1.
Mississippi River
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The Mississippi River is the chief river of the largest drainage system on the North American continent. Flowing entirely in the United States, it rises in northern Minnesota, with its many tributaries, the Mississippis watershed drains all or parts of 31 U. S. states and 2 Canadian provinces between the Rocky and Appalachian Mountains. The Mississippi ranks as the fourth longest and fifteenth largest river in the world by discharge, the river either borders or passes through the states of Minnesota, Wisconsin, Iowa, Illinois, Missouri, Kentucky, Tennessee, Arkansas, Mississippi, and Louisiana. Native Americans long lived along the Mississippi River and its tributaries, most were hunter-gatherers, but some, such as the Mound Builders, formed prolific agricultural societies. The arrival of Europeans in the 16th century changed the way of life as first explorers, then settlers. The river served first as a barrier, forming borders for New Spain, New France, and the early United States, and then as a vital transportation artery and communications link. Formed from thick layers of the silt deposits, the Mississippi embayment is one of the most fertile agricultural regions of the country. In recent years, the river has shown a shift towards the Atchafalaya River channel in the Delta. The word itself comes from Messipi, the French rendering of the Anishinaabe name for the river, see below in the History section for additional information. In addition to historical traditions shown by names, there are at least two measures of a rivers identity, one being the largest branch, and the other being the longest branch. Using the largest-branch criterion, the Ohio would be the branch of the Lower Mississippi. Using the longest-branch criterion, the Middle Mississippi-Missouri-Jefferson-Beaverhead-Red Rock-Hellroaring Creek River would be the main branch and its length of at least 3,745 mi is exceeded only by the Nile, the Amazon, and perhaps the Yangtze River among the longest rivers in the world. The source of this waterway is at Browers Spring,8,800 feet above sea level in southwestern Montana and this is exemplified by the Gateway Arch in St. Louis and the phrase Trans-Mississippi as used in the name of the Trans-Mississippi Exposition. It is common to qualify a regionally superlative landmark in relation to it, the New Madrid Seismic Zone along the river is also noteworthy. These various basic geographical aspects of the river in turn underlie its human history and present uses of the waterway, the Upper Mississippi runs from its headwaters to its confluence with the Missouri River at St. Louis, Missouri. The source of the Upper Mississippi branch is traditionally accepted as Lake Itasca,1,475 feet above sea level in Itasca State Park in Clearwater County, however, the lake is in turn fed by a number of smaller streams. From its origin at Lake Itasca to St. Louis, Missouri, fourteen of these dams are located above Minneapolis in the headwaters region and serve multiple purposes, including power generation and recreation. The remaining 29 dams, beginning in downtown Minneapolis, all locks and were constructed to improve commercial navigation of the upper river
2.
Kaskaskia, Illinois
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Kaskaskia is a historically important village in Randolph County, Illinois, United States. In the 2010 census the population was 14, making it the second-smallest incorporated community in the State of Illinois in terms of population, behind Valley City. As a major French colonial town of the Illinois Country, in the 18th century its population was about 7,000. During the American Revolutionary War, the town, which by then had become a center for the British Province of Quebec, was taken by the Virginia militia during the Illinois campaign. It was designated as the county seat of Illinois County, Virginia, Kaskaskia was later named as the capital of the United States Illinois Territory, created on February 3,1809. In 1818, when Illinois became the 21st U. S. state, the town served as the states first capital until 1819. Most of the town was destroyed in April 1881 by flooding, as the Mississippi River shifted eastward to a new channel and this resulted from deforestation of the river banks during the 19th century, due to crews taking wood for fuel to feed the steamboat and railroad traffic. The river now passes east rather than west of the town, the state boundary line, however, remained in its original location. Accordingly, if the Mississippi River is considered to be a break in continuity, Kaskaskia is an exclave of Illinois, lying west of the Mississippi. A