A water turbine is a rotary machine that converts kinetic energy and potential energy of water into mechanical work. Water turbines were developed in the 19th century and were used for industrial power prior to electrical grids. Now they are used for electric power generation. Water turbines are found in dams to generate electric power from water kinetic energy. Water wheels have been used for hundreds of years for industrial power, their main shortcoming is size, which limits the flow head that can be harnessed. The migration from water wheels to modern turbines took about one hundred years. Development occurred during the Industrial revolution, using scientific methods, they made extensive use of new materials and manufacturing methods developed at the time. The word turbine was introduced by the French engineer Claude Burdin in the early 19th century and is derived from the Greek word "τύρβη" for "whirling" or a "vortex"; the main difference between early water turbines and water wheels is a swirl component of the water which passes energy to a spinning rotor.
This additional component of motion allowed the turbine to be smaller than a water wheel of the same power. They could harness much greater heads; the earliest known water turbines date to the Roman Empire. Two helix-turbine mill sites of identical design were found at Chemtou and Testour, modern-day Tunisia, dating to the late 3rd or early 4th century AD; the horizontal water wheel with angled blades was installed at the bottom of a water-filled, circular shaft. The water from the mill-race entered the pit tangentially, creating a swirling water column which made the submerged wheel act like a true turbine. Fausto Veranzio in his book Machinae Novae described a vertical axis mill with a rotor similar to that of a Francis turbine. Johann Segner developed a reactive water turbine in the mid-18th century in Kingdom of Hungary, it was a precursor to modern water turbines. It is a simple machine, still produced today for use in small hydro sites. Segner worked with Euler on some of the early mathematical theories of turbine design.
In the 18th century, a Dr. Robert Barker invented a similar reaction hydraulic turbine that became popular as a lecture-hall demonstration; the only known surviving example of this type of engine used in power production, dating from 1851, is found at Hacienda Buena Vista in Ponce, Puerto Rico. In 1820, Jean-Victor Poncelet developed an inward-flow turbine. In 1826, Benoît Fourneyron developed an outward-flow turbine; this was an efficient machine. The stationary outlet had curved guides. In 1844, Uriah A. Boyden developed an outward flow turbine that improved on the performance of the Fourneyron turbine, its runner shape was similar to that of a Francis turbine. In 1849, James B. Francis improved the inward flow reaction turbine to over 90% efficiency, he conducted sophisticated tests and developed engineering methods for water turbine design. The Francis turbine, named for him, is the first modern water turbine, it is still the most used water turbine in the world today. The Francis turbine is called a radial flow turbine, since water flows from the outer circumference towards the centre of runner.
Inward flow water turbines have a better mechanical arrangement and all modern reaction water turbines are of this design. As the water swirls inward, it accelerates, transfers energy to the runner. Water pressure decreases to atmospheric, or in some cases subatmospheric, as the water passes through the turbine blades and loses energy. Around 1890, the modern fluid bearing was invented, now universally used to support heavy water turbine spindles; as of 2002, fluid bearings appear to have a mean time between failures of more than 1300 years. Around 1913, Viktor Kaplan created a propeller-type machine, it was an evolution of the Francis turbine but revolutionized the ability to develop low-head hydro sites. All common water machines until the late 19th century were reaction machines. A reaction turbine needs to contain the water during energy transfer. In 1866, California millwright Samuel Knight invented a machine that took the impulse system to a new level. Inspired by the high pressure jet systems used in hydraulic mining in the gold fields, Knight developed a bucketed wheel which captured the energy of a free jet, which had converted a high head of water to kinetic energy.
This is called tangential turbine. The water's velocity twice the velocity of the bucket periphery, does a U-turn in the bucket and drops out of the runner at low velocity. In 1879, Lester Pelton, experimenting with a Knight Wheel, developed a Pelton wheel, which exhausted the water to the side, eliminating some energy loss of the Knight wheel which exhausted some water back against the center of the wheel. In about 1895, William Doble improved on Pelton's half-cylindrical bucket form with an elliptical bucket that included a cut in it to allow the jet a cleaner bucket entry; this is the modern form of the Pelton turbine. Pelton had been quite an effective promoter of his design and although Doble took over the Pelton company he did not change the name to Doble because it had brand name recognition. Turgo and cross-flow turbines were impulse designs. Flowing water is directed on to the blades of a turbine runner, creating a force on the
Flood control methods are used to reduce or prevent the detrimental effects of flood waters. Flood relief methods are used to reduce the effects of high water levels. Floods are caused by many factors or a combination of any of these prolonged heavy rainfall accelerated snowmelt, severe winds over water, unusual high tides, tsunamis, or failure of dams, retention ponds, or other structures that retained the water. Flooding can be exacerbated by increased amounts of impervious surface or by other natural hazards such as wildfires, which reduce the supply of vegetation that can absorb rainfall. Periodic floods occur on many rivers. During times of rain, some of the water is retained in ponds or soil, some is absorbed by grass and vegetation, some evaporates, the rest travels over the land as surface runoff. Floods occur when ponds, riverbeds and vegetation cannot absorb all the water. Water runs off the land in quantities that cannot be carried within stream channels or retained in natural ponds and man-made reservoirs.
About 30 percent of all precipitation becomes runoff and that amount might be increased by water from melting snow. River flooding is caused by heavy rain, sometimes increased by melting snow. A flood that rises with little or no warning, is called a flash flood. Flash floods result from intense rainfall over a small area, or if the area was saturated from previous precipitation; when rainfall is light, the shorelines of lakes and bays can be flooded by severe winds—such as during hurricanes—that blow water into the shore areas. Coastal areas are sometimes flooded by unusually high tides, such as spring tides when compounded by high winds and storm surges. Flooding has many impacts, it endangers the lives of humans and other species. Rapid water runoff causes soil erosion and concomitant sediment deposition elsewhere; the spawning grounds for fish and other wildlife habitats can become polluted or destroyed. Some prolonged high floods can delay traffic in areas. Floods can interfere with drainage and economical use such as interfering with farming.
Structural damage can occur in bridge abutments, bank lines, sewer lines, other structures within floodways. Waterway navigation and hydroelectric power are impaired. Financial losses due to floods are millions of dollars each year, with the worst floods in recent U. S. history having cost billions of dollars. There are many disruptive effects of flooding on economic activities. However, flooding can bring benefits, such as making soil more fertile and providing nutrients in which it is deficient. Periodic flooding was essential to the well-being of ancient communities along the Tigris-Euphrates Rivers, the Nile River, the Indus River, the Ganges and the Yellow River, among others; the viability for hydrologically based renewable sources of energy is higher in flood-prone regions. This is the method used for remote sensing the disasters. Detection of disasters such as floods and explosions are quite complex in previous days and range of detection is inappropriate. But, it came to possibilities by using Multi temporal visualization of Synthetic Aperture Radar images.
But to obtain the good SAR images perfect spatial registration and precise calibration are necessary to specify changes that have occurred. Calibration of SAR is complex and a sensitive problem. Errors may occur after calibration that involves data fusion and visualization process. Traditional image pre-processing cannot be used here due to the on-Gaussian of radar back scattering, but a processing method called "cross calibration/normalization" is used to solve this problem; the application generates a single disaster image called "fast-ready disaster map" from multitemporal SAR images. These maps are generated without user interaction and helps in providing immediate first aid to the people; this process provides image enhancement and comparison between numerous images using data fusion and visualization process. This proposed processing includes histogram truncation and equalization steps; the process helps in identifying the permanent waters and other classes by combined composition of pre-disaster and post-disaster images into a color image for better identity.
Some methods of flood control have been practiced since ancient times. These methods include planting vegetation to retain extra water, terracing hillsides to slow flow downhill, the construction of floodways. Other techniques include the construction of levees, dams, retention ponds to hold extra water during times of flooding. Many dams and their associated reservoirs are designed or to aid in flood protection and control. Many large dams have flood-control reservations in which the level of a reservoir must be kept below a certain elevation before the onset of the rainy/summer melt season to allow a certain amount of space in which floodwaters can fill. Other beneficial uses of dam created reservoirs include hydroelectric power generation, water conservation, recreation. Reservoir and dam construction and design is based upon standards set out by the government. In the United States and reservoir design is regulated by the US Army Corps of Engineers. Design of a dam and reservoir follows guidelines set by the USACE and covers topics such as design flow rates in consideration to meteorological, topographic and soi
South Carolina is a state in the Southeastern United States and the easternmost of the Deep South. It is bordered to the north by North Carolina, to the southeast by the Atlantic Ocean, to the southwest by Georgia across the Savannah River. South Carolina became the eighth state to ratify the U. S. Constitution on May 23, 1788. South Carolina became the first state to vote in favor of secession from the Union on December 20, 1860. After the American Civil War, it was readmitted into the United States on June 25, 1868. South Carolina is the 40th most extensive and 23rd most populous U. S. state. Its GDP as of 2013 was $183.6 billion, with an annual growth rate of 3.13%. South Carolina is composed of 46 counties; the capital is Columbia with a 2017 population of 133,114. The Greenville-Anderson-Mauldin metropolitan area is the largest in the state, with a 2017 population estimate of 895,923. South Carolina is named in honor of King Charles I of England, who first formed the English colony, with Carolus being Latin for "Charles".
South Carolina is known for its 187 miles of coastline, beautiful lush gardens, historic sites and Southern plantations, colonial and European cultures, its growing economic development. The state can be divided into three geographic areas. From east to west: the Atlantic coastal plain, the Piedmont, the Blue Ridge Mountains. Locally, the coastal plain is referred to the other two regions as Upstate; the Atlantic Coastal Plain makes up two-thirds of the state. Its eastern border is a chain of tidal and barrier islands; the border between the low country and the up country is defined by the Atlantic Seaboard fall line, which marks the limit of navigable rivers. The state's coastline contains many salt marshes and estuaries, as well as natural ports such as Georgetown and Charleston. An unusual feature of the coastal plain is a large number of Carolina bays, the origins of which are uncertain; the bays tend to be oval. The terrain is flat and the soil is composed of recent sediments such as sand and clay.
Areas with better drainage make excellent farmland. The natural areas of the coastal plain are part of the Middle Atlantic coastal forests ecoregion. Just west of the coastal plain is the Sandhills region; the Sandhills are remnants of coastal dunes from a time when the land was sunken or the oceans were higher. The Upstate region contains the roots of an eroded mountain chain, it is hilly, with thin, stony clay soils, contains few areas suitable for farming. Much of the Piedmont was once farmed. Due to the changing economics of farming, much of the land is now reforested in Loblolly pine for the lumber industry; these forests are part of the Southeastern mixed forests ecoregion. At the southeastern edge of the Piedmont is the fall line, where rivers drop to the coastal plain; the fall line was an important early source of water power. Mills built to harness this resource encouraged the growth of several cities, including the capital, Columbia; the larger rivers are navigable up to the fall line. The northwestern part of the Piedmont is known as the Foothills.
The Cherokee Parkway is a scenic driving route through this area. This is. Highest in elevation is the Blue Ridge Region, containing an escarpment of the Blue Ridge Mountains, which continue into North Carolina and Georgia, as part of the southern Appalachian Mountains. Sassafras Mountain, South Carolina's highest point at 3,560 feet, is in this area. In this area is Caesars Head State Park; the environment here is that of the Appalachian-Blue Ridge forests ecoregion. The Chattooga River, on the border between South Carolina and Georgia, is a favorite whitewater rafting destination. South Carolina has several major lakes covering over 683 square miles. All major lakes in South Carolina are man-made; the following are the lakes listed by size. Lake Marion 110,000 acres Lake Strom Thurmond 71,100 acres Lake Moultrie 60,000 acres Lake Hartwell 56,000 acres Lake Murray 50,000 acres Russell Lake 26,650 acres Lake Keowee 18,372 acres Lake Wylie 13,400 acres Lake Wateree 13,250 acres Lake Greenwood 11,400 acres Lake Jocassee 7,500 acres Lake Bowen Earthquakes in South Carolina demonstrate the greatest frequency along the central coastline of the state, in the Charleston area.
South Carolina averages 10–15 earthquakes a year below magnitude 3. The Charleston Earthquake of 1886 was the largest quake to hit the Southeastern United States; this 7.2 magnitude earthquake destroyed much of the city. Faults in this region are difficult to study at the surface due to thick sedimentation on top of them. Many of the ancient faults are within plates rather than along plate boundaries. South Carolina has a humid subtropical climate, although high-elevation areas in the Upstate area have fewer subtropical characteristics than areas on the Atlantic coastline. In the summer, South Carolina is hot and humid, with daytime temperatures averaging between 86–93 °F in most of the state and overnight lows averaging 70–75 °F on the coast and from 66–73 °F inland. Winter temperatures are much less uniform in South Carolina. Coastal areas of the state have mild winters, with high temperatures approaching an average of 60 °F and overnight lows around 40 °F. Inland, the average January overnight low is around 32 °F i
Hartwell Dam is a concrete and embankment dam located on the Savannah River at the border of South Carolina and Georgia, creating Lake Hartwell. The dam was built by the U. S. Army Corps of Engineers between 1955 and 1962 for the purposes of flood control and navigation; the concrete and earthen structure spans 15,840 feet. The concrete section rises 204 feet above the riverbed at its apex; the Hartwell Dam produces 468 million KWh of electricity annually, has prevented over $40 million in flood damage since completion and provides recreation, water quality, water supply, along with fish and wildlife management. In 1890, Lieutenant Oberlin M. Carter of the U. S. Army Corps of Engineers Savannah Office issued a survey report that recommended the construction of dams on the Savannah River in order to prevent flooding in Augusta, Georgia, his report was overlooked until the 1927 Rivers and Harbors Act allowed the USACE to investigate development of the Savannah River for the purpose of hydroelectricity, flood control and irrigation.
In 1933, the USACE completed the report for the entire Savannah River Basin that recommended against government flood control development of the basin but did propose two hydropower dams in the upper Savannah Basin, the Hartwell and Clark Hill dams. The Flood Control Act of 1950 authorized the Hartwell Dam and Reservoir as a development project of the Savannah River Basin. Construction on the dam began in 1955 and the plan called for a 3-mile long structure containing four hydroelectric generators with a combined 264 MW capacity. Predicting future demand requirements, the ability to install a fifth generator in the future was provided. 1,900 ft of the dam's length consists of the rest compacted earth. A year before completion, in February 1961, the dam began to inundate a portion of the Savannah River to create the reservoir. In March 1962, the reservoir was complete behind the dam and the four original hydro-power generators went online in April; the original projected cost of the dam was $68.4 million USD but when completed was just over $89.2 million USD.
In 1983, the fifth generator was installed on the dam, raising the generation capacity to 344 MW. By 1997, the four original generators had exceeded their 30-year life expectancy by seven years and underwent a rehabilitation. Phase 1 began in 1997 and consisted of generator rewinding/turbine refurbishment and upgrading circuit breakers, replacing and upgrading the transformers. Phase II consisted of replacing all of the switch-yard breakers and bus-work and updating the powerhouse and Clemson Pumping Station. Upon completion of the rehabilitation, generation capacity was increased to 422 MW, a 22.7% increase. In June 2007, drought triggered Level 1 conditions, resulting in reduced flows of 4,200 cubic feet per second. 2 months in August, Level 2 was triggered, resulting in a 4,000 cu ft/s release. After receiving federal and state agency authorization, the flow was again reduced to 3,600 cu ft/s in October 2007. In August 2008, to maintain mid-term hydroelectric output and reservoir levels, releases below 3,600 cu ft/s were explored and temporarily implemented.
The flows were increased back to 3600 feet sec in February 2009 to prevent environmental damage. In October 2009, the Savannah River Basin transitioned out of drought and normal flows should soon resume; the 2007-2009 drought raised controversy over the Southeastern Power Association's role of controlling the Hartwell Dam. Complaints arose that the dam was releasing excess water in order to provide cheap power to communities. In addition, environmental controversy arose as to whether the releases and subsequent draining of the reservoir during a severe drought was necessary. USACE Hartwell Dam and Lake
Hydroelectricity is electricity produced from hydropower. In 2015, hydropower generated 16.6% of the world's total electricity and 70% of all renewable electricity, was expected to increase about 3.1% each year for the next 25 years. Hydropower is produced in 150 countries, with the Asia-Pacific region generating 33 percent of global hydropower in 2013. China is the largest hydroelectricity producer, with 920 TWh of production in 2013, representing 16.9 percent of domestic electricity use. The cost of hydroelectricity is low, making it a competitive source of renewable electricity; the hydro station consumes no water, unlike gas plants. The average cost of electricity from a hydro station larger than 10 megawatts is 3 to 5 U. S. cents per kilowatt hour. With a dam and reservoir it is a flexible source of electricity since the amount produced by the station can be varied up or down rapidly to adapt to changing energy demands. Once a hydroelectric complex is constructed, the project produces no direct waste, in many cases, has a lower output level of greenhouse gases than fossil fuel powered energy plants.
