What is the fundamental definition of a flood?

A flood is defined as an overflow of water, or occasionally other fluids, that submerges land that is typically dry. The term can also refer to the inflow of the tide.

In what sectors are floods a significant concern?

Floods are of significant concern in agriculture, civil engineering, and public health.

How do human activities influence the frequency and intensity of floods?

Human changes to the environment, such as land use changes like deforestation and the removal of wetlands, as well as modifications to waterways or flood controls like levees, often increase the intensity and frequency of flooding.

What global environmental issues contribute to increased flooding?

Global environmental issues like climate change contribute to flooding by intensifying the water cycle, leading to more extreme weather events, and by causing sea level rise.

What are the main natural types of floods mentioned in the text?

The text identifies several natural types of floods: river flooding, groundwater flooding, coastal flooding, and urban flooding, which is sometimes referred to as flash flooding. Tidal flooding is also mentioned as potentially including elements of both river and coastal processes.

What is intentional flooding, and for what purposes is it used?

Intentional flooding involves the deliberate inundation of land that would otherwise remain dry. It is used for agricultural purposes, such as preparing paddy fields for rice cultivation, for military objectives to impede enemy movement, and for river management purposes, like diverting floodwaters.

How can a river channel contribute to flooding?

Flooding can occur in rivers when the rate of water flow exceeds the capacity of the river channel, particularly at bends or meanders in the waterway.

Why have people historically settled near rivers despite flood risks?

People have traditionally lived and worked by rivers because the land is often flat and fertile, and rivers provide easy travel and access to commerce and industry.

What are the short-term and long-term impacts of floods on public health?

In the short term, floods can increase the spread of waterborne and vector-borne diseases. In the long term, they can lead to the displacement of residents.

What is areal flooding, and what conditions cause it?

Areal flooding occurs in flat or low-lying areas when water supply from rainfall or snowmelt exceeds the rate at which it can infiltrate or run off. This excess water accumulates in place, sometimes to hazardous depths. It can be caused by saturated soil, frozen ground, or impermeable surfaces like concrete and pavement.

What causes muddy floods?

Muddy floods can occur when overland flow on tilled fields picks up sediments, carrying them as suspended matter or bed load.

What can obstruct river channels and cause localized flooding?

Localized flooding can be caused or worsened by drainage obstructions such as landslides, ice, debris, or beaver dams.

What types of rivers are most prone to slow-rising floods?

Slow-rising floods most commonly occur in large rivers with extensive catchment areas, often due to sustained rainfall, rapid snowmelt, monsoons, or tropical cyclones.

What is 'overland flooding' as experienced in the Red River Valley?

Overland flooding in the Red River Valley is a unique type of hybrid river/areal flooding where rapid spring snowmelt can push water out of tributary river banks, causing it to flow overland to other streambeds. This phenomenon is particularly devastating due to its unpredictability and speed in the flat terrain.

What types of rivers are more likely to experience flash floods?

Flash floods are more common in smaller rivers, rivers with steep valleys, rivers flowing over impermeable terrain, or in normally dry channels.

What can cause a sudden increase in river flow leading to flash floods?

Flash floods can be caused by localized convective precipitation (intense thunderstorms) or the sudden release of water from an upstream impoundment, such as behind a dam, landslide, or glacier.

How do flash floods behave in normally dry channels in arid zones?

In arid zones, flash floods in normally dry channels (arroyos) initially have their water depleted by wetting the sandy stream bed. As the flood progresses downstream, the rising limb of the hydrograph becomes quicker because the depletion effect becomes less significant relative to the total flow.

What factors contribute to coastal flooding?

Coastal areas can be flooded by storm surges, which are combined with high tides and large waves. In severe cases, tsunamis or tropical cyclones can also cause coastal flooding.

What is a storm surge?

A storm surge is defined as an additional rise of water generated by a storm, occurring above and beyond the predicted astronomical tides.

How does climate change affect coastal flooding?

Climate change contributes to intensified coastal flooding through sea level rise and an increase in the frequency and severity of extreme weather events. This, combined with coastal population growth, leads to greater impacts.

What causes flooding in estuaries?

Flooding in estuaries is typically caused by a combination of storm surges, driven by winds and low barometric pressure, and large waves interacting with high upstream river flows.

What is urban flooding?

Urban flooding is the inundation of land or property within cities or built environments, occurring when rainfall or coastal storm surges overwhelm the capacity of drainage systems like storm sewers. It can happen even if communities are not located near a body of water.

What are the different types of urban flooding based on their cause?

City planners distinguish between pluvial flooding (caused by heavy rain), fluvial flooding (caused by a nearby river overflowing), and coastal flooding (often caused by storm surges).

What are some notable examples of urban flooding disasters?

Notable urban flooding disasters include events in Nîmes and Vaison-la-Romaine (France), New Orleans (United States), Rockhampton, Bundaberg, and Brisbane (Australia), and Porto Alegre (Brazil).

What are the purposes of intentional floods?

Intentional floods are carried out for agricultural purposes (like preparing paddy fields), military objectives (to create obstacles), and river management (to divert floodwaters).

What characterizes a 'controlled' military inundation?

A controlled military inundation takes civilian interests into account by allowing timely evacuation, being reversible, and attempting to minimize adverse ecological impacts.

What are the primary causes of floods listed in the article?

Floods are caused by factors such as prolonged heavy rainfall, accelerated snowmelt, severe winds over water, unusual high tides, tsunamis, or the failure of water-retaining structures like dams and levees. Wildfires can also exacerbate flooding by reducing vegetation cover.

How do human activities like draining wetlands contribute to flooding?

Draining wetlands, which naturally store large amounts of water, and increasing paved surfaces that do not absorb water, contribute to flooding by increasing the volume of surface runoff that exceeds the capacity of stream channels and reservoirs.

What are the key 'upslope factors' that determine flood magnitude?

The most important upslope factor is the land area of the watershed upstream. For smaller watersheds, rainfall intensity is the second most important factor, while for larger watersheds, the main channel slope is the second most important factor.

What is the 'Time of Concentration' in flood prediction?

The Time of Concentration is the time it takes for runoff from the most distant point of a drainage area to reach a specific point in the channel. This time helps define the critical duration of peak rainfall for that area.

What 'downslope factors' can limit water movement and affect flood levels?

Downslope factors include the ocean or coastal bars in coastal flooding, tidal fluctuations, tsunamis, storm surges, and restrictions in the flow channel such as bridges, canyons, vegetation growth, or accumulated ice and debris.

How can climate change specifically impact rainfall and flooding patterns?

Climate change can lead to increased heavy rainfall events, potentially making floods more severe. However, in some regions, drier soils due to climate change might absorb rainfall more quickly, leading to less flooding, though dry, hardened soils can also increase runoff and flood risk.

What are 'coincident events' that can lead to extreme floods?

Coincident events that can cause extensive flooding include the combination of intense rainfall with snowmelt, leading to ice jams, and the accumulation of debris or debris from damaged structures and vehicles within flood channels.

What is the destructive power of floodwaters?

Floodwaters possess significant destructive power, capable of demolishing buildings, bridges, structures, trees, and vehicles. The economic, social, and environmental damages caused by floods can be catastrophic.

What are the primary economic impacts of flooding?

The primary economic impacts include loss of life, damage to buildings and infrastructure like sewerage systems and roadways, and substantial financial losses, often amounting to billions of dollars annually for countries like the United States.

How can floods affect agriculture and food security?

Floods can inundate farmland, making it unworkable and preventing crop planting or harvesting, potentially leading to food shortages for both humans and livestock, and in extreme cases, the loss of entire national harvests.

What are the health consequences of floods, beyond direct fatalities?

Beyond drowning, floods can lead to deaths from dehydration, heat stroke, heart attacks, and illnesses due to the inability to deliver medical supplies. Injuries can occur during and after floods from debris, fast-moving water, and rescue attempts. Communicable diseases like cholera and hepatitis can spread due to contaminated water and poor sanitation.

How do floods impact housing and lead to long-term health issues?

Floods can cause chronically wet houses, promoting the growth of indoor mold, which is linked to respiratory symptoms, allergic rhinitis, and asthma. Residual standing water after floods also increases the risk of vector-borne diseases.

What are the psychosocial impacts of floods on victims?

Flood victims can suffer significant psychosocial impacts, including depression and stress resulting from losses such as deaths, injuries, and property destruction.

What are the deadliest types of flood-related fatalities?

Fatalities directly connected to floods are most commonly caused by drowning due to deep water and strong currents. However, deaths can also result from dehydration, heat stroke, heart attacks, and illnesses where medical supplies cannot be delivered.

What are some of the deadliest floods in history, based on the provided table?

Historically devastating floods include the 1931 China floods (estimated 2.5-3.7 million deaths), the 1887 Yellow River flood (900,000-2 million deaths), the 1938 Yellow River flood (500,000-700,000 deaths), and the Banqiao Dam failure in China in 1975 (231,000 deaths).

What are the positive impacts or benefits of floods?

Floods, especially smaller or more frequent ones, can recharge groundwater, increase soil fertility and nutrients, provide essential water resources in arid regions, kill pests, and maintain river corridor ecosystems and floodplain biodiversity.

How do floods benefit ecosystems and fisheries?

Freshwater floods play a crucial role in maintaining river corridor ecosystems and floodplain biodiversity. They can spread nutrients to lakes and rivers, leading to increased biomass and improved fisheries for several years, and inundated floodplains can provide suitable spawning grounds for fish.

What flood management methods are considered 'structural'?

Structural flood management methods, also known as flood control, involve physically holding back floodwaters. Examples include building flood walls, detention basins, levees, bunds, reservoirs, and weirs.

What are examples of 'non-structural' flood management approaches?

Non-structural flood management methods focus on reducing risk and vulnerability without physically holding back water. This includes strategies like land use planning, flood risk assessment, nature-based solutions such as restoring marshes and floodplains, and implementing sustainable urban drainage systems (SUDS).

What is the role of 'soft infrastructure' in flood management?

In landscape engineering, it is considered best practice to rely more on soft infrastructure and natural systems, such as marshes and floodplains, for handling increased water volumes, as opposed to solely relying on hard infrastructure.

What are some examples of coastal flood defenses?

Coastal flooding has been addressed in various regions with defenses such as sea walls, beach nourishment, and barrier islands.

What measures can be taken in urban areas to manage flooding?

In urban areas prone to flooding, solutions include repairing and expanding sewer systems, reducing impervious surfaces through green infrastructure like porous paving and wetlands, converting flood-prone areas into parks, elevating buildings, and installing floodwalls or levees.

What is the National Weather Service's advice regarding driving through floodwaters?

The National Weather Service advises people to 'Turn Around, Don't Drown,' recommending that they leave flood areas rather than attempting to drive through them.

What are the key components of flood safety planning?

Flood safety planning involves observing past floods, using hydrologic and hydraulic models, mapping future flood scenarios, long-term land use planning, engineering flood control structures, intermediate-term forecasting and emergency response planning, and short-term monitoring, warning, and response operations.

What hazards do clean-up workers face after floods?

Clean-up workers face hazards such as electrical dangers, carbon monoxide exposure, musculoskeletal injuries, heat or cold stress, motor vehicle accidents, fire, drowning, and exposure to hazardous materials, biological hazards, and unstable debris.

Flood Wiki: Navigating the Deluge: A Comprehensive Flood Guide

Dive in with Flashcard Learning!

When you are ready...
🎮 Play the Wiki2Web Clarity Challenge Game🎮

Defining the Flood

Overflowing Waters

A flood is characterized as an overflow of water, or occasionally other fluids, that submerges land typically remaining dry.^[1] The term can also refer to the inflow of the tide. Floods represent a significant concern across various disciplines, including agriculture, civil engineering, and public health.^[1]

Human Influence and Climate

Human alterations to the environment frequently exacerbate the intensity and frequency of flooding. Practices such as deforestation, wetland removal, modifications to waterway courses, and the implementation of flood controls like levees can significantly influence flood dynamics.^[2] Furthermore, global environmental shifts, notably climate change, contribute to an intensification of the water cycle and sea level rise, leading to more frequent and severe extreme weather events and consequently, increased flood risks.^[2]

Global Significance

Floods are a critical global issue, impacting vast populations and economies. The proximity of a large portion of the world's population to coastlines and the location of major cities and agricultural regions near floodplains highlight the inherent vulnerability.^[8]^[9] The escalating risk of coastal and fluvial flooding due to changing climatic conditions underscores the need for comprehensive understanding and management.^[10]

Classifying Floods

Areal Flooding

Areal flooding occurs in flat or low-lying areas when precipitation, typically from rainfall or snowmelt, exceeds the capacity of the land to infiltrate or drain.^[11] This excess water accumulates, sometimes to hazardous depths, particularly when the ground is saturated, frozen, or covered by impermeable surfaces.

River Flooding

River flooding happens when the discharge rate of a river surpasses the capacity of its channel, often occurring at bends or meanders.^[6] These events can range from slow-rising floods in large river systems to rapid flash floods in smaller, steeper valleys or normally dry channels, often triggered by intense localized rainfall or sudden releases from upstream impoundments.

Coastal Flooding

Coastal areas are susceptible to flooding from storm surges, high tides, and large ocean waves that overtop defenses or, in severe cases, from tsunamis or tropical cyclones.^[14] Climate change, contributing to sea level rise and more extreme weather, is intensifying these events and increasing population exposure.^[15]

Urban Flooding

Urban flooding involves the inundation of land or property within cities and built environments. It is caused by rainfall or coastal storm surges overwhelming drainage systems like storm sewers.^[16] This can occur irrespective of proximity to natural floodplains, often resulting from rapid runoff on impervious surfaces.

Intentional Floods

Certain floods are intentionally created for specific purposes, such as agricultural preparation (e.g., paddy fields), military objectives to impede enemy movement, or river management strategies to divert floodwaters from critical areas.^[17] These can be controlled, considering civilian and ecological impacts, or uncontrolled, as seen in historical military inundations.

Drivers of Flooding

Natural Phenomena

Floods are primarily driven by natural meteorological and hydrological processes. These include prolonged heavy rainfall, often concentrated over a catchment area, rapid snowmelt, severe winds generating storm surges over bodies of water, and seismic events causing tsunamis.^[2]

Human Environmental Impact

Human activities significantly amplify flood risks. The conversion of wetlands, which naturally store water, and the proliferation of impervious surfaces in urban areas reduce the land's capacity to absorb rainfall, leading to increased surface runoff that overwhelms natural and engineered drainage systems.^[24]

Climate Change Amplification

Climate change is a critical factor, leading to an intensification of the global water cycle. This results in more frequent and severe extreme weather events, including heavier rainfall and accelerated snowmelt, directly contributing to increased flood severity and frequency.^[2]^[5]

Coincidental Factors

The most devastating flood events often arise from a confluence of factors. This can include the simultaneous occurrence of intense, warm rainfall with heavy snowpack melt, leading to ice jams and the release of impoundments, or the interaction of multiple extreme weather systems.^[33] Such coincidences can result in flood magnitudes exceeding those predicted by simpler models.

Consequences of Flooding

Infrastructure and Societal Damage

Floods possess immense destructive potential, capable of demolishing buildings, bridges, and infrastructure. They can cause widespread displacement of populations and lead to catastrophic economic and environmental damage, with incidents worldwide resulting in devastating impacts on human life and societal stability.^[37]

Economic Repercussions

The economic toll of floods is substantial, often amounting to billions of dollars annually. This includes direct damage to property, loss of livelihoods through agricultural devastation, business closures (nearly 40% of small businesses fail after a disaster), reduced property values due to water damage, and increased costs for rebuilding and recovery.^[9]^[39]

Health Hazards

Flooding poses significant health risks, primarily through drowning and injuries from debris. Post-flood, communicable diseases like cholera, hepatitis A and E, and gastrointestinal illnesses surge due to contaminated water supplies and poor sanitation.^[44] Respiratory issues from mold growth in damp conditions and mental health impacts like depression are also prevalent.^[47]

Beneficial Ecological Effects

While often destructive, floods, particularly smaller, periodic ones, offer ecological benefits. They replenish groundwater, enhance soil fertility by depositing nutrient-rich sediments, and support biodiversity in riparian zones.^[49] Floodplains can serve as crucial spawning grounds for fish and provide increased food sources for bird populations.

Mitigation and Resilience

Flood Management Strategies

Flood management encompasses structural measures (e.g., levees, dams, weirs) and non-structural approaches (e.g., land-use planning, nature-based solutions).^[52] The emphasis is shifting towards integrating natural systems like marshes and floodplains for enhanced resilience, especially in the context of climate change adaptation.^[53]

Safety Planning and Design

Effective flood safety planning involves meticulous analysis, including historical data assessment, hydrological and hydraulic modeling, and mapping future flood scenarios.^[56] Critical infrastructure should be located in low-risk zones, while flood-prone areas can be designated for temporary uses or protected by elevated structures and floodwalls.

