Inundación

Definition

Flood is usually used as a general term to describe the overflow of water from a stream channel into normally dry land in the floodplain (riverine flooding), higher-than–normal levels along the coast and in lakes or reservoirs (coastal flooding) as well as ponding of water at or near the point where the rain fell (flash floods) (IRDR Glossary).

Facts and figures

Floods are the natural hazard with the highest frequency and the widest geographical distribution worldwide. According to the Organization for Economic Cooperation and Development (OECD)  flooding is one of the most common, widespread and destructive natural perils, affecting approximately 250 million people worldwide and causing more than $40 billion in damage and losses on an annual basis (OECD).

Flooding occurs most commonly from heavy rainfall when natural watercourses lack the capacity to convey excess water. It can also result from other phenomena, particularly in coastal areas, by a storm surge associated with a tropical cyclone, a tsunami or a high tide. Dam failure, triggered by an earthquake, for instance, will lead to flooding of the downstream area, even in dry weather conditions.

Various climatic and non-climatic processes can result in different types of floods: riverine floods, flash floods, urban floods, glacial lake outburst floods and coastal floods.

Flood magnitude depends on precipitation intensity, volume, timing and phase, from the antecedent conditions of rivers and the drainage basins (frozen or not or saturated soil moisture or unsaturated) and status. Climatological parameters that are likely to be affected by climate change are precipitation, windstorms, storm surges and sea-level rise (UNDRR).

When floodwaters recede, affected areas are often blanketed in silt and mud. The water and landscape can be contaminated with hazardous materials such as sharp debris, pesticides, fuel, and untreated sewage. Potentially dangerous mold blooms can quickly overwhelm water-soaked structures. Residents of flooded areas can be left without power and clean drinking water, leading to outbreaks of deadly waterborne diseases like typhoid, hepatitis A, and cholera (UNDRR).

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Related content on the Knowledge Portal

  • Monsoon rains triggered major flooding in northeastern India, submerging hundreds of villages and forcing thousands of people to abandon.

    Source: glidenumber

  • The north eastern and northern districts including Sylhet, Moulavibazar, Sunamganj, Habiganj, Netrokona, Kurigram, Gaibandha, Lalmonirhat of Bangladesh have been inundated due to heavy downpour and of on-rush flood water from upstream (Assam and Meghalaya in India) for last couple of weeks.

    Source: glidenumber

  • As of 22 June, according to government statistics, the latest round of floods which began early in the month of June has affected more than 29 million people and 1.6 million hectares of crops in the areas of Zhejiang, Fujian, Jiangxi, Hubei, Hunan, Guangdong, Guangxi, Chongqing, Sichuan and Guizhou. The downpours triggered flash floods, inundated crops, destroyed reservoirs and irrigation facilities, and disrupted traffic and telecommunications Latest figures indicate that up to 199 people have perished, 123 people are missing, 2.37 million people were evacuated, and 195,000 houses collapsed, with direct economic losses amounting to approximately CNY 42.1 billion (CHF 7.01 billion or EUR 5.03 billion).

    Source: glidenumber

  • Hundreds without shelter after floods caused by a tropical wave moving westward.

    Source: glidenumber

  • Torrents of flood water devastated towns and villages in northeastern Brazil, killing at least 38 people and leaving more than 600 missing and more than 50,000 without shelter.

    Source: glidenumber

  • Relief has been delivered to population affected by floods, heavy rains and landslides in the province of Panama.

    Source: glidenumber

  • At least 11 people were killed after heavy rains caused flooding around Ghana's capital, destroying homes and washing out roads, emergency officials in the West African country said on 21 June 2010.

    Source: glidenumber

  • For the past three days, the Northern Rakhine State (NRS) in Myanmar is facing continuous rains that have
    flooded several areas including in Maungdaw and Buthidaung. The Government has confirmed the death of 42 people (18 in Maungdaw and 24 in Buthidaung). Landslides have reportedly occurred in several places (in Buthidaung) and roads and bridges have either been cut or damaged by the floods in Maungdaw and Buthidaung. Several villages are severely flooded. Heavy rain in Myanmar has triggered floods and landslides, washing away bridges, blocking roads and killing at least 12 people, district officials said on Wednesday.

    Source: OCHA

    International Charter: Space and Major Disasters activated for Myanmar by UNITAR/UNISAT on behalf of UNDP.
    Link: http://www.disasterscharter.org/home...

    read more
  • Heavy rains caused floods and landslides in southeast Bangladesh, killing at least 58 people.

    Source: glidenumber

  • Up to 40,000 people evacuated after torrential rains caused heavy flooding in the southern Philippines.

    Source: glidenumber

     

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