small bridge crosses the old riverbed, now a creek that is filled with water during flood season. Kaskaskia has an Illinois telephone area code and a Missouri ZIP Code and its roads are maintained by Illinois Dept. of Transportation, and its few residents vote in the Illinois elections. The town was evacuated in the Great Flood of 1993, which covered it with more than nine feet deep. In 2010, How the States Got Their Shapes on the History Channel featured Kaskaskia, the former Randolph County Sheriff was featured discussing different sites on Kaskaskia Island. The site of Kaskaskia near the river was first a Native American village, the historic Illini peoples lived in this area at the time of European encounter and traded with the French colonists. In 1703, French Jesuit missionaries established a mission with the goal of converting the Illini Native Americans to Catholicism, the congregation built its first stone church in 1714. The French also had a fur trading post in the village, Canadien settlers moved in to farm and to exploit the lead mines on the Missouri side of the river. Favorably situated on a peninsula on the east side of the Mississippi River, Kaskaskia became the capital of Upper Louisiana and the French built Fort de Chartres nearby in 1718. In the same year they imported the first enslaved Africans, shipped from Santo Domingo in the Caribbean, from the years of early French settlement, Kaskaskia was a multicultural village, consisting of a few French men and numerous Illinois and other American Indians
3.
Great Flood of 1993
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The Great Mississippi and Missouri Rivers Flood of 1993 occurred in the American Midwest, along the Mississippi and Missouri rivers and their tributaries, from April to October 1993. The flood was among the most costly and devastating to ever occur in the United States, the hydrographic basin affected cover around 745 miles in length and 435 miles in width, totaling about 320,000 square miles. In some categories, the 1993 flood even surpassed the 1927 flood and this weather pattern persisted throughout the following autumn. During the winter of 1992–93, the region experienced heavy snowfall and these conditions were followed by persistent spring weather patterns that produced storms over the same locations. Soils across much of the area were saturated by June 1, with additional rainfall all running off into streams and rivers. These wet-weather conditions contrasted sharply with the droughts and heat waves experienced in the southeastern United States, storms, persistent and repetitive in nature during the late spring and summer, bombarded the Upper Midwest with voluminous rainfall. Portions of east-central Iowa received as much as 48 inches of rain between April 1 and August 31,1993, and many areas across the plains had precipitation 400–750% above normal. In the St. Louis National Weather Service forecast area encompassing eastern Missouri and southwest Illinois,36 forecast points rose above flood stage, the 1993 flood broke record river levels set during the 1973 Mississippi and the 1951 Missouri River floods. Civil Air Patrol crews from 21 states served more than 5,000 meals to victims and volunteers. Over 1,000 flood warnings and statements, five times the normal, were issued to notify the public, in such places as St. Louis, river levels were nearly 20 feet above flood stage, the highest ever recorded there in 228 years. The 52-foot -high St. Louis Floodwall, built to handle the volume of the 1844 flood, was able to keep the 1993 flood out with just over two feet to spare. This floodwall was built in the 1960s, to great controversy, had it been breached, the whole of downtown St. Louis would have been submerged. Emergency officials estimated that all of the 700 privately built agricultural levees were overtopped or destroyed along the Missouri River. Navigation on the Mississippi and Missouri River had been closed since early July resulting in a loss of $2 million per day in commerce. In an attempt to strand his wife on the side of the river so he could continue partying. The breach flooded 14,000 acres of farmland, destroyed buildings, the Redwood River in Minnesota began experiencing severe flooding in May. On May 22, Sioux Falls, South Dakota, received 7.5 inches of rain in a three-hour period, from May through July, Sioux Falls, South Dakota received 22.55 inches of rain, the wettest three-month period in its history. As noted above, rains in South Dakota contributed to flooding downstream, in June, flooding occurred along the Black River in Wisconsin, with flooding also starting to occur along the Mississippi, Missouri, and Kansas rivers
4.
Flood
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A flood is an overflow of water that submerges land which is usually dry. The European Union Floods Directive defines a flood as a covering by water of land not normally covered by water, in the sense of flowing water, the word may also be applied to the inflow of the tide. Floods can also occur in rivers when the flow exceeds the capacity of the river channel. Floods often cause damage to homes and businesses if they are in the flood plains of rivers. Some floods develop slowly, while others such as floods, can develop in just a few minutes. Additionally, floods can be local, impacting a neighborhood or community, or very large, the word flood comes from the Old English flod, a word common to Germanic languages. Deluge myths are stories of a great flood sent by a deity or deities to destroy civilization as an act of divine retribution. Floods can happen on flat or low-lying areas when water is supplied by rainfall or snowmelt more rapidly than it can infiltrate or run off. The excess accumulates in place, sometimes to hazardous depths, surface soil can become saturated, which effectively stops infiltration, where the water table is shallow, such as a floodplain, or from intense rain from one or a series of storms. Infiltration also is slow to negligible through frozen ground, rock, concrete, paving, areal flooding begins in flat areas like floodplains and in local depressions not connected to a stream channel, because the velocity of overland flow depends on the surface slope. Endorheic basins may experience flooding during periods when precipitation exceeds evaporation. Floods occur in all types of river and stream channels, from the smallest ephemeral streams in humid zones to normally-dry channels in arid climates to the worlds largest rivers. When overland flow occurs on tilled fields, it can result in a flood where sediments are picked up by run off. Localized flooding may be caused or exacerbated by drainage obstructions such as landslides, ice, debris, slow-rising floods most commonly occur in large rivers with large catchment areas. The increase in flow may be the result of sustained rainfall, rapid snow melt, monsoons, the cause may be localized convective precipitation or sudden release from an upstream impoundment created behind a dam, landslide, or glacier. In one instance, a flood killed eight people enjoying the water on a Sunday afternoon at a popular waterfall in a narrow canyon. Without any observed rainfall, the rate increased from about 50 to 1,500 cubic feet per second in just one minute. Two larger floods occurred at the site within a week
5.
Water
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Water is a transparent and nearly colorless chemical substance that is the main constituent of Earths streams, lakes, and oceans, and the fluids of most living organisms. Its chemical formula is H2O, meaning that its molecule contains one oxygen, Water strictly refers to the liquid state of that substance, that prevails at standard ambient temperature and pressure, but it often refers also to its solid state or its gaseous state. It also occurs in nature as snow, glaciers, ice packs and icebergs, clouds, fog, dew, aquifers, Water covers 71% of the Earths surface. It is vital for all forms of life. Only 2. 5% of this water is freshwater, and 98. 8% of that water is in ice and groundwater. Less than 0. 3% of all freshwater is in rivers, lakes, and the atmosphere, a greater quantity of water is found in the earths interior. Water on Earth moves continually through the cycle of evaporation and transpiration, condensation, precipitation. Evaporation and transpiration contribute to the precipitation over land, large amounts of water are also chemically combined or adsorbed in hydrated minerals. Safe drinking water is essential to humans and other even though it provides no calories or organic nutrients. There is a correlation between access to safe water and gross domestic product per capita. However, some observers have estimated that by 2025 more than half of the population will be facing water-based vulnerability. A report, issued in November 2009, suggests that by 2030, in developing regions of the world. Water plays an important role in the world economy, approximately 70% of the freshwater used by humans goes to agriculture. Fishing in salt and fresh water bodies is a source of food for many parts of the world. Much of long-distance trade of commodities and manufactured products is transported by boats through seas, rivers, lakes, large quantities of water, ice, and steam are used for cooling and heating, in industry and homes. Water is an excellent solvent for a variety of chemical substances, as such it is widely used in industrial processes. Water is also central to many sports and other forms of entertainment, such as swimming, pleasure boating, boat racing, surfing, sport fishing, Water is a liquid at the temperatures and pressures that are most adequate for life. Specifically, at atmospheric pressure of 1 bar, water is a liquid between the temperatures of 273.15 K and 373.15 K
6.
