BMC to map nullahs, drains to monitor flooding during monsoon

With one eye on a long-term solution to fix the city’s flooding woes during the monsoon season, the civic body has planned a survey of 430km of minor nullahs and 2,000km of road-side drains.

With one eye on a long-term solution to fix the city’s flooding woes during the monsoon season, the civic body has planned a survey of 430km of minor nullahs and 2,000km of road-side drains.

The Brihanmumbai Municipal Corporation’s (BMC) Rs12.90 crore project will include the Geographic Information System (GIS) mapping of drains and nullahs, which will be uploaded on software that is accessible to civic officials on a real-time basis.

A civic official, on the condition of anonymity, said, “There will be around five teams at various locations. Each team will survey about 1.5km of nullahs a day. This will be a two-year-long exercise.”

The standing committee will consider this proposal in its meeting next month and the work order for the project is expected to be given soon after.

Laxman Vhatkar, chief engineer, storm water drains, said, “The project will be tabled in front of the standing committee in a month’s time and because the nullahs have already been cleaned, the work can begin this monsoon.”

Year after year, the BMC undertakes nullah cleaning work worth Rs90-100 crore, just before the rain starts, to avoid flooding. The cleaning is rarely foolproof, with the silt going back into the drains and nullahs.

Currently, the BMC starts the pumps to drain the water, but only when flooding is at peak. With the mapping and the survey of these nullahs and drains, however, there will be an early alert system to help the BMC start pumps even before flooding begins.

The project will also include mapping underground utilities to help implement future storm water drain projects. The data on the major nullahs, too, will be uploaded on the software, making it easier for the BMC to verify complaints.

The consultant will train BMC engineers on how to operate the software and will have to submit a detailed report after two years. Around 300 flood-prone spots on the drains will be marked.