The World Bank: Risk and Opportunity

Increasing Resilience towards Flooding in Mumbai city

CHINMAY CHAUHAN, Singapore

Managing Risks from Climate Changes

● Levels of risk in many global cities are likely to grow due to a combination of population growth, development and rising intensities of extreme weather events

● Managing risks from extreme events will be a crucial component of climate change adaptation.

● This resource aims at researching the causes and the exploring possible solutions to manage risk and increase resilience towards the yearly flooding caused during monsoons in Mumbai

● Brief contents of this presentation– About the city of Mumbai– Mumbai flooding of 2005 – Damage caused by 2005 Mumbai floods– Increasing resilience and managing risk in advance– Possible and plausible solutions

Mumbai – The biggest city in India

● Mumbai is the largest city in India with population in excess of 20 million● Island city: surrounded by Arabian Sea and other creeks on all sides

Mumbai

● Mumbai is the financial, commercial and entertainment capital of India.

● It is also one of the world's top ten centres of commerce in terms of global financial flow, generating 5% of India's GDP, and 70% of capital transactions to India's economy.

Monsoon Flooding in Mumbai

● Mumbai is prone to flooding and witnesses severe disruptions almost annually

● Flooding is an every year Phenomenon in Mumbai caused mainly due to poor drainage systems and rapidly increasing urban population, which puts pressure on the existing infrastructure

● For example, between 2004 and 2007, Mumbai experienced flooding each summer. But in July 2005, the city experienced the worst flooding in its recorded history.

● The city receives around annual rainfall of around 2400 mm. Storm water discharges to Arabian Sea/Thane Creek through road side drains, minor nallas (drains) and major nallas.

Public Transportation in Mumbai

● Local trains and BEST buses are the life line for the people of Mumbai

● They form the mode which majority of the middle class and lower class people use for day-to-day travel

● They are highly vulnerable to monsoon and a day of heavy rainfall can bring both the roads and railways in Mumbai to a standstill, which eventually paralyses the movement in the city

Local Trains

BEST public buses

Mumbai Floods of 2005

● The city receives average annual rainfall of around 2400 mm

● Storm water discharges to Arabian Sea/Thane Creek through road side drains. The Storm Water Drainage (SWD) system in Mumbai City is more than 100 years old

● Before urbanization and development 40% of urban storm water was flowing through open lands. Now after development 90% storm water is flowing through drains & 10% water is flowing through open lands.

● On July 26, 2005, the highest ever rainfall recorded in the last 100 years in the country battered suburban Mumbai and Mumbai city, which were the worst floods in history of Mumbai

● The continuous rainfall resulted in urban flash flooding

In Pictures – Mumbai Floods (July'05)

Damage caused by the 2005 Floods

● 447 casualties were reported in Mumbai

● 40,000 commercial establishments damaged.

● Vehicles Damaged - 30,000

● Heavy rains led to the closure of the airport

● Electricity supply was stopped in most parts of Mumbai’s Suburbs

● Submergence of railway tracks leading to stopping of railways

● Many landslides of small hills all over the city resulted in loss of lives and property.

Impact on the Marginalized poor population

● Mumbai has many slums on the banks of Mithi River (15km in length)

● Mithi river is supposed to lead the drainage water into the Arabian sea. But due to massive settlements and encroachments, most of the river area has been taken over for industrial or residential purposes

Impact on the Marginalized poor population

● Mithi river experiences regular flooding due to this, but the floods of 2005 had a catastrophic impact on the slums on the banks of the river.

● Estimated total household damage costs due to floods for the marginalized sections were around 235 million USD.

● Besides the damage there was also lost income due to the labour manhours lost due to total shutdown of the city

● Every year flooding causes great economic loss in addition to the loss of lives and livelihood, specially to the poor amongst affected population

● It’s of extreme importance to reduce and control the economic losses due to the floods i.e. becoming more resilient

Becoming Resilient and Effective Risk Management

Reducing direct losses from floods

● Reduce building vulnerability through building upgrades and renovation

● Widening existing waterway and river beds. Maintaining and freeing river beds. Ex: Mithi river bed can be widened by removing the encroached area settlements and also some of the industries alongside the river.

● Early warning systems and evacuation schemes can help prevent the loss of lives and help reduce property loss and damage.

● Improving drainage systems and existing transportation infrastructure, so that excess rains do not disrupt the public transport services

Becoming Resilient and Effective Risk Management

Reducing indirect losses from floods

● Indirect losses refer to the losses due to loss of man hours, disruption of economy, loss of industry production during re-construction period etc.

● Government can try to increase the construction sector production capacity, which eventually reduces the duration needed for re-construction of the damaged households and properties. This means that recovery is faster and thus the opportunities lost are lesser.

● Introduce easy insurance schemes backed by government for the poor sections of the society to reduce the risk they face from the natural disaster.

Policies to increase infrastructure resilience in Mumbai

Public transport

● Infrastructure development would befunded through a combination of taxation and public investment.

● Build the planned transport well above the sea-level as opposed to underground. Ex: Mumbai metro has been planned to be above the ground for most areas

Mumbai Metro

Building Codes

● Amend existing building regulations and introduce new regulations where necessary to ensure that in 20 years’ time all floodplain buildings are on stilts

● Unauthorized colonies/slums must be prevented.

Slums of Dharavi, biggest slum in Asia

Policies to reduce the flood hazard risks

Insurance

● Insurance should be a public investment since this is a govt. financed scheme

● A government scheme aimed at low-income households and the informal sector.

Disaster Management

● The formation and coordination of a ‘disaster management’ cell – including government, emergency services, logistics and weather-forecast services.

● It would also involve the building of designated safe shelters, as well as targeted communication and education to relevant sectors of the population

Emergency Response

● The definition of high-risk priority areas, the enforced movement of people living in those areas, the location and development of alternative settlements and the restoration of vacated areas.

Conclusion: Using Risk Management to Cope with Flood Hazard and Increase Resilience

● The Mumbai floods of 2005 prompted the government to take steps towards managing such extreme events in the future, however with little success.

● Government can use different policies as suggested in this report which broadly fit into the Knowledge, Protection, Insurance, Coping activities as discussed in the course

● Mumbai still suffered from floods in July, 2014, although the impact was severe, which can possibly be attributed to the government's efforts over the past 9 years.

● We conclude that managing flood-risk effectively in the scope of Mumbai can help reduce economic loss as well as the loss of lives and property. The benefits of steps we take today will be realized in the future.

References

● http://mdmu.maharashtra.gov.in/pdf/Flood/statusreport.pdf

● http://www.mca4climate.info/_assets/files/Mumbai_final.pdf

● http://icfr2013.ex.ac.uk/papers/E1_Sorensen.pdf

● http://en.wikipedia.org/wiki/Maharashtra_floods_of_2005

● http://www.corfufp7.eu/jahia/webdav/site/corfu/users/batijel8/public/ExeterMeeting15-16April2010/CaseStudies/05_Mumbai.pdf

● http://en.wikipedia.org/wiki/Mumbai

● http://www.rcuwm.org.ir/En/Events/Documents/Workshops/Articles/8/7.pdf