WHAT MAKES THE CITY VULNERABLE?

In 2022, Pakistan and India experienced a devastating heatwave and recorded the region’s hottest March since 1901 (CNBC, 2022). Like the heatwave of 2015, the majority of the deaths were concentrated in the Sindh province (World Bank Group & Asian Development Bank, 2021). Matthews et al. (2017) identify Karachi among the most vulnerable cities to increasing extreme heat events. Even under lower emission goals, abnormally high temperature days (which are considered heat waves) are becoming a regular occurrence. Heat waves not only threaten human lives, but they also increase the potential for more extreme and erratic rainfall events, contributing to flooding (Freeman, 2022).

Karachi recently experienced its heaviest rains in almost a century with more than 2.3 inches (60mm) of rainfall, equivalent to an entire months’ worth of rainfall. Thousands of homes and settlements were subsumed and destroyed, with more than 100 people killed (Bhutto, 2020). Monsoons are a common occurrence in Pakistan and the surrounding region, lasting for several months every summer. However, in recent years, climate change has been accelerating its intensity and causing irregular patterns (Saifi & Mogul, 2022). The region has been experiencing back-to-back extreme weather events every year, with more citizens grappling with losing electricity, contracting water-borne diseases, and experiencing food and water shortages.

Sea Level Rise

On top of heavy rainfall, Karachi is facing the threat of a rising sea level given its location along the coast. Rising sea levels impact the environment of coastal areas by causing soil erosion, contamination, flooding, degradation of native mangroves forests, and deteriorating coastal ecosystems. Researchers at the University of Sindh in Jamshoro predict that 26,000 square kilometers of land will be lost if the sea level rises by 0.66 meters, and, 33 percent of the coastal land along with its wetland ecology will be lost in the next hundred years if we continue on the same path (Ali, 2022).

Poor Infrastructure

The poorly maintained infrastructure in Karachi, primarily drainage systems, make the city even more vulnerable to flooding (Anwar, 2012). Malir and Lyari rivers are the two main basins that contribute to about 80 percent of the local surface runoff. Storm water drains (nalas) also carry water from their catchment areas, as a drainage network. However, the nalas were not designed for intense rainfall and are working at reduced efficiencies due to sewage blockages and encroachments (City District Government Karachi, 2007). The government of Sindh constructed the trunk sewers along the main roads, but sewage continues to flow into the storm water drains. Unfortunately, massive estate development in the hills north of the city are further eroding natural drainage channels causing intensified flooding issues for the people living in the south below them.