The Maharashtra Floods are referred to as the floods that occurred in various parts of Maharashtra, India. This included most of the area of metropolis city Mumbai located on the west coast of India beside the Arabian Sea. Because of these floods on an average 1100 people were found dead and many were left homeless. This disaster came just after a month of Gujarat Floods of June 2005. This day is remembered by many as the standstill day for all Mumbaikars (people of Mumbai).
A large number of people were standing on roads, lost their homes, while many walked long distances back home from work that evening. The floods were caused by the eighth heaviest-ever recorded 24-hour rainfall figure of 944 mm (37.17 inches) which lashed the metropolis on 26 July 2005, and intermittently continued for the next day. 644mm (25.35 inches) was received within the 12-hour period between 8 am and 8 pm. Torrential rainfall continued for the next week.
The highest 24-hour period in India was 1,168 mm (46.0 inches) in Aminidivi in the Union Territory of Lakshadweepon 6 May 2004 although some reports suggest that it was a new Indian record. The previous record high rainfall in a 24-hour period for Mumbai was 575 mm. Other places severely affected were Raigad, Chiplun, Khed Ratna 31 July after heavy rains disrupted the city once again, grounding all flights for the day.
On 26 July 2005, around 2:00 pm, the Mumbai Metropolitan Region was struck by a severe storm and subsequent deluge. The Indian Meteorological Department (IMD) station in Santacruz recorded 944 mm. of rain for the 24 hours ending at 8:30 a.m. on 27 July. The Municipal Corporation of Greater Mumbai [MCGM] control room started receiving phone calls reporting the heavy rain and subsequent water logging in suburban areas.
Local train movement came to a halt by 2:30 p.m. due to the water-logging on the tracks. This caused traffic on roads to increase dramatically with water logging and submerging of certain low-lying pockets of the region, such as Dharavi and Bandra-Kurla Complex.
Thousands of school children were stranded due to flooding and could not reach home for up to 24 hours. The following two days were declared as school and college holidays by the state government.
The rain water caused the sewage system to overflow and all water lines were contaminated. The Government ordered all housing societies to add chlorine to their water tanks while they decontaminated the water supply.
Development in certain parts of Mumbai is haphazard and buildings are constructed without proper planning. The drainage plans in northern suburbs is chalked out as and when required in a particular area and not from an overall point of view.
The Environment Ministry of the Government of India was informed in the early 1990s that sanctioning the Bandra-Kurla complex (a commercial complex in northern Mumbai) was leading to disaster. No environment clearance is mandatory for large urban construction projects in northern Mumbai. Officials in the environment ministry claimed that it was not practical to impose new guidelines with retrospective effect “as there are millions of buildings”.
For the first time ever, Mumbai’s airports ( Chatrapati Shivaji International Airport and Juhu aerodrome) were shut for more than 30 hours due to heavy flooding of the runways, submerged Instrument Landing System equipment and extremely poor visibility. Over 700 flights were cancelled or delayed. The airports reopened on the morning of 28 July 2005. Within 24 hours of the airports becoming operational, there were 185 departures and 184 arrivals, including international flights. Again from early morning of 31 July, with increase in water logging of the runways and different parts of Mumbai, most of the flights were indefinitely cancelled.
Rail links were disrupted, and reports on late evening of 30 July indicated cancellation of several long distance trains till 6 August 2005. The Mumbai-Pune Expressway, which witnessed a number of landslides, was closed the first time ever in its history, for 24 hours. According to the Hindustan Times, an unprecedented 5 million mobile and 2.3 million MTNL landline users were hit for over four hours. According to the .in registrar (personal communication), the .in DNS servers in Mumbai had to be reconfigured because the servers were not operational.
The floods have been the subject of research by scientists and social scientists attempting to understand the causes, impacts, and short/long term consequences. Scholars have studied the floods in Mumbai from the perspectives of climate change, disaster management / mitigation, urban health, vulnerability and adaptation, hydrology, environmental degradation and encroachment etc. Kapil Gupta (2007) assesses urban flood resilience, while Andharia (2006) contrasts the “widespread acts of generosity and altruism” in Mumbai with the general social disorder that was seen in the aftermath of Hurricane Katrina in New Orleans. Aromar Revi (2005) draws lessons from the floods for prioritising multi-hazard risk mitigation. Parthasarathy (2009) links social and environmental insecurities to show that the most marginalized groups were also the most affected by the floods.
Climate change has played an important role in causing large-scale floods across central India, especially the Mumbai floods of 2005. During 1901–2015, there has been a three-fold rise in widespread extreme rainfall events, over the entire central belt of India from Mumbai to Bhubaneswar, leading to a steady rise in the number of flash floods. The rising number of extreme rain events is attributed to an increase in the fluctuations of the monsoon westerly winds, due to increased warming in the Arabian Sea. This results in occasional surges of moisture transport from the Arabian Sea to the subcontinent, resulting in widespread heavy rains lasting for 2–3 days. The Mumbai 2005 floods also occurred due to moisture surge from the Arabian Sea, and the heavy rains were not confined to Mumbai but spread over a large region across central India.