Seminar Report On
“SEDIMENT CONTROL MEASURE IN RESERVOIR”
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Seminar Report On
“SEDIMENT CONTROL MEASURE IN RESERVOIR”
To Download Click Here:
Climate change is a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. It may be a change in average weather conditions, or in the distribution of weather around the average conditions (i.e., more or fewer extreme weather events). Climate change is caused by factors that include oceanic processes (such as oceanic circulation), biotic processes, variations insolar radiation received by Earth, plate tectonics and volcanic eruptions, and human-induced alterations of the natural world; these human-induced effects are currently causing global warming, and “climate change” is often used to describe human-specific impacts.
The decline in Arctic sea ice, both in extent and thickness, over the last several decades is further evidence for rapid climate change. Sea ice is frozen seawater that floats on the ocean surface. It covers millions of square miles in the polar regions, varying with the seasons. In the Arctic, some sea ice remains year after year, whereas almost all Southern Ocean or Antarctic sea ice melts away and reforms annually. Satellite observations show that Arctic sea ice is now declining at a rate of 11.5 percent per decade, relative to the 1979 to 2000 average.
Fusegates are an innovative spillway control technology, which consists of free standing blocks (the Fusegates) set side by side on a flattened spillway sill. The Fusegate blocks act as a fixed weir most of the time and operate independently without any remote control or energy source only in case of excessive flood conditions.
The System is developed and patented by Hydroplus from Paris, France. It has been installed on more than 50 dams around the world with sizes ranging from 1m to more than 9m in height. Fusegate are typically used to increase the storage capacity of existing dams or to maximize the discharge potential of undersized spillways.
Throughout history man has been building dams for various reasons, whether it was to prevent floods, generate electricity, or create a water supply. Starting thousands of years ago in the middle east as small walls, today dams are immensely huge power generation facilities that fulfill a number of tasks and take years to build. So, whether you recognize the impact these architectural wonders have had on your life or not, these are the 25 tallest dams in the world. (courtesy: http://list25.com)
A hydroelectric and irrigation dam on the Naryn River in the Jalal-Abad Province of Kyrgyzstan, this dam is the shortest on our list at 215 meters high.
Longtan Dam is a large roller-compacted concrete gravity dam on the Hongshui River in China. It stands at 216.5 meters.
Named for Glen Canyon, a colorful series of gorges most of which now lies under the reservoir, the dam created the second largest artificial lake in the United States.
At 219 meters, Dworshak is the third tallest dam in the United States and the tallest straight-axis concrete dam in the Western Hemisphere.
Commonly known as the Verzasca Dam and the Locarno Dam, the Contra is an arch dam on the Verzasca River in Switzerland.
Once known as Boulder Dam, the Hoover Dam is a concrete arch-gravity dam in the Black Canyon of the Colorado River, on the border between the US states of Arizona and Nevada.
Featuring the world’s highest artificial climbing wall on one of its sides, this dam stands at 225 meters.
This is a concrete gravity dam across the Sutlej River near the border between Punjab and Himachal Pradesh in northern India.
An arch dam on the Karun River in Iran its primary objectives are electric power supply and flood control.
Built not just for power but also to promote flood control, navigation, tourism and fishery, the Shuibuya Dam is 233 meters tall.
This arch dam on the Sulak River is the tallest arch dam in Russia at 232.5 meters.
Officially known as Central Hidroeléctrica Francisco Morazán, this dam is a hydroelectric power plant located in Western Honduras.
At 230 meters high this earthfill embankment dam on the Feather River in California is the tallest in the United States.
This 240 meter high arch dam can be found on the Yalong River, a tributary of the Yangtze River in Sichuan Province, southwest China
Located on the Yenisei River, near Sayanogorsk in Russia, this dam is the largest power plant in the country and the sixth-largest hydroelectric plant in the world.
This 243 meter high dam spans the Colombia River 135 kilometres north of Revelstoke, Canada.
Named after İbrahim Deriner, who died while serving as the Chief Engineer of its research team, the dam is located on the Çoruh River 3 miles east of Artvin, Turkey.
The Laxiwa Dam is a 250 meter high arch dam on the Yellow River in Qinghai Province, northwest China.
With Mont Blanc de Cheilon in the background the Mauvoisin Dam creates the Lac de Mauvoisin in the Swiss alps.
This multi-purpose rock and earth-fill embankment dam on the Bhagirathi River near Tehri in Uttarakhand, India is 261 meters high.
A disused dam north of Venice, Italy, in 1963 a landslide caused the overtopping of the dam and around 2,000 deaths.
This hydroelectric dam on the Inguri River in Georgia is the second highest concrete arch dam in the world.
A concrete gravity dam on the Dixence River in Switzerland, at 285 meters it is the tallest of its kind in the world.
An arch dam on the Lancang (Mekong) River in China, its primary purpose is to provide hydroelectric power.
This earth fill embankment dam on the Vakhsh River in Tajikistan is currently the tallest dam in the world at 300 meters.
Sardar Sarovar Dam (SSD), on the Indian Narmada river, is located in the village of Kevadia in the state of Gujarat. It is one of the largest and most controversial interstate, multipurpose river valley infrastructure development projects in the country. The Sardar Sarovar Project (SSP) also consists of auxiliary works and a 1,450MW power complex.
SSP was estimated to have cost INR400bn ($8bn) in 2010-2011, revised from the initial estimate of INR64bn ($1.25bn) in 1988. It is part of the Narmada Valley Development Project, a major plan to generate power and supply water for drinking and irrigation to states of Gujarat, Madhya Pradesh and Maharashtra.
