BMC to install 27 floodgates along Mithi river

Mumbai: All harried ground-floor residents, especially those in Kurla’s LBS Marg, who had to vacate their homes every time the Mithi river overflowed, can now breathe easy. The BMC plans to install 27 floodgates in the tidal influence zone from the domestic airport area to Mahim Causeway to provide succour to residents on river banks and in low-lying areas, especially in Sion, Chunabhatti and LBS Marg.

Tenders for Phase 3 of the Mithi River Development and Pollution Control Project will be invited in 10 days. The work will begin from the river stretch at Kurla’s CST Road bridge to Mahim Causeway, including the Vakola leg of the river, and includes the construction of a sewer line, a retaining wall and service roads. Sewer pumping stations will be installed, and there will be interceptions and diversion works to divert the dry weather flow of various outfalls/nallahs into nearby municipal sewer networks. Also on the anvil are 8.8 km of beautification, including promenades and allied works.

A civic official from the BMC’s sewage department in charge of the Mithi river rejuvenation said that 27 mini pumping stations would be installed at the outfalls. “Generally, for conventional pumping stations, we need to acquire additional land but for this project, we don’t,” he said. The civic official reiterated that the low-lying areas in the tidal zone from the airport to Mahim Causeway would be taken up for the project, which is a good 7.77-km stretch.

“On this particular stretch, the riverbed is flat,” he said. “The problems happen when high tide and heavy rainfall come together. In the past, the Mithi river could not take the storm water coming from the catchment areas at a time when it was also submerged with its own tidal waters. To tackle this particular situation, we will provide floodgates with pumps at the mouth of each outfall.

“The floodgates will be closed during high tide to prevent the entry of water into the stormwater drains,” he continued. “Conversely, during low tide, the floodgates will be opened to allow stormwater to flow into the river. The floodgates will be deployed during high tide in the monsoon, which will help the excess water from drains to be pumped out. This will provide relief to the Dadar-Dharavi catchment area, LBS Marg in Kurla, Sion and Chunabhatti.”

While the estimated cost of the project has not yet been disclosed, all residents of affected structures from Mahim Causeway to the airport, who are legally entitled to alternative accommodation, will be rehabilitated. The estimated deadline for completion of Phase 3 is three years.

In 2017, BMC had appointed a consultant, M/s Frischmann Prabhu (I) Pvt Ltd to suggest short-term and long-term measures to control the pollution of the Mithi river under the Mithi River Pollution Control Project. After survey and study, the consultant had proposed short-term works and long-term works in four different phases to divert the dry weather flow of about 285 MLD discharging into the river to the municipal sewer system.