Clean-up Safety Protocols

Post-flood clean-up operations present numerous hazards, including electrical risks, carbon monoxide exposure, musculoskeletal strain, and contact with hazardous materials and biological contaminants.^[60] Proper personal protective equipment (PPE) and adherence to safety protocols are essential for workers and volunteers.

Forecasting and Prediction

Statistical and Physical Modeling

Flood prediction relies on statistical analysis of historical flow data to estimate recurrence intervals (e.g., the 100-year flood). Physical process models, such as HEC-RAS, simulate water flow and inundation across channels and floodplains, integrating real-time data and quantitative precipitation forecasts for improved accuracy.^[61]

Global Monitoring Systems

Tools like the Global Flood Monitoring System (GFMS) utilize satellite data (e.g., from NASA's GPM) combined with land surface models to map flood conditions worldwide. These systems provide real-time and forecasted data on rainfall, streamflow, and water depth, enabling proactive measures.^[67]

Early Warning Systems

Anticipating floods through accurate forecasting allows for timely warnings, enabling communities to take precautions, evacuate vulnerable areas, and mobilize emergency resources effectively. The National Weather Service's Flash Flood Guidance provides crucial information for urban flood preparedness.^[71]

Assessing Flood Risk

Defining Flood Risk

Flood risk is defined by the interplay of specific hazards (e.g., flood intensity, duration) and the vulnerability and exposure of populations and assets. Understanding these elements is crucial for selecting appropriate mitigation strategies.^[72]

Population Exposure

A significant global population resides in coastal zones and floodplains, areas inherently susceptible to inundation. This widespread exposure, coupled with the increasing likelihood of severe flooding due to climate change, elevates the overall flood risk profile.^[8]^[9]^[10]

Floods in Society and Culture

Myths and Religious Narratives

Flood narratives are prevalent across global cultures and religions, often depicting great floods sent by deities as acts of divine retribution or cleansing, followed by rebirth.^[73] These myths, found in Sumerian, biblical, and various indigenous traditions, frequently feature a culture hero who survives to repopulate the world.

Etymological Roots

The word "flood" originates from the Old English term flōd, sharing roots with other Germanic languages and Latin words related to flowing water.^[74] It historically denotes an overflowing of water, a deluge, or a mass of water.

Historical Impact: Deadliest Floods

Catastrophic Events

Throughout history, floods have caused immense loss of life and devastation. The following table highlights some of the most catastrophic flood events globally, based on estimated death tolls.

Death Toll	Event	Location	Year
2,500,000–3,700,000^[48]	1931 China floods	China	1931
900,000–2,000,000	1887 Yellow River flood	China	1887
500,000–700,000	1938 Yellow River flood	China	1938
231,000	Banqiao Dam failure, Typhoon Nina	China	1975
230,000	2004 Indian Ocean tsunami	Indonesia	2004
145,000	1935 Yangtze river flood	China	1935
100,000+	St. Felix's flood, storm surge	Netherlands	1530
100,000	Hanoi and Red River Delta flood	North Vietnam	1971
100,000	1911 Yangtze river flood	China	1911

Teacher's Corner

Edit and Print this course in the Wiki2Web Teacher Studio

Edit and Print Materials from this study in the wiki2web studio

Click here to open the "Flood" Wiki2Web Studio curriculum kit

Use the free Wiki2web Studio to generate printable flashcards, worksheets, exams, and export your materials as a web page or an interactive game.

True or False?

Test Your Knowledge!

Gamer's Corner

Are you ready for the Wiki2Web Clarity Challenge?

Learn about flood while playing the wiki2web Clarity Challenge game.

Unlock the mystery image and prove your knowledge by earning trophies. This simple game is addictively fun and is a great way to learn!

Play now

Explore More Topics

Discover other topics to study!

list of beaches in new england

temples of cybele in rome

motor australian magazine

2022 rolex paris masters– singles

david marrero

title 47 of the code of federal regulations

attack on pearl harbor

data deficient

muscular christianity

givat ram

References

"Red River of the North State Water Trail". Minnesota DNR. Accessed 8 September 2024

"Flood Control", MSN Encarta, 2008 (see below: Further reading).