Hydropower has been used since ancient times to perform other tasks. In the mid-1770s, French engineer Bernard Forest de Bélidor published Architecture Hydraulique which described vertical- and horizontal-axis hydraulic machines. By the late 19th century, the electrical generator was developed and could now be coupled with hydraulics; the growing demand for the Industrial Revolution would drive development as well. In 1878 the world's first hydroelectric power scheme was developed at Cragside in Northumberland, England by William Armstrong, it was used to power a single arc lamp in his art gallery. The old Schoelkopf Power Station No. 1 near Niagara Falls in the U. S. side began to produce electricity in 1881. The first Edison hydroelectric power station, the Vulcan Street Plant, began operating September 30, 1882, in Appleton, with an output of about 12.5 kilowatts. By 1886 there were 45 hydroelectric power stations in the U. S. and Canada. By 1889 there were 200 in the U. S. alone. At the beginning of the 20th century, many small hydroelectric power stations were being constructed by commercial companies in mountains near metropolitan areas.
Grenoble, France held the International Exhibition of Hydropower and Tourism with over one million visitors. By 1920 as 40% of the power produced in the United States was hydroelectric, the Federal Power Act was enacted into law; the Act created the Federal Power Commission to regulate hydroelectric power stations on federal land and water. As the power stations became larger, their associated dams developed additional purposes to include flood control and navigation. Federal funding became necessary for large-scale development and federally owned corporations, such as the Tennessee Valley Authority and the Bonneville Power Administration were created. Additionally, the Bureau of Reclamation which had begun a series of western U. S. irrigation projects in the early 20th century was now constructing large hydroelectric projects such as the 1928 Hoover Dam. The U. S. Army Corps of Engineers was involved in hydroelectric development, completing the Bonneville Dam in 1937 and being recognized by the Flood Control Act of 1936 as the premier federal flood control agency.
Hydroelectric power stations continued to become larger throughout the 20th century. Hydropower was referred to as white coal for its plenty. Hoover Dam's initial 1,345 MW power station was the world's largest hydroelectric power station in 1936; the Itaipu Dam opened in 1984 in South America as the largest, producing 14,000 MW but was surpassed in 2008 by the Three Gorges Dam in China at 22,500 MW. Hydroelectricity would supply some countries, including Norway, Democratic Republic of the Congo and Brazil, with over 85% of their electricity; the United States has over 2,000 hydroelectric power stations that supply 6.4% of its total electrical production output, 49% of its renewable electricity. The technical potential for hydropower development around the world is much greater than the actual production: the percent of potential hydropower capacity that has not been developed is 71% in Europe, 75% in North America, 79% in South America, 95% in Africa, 95% in the Middle East, 82% in Asia-Pacific.
The political realities of new reservoirs in western countries, economic limitations in the third world and the lack of a transmission system in undeveloped areas result in the possibility of developing 25% of the remaining technically exploitable potential before 2050, with the bulk of that being in the Asia-Pacific area. Some countries have developed their hydropower potential and have little room for growth: Switzerland produces 88% of its potential and Mexico 80%. Most hydroelectric power comes from the potential energy of dammed water driving a water turbine and generator; the power extracted from the water depends on the volume and on the difference in height between the source and the water's outflow. This height difference is called the head. A large pipe delivers water from the reservoir to the turbine; this method produces electricity to supply high peak demands by moving water between reservoirs at different elevations. At times of low electrical demand, the excess generation capacity is used to pump water into the higher reservoir.
