The Indonesian capital's car-free days have been the source of much fanfare. The Ministry of the Environment and Forestry credited car-free days for improved air quality. The events, which are held on Sundays along Jalan Sudirman and Jalan Thamrin, were welcomed as a much-needed chance to get outdoors in a city with few public parks.But car-free days are little more than "an emergency band-aid on a profusely polluting limb," argued a recent op-ed in Scientific American. That's because car-free days, even when they are as successful as those in Jakarta and Paris, often address only part of the problem. While the events may promote healthy and Earth-friendly modes of transportation like biking or walking, cities need to implement sweeping policies that tackle the root-cause of rising air pollution, the op-ed explained.
So what does that mean for Jakarta? Banning diesel cars is a good start. Diesel fuel is incredibly bad for the environment. It releases 15 times more pollutants than regular gas alone, according to a study by researchers from the University of California Berkley. Cities as far-flung as Madrid and Mexico City have already pledged to ban all diesel vehicles from the city in order to fix worsening air quality. Tokyo banned the vehicles way back in 2000, although cleaner diesel autos have made a surprising comeback in Japan in recent years.In Jakarta, the city's fleet of rusted Kopaja and MetroMini buses run on diesel. Same with older TransJakarta buses (although they do use a diesel, biodiesel mixture). But there are also some forgotten contributors to diesel fuel pollution. Power generators, a necessity is a city where the electricity can, at times, suddenly switch off, use diesel. Same with the trucks carrying freight to the city's ports, many of which idle in long lines outside Tanjung Priok. It's no surprise that North Jakarta has some of the worst air quality in the city. Commercial vehicles were found to be among the largest polluters of numerous cities worldwide.Vehicles are responsible for as much as 70 percent of the air pollution in Jakarta, according to studies. The city is currently the largest in the world without a mass transit rail line, but the capital's long-awaited MRT line is currently under construction. Phase one of the project is costing the city $1.7 billion USD and it will link Lebak Bulus, in South Jakarta, with Bundaran HI, in the city's center.It's a victory for mass transit advocates, but it will be a while before the city undergoes a dramatic change. Phase one of the MRT system misses the city's east and west—both the most populous parts of the capital. That's why less sexy solutions, banning diesel cars, buying electric buses, and increasing a city's walkability (which in Jakarta would mean actually building sidewalks you can walk on), are all important, but often overlooked options.So next time you're walking down Jalan Sudirman on a Sunday morning remember, it's healthy and better than nothing, but one day a week without cars on two streets isn't going to fix this city's air quality.