Delhi Government To Build 'Silt Traps' Along Drains To Prevent Waterlogging

The Public Works Department identified 308 waterlogging points in Delhi during 2023.

New Delhi:

The Delhi government has introduced a comprehensive Drainage Master Plan featuring innovative 'silt traps' along major drains to combat the city's persistent waterlogging issues.

This ambitious modernization initiative for Delhi's aging drainage infrastructure draws inspiration from a highly successful pilot project implemented in Chennai.

"Several years ago, we experimentally installed 'silt traps' in Chennai's drainage system, which resulted in a significant reduction in waterlogging incidents throughout the city," explained Gyanasis Jena, one of the private consultants commissioned by the government to develop the plan.

According to the proposed plan, these traps will be constructed as dedicated chambers positioned at lower levels alongside existing drains. This design allows stormwater-carried silt to accumulate in these chambers, preventing blockages in the main drainage lines, Jena elaborated.

Developed to address Delhi's drainage requirements for the next three decades, the master plan will be executed over a five-year period in two distinct phases.

This strategic approach aims to decrease waterlogging incidents by 50 percent within three years and reduce flood-related accidents by 30 percent within five years.

The implementation phases will focus on critical flood control measures and network expansion with priority integration, overhauling the extensive 18,958 km drainage network currently managed by eight different agencies.

"Silt accumulation in drains significantly reduces their carrying capacity, leading to backflow problems. Our survey revealed the existing drainage network is inadequate for handling stormwater effectively. With the silt trap mechanism, only the designated chambers would require cleaning as they would capture the silt before it enters the main drains," Jena stated.

The plan divides the city into three distinct drainage basins — Najafgarh Basin, Barapullah Basin, and Trans-Yamuna Basin.

Across these basins, the current drainage infrastructure is approximately 50 years old and no longer capable of accommodating Delhi's rapid urbanization and changing rainfall patterns.

The Public Works Department identified 308 waterlogging points in 2023.

Currently, there are 445 documented waterlogging points throughout the capital.