vania-janet/multiturn-rag-retrieval-data huggingface dataset:
Timeline of Hurricane Katrina
By 11 : 00 AM CDT ( 1600 UTC ) , there was approximately 10 feet ( 3 m ) of water in St. Bernard Parish . Many rooftops could not be seen here as they were submerged . Therefore , there was much more than 10 feet ( 3.0 m ) of water in many places .
Hurricane Katrina
In Kentucky , a storm that had moved through the weekend before had already produced flooding and the rainfall from Katrina added to this . A 10 - year - old girl drowned in Hopkinsville . Dozens of business were closed and several families evacuated due to rising flood waters . As a result of the flooding , Kentucky Governor Ernie Fletcher declared three counties disaster areas and a statewide state of emergency . Additionally , wind gusts up to 72 mph ( 116 km / h ) resulted in some damage . Downed trees and power lines were reported in several counties in western Kentucky , especially Calloway and Christian counties . Overall , more than 10,000 utility customers in western Kentucky experienced power outages . The remnants of Katrina spawned a tornado in Virginia , damaging at least 13 homes in Marshall . In addition , approximately 4,000 people lost electricity . Over 3 in ( 76 mm ) of rain fell in portions of West Virginia , causing localized flooding in several counties . At least 103 homes and 7 buildings suffered some degree of water damage . A number of roads and bridges were inundated or washed out . The remnants of Katrina produced locally heavy precipitation in northeast Ohio , ranging from about 2 to 4 in ( 51 to 102 mm ) . Numerous streams and rivers overflowed their banks , forcing the closure of several roads , including Interstate 90 in Cleveland . Two deaths occurred due to a flood - related automobile accident in Huron County . Additionally , hundreds of homes and businesses suffered flood damage .
St. Johns River
The report also noted concerns about the District 's conclusion that the water withdrawals will have few deleterious ecological effects . This conclusion was based on the model findings that increased flows from upper basin projects and from changes in land use ( increases in impervious areas ) largely compensated for the impacts of water withdrawals on water flows and levels . Although the upper basin projects are positive insofar as they will return land to the basin ( and water to the river ) , the same can not be said about increased urban runoff , the poor quality of which is well known .
Drinking water supply and sanitation in the United States
Public service providers . Eighty - nine percent of Americans served by a public water system are served by a public or cooperative entity . Usually public systems are managed by utilities that are owned by a city or county , but have a separate legal personality , management and finances . Examples are the District of Columbia Water and Sewer Authority , the Los Angeles Department of Water and Power and Denver Water . In some cases public utilities span several jurisdictions . An example is the Washington Suburban Sanitary Commission that spans two counties in Maryland . Utility cooperatives are a major provider of water services , especially in small towns and rural areas
Meander
In the equilibrium theory , meanders decrease the stream gradient until an equilibrium between the erodibility of the terrain and the transport capacity of the stream is reached . A mass of water descending must give up potential energy , which , given the same velocity at the end of the drop as at the beginning , is removed by interaction with the material of the stream bed . The shortest distance ; that is , a straight channel , results in the highest energy per unit of length , disrupting the banks more , creating more sediment and aggrading the stream . The presence of meanders allows the stream to adjust the length to an equilibrium energy per unit length in which the stream carries away all the sediment that it produces .
Nephron
Considerable differences aid in distinguishing the descending and ascending limbs of the loop of Henle . The descending limb is permeable to water and noticeably less permeable to salt , and thus only indirectly contributes to the concentration of the interstitium . As the filtrate descends deeper into the hypertonic interstitium of the renal medulla , water flows freely out of the descending limb by osmosis until the tonicity of the filtrate and interstitium equilibrate . The hypertonicity of the medulla ( and therefore concentration of urine ) is determined in part by the size of the loop of Henle .
River Thames
Throughout early modern history the population of London and its industries discarded their rubbish in the river . This included the waste from slaughterhouses , fish markets , and tanneries . The buildup in household cesspools could sometimes overflow , especially when it rained , and was washed into London 's streets and sewers which eventually led to the Thames . In the late 18th and 19th centuries people known as Mudlarks scavenged in the river mud for a meagre living .
Hurricane Isaac (2012)
Louisiana Governor Bobby Jindal declared a state of emergency for Louisiana on August 26 . Later that day , reports of exposed levees in Louisiana began surfacing from local news outlets . Crews were reportedly dispatched to cover the exposed dirt with heavy plastic and fill gaps in the levees with Hesco bastions . A mandatory evacuation was ordered for St. Charles Parish and for the east bank of Plaquemines Parish and in Lafourche Parish below the Leon Theriot floodgates in Golden Meadow . 4,000 National Guard troops were activated in the state . The closure of all schools and Universities in South East Louisiana , including Louisiana State University followed Gov. Jindal 's State of Emergency declaration . Governor Jindal announced that he would not attend the 2012 Republican National Convention and would remain in his state to take care of storm - related problems . On August 27 , President Obama ordered federal aid to Louisiana to supplement state and local response efforts due to the emergency conditions resulting from Tropical Storm Isaac beginning on August 26 , 2012 . Governor Jindal on August 27 sent a letter to the Obama administration that the declaration fell short of the help he was requesting . Gov. Jindal had temporarily suspended Louisiana 's licensing requirements for emergency medical technicians , to let medical assistance officials from other states help Louisiana respond to Hurricane Isaac . Louisiana Commissioner of Administration Paul Rainwater announced that all state government offices would be closed August 29 . The US Army Corps of Engineers closed the Seabrook Floodgate and the IHNC Lake Borgne Surge Barrier to protect the New Orleans area from a storm surge . Mississippi
Tropical cyclone
Other approaches have been suggested over time , including cooling the water under a tropical cyclone by towing icebergs into the tropical oceans . Other ideas range from covering the ocean in a substance that inhibits evaporation , dropping large quantities of ice into the eye at very early stages of development ( so that the latent heat is absorbed by the ice , instead of being converted to kinetic energy that would feed the positive feedback loop ) , or blasting the cyclone apart with nuclear weapons . Project Cirrus even involved throwing dry ice on a cyclone . These approaches all suffer from one flaw above many others : tropical cyclones are simply too large and short - lived for any of the weakening techniques to be practical .
Catawba River
On October 3 , 2015 , Duke reported that a sinkhole had formed at the base of the Marshall Steam Station dam north of Charlotte on Lake Norman . The Department of Environmental Quality ( DEQ ) says Duke placed a liner in the hole and filled it with crushed stone .
Hoover Dam
The dam is protected against over-topping by two spillways . The spillway entrances are located behind each dam abutment , running roughly parallel to the canyon walls . The spillway entrance arrangement forms a classic side - flow weir with each spillway containing four 100 - foot - long ( 30 m ) and 16 - foot - wide ( 4.9 m ) steel - drum gates . Each gate weighs 5,000,000 pounds ( 2,300,000 kilograms ) and can be operated manually or automatically . Gates are raised and lowered depending on water levels in the reservoir and flood conditions . The gates could not entirely prevent water from entering the spillways but could maintain an extra 16 ft ( 4.9 m ) of lake level . Water flowing over the spillways falls dramatically into 600 - foot - long ( 180 m ) , 50 - foot - wide ( 15 m ) spillway tunnels before connecting to the outer diversion tunnels , and reentering the main river channel below the dam . This complex spillway entrance arrangement combined with the approximate 700 - foot ( 210 m ) elevation drop from the top of the reservoir to the river below was a difficult engineering problem and posed numerous design challenges . Each spillway 's capacity of 200,000 cu ft / s ( 5,700 m / s ) was empirically verified in post-construction tests in 1941 .
Indus River
In November 2011 , satellite images showed that the Indus river had re-entered India , feeding Great Rann of Kutch , Little Rann of Kutch and a lake near Ahmedabad known as Nal Sarovar . Heavy rains had left the river basin along with the Lake Manchar , Lake Hemal and Kalri Lake ( all in modern - day Pakistan ) inundated . This happened two centuries after the Indus river shifted its course westwards following the 1819 Rann of Kutch earthquake .
Tropical cyclone
The three - dimensional wind field in a tropical cyclone can be separated into two components : a `` primary circulation '' and a `` secondary circulation '' . The primary circulation is the rotational part of the flow ; it is purely circular . The secondary circulation is the overturning ( in - up - out - down ) part of the flow ; it is in the radial and vertical directions . The primary circulation is larger in magnitude , dominating the surface wind field , and is responsible for the majority of the damage a storm causes , while the secondary circulation is slower but governs the energetics of the storm .
Addicks Reservoir
On August 28 , 2017 during flooding from Hurricane Harvey , the U.S. Army Corps of Engineers began controlled water releases at both the Addicks and Barker Reservoirs , in an attempt to manage flood levels in the immediate area . The waters continued to rise , and on August 29 , after reaching pool elevation over 108 feet above NAVD 1988 , the Addicks Reservoir began around the end of the dam near Tanner Rd . Flows less than 100 cubic feet per second were detected at the spillway . In the afternoon of August 29 , 2017 , the Army Corps of Engineers made the decision to raise the controlled release rates to 16,000 cubic feet per second . As of August 30 , 2017 , combined controlled discharge rates of Barker and Addicks were 13,700 cubic feet per second , and subdivisions surrounding the outlets and downstream past Beltway 8 experienced significantly increased flooding as Buffalo Bayou further overtopped its banks .
Environmental issues in the Philippines
Only 5 % of the total population is connected to a sewer network . The vast majority uses flush toilets connected to septic tanks . Since sludge treatment and disposal facilities are rare , most effluents are discharged without treatment . According to the Asian Development Bank , the Pasig River is one of the world 's most polluted rivers . In March 2008 , Manila Water announced that a wastewater treatment plant will be constructed in Taguig . The first Philippine constructed wetland serving about 700 households was completed in 2006 in a peri-urban area of Bayawan City which has been used to resettle families that lived along the coast in informal settlements and had no access to safe water supply and sanitation facilities .
Hurricane Katrina
In Canada , the remnants of Katrina brought rainfall amounts in excess of 3.94 in ( 100 mm ) to many locations between the Niagara Peninsula and the Saint Lawrence River valley . Severe local flooding occurred in Quebec , forcing the evacuations of dozens of homes in some communities as rivers began overflowing their banks and sewage systems were becoming overwhelmed by the influx of precipitation . Inundated and washed out roads , including Route 138 along the north shore of the Saint Lawrence River , Route 172 north of Tadoussac , and Route 385 near Forestville left several communities isolated for at least a week .
Rainwater harvesting
In 1992 , American artist Michael Jones McKean created an artwork in Omaha , Nebraska , at the Bemis Center for Contemporary Art that created a fully sustainable rainbow in the Omaha skyline . The project collected thousands of gallons of rainwater , storing the water in six daisy - chained 12,000 gallons tanks . The massive logistical undertaking , during its five - month span , was one of the largest urban rainwater harvesting sites in the American Midwest .
Hurricane Harvey
Late on August 27 , a mandatory evacuation was issued for all of Bay City as model projections indicated the downtown area would be inundated by 10 ft ( 3.0 m ) of water . Flooding was anticipated to cut off access to the city around 1 : 00 p.m. CDT on August 28 . Evacuations took place in Conroe on August 28 following release of water from the Lake Conroe dam . On the morning on August 29 , a levee along Columbia Lakes in Brazoria County was breached , prompting officials to urgently request for everyone in the area to evacuate .
Hoover Dam
Before water from Lake Mead reaches the turbines , it enters the intake towers and then four gradually narrowing penstocks which funnel the water down towards the powerhouse . The intakes provide a maximum hydraulic head ( water pressure ) of 590 ft ( 180 m ) as the water reaches a speed of about 85 mph ( 140 km / h ) . The entire flow of the Colorado River passes through the turbines . The spillways and outlet works ( jet - flow gates ) are rarely used . The jet - flow gates , located in concrete structures 180 feet ( 55 m ) above the river , and also at the outlets of the inner diversion tunnels at river level , may be used to divert water around the dam in emergency or flood conditions , but have never done so , and in practice are only used to drain water from the penstocks for maintenance . Following an uprating project from 1986 to 1993 , the total gross power rating for the plant , including two 2.4 megawatt Pelton turbine - generators that power Hoover Dam 's own operations is a maximum capacity of 2080 megawatts . The annual generation of Hoover Dam varies . The maximum net generation was 10.348 TWh in 1984 , and the minimum since 1940 was 2.648 TWh in 1956 . The average power generated was 4.2 TWh / year for 1947 -- 2008 . In 2015 , the dam generated 3.6 TWh .
Rainwater harvesting
More development and knowledge is required to understand the benefits of rainwater harvesting that can provide to agriculture . Many countries , especially those with arid environments , use rainwater harvesting as a cheap and reliable source of clean water . To enhance irrigation in arid environments , ridges of soil are constructed to trap and prevent rainwater from running down hills and slopes . Even in periods of low rainfall , enough water is collected for crops to grow . Water can be collected from roofs , and dams and ponds can be constructed to hold large quantities of rainwater so that even on days when little to no rainfall occurs , enough is available to irrigate crops .
Sinking of the RMS Titanic
Lightoller opted to abandon his post to escape the growing crowds , and dived into the water from the roof of the officers ' quarters . He was sucked into the mouth of a ventilation shaft but was blown clear by `` a terrific blast of hot air '' and emerged next to the capsized lifeboat . The forward funnel collapsed under its own weight , crushing several people as it fell into the water and only narrowly missing the lifeboat . It closely missed Lightoller and created a wave that washed the boat 50 yards ( 46 m ) clear of the sinking ship . Those still on Titanic felt her structure shuddering as it underwent immense stresses . As first - class passenger Jack Thayer described it :
Geography of Chicago
North of the city of Chicago , there are steep bluffs and ravines that run along Lake Michigan . In contrast , south of the city of Chicago into Northwest Indiana it is without bluffs , but instead has sand dunes . The greatest example of these can be seen at Indiana Dunes National Lakeshore , where some dunes reach up to almost 200 feet . Farther inland , a series of moraines surrounds the Chicago Plain . This surrounding area is hilly and higher than the Chicago Plain . Past the moraines , the land flattens out again , but is interspersed with a few deep river valleys such as the Illinois River , Fox River , Des Plaines River , and Kankakee River . Here you may find rock cliffs and rock ravines , which are absent from the interior Chicago area ( the ravines of the north shore and south suburbs are soil ravines without any rock ) . City
Hurricane Katrina
An oil rig under construction along the Mobile River broke its moorings and floated 1.5 miles ( 2.4 km ) northwards before striking the Cochrane Bridge just outside Mobile . No significant damage resulted to the bridge and it was soon reopened . The damage on Dauphin Island was severe , with the surge destroying many houses and cutting a new canal through the western portion of the island . An offshore oil rig also became grounded on the island . As in Mississippi , the storm surge caused significant beach erosion along the Alabama coastline . More than 600,000 people lost power in Alabama as a result of Hurricane Katrina and two people died in a traffic accident in the state . Residents in some areas , such as Selma , were without power for several days . Bayou
Strait of Dover
The Rhine ( as the Urstrom ) flowed northwards into the North Sea as the sea level fell during the start of the first of the Pleistocene Ice Ages . The ice created a dam from Scandinavia to Scotland , and the Rhine , combined with the Thames and drainage from much of north Europe , created a vast lake behind the dam , which eventually spilled over the Weald into the English Channel . This overflow channel became the Strait of Dover about 425,000 years ago . A narrow deep channel along the middle of the strait was the bed of the Rhine in the last Ice Age . A geological deposit in East Anglia marks the old preglacial northward course of the Rhine .
