- Sewerage, drainage, and water supply systems laid by British empire in Kolkata were a wonder of the age 150 years ago but have not kept pace with modern demands. ADB has worked with the city for more than 20 years on an integrated approach to improvements.
- After two decades of engagement with ADB, Kolkata is on the path toward achieving the shared vision of becoming more livable, greener, more sustainable, inclusive, and resilient.
The state of Kolkata's drainage systems
When the engineers of the British empire laid underground sewerage and drainage more than 150 years ago in Kolkata, it was a wonder of the age. Calcutta, as the Victorian metropolis was called, was only the second city in the world to have such an extensive and centralized sanitation system, after Hamburg in Germany.
“Kolkata’s landmark water supply and sewerage and drainage systems are still operating,” says Neeta Pokhrel, the unit head of project administration for South Asia Urban and Water division of Asian Development Bank (ADB). “But as the city has grown, these systems have not kept up with the pace of modern demands.”
Today’s Kolkata City—the state capital of West Bengal—is home to more than 5.2 million people within its boundaries and some 14.7 million in 2015 in the metropolitan area, making it the third most populated urban area in India. With an average of 24,000 people crammed into each square kilometer, it is also one of the densest megacities in the world.
Early attempts to keep up with the city’s rapid growth were mostly piecemeal. As the city leaders tried to maintain services, they came to realize that what was needed was an integrated and planned approach. With these demands in mind, ADB and the Kolkata Municipal Corporation (KMC) joined forces just more than 20 years ago to improve Kolkata’s urban services.
“The sewerage canals had never been cleaned, and the system badly needed desilting and rehabilitation to alleviate the flooding that Kolkata experienced each monsoon season,” said Sourav Majumder, an ADB Senior Project Officer (Urban). “The trunk sewers in central Kolkata, some silted by 80% over the years with almost solidified deposits, needed urgent attention.”
“The sewerage canals had never been cleaned, and the system badly needed desilting and rehabilitation to alleviate the flooding that Kolkata experienced each monsoon season. The trunk sewers in central Kolkata, some silted by 80% over the years with almost solidified deposits, needed urgent attention.”
Meanwhile, the water system was experiencing estimated system losses of 40%–65% on the way to consumers. And there was not even a map to show where all of the pipes had been laid—some 140 years previously.
Improving Kolkata’s urban services
ADB kicked off its partnership with KMC in 1998 with two grants to strengthen the corporation’s accounting system and to prepare ADB’s first urban sector loan to the KMC, the Kolkata Environmental Improvement Project (KEIP). Since then, ADB has been supporting KMC to improve Kolkata through a series of phased investments and helping plan integrated urban development.
“I was project officer for the first technical assistance grant to support improvement in the accounting systems of the KMC, said ADB’s Director General for South Asia, Hun Kim. “Two decades, five loans, and four grants later, we have come a long way toward achieving the common plans of the KMC and ADB for the city.”
As a first phase of investment, ADB approved the $250 million loan for KEIP in 2000 to make urgent improvements to sewerage and drainage infrastructure that had not been touched or expanded since construction. It also tackled the city’s finances and financial management to better handle urban services and prepared a master plan for the city’s needs.
The project addressed the city’s weakest spots—notably the sewerage and drainage—increasing pumping capacity, refurbishing sewage treatment plants, re-excavating drainage canals and resettling the poor dwellers along the canals. More than 2,800 households were granted titles in the name of their women, while the project also provided gender-secluded water quarters for bathing and laundering, and skills and financial training for women. It helped modernize its age-old financial management systems.
With the first phase completed successfully in 2013, ADB and KMC embarked in 2014 on a larger program of investments, the Kolkata Environmental Improvement Investment Program (KEIIP). This was a $400 million multitranche financing facility split between three loan investments planned between 2014 and 2023. KEIIP focuses on policy reforms and infrastructure improvement to provide better urban services and addresses Kolkata’s vulnerability to climate change.
Toward sustainable urban services
Through KEIP and KEIIP support, the sewerage and drainage systems have been rehabilitated and extended outside the core areas to almost double their original capacity. The canals for treated effluent have been cleaned, existing sewage treatment plants rehabilitated, and new ones are being constructed. Flooding has been addressed to a large extent and fewer streets remain impassable during downpours.
Work is continuing to bring clean water to more people and for longer periods of the day. Plans and ongoing works are aimed at reducing water loss. A large number of slum dwellers who lived around canals and wetlands now reside in livable housing and have more meaningful employment. Solid waste collection and recycling are also being improved.
Taking into account lack of space and high density, technology such as micro-tunneling has been adopted to lay large pipes to minimize disruption. KMC utilized remote sensing and geographic information systems to put all its urban assets, properties and services on one digitized map, and is making it accessible to citizens an interactive e-platform for urban services to its citizens. Municipal finance and urban governance for the city has been strengthened and digitized.
The tasks of bringing fully sustainable urban services to Kolkata are so enormous that gaps still remain. But after two decades of engagement, Kolkata City is on the path toward achieving the shared vision of becoming more livable, greener, more sustainable, inclusive, and resilient.