Security Exchange News

Monsoon in Mumbai

28 June 2018

Another monsoon season has arrived in South Asia and with it, the Mumbai Rains have returned. The season typically lasts from June until August but has been known to carry on into September and even October. Every year, Mumbai is one of the worst-hit areas, with flash floods sweeping through the low-lying megacity. Heavy rainfall has been brought to Mumbai again this year by the Southwest Monsoon, killing at least three people on Monday. Seven fatalities have been recorded in the neighbouring region of Thane, where at least five people drowned, one person was crushed by a collapsing wall and another was killed after their car crashed into a road barrier in low-visibility conditions. Thunderstorms have also accompanied heavy rain in parts of Bihar, Gujarat, and West Bengal - raising the total death toll in rain-related incidents this week to at least 19.

The wet weather in Mumbai has caused severe widespread disruption, as the floods have forced many out of their homes and made many roads impassable. Public transport systems have also been forced to suspend operations in certain areas, as the floods have caused significant damage to buildings and vehicles. Approximately 231.4mm of rainfall was recorded within the first 24 hours (Sunday to Monday) by the Santacruz observatory, while around 317.6mm was recorded in the Malad area – the highest amount recorded so far this year within a 24-hour period. Weather warnings have been issued for most central and northern states - including Bihar, Chhattisgarh, Jharkhand, Madhya Pradesh, Maharashtra, Odisha, Uttar Pradesh, and West Bengal - where there remains a high chance of further bouts of heavy rain throughout the next few weeks.

Other parts of India have also been affected by the arrival of the wet season. Last week, widespread floods were reported in Assam, after heavy rainfall caused the Brahmaputra river to flood. At least 31 confirmed fatalities have been reported from the region so far. Over 700 villages were estimated to be underwater and almost 4,000 hectares of crops were also damaged. The authorities allegedly set up more than 450 relief camps for the millions who were displaced by the flooding.

Although the monsoon season brings severe wet weather to the region every year, the intensity and duration of the rain are said to be becoming increasingly unpredictable. Despite the ongoing uncertainty, the same areas tend to be affected by the overall trend showing a gradual increase in the intensity of the monsoon weather. The worst flood to hit the city in recent years was during the 2005 monsoon season. The Maharashtra floods of 2005 killed an estimated 1,094 people - including hundreds in Mumbai, which was brought to a standstill by the floods on 26 July. A staggering 944mm of rain fell within 24 hours, forcing Mumbai’s airports to remain shut for over 30 hours – leading to severe international flight disruption. The situation was made worse by the heavy rainfall coinciding with high-tides. Several other factors also contributed towards the tragedy – such as the inadequate drainage system which failed to cope with the high amount of rainfall and the uncontrolled spread of unplanned suburban developments. The overall damage caused by the disaster was estimated to have caused a direct loss of around 5.5 billion Rupees ($100m; £57m).

Disaster management measures were set up in response to the 2005 flooding; however, many have criticised the local authorities for failing to invest in preventative measures. The low-lying city is prone to flooding during the monsoon season and weather experts believe that the chances of another massive flood could more than double by 2080, with death tolls potentially three times as high. Low-income city dwellers are often among those worst affected by the floods. The majority of deaths in 2005 occurred in informal settlements, which are thought to be home to more than half of the city's population. Even after the heavy rain subsides, stagnant flood water becomes an ideal breeding ground for disease-ridden mosquitoes. Diseases such as malaria, dengue, and leptospirosis often break out - further threatening the low-income population, which typically don’t have access to medicine and healthcare. In the case of this year's rains, several disease-related deaths have already been reported as the city gears up for an onslaught of disease.

According to the Indian Meteorology Department (IMD), the heavy rain is expected to ease off until Friday 30 June, with only intermittent showers forecast. During this time, the risk of contracting water-borne diseases will be especially high, as citizens are likely to venture out into flood water to aid recovery efforts and resume day-to-day activities. However, the IMD also issued a precautionary warning that another bout of heavy rainfall could hit the city again next week.