Urban Design Principles For The Flood Resilience

Discuss about the Urban Design Principles For the Flood Resilience.

The Monsoons in Kerala

Kerala, at the southern tip of India, is a popular state among the international tourists and well known for its tropical hills, scenic green landscapes, and beaches. However, this year it was in the news for being battered by torrential floods and record monsoons. In India, floods are the most frequent and common of all natural disasters and the Kerala floods in recent time is the most striking example.
The annual precipitation, in India, is about 4,000 Billion Cubie Meter, and the seasonal monsoons account for 3,000 BCM out of the above (Mohapatra. & Singh 2003, pp. 131). Unequal seasonal distribution and temporal and spatial variations of the rainfall in India shows frequent departures from the normal. Different movement agencies have shown that the flood-prone area in India is increasing dramatically. According to the Central Water Commission (CEC), the annual average area due to floods is about 7.563 million ha. Between 1953 -2000, floods have impacted about 33 million persons (Mohapatra. & Singh 2003, pp. 131). With a steady rise in population, it is only apparent that the number of people affected due to floods is now much beyond the above-given numbers. The main reason behind floods in India in1ude riverbank erosion, inadequate capacity to contain high flows within riverbanks and silting of riverbeds.  Other factors include landslides, obstruction of flows and poor natural drainage in the flood-prone area as stated by Mohapatra. & Singh (2003 pp. 133).

Kerala has a unique geography and carries a vast expanse of low lying areas. About 10 percent lies below the sea level, and it is here where people have built their homes and businesses (Dutta, 2018). Kerala carries a high population density which is more than twice the national average. Severe floods affected the south Indian state that witnessed unusually high rainfall and the worst flooding during the monsoon season. Meteorologists reported Kerala received 37.5% more rainfall than average and Idukki in the north was the worst hit with 83.5% excess rain. More than eighty dams in the state had opened their gates to release their waters as their reservoir became dangerously high (Safi, 2018). The distressing floods in Kerala killed more than 300 (Safi, 2018). It is seen as the worst inundation crisis in a century for the country as the torrential rain and strong winds sent sweeping torrents flood waters through villages in the region.

Aerial photographs show little division between roads and backwaters of Kerala (Dutta, 2018). The floods have destroyed 45,000 hectares of farmland, 27,000 houses, and 134 bridges. 82,000 km of local roads and 16,000 km of Public Works Department roads have been completely destroyed (India today, 2018). Kulamavu, Adimali, and Cheruthoni are the worst damaged areas. The biggest challenge is to reach the affected areas and get the roads cleared. NH185 is a crucial link to the higher areas like Idukki and Munnar (Varma, Janardhanan & Philip, 2018).Flooding in the hilly terrain has led to the destruction of homes, road networks, bridges, and industries. The roads were damaged, and the international airport was closed, and more than 200,000 people were left homeless because of the unusually heavy rains (Safi, 2018). The floods forced people to leave their homes and live in relief camps. It will require a massive workforce and months to restore the damaged areas.

