Rapidly growing Chennai submerged by rare extreme rainfall event

The document analyzes the devastating floods in Chennai on 1 December 2015, which killed over 470 people. While no measurable effect of human-caused emissions was detected for this specific event, the report highlights that unplanned urban growth, encroachment on water bodies, and poor infrastructure management significantly increased the city's vulnerability. Key impacts included the destruction of 4.92 lakh houses and the closure of Chennai Airport for five days. The flooding was exacerbated by the necessary release of water from the Chembarambakkam reservoir to prevent a breach, though the timing of this release was questioned by residents.

• An extreme rainfall event on 1 December 2015 in Chennai resulted in more than 470 deaths and caused the city to come to a standstill.
• Scientific analysis detected no measurable influence of human-caused emissions on the specific one-day extreme rainfall event of 1 December 2015.
• The severity of the flood impacts was driven by human and planning failures, including inadequate flood zone planning, lack of timely desilting, and the establishment of large-scale settlements in low-lying areas.
• Urban development and population growth led to the encroachment of the Adyar and Cooum rivers and other water bodies, increasing flood vulnerability despite a general trend of decreasing rainfall over the last 20 years.
• The flooding was caused by a combination of rainwater accumulation in the north and the overflow of the Adyar and Kosasthalayar rivers in the south, the latter triggered by the release of water from the Chembarambakkam reservoir to prevent it from being breached.

APA

Singh, R., & Arrighi, J. (2017). Rapidly growing Chennai submerged by rare extreme rainfall event. Climate and Development Knowledge Network. https://cdkn.org/sites/default/files/files/Rapidly-growing-Chennai-submerged-by-rare-extreme-rainfall-event.pdf

Chicago

Singh, Roop, and Julie Arrighi. Rapidly growing Chennai submerged by rare extreme rainfall event. Climate and Development Knowledge Network, 2017. https://cdkn.org/sites/default/files/files/Rapidly-growing-Chennai-submerged-by-rare-extreme-rainfall-event.pdf.

Wikipedia

{{cite report |last1=Singh |first1=Roop |last2=Arrighi |first2=Julie |title=Rapidly growing Chennai submerged by rare extreme rainfall event |publisher=Climate and Development Knowledge Network |date=2017 |url=https://cdkn.org/sites/default/files/files/Rapidly-growing-Chennai-submerged-by-rare-extreme-rainfall-event.pdf |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{singh2017rapidly, author = {Singh, Roop and Arrighi, Julie}, title = {{Rapidly growing Chennai submerged by rare extreme rainfall event}}, institution = {Climate and Development Knowledge Network}, year = {2017}, url = {https://cdkn.org/sites/default/files/files/Rapidly-growing-Chennai-submerged-by-rare-extreme-rainfall-event.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }