Despite the recent economic slowdown, it is hard to imagine an India without congested roads, long queues at signals, rickety public transport and decrepit, if any, pedestrian and bicycle infrastructure. By all indications, demand for transport services, like all other commodities is likely to pick up once the economy picks up. Is India poised to satisfy this demand and if so, do we have a guiding philosophy that will help us achieve this objective over the next few decades? Resources are scarce, most Governments, including ours, are operating at very high levels of debt. Under these circumstances, adding capacity (increasing supply) may not always be feasible. It goes without saying that a basic quality & quantity of transport infrastructure is needed but it is extremely important that we know where to draw the line.
Before I start using examples of Indian cities, I would like to present some interesting information on US cities which have a much more superior transportation infrastructure than ours but still face severe congestion during rush hours. INRIX, a traffic data vendor publishes a congestion index for US cities. In this list, Austin (Texas) ranks higher (more congested) than much larger cities like Boston, Chicago and Washington, D.C. In addition, a section of Interstate 35 (a signal-free urban roadway) in Austin (Texas) with four lanes in each direction was ranked as the 14th most congested corridor in the United States per the annual congestion report published by the Texas Transportation Institute. In addition to the 8 signal-free lanes of roadway, this section of I-35 also has a feeder road (signals at various locations) with two lanes in each direction. A small city like Austin (772 square kilometers) with a population of 790,390 ranks higher in congestion rankings compared to even the much larger Houston (1552 square kilometers) with a population of 2,099,451.
As the numbers indicate, Houston is much more dense (people per square kilometer) compared to Austin. This little trivia should give us the encouragement to leverage our population densities, which are much higher than most US cities. Clearly, even 10-lane urban highways begin to start failing as cities grow and the demand for travel increases.
Adding more lanes to a highway has almost never eased congestion in the long run due to a phenomenon called induced traffic. To describe this phenomenon, let me use a hypothetical scenario of two roads in Bangalore, MG Road (black line) and Richmond Road/Rajaram Mohan Roy (red line) as shown in the exhibit below. Let’s assume that MG Road (black line) is extremely congested during rush hours. To avoid getting held up in a traffic jam on MG Road, some commuters are likely to divert to Richmond Road/Rajaram Mohan Roy Road (red line). This happens quite often, traffic tends to seek the state of “equilibrium” amongst the various route choices. To ease congestion, the Bangalore Development Authority (BDA) adds a lane in each direction of travel to increase roadway capacity along MG Road. The new lanes will immediately reduce congestion but it will not take long for people on Richmond Road/Rajaram Mohan Roy Road to realize that MG Road is less congested than their current choice of travel route. This will induce those people to move back to a decongested MG Road because of its new capacity (seeking equilibrium). Over a period of time, we will be back to square one. Just to make it clear, induced traffic isn’t a bad thing. In the MG Road example, the widening allowed more people to travel along the corridor with the same level of congestion as before, i.e., same congestion but more people served.
MG Road (Black Line) and Richmond Road/Rajaram Mohan Roy Road (Red Line)
But what next, do we keep widening MG Road till we reduce congestion? This option obviously isn’t feasible. So what is feasible then? The answer to the question is “Smart Growth” also known as “New Urbanism”.
The west, especially the US adopted and built its cities around the suburbia model where everyone lived in the suburbs and drove in to work in the heart of the city, the Downtown. Many decades and wide urban freeways later, cities in the US are still reeling under severe rush hour congestion. As a result, the US is beginning to realize the side-effects of the suburbia model, i.e., long trip lengths (distance to work, home, shopping etc). This side-effect unfortunately cannot be cured with wider-er freeways. This realization stimulated various research initiatives to identify what went wrong.
In the last decade, there has been a growing realization amongst US’ transportation planners that smart growth could probably provide long term sustainable solutions to our transportation related challenges. Smart Growth relies on mixing a wide variety of land uses (houses, offices, shops) in a small urban area, to efficiently manage (not curb) travel demand. Research conducted by US’ Environmental Protection Agency (EPA) theorized and proved that travel demand is significantly influenced by 5 important “Ds” of development:
1. Density of land uses: Areas that have high densities raise the relative cost of driving your own vehicle in comparison with transit, making the latter more attractive.
2. Diversity of land use: The more diverse the land uses, lesser the need to travel outside the area. Think of a well connected area with jobs, housing & shopping avenues within a small radius.
3. Design elements: These include elements like footpaths & safe roadway crossings for pedestrians, safe & efficient bicycle paths, and a closely spaced grid-like roadway network. Research on this topic indicates that a closely spaced grid-like roadway network tends to be perceived favorably by pedestrians, i.e. encourages walk trips over vehicle trips. A half kilometer stretch of a high speed roadway is more likely to intimidate pedestrians while a half kilometer stretch of roadway with closely spaced junctions is likely to be more inviting for pedestrians and bicyclists. Apply this logic to streets in your city and see which one appeals the pedestrian/bicyclist in you.
4. Destinations: This variable in the 5D planning process represents the attractiveness or vibrancy of an area. Availability of jobs or shopping areas for instance would influence this variable.
5. Distance to transit services: The closer a transit stop, higher the probability of a transit trip in lieu of a trip by personal automobile. There are obviously other factors that influence the decision making process. There may be a bus stop, but does it even serve your destination, and is the bus service comfortable enough are some of them.
A Mixed Land Use & Transit Oriented Development in Gresham, Oregon (Source)
New urbanism, i.e. smart growth has found it fair share of proponents in the US. Civic authorities there are encouraging & incentivizing mixed use developments which comply with the 5Ds and hence reduce the average number and length of motor vehicle trips. The EPA has developed a regression model to estimate the reduction in vehicle based trips due to mixed land use projects. The spreadsheet based model can be downloaded from the EPA’s website. But be aware that the model was validated using data collected in the US and hence is of little practical use in the Indian context.
It is important to realize that congestion is a function of traffic volume on a road and the roads capacity to handle it. Often there is only so much that can be done to increase capacity. But as documented in the EPA-led study, traffic volumes can be reduced without reducing the number of trips (demand). To explain the subtle difference, let me cite an example. Let’s say you live in an apartment complex and you have to go to the nearest convenience store to get a bag of rice.
Scenario 1: The convenience store is located 200 feet from your apartment. You will most likely walk to the store and buy what you want. Scenario 2: The convenience store is located 2 kilometers from your apartment. You will most like drive your car or ride your motorcycle to get the same stuff.
In the two scenarios, assume that no one else in your city changes anything about their travel behavior. In scenario 1, you made one trip to the store but there was no increase in traffic on the road (which is what causes congestion) since you walked on the footpath. In scenario 2, you made one trip and since you drove on the road, the traffic increased by 1 unit (car or motorcycle). Now aggregate this at a higher level and you will see how the 5 Ds of smart development reduce traffic volumes and meet the demand for travel (trip to your destination) at the same time. It is important not to confuse smart growth with the anti-motorization school of thought. The anti-motorization philosophy believes in making driving a costly/difficult task. Smart growth on the other is based on the principle of making walking/bicycling easier than driving. There is a subtle but important distinction between the two philosophies which must be appreciated.
The US is now looking to do what India has always been, a smart growth compliant nation. We have always had houses, vegetable markets, banks & convenience stores in close proximity. That may be changing now with the new fascination with high-speed highways. I am not saying that high-speed highways are not required but we must be wary of not stretching it too far and wasting valuable resources like Austin probably did for a long time.
For example, 12 signal-free corridors (freeways) are being proposed in Bangalore including one between Sirsi Circle and Agara Lake (see map below). A quick search on Google suggests that the distance between these two locations today is 12.5 kilometers, a 30 minute drive if there is no congestion. Anecdotal evidence from Bangalore residents however indicates that this journey is extremely painful and takes as much as an hour and a half during rush hours.
Sirsi Circle to Agara Junction Travel Route
The proposed Sirsi Circle to Agara Junction signal-free corridor is expected to cut this distance down to 8.5 kilometers. More importantly, the corridor is expected to cut down the travel time from 90 minutes to 10 minutes. In all likelihood, the corridor will also connect Bangalore with Electronic City (south-southeast of Madivala Lake in the map above). This project once complete is going to make it extremely attractive for Bangalore residents to live in the heart of the city and travel to destinations near and beyond Agara Lake for work. Precisely what the US did for decades, built their homes far away from their work places and then joined the two with high-speed interstate highways (signal free), almost all of which are jammed during rush hour traffic today.