Babbitt, Harold E. & Doland, James J., Water Supply Engineering, McGraw-Hill Book Company, 1949

Center for Neighborhood Technology, Chicago IL "The Prevalence and Cost of Urban Flooding", May 2013

"Protecting Your Businesses", last updated March 2013

Dyhouse, G., "Flood modelling Using HEC-RAS (First Edition)", Haestad Press, Waterbury (USA) 2003-26-41

A full list of references for this article are available at the Flood Wikipedia page

Feedback & Support

To report an issue with this page, or to find out ways to support the mission, please click here.

Disclaimer

Important Notice

This page was generated by an Artificial Intelligence and is intended for informational and educational purposes only. The content is based on a snapshot of publicly available data from Wikipedia and may not be entirely accurate, complete, or up-to-date.

This is not professional advice. The information provided on this website is not a substitute for professional hydrological, engineering, or disaster management consultation. Always refer to official meteorological and governmental advisories for current conditions and safety recommendations. Never disregard professional advice or delay in seeking it because of something you have read on this website.

The creators of this page are not responsible for any errors or omissions, or for any actions taken based on the information provided herein.

Navigating the Deluge

💡 Dive in with Flashcard Learning! 💡

Defining the Flood 🌊

💧 Overflowing Waters

📈 Human Influence and Climate

🌍 Global Significance

Classifying Floods 🗂️

☁️ Areal Flooding

🏞️ River Flooding

🏖️ Coastal Flooding

🏙️ Urban Flooding

⚙️ Intentional Floods

Drivers of Flooding ⚙️

🌧️ Natural Phenomena

🌳 Human Environmental Impact

🌡️ Climate Change Amplification

🤝 Coincidental Factors

Consequences of Flooding ⚠️

🏚️ Infrastructure and Societal Damage

💰 Economic Repercussions

🤒 Health Hazards

🌱 Beneficial Ecological Effects

Mitigation and Resilience 🛡️

🏗️ Flood Management Strategies

🗺️ Safety Planning and Design

🧰 Clean-up Safety Protocols

Forecasting and Prediction 🔮

📊 Statistical and Physical Modeling

🛰️ Global Monitoring Systems

🚨 Early Warning Systems

Assessing Flood Risk 🧐

⚖️ Defining Flood Risk

📍 Population Exposure

Floods in Society and Culture 🏛️

📜 Myths and Religious Narratives

🗣️ Etymological Roots

Historical Impact: Deadliest Floods 💀

📈 Catastrophic Events

Teacher's Corner 🧑‍🏫

Edit and Print this course in the Wiki2Web Teacher Studio

True or False? 🤔

❓ Test Your Knowledge! ❓

Gamer's Corner 🎮

Are you ready for the Wiki2Web Clarity Challenge?

Explore More Topics

📜 Discover other topics to study!

References

📜 References

Feedback & Support 👍

To report an issue with this page, or to find out ways to support the mission, please click here.

Disclaimer ⚠️

📜 Important Notice

Dive in with Flashcard Learning!

Defining the Flood

Overflowing Waters

Human Influence and Climate

Global Significance

Classifying Floods

Areal Flooding

River Flooding

Coastal Flooding

Urban Flooding

Intentional Floods

Drivers of Flooding

Natural Phenomena

Human Environmental Impact

Climate Change Amplification

Coincidental Factors

Consequences of Flooding

Infrastructure and Societal Damage

Economic Repercussions

Health Hazards

Beneficial Ecological Effects

Mitigation and Resilience

Flood Management Strategies

Safety Planning and Design

Clean-up Safety Protocols

Forecasting and Prediction

Statistical and Physical Modeling

Global Monitoring Systems

Early Warning Systems

Assessing Flood Risk

Defining Flood Risk

Population Exposure

Floods in Society and Culture

Myths and Religious Narratives

Etymological Roots

Historical Impact: Deadliest Floods

Catastrophic Events

Teacher's Corner

True or False?

Test Your Knowledge!

Gamer's Corner

Discover other topics to study!

References

Feedback & Support

Disclaimer

Important Notice