Green Roofs: A Flood Control Strategy for Urban Cities

A study by CEPT University and IIT Bombay highlights the effectiveness of green roofs in reducing urban flooding. Planting small trees on rooftops can absorb rainwater and mitigate flood volumes. The study cautions about the cost, maintenance, and limited applicability of green roofs in certain areas.

In an effort to tackle urban flooding, a joint study by CEPT University and IIT Bombay has found that green roofs can make a significant difference in flood management—especially in densely populated cities. Green roofs involve planting trees on building rooftops, which helps absorb rainwater, subsequently reducing flood volumes.

The research highlights the problem as cities expand with more concrete structures, significantly diminishing ground areas that absorb water. This leads to urban flooding and water-logging in low-lying urban spots after heavy rainfalls.

While the study champions green roofs as an effective measure to curtail floods, it also points out challenges such as the additional expenditure, increased building weight, and maintenance needs that green roofs require. Additionally, green roofs are not practical for buildings with metal or concrete sheet roofs, such as slums and low-cost housing. Importantly, the study notes that flood mitigation isn't directly proportional to the extent of green roof installations, as it depends on the drainage network's capacity as well.

(With inputs from agencies.)