When the demand becomes greater, water is released back into the lower reservoir through a turbine. Pumped-storage schemes provide the most commercially important means of large-scale grid energy storage and improve the daily capacity factor of the generation system. Pumped storag
United States Army Corps of Engineers
The United States Army Corps of Engineers is a U. S. federal agency under the Department of Defense and a major Army command made up of some 37,000 civilian and military personnel, making it one of the world's largest public engineering and construction management agencies. Although associated with dams and flood protection in the United States, USACE is involved in a wide range of public works throughout the world; the Corps of Engineers provides outdoor recreation opportunities to the public, provides 24% of U. S. hydropower capacity. The corps' mission is to "Deliver vital military engineering services. Other civil engineering projects include flood control, beach nourishment, dredging for waterway navigation. Design and construction of flood protection systems through various federal mandates. Design and construction management of military facilities for the Army, Air Force, Army Reserve and Air Force Reserve and other Defense and Federal agencies. Environmental regulation and ecosystem restoration.
The history of United States Army Corps of Engineers can be traced back to 16 June 1775, when the Continental Congress organized an army with a chief engineer and two assistants. Colonel Richard Gridley became General George Washington's first chief engineer. One of his first tasks was to build fortifications near Boston at Bunker Hill; the Continental Congress recognized the need for engineers trained in military fortifications and asked the government of King Louis XVI of France for assistance. Many of the early engineers in the Continental Army were former French officers. Louis Lebègue Duportail, a lieutenant colonel in the French Royal Corps of Engineers, was secretly sent to America in March 1777 to serve in Washington's Continental Army. In July 1777 he was appointed colonel and commander of all engineers in the Continental Army, in November 17, 1777, he was promoted to brigadier general; when the Continental Congress created a separate Corps of Engineers in May 1779 Duportail was designated as its commander.
In late 1781 he directed the construction of the allied U. S.-French siege works at the Battle of Yorktown. From 1794 to 1802 the engineers were combined with the artillery as the Corps of Artillerists and Engineers; the Corps of Engineers, as it is known today, came into existence on 16 March 1802, when President Thomas Jefferson signed the Military Peace Establishment Act whose aim was to "organize and establish a Corps of Engineers... that the said Corps... shall be stationed at West Point in the State of New York and shall constitute a military academy." Until 1866, the superintendent of the United States Military Academy was always an officer of engineer. The General Survey Act of 1824 authorized the use of Army engineers to survey canal routes; that same year, Congress passed an "Act to Improve the Navigation of the Ohio and Mississippi Rivers" and to remove sand bars on the Ohio and "planters, sawyers, or snags" on the Mississippi, for which the Corps of Engineers was the responsible agency.
Separately authorized on 4 July 1838, the U. S. Army Corps of Topographical Engineers consisted only of officers and was used for mapping and the design and construction of federal civil works and other coastal fortifications and navigational routes, it was merged with the Corps of Engineers on 31 March 1863, at which point the Corps of Engineers assumed the Lakes Survey District mission for the Great Lakes. In 1841, Congress created the Lake Survey; the survey, based in Detroit, Mich. was charged with conducting a hydrographical survey of the Northern and Northwestern Lakes and preparing and publishing nautical charts and other navigation aids. The Lake Survey published its first charts in 1852. In the mid-19th century, Corps of Engineers' officers ran Lighthouse Districts in tandem with U. S. Naval officers; the Army Corps of Engineers played a significant role in the American Civil War. Many of the men who would serve in the top leadership in this institution were West Point graduates who rose to military fame and power during the Civil War.
Some of these men were Union Generals George McClellan, Henry Halleck, George Meade, Confederate generals Robert E. Lee, Joseph Johnston, P. G. T. Beauregard; the versatility of officers in the Army Corps of Engineers contributed to the success of numerous missions throughout the Civil War. They were responsible for building pontoon and railroad bridges and batteries, the destruction of enemy supply lines, the construction of roads; the Union forces were not the only ones to employ the use of engineers throughout the war, on 6 March 1861, once the South had seceded from the Union, among the different acts passed at the time, a provision was included that called for the creation of a Confederate Corps of Engineers. The progression of the war demonstrated the South's disadvantage in engineering expertise. To overcome this obstacle, the Confederate Congress passed legislation that gave a company of engineers to every division in the field. One of the main projects for the Army Corps of Engineers was constructing railroads and bridges, which Union forces took advantage of because railroads and bridges provided access to resources and industry.
One area where the Confederate engineers were able to outperform the Union Army was in the ability to build fortification