Shifali Chib & Sundeep Pandita
Flooding is an ongoing problem that affects many locations across the world, inflicting enormous damage to property, infrastructure, and, most importantly, human lives. Rapid climate change has resulted in more severe and erratic rainfall, straining current drainage systems and creating frequent flood like conditions. As urbanization accelerates and climate change worsens weather patterns, the risk of floods grows. Climate change and weather extremes are expected to have a substantial impact on cities with poor drainage systems in the near future. The old drainage systems have been dismantled to enlarge the roadways, resulting in waterlogging.
On July 27, 2024, the waterlogging incident at Rao Coaching Institute in Delhi’s Old Rajendra Nagar serves as a sharp reminder of the repercussions of insufficient drainage infrastructure. Heavy rainfall resulted in quick increase in water level. The narrow drains surrounding the institute were unable to handle the downpour, causing catastrophic flooding that halted activities and threatened lives and killed three young aspiring civil servants. This incident underscores the critical need for infrastructure changes to avoid such incidents in the future.
The city of Jammu, situated on the banks of the Tawi River has been facing recurrent flooding issues particularly during the monsoon season. The road network in the Jammu city suffers badly due to heavy rainfall flooding especially during the monsoon season. One of the key contributors to the flooding problem is the non-existence of suitable drainage and poor maintenance of the nallas in the city.
The khads and nallas pouring from the Siwalik foothills have proven effective in discharging surplus water during flash floods. However, due to increased construction and encroachment in these nallas and khads around the city, their carrying capacity has been significantly reduced, resulting in frequent flooding. The existing drainage system, comprising of numerous nallas, is often unable to handle the massive volume of water discharged owing to constant rains, resulting in overflow and waterlogging in various sections of the city.
The existing drainage infrastructure has not kept pace with the city’s growing population and urbanization, leading to insufficient carrying capacity. Many nallas such as Qasim Nagar nalla, Muthi camp nalla, etc. have been encroached upon by unauthorized constructions and development of parks, reducing their effective width and obstructing the flow of water. Over the time, these channels accumulate silt, debris, and waste, which further restricts water flow. The width of the Qasim nagar nalla was about 10-12 meters before 1990, but it has now reduced to just about 4.5 meters owing to encroachment and construction on the banks. Same is the case with the Muthi camp nalla which was more than 30 m wide near the BSF Golf Course before 1990 and has been reduced to only about 7 m, due to urban construction. In future whenever there is heavy rainfall in the upper reaches these nallas are sure to be flooded and shall be ineffective in handling the massive volume of water which shall result into damage to the infrastructure and shall create havoc.
A well-designed drainage system is critical for minimizing flooding, decreasing waterlogging, improving public health, and protecting infrastructure. Efficient drainage systems help divert excess precipitation and river overflow away from populated areas, lowering the risk of flooding. Narrow drains and nallas, present a substantial difficulty in flood management due to low carrying capacity, obstructions, and maintenance issues. On the other hand, wider drains enhance their ability to convey water, lowering the danger of overflow and flooding.
To successfully minimize impact of floods, it is necessary to have better drainage systems and enlarged drains. All the road networks particularly in the urban areas must have deep drainage system as is being implemented in the case of national highways. As climate change presents new difficulties, proactive investment in sustainable drainage infrastructure will be critical in developing resilient communities that can resist the effects of extreme weather events.
(Shifali Chib is research Scholar & Sundeep Pandita teaches in University of Jammu)
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