With these signal-free corridors, Bangalore is inadvertently encouraging its citizens to undertake long journeys to get to their destinations. Besides longer trip lengths (resulting in more fuel consumption and traffic volumes), these corridors will adversely impact whatever little benefit Bangalore’s public transport has to offer. Will buses from Sirsi Circle to Agara Lake take exits from the elevated sections of the signal-free corridor to pick up passengers at bus-stops located on the road below? Or, will buses not use the signal-free corridor at all and travel on the service roads along the entire route? In either case, public transit will suffer, further widening the travel time gap between driving your own vehicle to work versus taking the bus to work. In that case, those who ride the bus today will be tempted to drive their own vehicle (if they have one) on the swanky new signal-free road. Those who cannot afford a personal vehicle on the other hand will have to spend more time traveling to and form work. As a result, the number of personal automobile trips between Sirsi circle and Agara Lake is likely to increase, I don’t know by how much but it will. Besides, there appears to be more than one way to go from Sirsi Circle to Agara Lake. Today, traffic is dispersed along all these various routes between the two ends of this proposed signal-free corridor (“equilibrium”). But as demonstrated previously in the MG Road versus Richmond Road example, a lot of traffic will get attracted towards the new signal-free corridor.
What happens when the signal-free corridor starts to get congested 5, 10, 15 years down the line? Clearly, a signal-free corridor is required to satisfy the immediate demand for travel but it is by no stretch of the imagination a sustainable solution to congestion. It would serve Bangalore better if the civic authorities adopt a comprehensive land use plan that is integrated with its long term transportation plan. Such a plan should be designed to incentivize smart growth, in the form of dense mixed land use townships in the suburbs of the city for instance. These townships would ideally consist of employment destinations (offices, malls, and shops), residences and other important land use types like hospitals and schools. The internalization of trips within such township will encourage shorter trips and also result in an increase in the number of walk or bicycle trips.
In addition to high density mixed use developments in the suburbs, another concept that is gaining ground is “infill development”. This strategy involves tearing down old and sparsely populated neighborhoods, and replacing them with dense high-rise mixed use developments that meet the 5D factors explained previously.
Although it may on occasions be a little difficult to replicate infill development projects in India due to presence of historical structures & buildings in the vicinity of our city centers, it is certainly not beyond us. Let’s take Bangalore as an example again. Take a close look at the area surrounding Sirsi Circle in the aerial photograph below.
Existing Land Use Near Sirsi Circle
The area around this junction appears to be low-rise apartment complexes (guess based on Google imagery) with a few shops. If Bangalore’s civic authorities could realize the gold mine that they are sitting on, they could invite developers to buy large chunks of land from the current owners and then build dense and diverse developments that provide avenues for employment and apartments to reside. That would eliminate a considerable chunk of today’s traffic that has to travel between Sirsi Circle and Agara Junction. The biggest infill project that India wanted to undertake but got stalled in the wake of the 2008 financial market meltdown was the Dharavi Slum redevelopment project in Mumbai. Fortunately, the project has only been delay not scrapped.
Although India has not seen scientific initiatives to develop models that quantify the benefits of mixed-use developments, there appears to circumstantial evidence to back the 5-D theory’s applicability in India or anywhere else in the world. In the good old days that our parents & grandparents reminisce about, our cities were much denser with a lot of avenues available within short walking distances. That coupled with lack of motorized modes of transport resulted in lower congestion than what we experience today. A report published the Ministry of Urban Development in 2008, provides change in trip lengths over the years (See Page 96).
The average trip length for a city with a population of 40 to 80 lakhs in 1991 was between 6.4 & 7.62 kilometers. The average trip for a city with a population of more than 80 lakhs in 2007 was 9.6 to 11.9 kilometers. Bangalore meets these population ranges for the 1991 and 2007 trip length estimates. This indicates that the average trip length for a city like Bangalore increases by a minimum of 2.4 kilometers (or 33%) and a maximum of 5.5 kilometers (or 86%). It is hard to imagine anyone challenging the fact that an average Indian’s trip length has increased considerably over the years, pointing to urban sprawl, something that can be avoided.
It’s not that the Government of India is not aware of it. It is. The Ministry of Urban Development has formulated a National Urban Transport Policy, Unfortunately, the policy is designed in such a way that planners who follow it will only be chasing the urban sprawl rather than preventing it. The policy document acknowledges the challenges posed by urban sprawl and its impact on non-motorized modes of transport, but provides no encouragement/guidance to prevent it.
Indian planners should learn from their western counterparts. Instead of repeating their follies, India should leverage its development pattern as it exists today and transform it to build world class self-sustainable communities within its cities. Highways are essential, so are signal-free corridors but we must know where to draw the line and grow smart.
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