Floodplain
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In other words, a floodplain is an area near a river or a stream which floods when the water level reaches flood stage. Flood plains are made by a meander eroding sideways as it travels downstream, when a river breaks its banks and floods, it leaves behind layers of alluvium. These gradually build up to create the floor of the flood plain, floodplains generally contain unconsolidated sediments, often extending below the bed of the stream. These are accumulations of sand, gravel, loam, silt, and/or clay, and are often important aquifers, geologically ancient floodplains are often represented in the landscape by fluvial terraces. These are old floodplains that remain relatively high above the present floodplain and it is probable that any section of such an alluvial plain would show deposits of a similar character. The floodplain during its formation is marked by meandering or anastomotic streams, oxbow lakes and bayous, marshes or stagnant pools, and is occasionally completely covered with water. When the drainage system has ceased to act or is diverted for any reason. The floodplain differs, however, because it is not altogether flat and it has a gentle slope downstream, and often, for a distance, from the side towards the center. The floodplain is the place for a river to dissipate its energy. Meanders form over the floodplain to slow down the flow of water, in terms of flood management the upper part of the floodplain is crucial as this is where the flood water control starts. Artificial canalisation of the river here will have a impact on wider flooding. This is the basis of flood management. Floodplains can support particularly rich ecosystems, both in quantity and diversity, tugay forests form an ecosystem associated with floodplains, especially in Central Asia. They are a category of riparian zones or systems, a floodplain can contain 100 or even 1,000 times as many species as a river. Microscopic organisms thrive and larger species enter a rapid breeding cycle, opportunistic feeders move in to take advantage. The production of nutrients peaks and falls away quickly, however the surge of new growth endures for some time and this makes floodplains particularly valuable for agriculture. River flow rates are undergoing change following suit with climate change and this change is a threat to the riparian zones and other flood plain forests. These forests have over time synced their seedling deposits after the peaks in flow to best take advantage of the nutrient rich soil generated by peak flow
7.
Environment Agency
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The Environment Agencys stated purpose is, to protect or enhance the environment, taken as a whole so as to promote the objective of achieving sustainable development. Protection of the environment relates to such as flood and pollution. The vision of the Agency is of a rich, healthy and diverse environment for present and it is organised into eight directorates that report to the chief executive. There are two policy and process directorates, one deals with Flood and Coastal Risk Management and the other with Environment and Business. These are backed up by the Evidence directorate, the fourth directorate is a single Operations delivery unit, responsible for national services, and line management of all the Regional and Area staff. The remaining directorates are central shared service groups for Finance, Legal Services, Resources, in support of its aims, the Agency acts as an operating authority, a regulatory authority and a licence authority. The agency is funded in part from the UK government Department for Environment, Food, funding for asset management and improvement and acquisition of flood risk management assets has traditionally come from local authorities via Flood Defence Committees. This was then effectively repaid by central Government in later years as part of the Formula Spending Share, in 2005 this was simplified by making a direct transfer from Treasury to the Environment Agency in the form of Flood Defence Grant in Aid. The Environment Agencys total funding in 2007–08 was £1,025 million, of that total, £628 million was provided in the form of flood defence grant-in-aid from government. In addition, £347 million was raised through statutory charging schemes and flood defence levies, in 2007–08 had an operational budget of £1.025 billion, of which £628m was grant from the Agencys sponsoring Government Departments. Approximately half the Agencys expenditure is on flood risk management, of the remainder, 12% goes to water resources, and 6% to other water functions including navigation and wildlife. Its chief executive is Sir James Bevan, Sir Philip Dilley resigned as chairman on 11 January 2016, with Emma Howard Boyd becoming acting chair. The Environment Agency was created by the Environment Act 1995, and it had responsibility for the whole of England and Wales but with specifically designated border arrangements with Scotland covering the catchment of the River Tweed. All of the bodies were disbanded and the local authorities relinquished their waste regulatory role. At the same time, the Agency took responsibility for issuing warnings to the public. On 1 April 2013, that part of the Environment Agency covering Wales was merged into Natural Resources Wales, the Environment Agency is the principal flood risk management operating authority. It has the power to flood risk from designated main rivers. These functions in relation to other rivers in England are undertaken by Local Authorities or internal drainage boards, the Environment Agency is also responsible for increasing public awareness of flood risk, flood forecasting and warning and has a general supervisory duty for flood risk management
8.
