Inland flooding. The City of Antwerp does not hold records of damage costs from inland flooding for the city. However, fluvial flooding from the Scheldt not only represents a risk to Antwerp’s real estate, infrastructure and heritage, but also increases the risk of toxic waste deposits left over by the spread of polluted sediment (Xxxxxxxx, 2008). According to the Green Plan of Antwerp, an estimated 63.9% of Antwerp’s surfaces (buildings and roads) are sealed, increasing the risk of river and pluvial flooding due to the reduced capacity to absorb excess water (VMM, 2009). This risk is predicted to increase with climate change (ProSes, 2013).
Inland flooding. Rainfall between December and February in the Basque country is expected to increase by between 5% and 20% as a consequence of climate change (Basque Government, 2008). In summer, rainfall is expected to decline by between 30% and 50%; however, the largest disruption is expected to be the seasonal distribution of rainfall rather than the percentage change itself (Basque Government, 2008). In the last 600 years, Bilbao has experienced 39 major flood events (Ibisate et al., 2000). Floods in Bilbao were traditionally due to the works of defence and channelling of the Xxx xx Xxxxxx which were completed late last century (Basas, 1983). In the first half of the twentieth century there were only two notable flooding events, the Nerbioi floods of December 1908 and May 1913. Floods then continued to affect Bilbao in October 1953, June 1975, June 1977 and August 1983 (see Table 8.3). These floods are thought to be due to the combination of rapid urbanisation and industrialisation of the city and the absence of maintenance work in the estuary.
Inland flooding. Floods are particularly common in the Tunjuelo River Basin (Southeast). The surrounding region includes 35 per cent of Bogota’s population (Pacific Disaster Center 2006). Overall, 18 per cent of the urban area of Bogota is occupied by people living in informal settlements, which amounts to about 1.4 million people. According to the Pacific Disaster Center (2006), a substantial number of informal settlements are in high risk zones of flooding and landslides which make them extremely vulnerable. The Tunjuelito River Flood in 2002 led to 2,109 people losing their homes in Bogota. Economic cost assessments have not been undertaken for the 2002 river flood. Yamin et al. (2013) have modelled flood risks in Bogota using a case study of the area surrounding the Quebrada Xxxxx River and estimated the maximum loss due to flooding for a period of up to 100 years (see Figure 8.6). They included losses due to number of people, buildings and direct economic losses of buildings, contents and profits (Yamin et al., 2013). The costs are estimated to increase every year and most significantly in the first 20 years.
Inland flooding. As the Musi river flows through Hyderabad the city has historically been susceptible to river flooding. However, since the creation of two large dams in the 1920s, the city is now less vulnerable to river flooding. With heavy rainfall occurring throughout the monsoon, and particularly high levels in September, Hyderabad is susceptible to pluvial flooding (Xxxxxx et al., 2010). This is especially the case with the effect of climate change increasing the frequency of extreme precipitation events. The maximum level of rainfall on record in a 24 hour period occurred on 24th August 2000, with 240.5mm of precipitation (Government of Andhra Pradesh, 2010). During this time, the water level in the Musi river did not increase considerably suggesting that the resulting floods were due to pluvial flooding rather than from the river (Geological Survey of India, 2013). The city faces various challenges that exacerbate flooding in Hyderabad. These include inadequate drainage capacity, illegal encroachment of natural water courses, diversion of water courses to allow for building, dumping of rubbish and building materials leading to silting of drains, and an increase of impervious surfaces leading to higher run off (GHMC, 2005). Case studies of previous floods include the severe floods on the 28th September 1908, 23rd-24th August 2000 and 8th-10th August 2008. Table 8.7 shows the damage costs and numbers of people affected from these floods, estimated by the India Meteorological Department (Xxxx, 2009) and the A.P. State Disaster Management Plan, August 2010. In the 2008 flood, the maximum intensity of rainfall was reported at 40mm per hour – substantially higher than Hyderabad’s drain capacity at around 12mm per hour (Xxxx, 2009). In the 2000 flood, 90 residential areas were flooded, in some cases under 3m to 4.5m of water, and parts of roads were washed away (Xxxxxx et al., 2013). 28/09/1908 23-24/08/2000 8-10/08/2008 Type of flooding Pluvial and river Pluvial Pluvial Rainfall 430mm 240.5mm 237mm Property Loss/Worth 80,000 houses 35,693 houses INR 1350m (EUR 32.7m) INR 495.2m (EUR 7.8m) Loss of life 15,000 26 0 Population Affected 600,000 200,000 150,000 Table 8.7: Severe flooding events in Hyderabad. Source: Xxxx, 2009 using data from the India Meteorology Department.