The scheme was conceived by the late Sardar Vallabhbhai Patel in 1946-1947. It envisages the construction of 30 major dams, 135 medium and 3,000 smaller dams along the river, with SSD being the largest of them all. They are expected to generate about 4,000MW of power in total.
Height of the Sardar Sarovar Dam in Gujarat was increased to 121.9m in 2006.
The SSD is a 1,210m long concrete gravity dam with a proposed final height of 163m above the deep foundation. Its present height is 121.9m. Its construction required pouring of about seven million cubic metres of chilled concrete. The Sardar Sarovar reservoir, built for the main dam, has 0.95 million hectare metre (M.Ha.m) of gross storage capacity and 0.586M.Ha.m of live storage capacity.
It occupies an area of 37,000ha with an average length of 214km and width of 1.7km. The river catchment area above the dam site is 88,000 square kilometres. It has a spillway discharging capacity of 87,000 cubic metres a second.
The dam and the reservoir periphery have been installed with advanced seismological instruments for calculating the stresses. Seven chute spillway radial gates and 23 service spillway gates are installed for flood control. The full reservoir level of the SSD is 138.6m, the maximum water level is 140.2m and minimum draw down level is 110.6m. The tail water level is about 25.9m.
The Narmada Main Canal is the largest irrigation lined canal in the world, supplying water at a capacity of 1,133 cubic metres a second. Image courtesy of Nvvchar.
The Sardar Sarovar Dam and associated water infrastructure is expected to supply water for irrigation of 1.84 million hectares in Gujarat. Image courtesy of Nvvchar.
Narmada is the fifth largest river in India, traversing 1,312km from the Amarkantak range in Madhya Pradesh to drain into the Arabian Sea at the Gulf of Cambay. The river has a basin area of 97,410 square kilometres.
The SSP is expected to supply water for irrigation of 1.84 million ha of land across 15 districts and 73 suburbs including drought prone regions in Gujarat, as well as two districts of Rajasthan. It is also expected to supply drinking water to 29 million inhabitants across 131 towns and 9,633 villages in the state.
It will supply water to wildlife sanctuaries and industries, as well as secure the needs of Gujarat’s expected population of 40 million, projected by 2021.
A state-wide drinking water grid is expected to supply for about 75% of the Gujarat population. Gujarat Water Infrastructure and the Gujarat Water Supply and Sewage Board (GWSSB) are executing this Narmada Master Plan.
The 66,000km network of conveyance and distribution system includes the Narmada Main Canal (NMC), about 2,500km of branch canals, 5,500km of distributaries and other associated channels. The 458.3km long, 1,133 cubic metres a second capacity NMC in Gujarat is the largest irrigation lined canal in the world. It further extends by 74km in Rajasthan. It also has 38 off-taking branch canals being built in phases and is scheduled for completion by 2025.
Plans for the dam projects in the Narmada basin were initiated in 1946. The SSP project has been under constant criticism since its early stages. Its construction was halted several times due to court stay orders and oppositions.
Works could not start due to water sharing disputes among the concerned Maharashtra, Rajasthan, Gujarat and Madhya Pradesh states. The Narmada Water Dispute Tribunal (NWDT) was formed in October 1969 to resolve the issues and allocate the water shares. NWDT reached an agreement in 1979 and construction of the dam was started in April 1987. The construction was backed by funds from the World Bank.
A group of local people opposed the project in 1989 under the Narmada Bachao Andolan (NBA, or Save the Narmada Movement). The World Bank withdrew the funding in 1993 following immense protests, resulting in delays to the project.
Construction was halted as per the Supreme Court’s stay in May 1995. It resumed in February 1999 and the dam’s height was increased from the planned 80m to 88m. The Court allowed the increase of the dam’s height to 90m in October 2000, but ordered adherence to the rehabilitation and resettlement issues. The dam’s height was increased to 110.6m with the approval from Narmada Control Authority, in June 2004. It was further raised to its current 121.9m height in December 2006.
NBA claims the government has overlooked the environmental impact, resettlement of 320,000 people and exaggerated project benefits. About one million people are estimated to be affected by the river canal and associated works. Several other local groups across the states concerned also opposed the SSP.
The SSP has two hydropower generating units. The 1,200MW underground river bed power house (RBPH) station has six, 200MW units of reversible Francis type turbines, supplied by Sumitomo and BHEL.
The 250MW surface canal head power house (CHPH) consists of five, 50MW Kaplan turbines. The CHPH power units were commissioned by December 2004 and RBPH by November 2006. The power stations are connected to a Gas Insulated Switch Gear and bus bars switchyard complex in RBPH. Electricity is distributed to Gujarat (16%), Madhya Pradesh (57%) and Maharashtra (27%) through a 400kV power transmission line.
Sardar Sarovar Narmada Nigam (SSNL), a state-owned company, is responsible for implementing and managing the SSP. Jaiprakash Associates was the engineering, procurement and construction contractor for the dam and power house. Gujarat State Electricity Company operates and maintains the power complex.
Structure at the head of canal taking off from a reservoir may consist of nu ber of spans separated by piers and operated by gates.
Regulators are normally aligned at 90° to the weir. upto 10″ are considered preferable for smooth entry into canal. These are used for diversion of flow. Silt reduces carriage capacity of flow.
Still pond regulation:
Open flow regulation:
Silt control devices: