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

GNR 624 : Water Resources and River basin management Lesson 7 Water transfers in River basin Prof. R. Nagarajan, CSRE , IIT Bombay

GNR 624 : Water Resources and River basin management B arrage is a weir that has adjustable gates installed over top of it. The Farraka Barrage water level is adjusted by operating the adjustable gates. It is a type of 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. R eservoir 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 . 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. 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

GNR 624 : Water Resources and River basin management 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. 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. Prof. R. Nagarajan, CSRE , IIT Bombay

GNR 624 : Water Resources and River basin management 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. 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 a bout 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