Dam it Multi purpose river projects and

Dam – it! Multi purpose river projects and Integrated water resources Management Std X CBSE As per NCERT geography textbook Contemporary India II

October 1963 Dakotas of the Indian Air Force dipped their wings overhead. Pundit Nehru flicked on the switch of the powerhouse and opened the sluice gates of the dam. Villagers downstream celebrated and set off fireworks In his speech dedicating the dam to the nation, he called dams as the ‘Temple of modern India’

Which project are we talking abo Bhakra Dam

The Grand Anicut was built during the Chola Was this water regulating water It is the oldest the firstlong as 3 structure and Dynasty regulating fields Made of stone, it is as football structure to is A. D in India? be built in the 1 st / 2 nd century still. to harness the waters of the very much in use. river Cauvery. Photo by Claire Arni and Oriole Henri

A dam is a barrier across flowing water It obstructs, directs, or retards the flow of water. It usually creates a reservoir Surplus water flows out over spillways Sluice Reservoir / Radial Gates control the flow of water downstream (most gates today are radial gates) Spillways Power House River Long Distance Power Lines Gate Generator Intake Turbin e River

Classification of Dams Based on size – Large dams (>15 meters) Major dams (over 150 meters in height) Sometimes also classified as low, medium and high. Based on structure and material used – Timber dams, Arch gravity dams, Embankment dams or Masonry dams, with several sub types. Based on purpose - Saddle dam, Dry dam, Diversion dam Why do you think dams are broader at the bottom than at the top?

Earlier water regulating structures impounded water for irrigation Today, as the name suggests – they are Multi-purpose river projects

Power 270 million gallons of drinking water per day 10 the industrialized areas of to million acres in Punjab, 1204 MW Pradesh, Delhi, Himachal Delhi, Uttar Pradesh and Uttarakhand Haryana and Rajasthan Tehri Irrigation Domestic Kutch , Saurashtra Water Supply 1920 MW 1181 MW controls flooding of the lower delta region by the Mahanadi river 815. 6 MW Flood Control

Inland Navigation water-skiing, sailing, kayaking, speed boating and water scooter racing Tehri fifty one species and sub species of fish. Also a water fowl refuge Recreation Fish Breeding diverts water from the Ganga into the Hoogly during the dry season to flush out accumulated silt and allow navigation through the Hoogly into the port of Kolkata

Temples of modern India industries water supply livelihood + fishing hydropower for electricity irrigation Inland Navigation Flood Control

Temples of modern India? Loss of natural biodiversity Evaporation, Green House Gas emission Displacement of local trib Destruction of historical and archaeological sites Loss of Livelihood

Temples of modern India? Fragmentation of river ecosystems and Impacts biodiversity • Barrier for movement of migratory fish like the salmon, thereby affecting its population • Reduction in natural biodiversity along riverbanks due to reduced natural flooding • Alters water temperature downstream, affecting plant and animal life in the reservoir and the river

Reservoir Sedimentation Sediments that naturally flow in a river are blocked Reservoir storage capacity reduces Power generation and water availability reduces Downstream erosion Lesser sediments reach downstream Water flow eats into riverbed and shore (erosion) affects biodiversity in and along the river and increases coastal erosion

Temples of modern India? Other social and ecological impacts: Cropping patterns changed to more water intensive crops – affects soil quality Water disputes • Inter-state water disputes Maharastra vs. Karnataka and AP Karnataka vs. TN • Between farmers and urban areas are water disputes caused by a But Sabarmati basin mismatch in demand supply? Do Cauvery basin dams actually ease disputes by providing water during lean periods? Debate this in class.

the disputes. Let’s play a gam

Hangman • Divide the class into 5 teams • Draw as many dashes as in the name of a dam / reservoir / barrage. ____ • Team A starts. They guess a letter. The teacher puts in the letter at the correct place, if it is there in the name of the dam. Else, the letter is written down on one side. • A maximum of 10 wrong guesses are allowed. • The team gets as many points as letters on the side (maximum of 10). • The team with the lowest number of points wins

Point the correct position of the dam/ reservoir / barrage on the map and get 2 points reduced from your points tally Source: Maps of India

Activity 1 sign the following roles to students Role play • A bench of 5 Supreme Court Judges • A person who will lose his home and lands by construction of a dam • A passionate environmentalist • A farmer downstream, plagued by seasonal floods and drought • An industrialist • A politician from a nearby urban constituency

Activity 1 Role Play • Select a river in your state • Let each party put forward their views on the construction of a multi-purpose river project that will directly affect them • Let each party also put forth solutions for opposing factions • The judges can take a decision on the project depending on the case put forth

Activity 2 sion scus i D • Divide the class into 2 teams • Discuss the pros and cons of the dam built at Tehri or Koyna (let the students research the facts before the classroom discussion)