Tide
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Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon and the Sun and the rotation of the Earth. Some shorelines experience a semi-diurnal tide—two nearly equal high and low tides each day, other locations experience a diurnal tide—only one high and low tide each day. A mixed tide—two uneven tides a day, or one high, Tides vary on timescales ranging from hours to years due to a number of factors. To make accurate records, tide gauges at fixed stations measure water level over time, gauges ignore variations caused by waves with periods shorter than minutes. These data are compared to the level usually called mean sea level. Tidal phenomena are not limited to the oceans, but can occur in other systems whenever a gravitational field varies in time. For example, the part of the Earth is affected by tides. Tide changes proceed via the following stages, Sea level rises over several hours, covering the intertidal zone, the water rises to its highest level, reaching high tide. Sea level falls over several hours, revealing the intertidal zone, the water stops falling, reaching low tide. Oscillating currents produced by tides are known as tidal streams, the moment that the tidal current ceases is called slack water or slack tide. The tide then reverses direction and is said to be turning, slack water usually occurs near high water and low water. But there are locations where the moments of slack tide differ significantly from those of high, Tides are commonly semi-diurnal, or diurnal. The two high waters on a day are typically not the same height, these are the higher high water. Similarly, the two low waters each day are the low water and the lower low water. The daily inequality is not consistent and is small when the Moon is over the equator. From the highest level to the lowest, Highest Astronomical Tide – The highest tide which can be predicted to occur, note that meteorological conditions may add extra height to the HAT. Mean High Water Springs – The average of the two high tides on the days of spring tides, mean High Water Neaps – The average of the two high tides on the days of neap tides. Mean Sea Level – This is the sea level
9.
Storm surge
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Most casualties during tropical cyclones occur as the result of storm surges. The deadliest storm surge on record was the 1970 Bhola cyclone, the low-lying coast of the Bay of Bengal is particularly vulnerable to surges caused by tropical cyclones. The deadliest storm surge in the twenty-first century was caused by the Cyclone Nargis, the next deadliest in this century was caused by the Typhoon Haiyan, which killed more than 6,000 people in the central Philippines in 2013 and resulted in economic losses estimated at $14 billion. Louis, Diamondhead and Pass Christian in Mississippi, a high storm surge occurred in New York City from Hurricane Sandy in October 2012, with a high tide of 14 ft. The pressure effects of a tropical cyclone will cause the level in the open ocean to rise in regions of low atmospheric pressure. The rising water level will counteract the low pressure such that the total pressure at some plane beneath the water surface remains constant. This effect is estimated at a 10 mm increase in sea level for every millibar drop in atmospheric pressure, strong surface winds cause surface currents at a 45° angle to the wind direction, by an effect known as the Ekman Spiral. Wind stresses cause a phenomenon referred to as wind set-up, which is the tendency for water levels to increase at the downwind shore, intuitively, this is caused by the storm simply blowing the water towards one side of the basin in the direction of its winds. Because the Ekman Spiral effects spread vertically through the water, the effect is proportional to depth. The pressure effect and the wind set-up on an open coast will be driven into bays in the way as the astronomical tide. The Earths rotation causes the Coriolis effect, which bends currents to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. When this bend brings the currents into more contact with the shore it can amplify the surge. The effect of waves, while powered by the wind, is distinct from a storms wind-powered currents. Powerful wind whips up large, strong waves in the direction of its movement, although these surface waves are responsible for very little water transport in open water, they may be responsible for significant transport near the shore. When waves are breaking on a more or less parallel to the beach. The rainfall effect is experienced predominantly in estuaries, Hurricanes may dump as much as 12 in of rainfall in 24 hours over large areas, and higher rainfall densities in localized areas. As a result, watersheds can quickly surge water into the rivers that drain them and this can increase the water level near the head of tidal estuaries as storm-driven waters surging in from the ocean meet rainfall flowing from the estuary. This situation well exemplified by the southeast coast of Florida
10.
