Railway officials carried out a new oxygen injection method to clean a 250-metre stretch of the Dadar–Dharavi (DD) nullah during pre-monsoon work in Mumbai. This is the first time such a technique has been used. This was done so that workers could safely enter and remove heavy silt from the blocked section.
The nullah connects the Mithi River with railway culverts that carry rainwater away from railway tracks. The section beneath the Matunga railway workshop has long been a major problem area, as it comes under both Western Railway and Central Railway zones.
The Matunga-Dadar stretch has a history of waterlogging during heavy rains. During heavy rains, it often gets clogged with silt, debris, and decomposing waste. This reduces water flow and leads to backflow. Water then collects on the tracks and slows down drainage after floods. Train services are also affected.
As per sources, cleaning this section has been difficult for many years. Harmful gases like methane collect inside closed nullahs and gutters, and it makes it risky for the workers. To address this, engineers used heavy-duty air blowers. These blowers pushed out methane and filled the covered section with oxygen before workers entered. This reduced the danger inside the nullah. With this system, the cleaning work was completed in about 12 to 15 days.
After oxygen was pumped in, conservancy workers entered the nullah and carried out desilting work. The Brihanmumbai Municipal Corporation (BMC) also supported the operation. Officials said this approach helps in places where direct access is difficult. In some sections, the top was opened to allow gases to escape faster.
Super-sucker machines were also used during the operation. These machines removed large amounts of silt, floating waste, and debris. The buildup had reduced the drainage capacity of the nullah over time. After cleaning, the original drainage flow was restored. Vegetation and waste were also cleared from the area extending under the Matunga workshop up to the Railway Protection Force barracks. Water flow into the Mithi River through the culverts improved significantly after this work.
Along with cleaning, the railways also worked on infrastructure upgrades. Track levels were raised in some sections. Between Matunga and Mahim, railway tracks over a 100-metre stretch were lifted by about 5.5 to 6 inches. Drainage systems were also improved, and monitoring systems were installed.