Life under a retaining wall

Most people migrating to Mumbai in search of work and other opportunities are from the poorest parts of north India. They do not have the means to buy or rent formal housing, and end up living in makeshift homes in hazard-prone areas, especially on the hillocks of Kurla, Chembur, Ghatkopar, Sakinaka, Vikhroli and Bhandup.

Constructed at the foot or the edge of these hillocks, these houses have poor foundations and are made from temporary materials. The haphazard unplanned construction, compounded by the cutting away of hillocks and the surrounding flora for development, makes these areas susceptible to landslides during the monsoons each year and poses a huge threat to life and property.

A 2010 report by the School of Planning and Architecture states that 9.5 per cent of Mumbai’s population lives in landslide-prone areas.

The Brihanmumbai Municipal Corporation and other state agencies have constructed retaining walls in various places across the city but not all the vulnerable places have been adequately safeguarded against landslips. While evacuation of people from these areas is considered the most viable solution to reduce risks, the hesitancy on the part of local residents to leave their homes, however unsafe, and the absence of an alternate disaster-preparedness plan means that Mumbai continues to witness such disasters and its attendant loss of lives every monsoon.

Over 291 landslide-prone areas, 1 lakh people at risk

The BMC’s annual pre-monsoon survey shows that there are 291 landslide spots across Mumbai. More than half, or 152 of these landslide-prone areas, are in Vikhroli and Bhandup.

Environmental and urban activists say that continuous clearing of forests, new construction of shanties, flattening of hill slopes is causing destabilization and erosion of soil, which is making them more prone to landslides.

The exploitation of hills over the years has also led to an increase in landslide-prone areas from 285 in 2016 to 291 in 2021.

“The government needs to show urgency in the rehabilitation of these slum dwellers in a bid to protect their lives as well as preserve the city’s hills, which are being encroached upon at a rapid rate,” Anil Galgali, a Right to Information (RTI) activist, said. Galgali has been following the issue of rehabilitation of slum dwellers and construction of retaining wall on hill slopes.

According to data obtained through RTI enquires, Galgali said over lakh slum dwellers are living in “unsafe” locations. “Between 1992 and 2021, 290 people died and more than 300 were injured in landslides. The Mumbai Slum Improvement Board, which conducted a comprehensive survey in 2010, had recommended relocating the slum dwellers but nothing much has been done in these many years. The construction of retaining walls is also lagging behind,” Galgali said.

As per the standard operating procedure (SOP) of the BMC’s disaster management cell, just before the rains, civic officials issue notices to the slum dwellers living in “dangerous” landslide-prone areas, urging them to move to safer places till monsoon ends.

In 2020, a report published from the Geological Survey of India (GSI) had pointed out that at least six locations in the city are “highly vulnerable landslide” zones: the hill slopes of Bhandup, Vikhroli Parksite, Kurla, Mulund, Jogeshwari, and Chembur.

Following this, the BMC’s disaster management cell had directed all ward officers, collectors of city and its suburbs and the Maharashtra Housing and Area Development Authority (MHADA) to take up preventive measures, like construction of retaining walls.

Challenges to relocation

After the two landslides in Chembur and Vikhroli last month killed 29 people and left another six injured, the state government once again decided to speed up construction of retaining walls at hill slopes to prevent landslides and rehabilitation of slum dwellers who are living very close to these highly dangerous sites. But rehabilitation of slum dwellers and protecting hills from further encroachment is more complex than it appears.

Affordable housing or houses for people from economically weaker sections (EWS) is a distant dream in Mumbai which has the costliest real estate in India.

As per Census 2011, over 50 per cent of Mumbai’s population lives in its slums. People living in these areas mostly do unskilled odd jobs, like painting, carpentry, or work as security guards, house helps or drivers to make their living. These people usually prefer to work in the high-rise buildings located nearby the slums.

Whenever there is discussion on rehabilitation of these slum dwellers from landslide-prone areas, many of them refuse to move out fearing loss of livelihood. “I make papads and sell them in Antop Hill and GTB Nagar areas. If we are moved to some other place, I will lose all my income as I have to start from zero at a new place where nobody knows me. Here, I have been living for the last 30 years and can feed my family with my income from selling papads,” Sakubai Kamble, (60), a resident of Antop Hill near Shaikh Mistry Dargah, said. A landslide in 2013 had killed five persons in the area. Sakubai’s house was also damaged in the incident.

