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).

UN-SPIDER Regional Support Offices with hazard-specific expertise

Related content on the Knowledge Portal

  • At least 63 people have been killed from flooding and landslides in northern India. Authorities have evacuated about 5,000 people to safety from Uttarakhand state.

    Source: GLIDEnumber

  • Floods have displaced nearly 60,000 people in the last month in south Sudan with many at risk of malaria and other diseases.The assessment committee's report states that some 250 families covering 2470 people were affected by the flash floods. It is also reports that 176 families in Panthou have been displaced during the 24 hour torrential downpour that hit part of greater Aweil South County.

    Sources: www.alertnet.org, www.reliefweb.int

     


    Status Update: 15/09/2010


    Contacts:

    UNOOSA/UN-SPIDER

    Email: un-spider [at] ...

    read more
  • On 5 and 6 September 2010 torrential rain recorded 202.6mm which is 20% of total rainfall normally received by the country. The rainfall caused floods almost nationwide affecting over 25,000 people by destroying their residences, and other basic livelihoods. On 7 September 2010, the Government of the Gambia declared a State of National Disaster due to the magnitude and complexity of the floods.

    Source: www.glidenumber.net

  • Torrential rain from 19 to 21 August 2010 led to the flooding of 8 regions affecting 38 communities. The collapse of houses has led to the displacement of over 1,000 families.

    Source: GLIDEnumber

  • Torrential rain since Thursday, September, 2nd 2010 lead to floods in the main part of Senegal and many towns. The most affected, Dakar, the capital gathers in his suburbs (Pikine and Guediewaye Departements) more than 30,000 affected households. Departement of Velingara in the South of Senegal gathers 1,042 affected people with 105.5 ha of flooded farms.
    Source: OCHA- ROWCA

    -----------------------------------------------------------------------------------------------------------------------------

    Status Update: 13/09/2010

    -----------------------------------------------------------------------------------------------------------------------------

    Contacts:

    UNOOSA/UN-SPIDER

    ...

    read more
  • - 44 people have been reported dead, and some 50,364 people have been affected by recent torrential rains.

    - The National Coordinator for Disaster Risk Reduction has declared a national level orange alert while the State of National Calamity continues.

    - The UN System and the Humanitarian Network have finalized the flash appeal review process In order to continue to support most vulnerable populations.

    - UN agencies are currently monitoring the situation on the ground in order to respond and to evaluate the needs of the affected population.

    - Food distribution continues in shelters and affected areas around de country.

     

    Source: ReliefWeb
     

    DEADLY landslides in Guatemala are the culmination of one of the worst rainy seasons in half a century, aid workers at Plan International report.

    In June, 80,000 people were left homeless...

    read more
  • Floods have affected more than 340 families countrywide following torrential rains.

    Source: Glidenumber

  • Around 2000 are affected by the massive floods in Bendang Man, Sik Kedah. Malaysia Red Cross started emergency operation to deliver humanitarian aid.

    Source: glidenumber

    The month of Ramadan never stop the Malaysian Red Crescent volunteers to help those in needs. Their highly commitment and dedication bring them to Kedah to help around 2000 floods victims affected by the massive floods in Bendang Man, Sik Kedah. The convoy left for Kedah yesterday and led by Jasni Hashim, MRC Director of Operations with the emergency supplies to children and families affected. The supplies comprises of drinking water, clothes and personal hygiene kit.

    Source: Malaysian Red Crescent

  • Intermittent moderate to heavy rains that prevailed from July 26-30, 2010 trigerred the overflowing of Simuay River and other tributaries which caused flooding in the municipalities of Sultan Kudarat, Pagalungan and Datu Montawal, all in Maguindanao; Lambayong, Sultan Kudarat Province; and Kabacan, North Cotabato, thus, affecting 16,184 families in 35 barangays in Region XII.

    Source: glidenumber

    For more summary of flooding in Region XII please see also official NDCC update.

     

    read more
  • On 6 August 2010, at least 80 people were killed and more than 200 injured when heavy rains triggered flash floods and landslides in the frontier town of Leh, police said.

    Source: glidenumber

    SRINAGAR, India, Aug 7 (Reuters) - Heavy rainfall was hampering rescue and relief efforts in India's Himalayan region of Ladakh on Saturday, the army said, after flash floods killed at least 113 people.

    Scores of people were missing, and some foreign tourists were also believed to have been affected, the foreign ministry said.

    The airport in Leh town, dotted with Buddhist monasteries, was open and planes carrying disaster response teams, doctors and communications equipment have been dispatched.

    Source: ReliefWeb

Term Parents

UN-SPIDER Regional Support Offices with hazard-specific expertise