Introduction
The Rail Wheel Factory (RWF), is a unit of Indian Railways, established in 1984. It manufactures and supplies 95% of the wheels, axles and wheel sets required by Indian Railways. It is located in Yelahanka (13.10849, 77.5868) on a 191 acre campus. It is categorized as a ‘red’ industry by Karnataka State Pollution Control Board (KSPCB), but it is moving towards becoming ‘green’ through various initiatives. RWF launched a sustainable water management project on World Environment Day, June 5th 2017, and is a zero discharge campus.
Water Demand and Supply
Demand:
- 1500-1800 KLD (kilolitres per day) of water for the plant and two residential colonies
- Of the total, about 200-300 KLD of water is used for cooling inside the plant
Supply:
- Cauvery water (1050 MLD) and treated wastewater (250 MLD) from BWSSB
- Borewells and open wells (50-350 MLD)
The project
The RWF has 2 main areas of concern with regards to sustainability:
- Groundwater seepage in the dust filtration tunnel
- A large amount of water needed for cooling
It has successfully addressed these issues by adopting sustainable water management strategies.
1. Groundwater seepage in the dust filtration tunnel
A wheel is cast every 2 minutes in RWF. This process generates a huge amount of dust. RWF has two sets of Dust Mitigation Plants – Primary and Secondary, to capture the dust and release only clean air into the external environment. The groundwater table there is very high and subsurface water used to seep into the tunnel. This reduced the width of the tunnel and the water also mixed with the dust and choked the filter. This problem persisted for 15 years and required a lot of maintenance. There was a existing open well in the campus, and RWF decided to dig 2 more withdrawal wells (4*25). About 30 KL water is pumped from these wells for use in cooling, and this has helped eliminate the seepage in the tunnel as it pushes down the groundwater table.
2. Harvesting surface runoff
This has been addressed through two measures:
-
Extending the area of the wetland
Since the RWF is a zero discharge campus the industrial muck or waste from 40 years of manufacturing was dumped in a low lying area close to the wetland. Overall more than 500 lorry loads of muck were removed to clear the low lying area to create water bodies and to extend the wetland. The wetland absorbs, holds, and cleans the water and thus helps to recharge the groundwater table.
-
Rejuvenating open wells
RWF decided to revive 4 open wells located in the low lying area. One of these is the Kandaswamy well. About 70 truckloads of muck were cleared from around this well alone. It is located close to and is recharged by the wetland. After cleaning and desilting, its yield increased from 20-25 KLD to 150 KLD.
Three similar wells – Damodar, Somashekara and ETCO were also revived. RWF also dug two new wells to increase the recharge volume and to thus ensure water security during the periods of reduced rainfall. All these wells hold water at less than 5ft from ground level. The water is used for cooling.
RWF has developed a simple sedimentation and filtration system to harvest the surface runoff from the paved area. It has also implemented rooftop rainwater harvesting for the pump house building. Both surface runoff and rooftop rainwater is stored in underground storage tanks and used for cooling purposes.
Impact of these measures
- The demand for BWSSB water reduced from 1300 KLD to 900 KLD. Currently, RWF uses only the water from open wells for cooling
- RWF used to spend Rs. 4 crores annually on BWSSB water. After implementing rainwater harvesting, their annual water bill was reduced by Rs. 65 lakhs
The project was conceptualized and planned by Mr. Ajay Singh, Head of Wheel Plant and Chief Environmental Officer, and executed by the RWF team during 2017-2021.
Here is a video of Mr Ajay Singh talking about the water conservation interventions at the Rail Wheel Factory, and this is a long form of the case study.