While there no current studies to show what is the amount of fuel being saved or carbon monoxide emissions reduced, the studies done for the much smaller Oval Maidan-Churchgate-Virar and CST-Panvel elevated corridors give a clue.
Mumbai might take the creaking, bursting-at-the-seams suburban local system for granted but it is possibly the biggest reason why Mumbai, despite being among India's biggest and busiest cities, isn't as polluted as some of its smaller counterparts. The fact that all 3000-odd local trains run on 25,000 Volt Alternating Current (AC) means the city avoids nauseating fumes it would otherwise have to bear from fossil fuels.
While there no current studies to show what is the amount of fuel being saved or carbon monoxide emissions reduced, the studies done for the much smaller Oval Maidan-Churchgate-Virar and CST-Panvel elevated corridors give a clue.
According to a preliminary study of the Oval Maidan-Churchgate-Virar elevated corridor, the line, once operational from 2019, would reduce the number of vehicular trips over the route by 7.7 lakh daily. Mumbai sees some 14 millions vehicular trips every day and the experts who prepared the feasibility of the project had estimated that around 10 per cent of all people using cars, taxis, rickshaws or buses along the route would have switched to the elevated corridor.
In fact, of the 27,500 people who would be using the elevated corridor during every peak hour, 2,500 people would be those who would have previously been road-users. The environmental impact of the rail corridor reducing these vehicle trips was just a drop in almost 41 tonnes of carbon monoxide emitted every day.
Similarly, the CST-Panvel elevated corridor would have brought about a reduction of 6 lakh vehicle trips daily if it would have started in 2019. The reduction in carbon monoxide emissions on a daily basis would have been 7.55 tonnes, according to the feasibility study of the project. Both the projects would have seen a daily average fuel reduction of 60,000 litres as well.
It's a lot of people Mumbaikars travel with
CR - 145 crore passengers per year which works out to 39.7 lakh passengers per day
WR - 128 crore passengers per year which works out to 35 lakh passengers per day
Population of India as per Census 2011 - 121 crore. Therefore, between them CR and WR carry 273 crore passengers per year, which works out to transporting all of India 2.25 times or the entire population of Maharashtra (as per Census 2011 is 11.2 crore), which works out to 24.8 times or population of Mumbai (1.9 crore as per Census 2011) some 143 times
Elevated corridor
Reduction in vehicle trips per day
CST-Panvel - 6 lakh
Churchgate-Virar - 7.7 lakh
Reduction in CO2 emissions per day
CST-panvel - 7.55 tonnes
Churchgate-Virar - 41 tonnes
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