The Damage

The architecture of Kerala Architecture is of vernacular styles based on primitive circular, square or rectangular shapes. The houses are typically made of stones, timber, palm leaves and clay. Roofing is ridged and supported by wooden brackets and it is interesting to note that no nails are used and the roof frame is supported by pillars on walls (Faseehun, 2015). As one can infer that the way the houses are constructed in Kerala and the material used to construct them is not sturdy and offers no support or resilience in case of surging storms and heavy flooding.  This is the reason why the recent floods in Kerala have destroyed its vital infrastructure and brought life to a complete halt. Houses, roads and other buildings were completely flooded and destroyed. It is seen that most houses in Kerala are load-bearing structures and are made of bricks and laterite. There are no frames, and the house is covered with a large tiled roof and the tiles on the roof added to the problem as the tiles add to the weight, and the tiled pavements did not allow any absorption of water by the soil (Ramnani, 2018). The load-bearing structures made of bricks or laterite when subjected to water lose their strength significantly. The foundations of houses in Kerala are not strong as they are made of marine clay. Kochi airport is a good example of poor planning as it is built on paddy fields and wetlands. The airport extends up to the banks of the river. The airport is often flooded following monsoon rains in Kerala (Nagendra, 2018). The spread of high-rise buildings on hill slopes has weakened the soil. Thus, the unplanned development has made the region more susceptible and vulnerable to flash floods and landslides (Nagendra, 2018). Rebuilding homes and infrastructure would require a new urban architectural and planning vocabulary. Reinforced concrete structures should be built on stilts (Ramnani, 2018).
Why they got damaged due to floods in Kerala?
As the houses in Kerala rest on weak soil and foundation and are made of local natural building materials like timber, palm leaves and clay, they are not flood proof at all. What makes 2018 more devastating is because of the lower capacity of the state to deal with extreme floods. Illegal stone quarrying, mining on river beds and changing drainage patterns have raised the vulnerability and worsened the situation of the current floods (Tripathi, 2018). Environmentalists identify the use of land for high rises construction in the catchment areas of rivers and river-beds as the main reason behind the calamity (Dutta, 2018). The Western Ghats Ecology Expert Panel way back in 2011 had reported to the Indian Ministry of Environment and Forests about how the ill-focused development was destroying the sustainability of the Western Ghats hills (Nagendra, 2018). Activities such as quarrying, construction near protected forests and building dams were against the approach of thoughtful conservation.

Type of Building Structures that Got Damaged

Floods leave an immediate impact on the environment and the communities. The consequences and damage rely on the vulnerability of the natural and built environments. In Kerala, houses have been damaged entirely due to recent floods. The structures have collapsed in the heavy rain with the roofs giving in and water rushing inside. All possessions have been destroyed (Rajendran, 2018). The houses were partly or wholly submerged, and many electric poles and trees have been uprooted and fell on the ground or the houses. Most of the buildings and houses have been fully or partially damaged in the rains. Landslides have cut off the cities, towns, and villages from each other. The coastal areas and cities must develop flood tolerance and faster reorganization. Better evacuations and flood warning systems can lower the economic losses. Ecological wisdom is essential for those living-with-floods lifestyles (Liao, Le, & Nguyen 2016, pp. 70).  
What type of material should be used to avoid floods in Kerala?
Kerala needs to rethink on its strategies and use of materials for constructing buildings and homes. Government policymakers, the environmentalist and property developers must come together to build flood proof houses along the coastal areas of Kerala. Climate change is raising sea levels, and there are plenty of examples of coastal areas that are at risk of climate-driven flooding. The challenge lies in how to prepare people and lower the enormous impact on risk levels. Worldwide fatalities from coastal flooding are anticipated to cross $1 trillion annually by 2050 (Daigle & Singh 2018, pp. 25). Asia’s fast-growing coastal megacities like Mumbai, Dhaka, and Manila face severe threats in the future because of heavier rainfall, floods and storm surges. The environment and weather extremes can put a home under siege and stress anytime. However, one can build stronger homes that are flood and weatherproof with the use of advanced materials and clever architecture (Murphy 2017, pp.57). For example, a strong foundation can keep the homes safe from sinking into the ground. Vented design allows the floodwater to pass underneath the structure of the house.

Property developers in megacities should be aware of the sea level rise and the risks involved. Future-proof homes can be built by placing them on stilts and surrounding them with water-absorbing gardens (Daigle & Singh 2018, pp.29). Builders must learn from the past lessons and get better at resilient construction by using high-­performance materials as well as improved methods for construction. Modern methods and improved technologies can help build sturdier houses. Froe example, placing anchors at the foundation stage, using advanced weatherproof tapes and fluid-applied sealant for roofs and secure window and door protection can undoubtedly result in a better and stronger home (Cushman, 2017). It is essential to use water-tolerant materials when constructing the houses. A closer observation of the flood adapting strategies by the Vietnamese’s shows them living in stilt houses.  The earlier stilt houses had thatched roofs and bamboo or wooden floors and walls. Granite and concrete stilts are getting commoner today, and the roofs and walls are made of metal. Gaps in the floor ensure adequate ventilation within the house (Liao, Le, & Nguyen 2016, pp. 72). Those gaps also help to lower the force of the flood waves during stormy weather and allow natural drainage of water.

A house should protect its occupants, even against the weather extremes. Flooding, fire, and hurricanes often plague different parts of the world and damage dwellings and properties. The focus must be on how to reverse the environmental and ecological damage as well as on making stronger structures. There are essential lessons to be learned here.

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Dutta, P. K. (2018) Why Kerala floods killed so many, destroyed so much. India today [Online] available from: https://www.indiatoday.in/india/story/why-kerala-floods-killed-so-many-destroyed-so-much-1319998-2018-08-21 [Accessed 19 Sep 2018].
Daigle, K, & Singh, M. (2018) Coastal Catastrophe. Science News, 194(4), pp. 24-29.

Faseehun, M. (2015) Kerala architecture. slideshare [online] Available from:
https://www.slideshare.net/faseehun/kerala-architecture [Accessed 19 Sep 2018].
India today(2018) Kerala floods caused damage worth Rs 20,000 crore. Assocham India today [Online] Available from https://www.indiatoday.in/india/story/kerala-floods-damage-20000-crore-assocham-1318996-2018-08-20 [Accessed 19 Sep 2018].

Liao, K, Le, T, & Nguyen, K. (2016) Urban design principles for flood resilience: Learning from the ecological wisdom of living with floods in the Vietnamese Mekong Delta. Landscape And Urban Planning, 155(1), pp. 69-78.

Murphy, H. (2017) The everything-proof house. Popular Science, 289 (4), pp. 56-59.
Mohapatra, P.K. & Singh, R.D. (2003) Flood Management in India. Natural Hazards, 28(1), pp. 131-143.
Nagendra,H. (2018)  Kerala’s monsoon: lessons from recent floods in India. The conversation Available [Online] Available from https://theconversation.com/keralas-monsoon-lessons-from-recent-floods-in-india-101883 [Accessed 19 Sep 2018].

Rajendran, D. (2018) As Kerala Govt Plans New Houses, Victims Wish to Stay in Old Ones. The Quint [Online]. Available from https://www.thequint.com/news/india/kerala-floods-people-keep-damaged-houses-govt-plans-new-ones [Accessed 19 Sep 2018].
Ramnani, V. (2018) Kerala floods: Assess damage before moving back to your home. Money control [online] Available from:
https://www.moneycontrol.com/news/business/real-estate/kerala-floods-assess-damage-before-moving-back-to-your-home-2883111.html [Accessed 23 Sep 2018].
Safi, M.(2018) Kerala floods: death toll rises to at least 324 as rescue effort continues The Guardian [Online] Available from https://www.theguardian.com/world/2018/aug/17/kerala-floods-death-toll-rescue-effort-india [Accessed 19 Sep 2018].

Tripathi, B.(2018) Kerala flood less intense than deluge of 1924, so why was damage as great? Business Standard [Online] Available from https://www.business-standard.com/article/current-affairs/kerala-flood-less-intense-than-deluge-of-1924-so-why-was-damage-as-great-118082400420_1.html [Accessed 19 Sep 2018].

Varma, V, Janardhanan, A. & Philip, S. (2018) Rebuilding Kerala: Power cuts, damaged roads, destroyed houses and people fighting trauma The Indian Express [Online] Available from https://indianexpress.com/article/india/kerala-floods-rebuilding-power-cuts-damaged-roads-destroyed-houses-and-people-fighting-trauma-5324832/ [Accessed 19 Sep 2018].