Wind wave
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In fluid dynamics, wind waves, or wind-generated waves, are surface waves that occur on the free surface of bodies of water. They result from the wind blowing over an area of fluid surface, Waves in the oceans can travel thousands of miles before reaching land. Wind waves on Earth range in size from small ripples, to waves over 100 ft high, when directly generated and affected by local winds, a wind wave system is called a wind sea. After the wind ceases to blow, wind waves are called swells, more generally, a swell consists of wind-generated waves that are not significantly affected by the local wind at that time. They have been generated elsewhere or some time ago, wind waves in the ocean are called ocean surface waves. Wind waves have an amount of randomness, subsequent waves differ in height, duration. The key statistics of wind waves in evolving sea states can be predicted with wind wave models, although waves are usually considered in the water seas of Earth, the hydrocarbon seas of Titan may also have wind-driven waves. The great majority of large breakers seen at a result from distant winds. Water depth All of these work together to determine the size of wind waves. Further exposure to that wind could only cause a dissipation of energy due to the breaking of wave tops. Waves in an area typically have a range of heights. For weather reporting and for analysis of wind wave statistics. This figure represents an average height of the highest one-third of the waves in a time period. The significant wave height is also the value a trained observer would estimate from visual observation of a sea state, given the variability of wave height, the largest individual waves are likely to be somewhat less than twice the reported significant wave height for a particular day or storm. Wave formation on a flat water surface by wind is started by a random distribution of normal pressure of turbulent wind flow over the water. This pressure fluctuation produces normal and tangential stresses in the surface water and it is assumed that, The water is originally at rest. There is a distribution of normal pressure to the water surface from the turbulent wind. Correlations between air and water motions are neglected, the second mechanism involves wind shear forces on the water surface
11.
Flood insurance
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Flood insurance denotes the specific insurance coverage against property loss from flooding. To determine risk factors for specific properties, insurers will often refer to maps that denote lowlands, floodplains. Nationwide, only 20% of American homes at risk for floods are covered by flood insurance. Most private insurers do not insure against the peril of flood due to the prevalence of adverse selection, in certain flood-prone areas, the federal government requires flood insurance to secure mortgage loans backed by federal agencies such as the FHA and VA. However, the program has never worked as insurance, because of adverse selection and it has never priced people out of living in very risky areas by charging an appropriate premium, instead, too few places are included in the must-insure category, and premiums are artificially low. The lack of insurance can be detrimental to many homeowners who may discover only after the damage has been done that their standard insurance policies do not cover flooding. Very few insurers in the US provide flood insurance coverage due to the hazard of flood typically being confined to a few areas. As a result, it is a risk due to the inability to spread the risk to a wide enough population in order to absorb the potential catastrophic nature of the hazard. In response to this, the government created the National Flood Insurance Program in 1968. The National Association of Insurance Commissioners found that 33 percent of U. S. heads of household still hold the belief that flood damage is covered by a standard homeowners policy. FEMA states that approximately 50% of low flood zone risk borrowers think they are ineligible, anyone residing in a community participating in the NFIP can buy flood insurance, even renters. Flood insurance may be available for residents of approximately 19,000 communities nationwide through the NFIP, usually, the British insurers require from clients living in Flood Risk Areas to flood-proof their homes or face much higher premiums and excesses. Home flood insurance doesnt exist in this country, says the Insurance Bureau of Canada, the insurance bureau defines a flood as water flowing overland and seeping in through windows, doors and cracks
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