins,

considering the full range of environmental, social and economic implications.

• 3. Ensure risks associated with the proposed IBT; environmental (including climatic), social and economic are

clearly understood, and if the project proceeds, governance arrangements are adequate to manage and minimise these risks.

• 4. Undertake consultations with the likely directly and indirectly affected people, before a decision is taken

regarding the possible IBT (and certainly before it becomes fait accompli) ensuring they understand and have the

• pportunity to voice views on likely cost, benefits and risks
• Prof. R. Nagarajan, CSRE , IIT Bombay

Weaknesses in IBT planning:

• 1. Apart from hydropower generation, a common driver of IBTs is a desire to promote agricultural

production in water poor areas, and, in particular irrigated agriculture. unsustainable cropping practices are promoted

• 2. There is typically a failure to examine alternatives to the IBT that may mean delaying, deferring
• r avoiding the costs
• 3. Range of governance failures ranging from poor to non-existent consultation with affected

people, to failing to give sufficient consideration or weight to the environmental, social and cultural impacts in both the donor and recipient basins.

• 4. IBTs promoting agricultural production in water poor areas
• 5. IBTs that fail to examine alternatives
• Prof. R. Nagarajan, CSRE , IIT Bombay

1) Eliminating losses in their current water supply network 2) Increase water use efficiencies 3) Conjunctive use of water and ground water resources 4) Increasing water prices to promote water use efficiency and shift water use from low value to higher value production systems; 5) Reclamation of wastewater in municipal areas; reviewing policy and regulations; and improving monitoring.’ Water conservation measures that can be used as a substitute for inter-basin water transfer projects and new sources of water supply include the following” and go onto detail:

• Increasing water use efficiency;
• Water trading;
• Wastewater reclamation;
• Conjunctive use of surface and groundwater;
• Water metering and pricing;
• Cloud seeding;
• Water desalination; and
• Building new dams.
• Prof. R. Nagarajan, CSRE , IIT Bombay

Assessment of inter-basin water transfers a) Economic productivity impacts 1: The area of delivery must face a substantial deficit in meeting present or projected future water demands after consideration is given to alternative water supply sources and all reasonable measures for reducing water demand. 2: The future development of the area of origin must not be substantially constrained by water scarcity; however, consideration to transfer that constrains future development of an area of origin may be appropriate if the area of delivery compensates the area of origin for productivity losses. b) Environmental quality impacts 3: A comprehensive environmental impact assessment must indicate a reasonable degree of certainty that it will not substantially degrade environmental quality within the area of origin or area of delivery; however, transfer may be justified where compensation to offset environmental injury is provided. c) Socio-cultural impacts 4: A comprehensive assessment of sociocultural impacts must indicate a reasonable degree of certainty that it will not cause substantial sociocultural disruption in the area of origin or area of water delivery: however, transfer may be justified where compensation to offset potential socio-cultural losses is provided. d) Benefit distribution considerations 5: The net benefits from transfer must be shared equitably between the area of transfer origin and the area of water delivery.

• Prof. R. Nagarajan, CSRE , IIT Bombay

Linking of rivers

• means diverting water from the Potentially Utilizable Water Resources (PUWR)
• basins have excess PUWR for transfer to other basins, after meeting the additional future

demand of all other sectors in the basin? Which

• basins can divert un-utilizable renewable water resources to water-scarce regions?
• research to understand the benefits and costs of a water transfer program.

Analyses of water supply and demand across river basins indicate

• some basins are physically water-scarce due to inadequate availability of water in the basin,
• thers are physically water-scarce due to excessive development in the basin.
• Water scarcity in some basins is exacerbated by unsustainable groundwater use and these basins

are characterized by high dependency on other basins for food

• Prof. R. Nagarajan, CSRE , IIT Bombay

India’s future water is based on supply and demand.

• Spatial variation and future growth of the population,
• urbanization and income, and associated changes in dietary preferences, on the crop-

consumption side;

• growth in crop yield, cropping intensity and groundwater use,
• contribution to production from rain-fed agriculture, on the crop-production side
• future growth in other factors such as domestic, industrial and environmental water demand,
• internal and international trade.

GNR 624 : Water Resources and River basin management

• Prof. R. Nagarajan, CSRE , IIT Bombay

GNR 624 : Water Resources and River basin management

• Prof. R. Nagarajan, CSRE , IIT Bombay

Other aspects of the project that are

• International implications: The Ganga crosses international boundaries, and any development or

diversions within an international watershed has implications

• Analysis specific to agriculture: potential health and environmental effects of new irrigation projects, we do

not attempt to provide analysis of the potential economic and social benefits increased agricultural productivity would bring.

• Project costs: specifics of the project remain unclear at this point
• Engineering design: actual engineering design of the project will be, so we are unable to make true

projections about how many people will be displaced and what the future externalities might be to populations living close to reservoirs and irrigation canals. height of the proposed dams, and have relied on speculation and estimates in our discussion of hydropower and the ILR.

• The Ganga-Brahmaputra-Megna basin begins in the Himalayas and flows through northern India

through Bangladesh to the Bay of Bengal. The Ganga is said to provide water to 37 percent of the geographical area of Bangladesh, over which one third of the population depends.

• Prof. R. Nagarajan, CSRE , IIT Bombay

Merits

• Alleviating droughts and flood control.
• Cheap water for irrigation.
• Availability of drinking water.
• Generation of hydroelectric power.
• Allowing more inland navigation.
• Employment generation.
• Fostering a spirit of national integration.

Issues

Riparian rights: conflict between states (as- kauveri and Mahanadi issue) have to be resolved. In addition worry of Bangladesh and Nepal have to be taken into account. Financing: Raising 5.6 lakh crores of rupees is a tough task and if created maintenance of huge asset is a problem. Fear of privatization of water resources. Flood period: Idea of networking flood water to the deficient basin does not consider the surplus period of donor area and deficient period of recipient area.

• Prof. R. Nagarajan, CSRE , IIT Bombay

Desertification: Prevention of natural flooding may led to desertification as there will be loss of fertile soil. River pollution: Reducing the flow of river by diversion will increase the concentration of pollutants in the river. Security: Security of network will be an enormous load on security forces of central and state

• governments. As canal can be easily breached by manual or natural activities.

Land acquisition and displacement: Misery and injustice to the displaced people in obtaining compensation due to systemic corruption. Technical feasibility: The slope, altitude and other topographical aspects have to be considered. (e.g. for Ganga, Patna is diversible surplus but for raising water to Vindhya chain i.e. 2860 ft. high enormous amount of power is required).

• Prof. R. Nagarajan, CSRE , IIT Bombay

• Prof. R. Nagarajan, CSRE , IIT Bombay

• Prof. R. Nagarajan, CSRE , IIT Bombay

• Prof. R. Nagarajan, CSRE , IIT Bombay

GNR 624 : Water Resources and River basin management

• Prof. R. Nagarajan, CSRE , IIT Bombay

• Prof. R. Nagarajan, CSRE , IIT Bombay

GNR 624 : Water Resources and River basin management

• Prof. R. Nagarajan, CSRE , IIT Bombay

GNR 624 : Water Resources and River basin management

• Prof. R. Nagarajan, CSRE , IIT Bombay

Thank you