How Climate Change is highlighting India’s poor Urban Planning and the way forward

What do Bengaluru, Guwahati, and Gurugram have in common? Well, before you say that they are all names of fast-developing cities in India, the answer lies in the fact that all these cities witnessed intense and unprecedented urban flooding this year aggravated by climate change in the form of extreme rainfall within a short span of time. 

Guwahati, the capital city of Assam which is often termed the ‘Gateway to the Northeast’, witnessed unprecedented rainfall followed by urban flooding in the months of May and June this year. Assam and Meghalaya recorded the highest June rainfall in 121 years with 858.1mm of precipitation, according to IMD data. Heavy rainfall witnessed during the period at Guwahati, lying along the Assam-Meghalaya border, means the city received a major share of it. The city’s residents were trapped in their houses for weeks and relief-rescue operations had to be conducted just within a kilometer of the capital Dispur. This led to the loss of lives even and landslides were reported from different parts of the city as extreme rainfall played havoc in the region. 

Bengaluru witnessed torrential rains in August and September causing severe flooding in several areas. People of the city found themselves trapped in their homes as water levels rose around them dramatically flooding entire basements and even the ground floors of apartment buildings.  According to reports, the city received a record-breaking 180 mm of rainfall in a span of three hours in a day. The Bengaluru Urban district received 79.2mm of rainfall on September 4 and September 5 recording a 1,660% excess. 

Around a week before, Delhi-NCR witnessed incessant rainfall bringing the Millenium City, Gurugram, to its knees. Several major roads and the Delhi-Gurugram expressway were inundated after more than 140mm of rainfall brought life to a standstill in the region. According to reports, Gurugram on September 20, received 54 mm of rainfall and the IMD also issued an ‘orange alert’.

A deadly combination: Poor Urban Planning and Climate Change induced extreme rainfall 

The main cause of urban flooding is a poor urban drainage system that is inefficient and unable to carry the stormwater generated from rainfall. Haphazard and indiscriminate urban sprawling and unplanned infrastructure development are responsible for drainage failure besides, the inefficiency of engineers and the management system concerned. On top of that climatic changes like extreme rainfall has made matters worse. 

“Climate change may also play a role in making urban floods more intense and more hazardous. In all three cases cited above, extreme rainfall was reported from various locations in the cities concerned. The rainfall amounts were larger than twice or thrice the long-term normal rainfall. The drainage networks and their capacities were not designed to channel such large flows triggered by the extreme rain episodes,” said Dr Partha Jyoti Das, Senior Climate-Environmental Scientist and the head of the ‘Water, Climate and Hazard Division’ of Aaranyak. He is also the in-house expert for Climate Fact Checks. 

Natural drainage, once jeopardized, is difficult to compensate

In the case of India, in most cities, the natural drainage systems have been destroyed due to unwise urban development. Earlier, the natural waterways worked efficiently by carrying the surface run-off generated from rainfall to various sinks like rivers, low-lying swamps, and other types of wetlands. The cities remained flood free or experienced moderate flooding, which was easy to cope with before they started to get blocked due to human interference. 

After that, attempts have been made to introduce new drainage systems or even completed in many cases but end results have been far from satisfactory. ‘Natural drainage, once jeopardized, is usually difficult to compensate fully through engineered drainage structures. In most cases, the built-up drainage arrangements could not fully replace the original natural drainage,” Dr Das said. 

“The natural stormwater reservoirs that are available generally in the form of wetlands, lakes, and rivers help in storing and draining the rain-induced runoff, thus moderating the menace of floods in cities. If such sinks are land-filled, silted, or converted to other land use types, the stormwater gets blocked and flooding increases,” Dr Das further added. 

Climate risks have long been overlooked in city planning

The present style of urban planning in India rarely takes into account climatic changes and risks. Most of the planning, whatsoever done, does not equip a city to counter climate risks like extreme rainfall events. This has been seen and reported in case of all the cities mentioned at the beginning of this write-up. 

Lubaina Rangwala, who is the program head of urban development at the World Resources Institute (WRI) commented that the lack of inclusion of climate and environmental risks in city planning is one of the reasons for the unprecedented situation in Bangalore this year. 

“It is difficult to decide whether Bengaluru is witnessing nature’s fury or a man-made disaster, but its devastating impact is out there for all of us to see. Environmental and climate risks have long been overlooked in city planning and, despite such disasters, it is yet to be mainstreamed in our masterplan,” Rangwala was quoted as saying by News18.

According to a Comptroller and Auditor General (CAG) report on the management of stormwater in the Bengaluru urban area, the total length of two stormwater drains in the Koramangala and Vrushabhavati valleys have nearly halved over the past century. Since stormwater drains play a critical role in preventing floods, the result is not surprising at all. The report revealed that some drains had been covered and encroached on, and in some cases, illegal constructions have even been allowed to be constructed on them.

In the case of Guwahati, an Indian Express report clearly explains how clogged drains and human encroachment combined with a week’s rainfall brought the city to its knees this year. Some of the most flood-prone settlements of the city actually used to be low-lying grasslands and wetlands which later got encroached upon. These regions are the first to get flooded now whenever there are extreme rainfall events. Also, the natural drainage system that the city used to have in the form of rivulets no longer exists as human encroachment and plastic pollution have transformed them into narrow clogged arteries of the city. 

In Gurugram, rapid urbanization and concretization have led to the blocking of natural drains or the natural course of water leading to depleting groundwater levels. This has not only made the city incapable of handling climate risks like extreme rainfall events but also made it prone to urban flooding. 

Chetan Agarwal, an independent environment analyst based in Gurugram, wrote in Hindustan Times, “Gurugram has two primary local water problems – declining groundwater levels, and extensive waterlogging and flooding in the city. The solutions for both these problems are largely the same – protecting the spaces such as the waterbodies, wetlands and nullahs that can hold and recharge the water, and protecting and especially lowering the green spaces such as home gardens, parks, and green belts so that their capacity to temporarily hold some of this rainwater and recharge the same is increased.”

The way forward

The way forward is reformed urban planning that takes into account climate changes and risks. Dr Das said that the need of the hour is to reform urban planning with a scientific approach, pragmatic policy, and climate-sensitive outlook. 

In the case of the water bodies, they need to be restored to their original capacities wherever possible ensuring protection in the future. 

“The natural waterways, wetlands, and rivers/rivulet/stream as far as possible; remove the encroachment, clean the water bodies, remove pollution, regenerate biodiversity (aquatic flora and fauna) need to be restored. The water bodies need to be protected and conserved from future abuse and misuse. An integrated solid water management system should be introduced so that garbage does not litter water bodies. The water carrying capacity of the natural water bodies and all sinks that receive urban outflows need to be maintained,” Dr Das said. 

Dr Das also stressed on the need to study local climatic trends and monitor changing rainfall patterns. 

“The local climatic trends should be studied at least for the last 30 years and changing rainfall patterns need to be monitored. Future climate scenarios of rainfall and urban inundation should be produced using robust hydrological modeling tools,” he added.