Hurricane Harvey
Following its designation , the cyclone moved swiftly westward into the Caribbean Sea under the influence of an expansive ridge of high pressure to its north . An environment of moderate wind shear complicated the weather of the storm 's intensity , with global forecast models suggesting dissipation in the central Caribbean , whereas statistical and hurricane models suggested the potential for Harvey to be near hurricane strength in later days . Over the next day , the storm changed little in structure , remaining poorly organized with its low - level center on the eastern edge of associated deep convection . Harvey 's presentation began to deteriorate early on August 19 ; its convective pattern became elongated while the circulation became less defined . In fact , a reconnaissance aircraft was unable to find a loosely - closed circulation at 850 mb ( 4,781 ft ) , though it did locate one at lower levels . Harvey was downgraded to a tropical depression at 21 : 00 UTC on August 19 ; six hours later , based on continued data from a reconnaissance aircraft , it was declared an open tropical wave . The
Soil erosion
Rainfall , and the surface runoff which may result from rainfall , produces four main types of soil erosion : splash erosion , sheet erosion , rill erosion , and gully erosion . Splash erosion is generally seen as the first and least severe stage in the soil erosion process , which is followed by sheet erosion , then rill erosion and finally gully erosion ( the most severe of the four ) .
Tropical cyclone
Environmental steering is the dominant term . Conceptually , it represents the movement of the storm due to prevailing winds and other wider environmental conditions , similar to `` leaves carried along by a stream '' . Physically , the winds , or flow field , in the vicinity of a tropical cyclone may be treated as having two parts : the flow associated with the storm itself , and the large - scale background flow of the environment in which the storm takes place . In this way , tropical cyclone motion may be represented to first - order simply as advection of the storm by the local environmental flow . This environmental flow is termed the `` steering flow '' .
Soil erosion
Vegetation acts as an interface between the atmosphere and the soil . It increases the permeability of the soil to rainwater , thus decreasing runoff . It shelters the soil from winds , which results in decreased wind erosion , as well as advantageous changes in microclimate . The roots of the plants bind the soil together , and interweave with other roots , forming a more solid mass that is less susceptible to both water and wind erosion . The removal of vegetation increases the rate of surface erosion .
Strait of Dover
A 2007 study concluded the English Channel was formed by erosion caused by two major floods . The first was about 425,000 years ago , when an ice - dammed lake in the southern North Sea overflowed and broke the Weald - Artois chalk range in a catastrophic erosion and flood event . Afterwards , the Thames and Scheldt flowed through the gap into the English Channel , but the Meuse and Rhine still flowed northwards . In a second flood about 225,000 years ago the Meuse and Rhine were ice - dammed into a lake that broke catastrophically through a high weak barrier ( perhaps chalk , or an end - moraine left by the ice sheet ) . Both floods cut massive flood channels in the dry bed of the English Channel , somewhat like the Channeled Scablands or the Wabash River in the USA . A further update in 2017 , attributed a series of previously described underwater holes in the Channel floor - `` 100m deep '' and in places `` several kilometres in diameter '' to lake water plunging over a rock ridge causing isolated depressions or plunge pools . The melting ice and rising sea levels submerged Doggerland , the area linking Britain to France 6,500 -- 6,200 BCE .
Victoria Falls
The entire volume of the Zambezi River pours through the First Gorge 's 110 - metre - wide ( 360 ft ) exit for a distance of about 150 metres ( 500 ft ) , then enters a zigzagging series of gorges designated by the order in which the river reaches them . Water entering the Second Gorge makes a sharp right turn and has carved out a deep pool there called the Boiling Pot . Reached via a steep footpath from the Zambian side , it is about 150 metres ( 500 ft ) across . Its surface is smooth at low water , but at high water is marked by enormous , slow swirls and heavy boiling turbulence . Objects -- and humans -- that are swept over the falls , including the occasional hippopotamus or crocodile , are frequently found swirling about here or washed up at the north - east end of the Second Gorge . This is where the bodies of Mrs Moss and Mr Orchard , mutilated by crocodiles , were found in 1910 after two canoes were capsized by a hippo at Long Island above the falls . The principal gorges are ( see reference for note about these measurements ) :
Nile
The Bahr al Ghazal 's drainage basin is the largest of any of the Nile 's sub-basins , measuring 520,000 square kilometers ( 200,000 sq mi ) in size , but it contributes a relatively small amount of water , about 2 m / s ( 71 cu ft / s ) annually , due to tremendous volumes of water being lost in the Sudd wetlands .