Under the Mumbai Pothole-Free Roads initiative, the Brihanmumbai Municipal Corporation has launched a road concreting project. Out of the 700 km of roads planned for concreting under Phase 1 and Phase 2, 576 km of roads are being concreted so far, achieving about 81% of the target. As an integral part of the concreting project, soak pits have been constructed to effectively manage rainwater and promote groundwater recharge. Accordingly, a total of 681 soak pits have been completed so far in the three divisions of Mumbai City, Eastern Suburbs and Western Suburbs. These soak pits will help in collecting rainwater in the ground and will also help in reducing the pressure on the drainage system.

The implementation of the road concreting project has become a major milestone in modernising Mumbai’s transport system. The project is helping to make traffic on major and secondary roads of Mumbai smoother, faster and more orderly, and the daily commute of citizens has improved significantly. So far, 576 km of roads have been concreted and all these roads have been opened for traffic. The project is being implemented within the stipulated time frame, strictly adhering to quality standards. The Mumbai Municipal Corporation administration, headed by Municipal Corporation Commissioner Ashwini Bhide, has launched a comprehensive cement concreting project to improve the quality of infrastructure in Mumbai. Due to which, travel on the roads is becoming easier. There are very few incidents of potholes due to rain on concrete roads and the maintenance costs have also come down. Apart from this, concrete roads last longer. The reason is that the citizens of Mumbai are getting pothole-free roads. Its long-term positive effects are being seen. To ensure that natural drainage of rainwater is uninterrupted due to concreting and to accelerate groundwater recharge, cesspits have been developed under the project.

Additional Municipal Commissioner (Project) Abhijeet Bangar said that special attention has been paid to natural drainage of rainwater and groundwater recharge while implementing the road concreting project.

It is planned to construct cesspits during the road work to allow rainwater to seep into the ground. These cesspits store rainwater and help it slowly infiltrate into the ground, which recharges the groundwater reserves. Filter media such as stones, gravel and sand are used in cesspools. Rainwater collected in roads or drains is diverted into these drains and from there it infiltrates into the deeper layers of the soil. This helps in storing rainwater locally without wasting it and helps in maintaining the groundwater level. It also helps in reducing the amount of water logging during heavy rainfall and aids in drainage system in urban areas. The completed concreting work has completed a total of 681 cesspools in Mumbai city, eastern suburbs and western suburbs by March 2026. While concreting of all remaining roads in Mumbai is being completed, more cesspools will be constructed along with it. This will help in developing a storm water management system across the city.

Pot filling method
In the construction of cement concrete roads, pits are made at desired locations to drain the rainwater collected on the road quickly into the ground, recharge the groundwater and prevent water from accumulating on the road surface and damaging the road. First, a pit of approximately 1.00 to 1.50 m diameter (circular) or 1.00 × 1.00 m to 1.50 × 1.50 m (square) size and 1.50 to 3.00 m deep is dug at the selected location for soaking. After the excavation is complete, the bottom of the pit is placed on natural soil without concrete, so that water can easily penetrate the ground.

Then a layer of large gravel 40 to 60 mm thick is placed at the bottom of the pit. On top of this, 20 to 40 mm. Gravel and finally 6 to 20 mm. A layer of gravel or coarse sand of the desired size is filled. Due to these layers, the water is filtered and gradually absorbed into the soil. Honeycomb brick construction or perforated RCC rings are installed on the sides of the pit due to which water also enters the soil from the sides and the absorption capacity is increased.

To carry water from the roadside drain or water channel to the absorption pit, two PVC or RCC pipes of 110 mm to 160 mm diameter are connected with a suitable slope. To prevent silt, plastic, garbage or other solids coming with the water from entering the absorption pit and clogging it, a silt trap or silt chamber is prepared before the pipe. This silt trap needs to be cleaned periodically.

A manhole cover is installed at the top of the absorption pit by providing an RCC slab of about 100 to 150 mm thickness. The location of the absorption pit is