Most of these slums have political support as they are crucial vote bank. If relocation takes place, then the voter base could be disturbed. “For elections, like corporations and Assembly, every small pocket of the voter base is important. These slums have political patronizing due as they are vote banks,” a senior official from BMC said.

In some cases, meanwhile, the redevelopment of these slums have been stuck for many years even after houses were demolished. “In the Parksite area, a part of the slum was demolished for redevelopment under the SRA scheme. The residents were given rent and promised a new house in three to four years. Ten years have passed since but there is no sign of development. Such cases scare the slum dwellers,” Sandeep Yeole, an activist with Ghar Bachao Ghar Banao Andolan, told The Indian Express. “The fear of being stuck in transit camps for years or becoming once again homeless, discourages people from rehabilitation.”

Officials from the BMC said these hillocks fall under multiple agencies, including the forest department, collectorate, MHADA and BMC. The lack of a single unified policy to handle these landslide issues is what has led to landslide accidents a regular feature in Mumbai.

Retaining walls as a solution

Retaining walls are structures designed to restrain the soil. They are normally used in areas with steep slopes or where the landscape needs to be shaped severely for construction. These walls have been found to be a very efficient solution against landslides. In Mumbai, the MHADA has the responsibility of constructing such walls. Over the years, however, questions have been raised on the structural stability of such retaining walls in Mumbai.

Last month, a landslide hit New Bharat Nagar in Chembur despite a retaining wall in the area. Corporators have blamed absence of regular structural audits after the construction of these walls for such incidents.

“Although there was a retaining wall, a landslide happened in Chembur. This raises questions over the quality of construction of the wall. Along with construction of new walls, there is a need for (structural) audit of the existing ones. As a disaster management authority, the BMC should ensure that these walls are checked,” Prabhakar Shinde, BJP group leader in the BMC and corporator from Mulund, said.

Maintenance, MHADA officials, said was yet another challenge as in many cases slum dwellers have encroached upon these walls. “The purpose of retaining walls is to prevent further erosion of soil from hills that have been triggered by construction of slums but in many areas, these have been used as one side of the wall or as the foundation for construction of some huts. There are drain pipes in these walls to allow unobstructed flow of rainwater, but that also, in some cases, have been blocked by residents,” a MHADA official said.

While evacuation seems to be the only feasible option for saving the lives of thousands of slum dwellers living in such areas, the evacuation rate is almost negligible. Also absent is a risk-communication mechanism in the state to warn the residents.

The lack of a participatory platform through which both the state and the local residents can reach out to each other has meant that these accidents continue to happen on an annual basis in the city.

WHAT BMC SAYS

Mumbai: Alarmed by the two landslides in a single day and the high death toll, the civic corporation, under which the city’s disaster management cell functions, called a review meeting with agencies such as MHADA, collector’s office, MMRDA, and PWD to take stock of its mid-monsoon preparation. Since these landslide-prone sites fall under different agencies, the BMC has asked for better coordination between all of them to expedite construction of new retaining walls, repair of existing and rehabilitation of slum dwellers.

The BMC has decided to appoint a consultant to conduct a survey of landslide sites and prepare a report on preventive measures for landslides. They will also find out exactly how many families will need to be rehabilitated from risk zones. According to officials, approximately 20,000 people are living in high-risk landslide sites.

As per a Geological Survey of India (GSI) report on landslides in Mumbai, six zones — Kurla, Chembur, Mulund, Jogeshwari, Vikhroli Park Site (Ghatkopar) and Bhandup – have been marked as ‘highly vulnerable landslide’ areas. There are 20 locations in these six zones. “Our primary concern is to find out immediate measures to prevent landslides. The consultant appointed for survey will suggest measures like strengthening of existing walls and construction of new retaining walls, drains and hill slopes. The entire slum colony will not be relocated only those who are under high risk, affected due to proposed construction of retaining walls or drains,” Suresh Kakani, additional municipal commissioner, in-charge of disaster management cell said. Earlier, state Guardian Minister Aaditya Thackeray had held a meeting with all agencies to expedite all backlog on landslide protection walls and work on auditing the vulnerability of the region. Thackeray was not available for comment. — LAXMAN SINGH