Management of flood events in cities and surrounding areas
Flooding in Porto Alegre of the Lagoa dos Patos in Brazil during May 2024
Urban flooding is the inundation of land or property in cities or other built environment, caused by rainfall overwhelming the capacity of drainage systems, such as storm sewers. Urban flooding can happen regardless of whether or not affected communities are located within designated floodplains or near any body of water.[1] It is triggered for example by an overflow of rivers and lakes, flash flooding or snowmelt. During the flood, stormwater or water released from damaged water mains may accumulate on property and in public rights-of-way. It can seep through building walls and floors, or backup into buildings through sewer pipes, cellars, toilets and sinks.
There are several types of urban flooding, each with a different cause. City planners distinguish pluvial flooding (flooding caused by heavy rain),fluvial flooding (caused by a nearby river overflowing its banks), or coastal flooding (often caused by storm surges). Urban flooding is a hazard to both the population and infrastructure. Some well known disaster events include the inundations of Nîmes (France) in 1998 and Vaison-la-Romaine (France) in 1992, the flooding of New Orleans (United States) in 2005, and the flooding in Rockhampton, Bundaberg, Brisbane during the 2010–2011 Queensland floods in Australia, the 2022 eastern Australia floods, and more recently the 2024 Rio Grande do Sul floods in Brazil.
In urban areas, flood effects can be made worse by existing paved streets and roads which increase the speed of flowing water. Impervious surfaces prevent rainfall from infiltrating into the ground, thereby causing a higher surface run-off that may by higher than the local drainage capacity.[2] The effects of climate change on the water cycle can also change the severity and frequency of urban flooding. This applies in particular to coastal cities which may be affected by sea level rise and higher rainfall intensity.[3]: 925
To reduce urban flooding, city planers can use for example the following approaches: building gray infrastructure, using green infrastructure, improving drainage systems, and understanding and altering land use. In general terms, integrated urban water management can help with reducing urban floods.
^"The Prevalence and Cost of Urban Flooding". Chicago, Illinois: Center for Neighborhood Technology. May 2013.
^Urban adaptation to climate change in Europe (Report). European Environment Agency. 2012. ISSN 1725-9177.
^Cite error: The named reference IPCC_WG2 was invoked but never defined (see the help page).
types of urbanflooding, each with a different cause. City planners distinguish pluvial flooding (flooding caused by heavy rain),fluvial flooding (caused...
intense floods and increased flood risk. The types of floods include areal flooding, riverine flooding, coastal flooding and urbanflooding. There is...
use remains limited. Flooding can occur in cities or towns as urbanflooding. It can also take place by the sea as coastal flooding. Sea level rise can...
drainage and flooding problems. IWM offers several techniques, including stormwater harvest (to reduce the amount of water that can cause flooding), infiltration...
sewers. Triggered by events such as flash flooding, storm surges, overbank flooding, or snow melts, urbanflooding is characterized by its repetitive, costly...
necessary purification. Urbanflood management has now become one of the highest priorities in urban development, Urbanflooding has a major impact on both...
runoff in urban areas is a primary cause of urbanflooding, which can result in property damage, damp and mold in basements, and street flooding. Surface...
out in this plan are: Sustainable Waste Management, Urban greening & biodiversity, Urbanflooding & water resource management, Energy & buildings, Air...
The history of flooding in Canada includes floods caused by snowmelt runoff or freshet flooding, storm-rainfall and "flash flooding", ice jams during ice...
the State Council as nationwide urban construction policy in 2014. The concept of sponge cities is that urbanflooding, water shortage, and heat island...
primary cause of the increasing trend in flooding frequency and severity in Pakistan. It has been the worst flooding since 1931 in Karachi, killing at least...
villages in peri-urban areas, that gravely disrupted the people’s lives. 2021 Islamabad flooding From June to August 2022, flooding affected most of Pakistan...
experience flooding during periods of high discharge. The soils usually consist of clays, silts, sands, and gravels deposited during floods. Because of...
2018). "Encroached drains, poor waste management put Karachi at risk of urbanflooding". DAWN.COM. Archived from the original on 8 July 2018. Retrieved 28...
nuisances from localized flooding and waste water. Rudimentary systems made from brick or stone channels constituted the extent of urban drainage technologies...
Coastal flooding occurs when dry and low-lying land is submerged (flooded) by seawater. The range of a coastal flooding is a result of the elevation of...
flooding of New Orleans (USA) in 2005, the flooding in Rockhampton, Bundaberg, Brisbane during the 2010–2011 summer in Queensland (Australia). Flood flows...
are inundated, basement and street flooding can occur. Unlike catastrophic flooding events, this type of urbanflooding occurs in built-up areas where human-made...
in Sindh, was struck by major flooding. Many people died in the city due to heavy rainfall resulting in urbanflooding. The Sindh government, under the...
Weather of 2021 2019 Pakistan floods and storms 2020 Karachi floods Climate of Islamabad "2 killed as urbanflooding hits parts of Islamabad following...
2013. "Rain forecast, flood warning for three days". The Nation. 24 July 2019. "UrbanFlooding Likely In Various Divisions: The Flood Forecasting Division...
of the most populous cities in the UAE, has experienced repetitive urbanflooding during the rainy season over the last three decades. Possible additional...
to flooding. Due to being part of such a basin and being less than 5 meters above mean sea level, Bangladesh faces the cumulative effects of floods due...
exacerbated inflation, causing food prices to rise. According to experts, urbanflooding in Guwahati in the near future is expected to worsen to the point where...
13,500 structures due to which urbanflooding occurs. India portal Weather portal 2020 Hyderabad floods Great Musi Flood of 1908 "NRSC map of low-lying...
2020-01-10. "The climate phenomenon linking floods and bushfires". 2019-12-07. Retrieved 2020-01-10. "Flooding in western Uganda kills more than a dozen"...
June 2005 Gujarat floods. The term 26 July, is used to refer to the day when the city of Mumbai came to a standstill due to flooding. Many people were...
Flash flooding is ongoing or expected to begin shortly. Rapid snowmelt is also occurring and will add to the flooding. This is a FLASH FLOOD EMERGENCY...
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