DEVELOPING BUS RAPID TRANSIT SYSTEM IN INDIA MADHURI JAIN Research Scholar Faculty of Science D.E.I, Dayalbagh. Agra India madhulikajain32@yahoo.com ARTI SAXENA Womens Polytechnique Dayalbagh, Agra India artisaxenadayalbagh@yahoo.com PREETVANTI SINGH Faculty of Science D.E.I, Dayalbagh, Agra India preetvantisingh@yahoo.co P.K. SAXENA Faculty of Engg. D.E.I, Dayalbagh, Agra India premkumarsaxena@yahoo.co.in Corresponding Author Madhuri Jain 71, Yamuna Vihar Phase II Karamyogi Enclave Kamlanagar Agra 282005

ABSTRACT Urban transport is a nightmare in India though most urban residents take it as a fait accompli. Indian cities, of all sizes, face a crisis of urban transport. Despite investments in road infrastructure, and plans for land use and transport development, all cities face the ever increasing problems of congestion, traffic accidents, air, and noise pollution. Bus Rapid Transit (BRT) is growing in popularity throughout the world. The reasons is its passenger and developer attractiveness, its high performance and quality, and its ability to be built quickly, incrementally, and economically. BRT also provides sufficient transport capacity to meet demands even in the largest metropolitan regions. This paper summarizes key trends transport system and travel behavior of India , and the issues to be considered for the development of BRTS to mitigate Indian transportation crisis. Keywords: Transportation system, Transportation Problems, BRTS Introduction India is the 2nd largest country in the world, measured by population and arable land and is expected to become the 3rd largest economy in the world by 2025, just behind US and China. In terms of growth it is the second fastest growing major economy in the world. Transportation in India is a large and varied sector of the economy. The share of Indian transportation investments in total public investment declined during the period from the early 1950s to the early 1980s; real public transportation investment also declined during much of that period because of the need for funds in the rest of the economy. Zhang et al [10] developed a modal split model maximizing spatial welfare and constrained by travel money budget and time budget. This approach was different from the general econometric -based approach used in most existing macro transport studies and deal with the cost and speed of transport modes as important variables explicitly. Patnaik et al [6] developed a set of regression models that estimated arrival times for buses traveling between two points along a route. The data applied for developing the proposed model were collected by Automatic Passenger Counters installed on buses operated by a transit agency in the northeast region of the United States. Baltes [2] presented a statistical analysis of the data from two on-board customer surveys conducted in 2001 of the BRT Systems in Miami and Orlando, Florida. Yedla and Shrestha [9] examined the impact of BRTS including various qualitative criteria for the selection of alternative transportation options in Delhi. Singh [8] provided a reliable data set of land-based passenger traffic volumes in India, estimated the long-term trends in motorized traffic volume and modal split and also estimated the level and growth of energy demand and CO2 emission from the passenger transport sector.

Badami and Haider [1] explored the factors that contribute to and affect efforts to improve this situation, based on an analysis of the financial and operational performance of the public bus transit service in the four metropolitan centres and four secondary cities during the 1990s. Kathuria [3] investigated whether the enactment of policy instruments and the efforts have led to commensurate fall in air pollution in Delhi. The analysis showed that the imposition had not resulted in concomitant improvement in ambient air quality. Rabl [7] presented a life cycle assessment comparing diesel buses with buses fueled by natural gas. The data for the emission of pollutants were based on the MEET Project of the European Commission (EC), supplemented by data measured for diesel and gas buses in Paris. Mukherjee et al [5] studied work exposure of drivers and conductors of special state buses in Kolkata, India to noise, heat, respirable dust and volatile organic compounds (VOCs). Equivalent noise exposures of drivers at work and in-bus noise were evaluated using a precision noise level meter. Mohan and Tiwari [ 4] discussed the issues concerning public transport, safety and the environment and illustrated that unless the needs of non-motorised modes of traffic are met it would be almost impossible to design any sustainable transportation system for urban areas.

Indian cities face transport crisis characterized by levels of congestion, noise, pollution, traffic fatalities and injuries, and inequity far exceeding those in most European and North American cities. Indias transport crisis has been exacerbated by the extremely rapid growth of Indias largest cities in a context of low incomes, limited and outdated transport infrastructure, rampant suburban sprawl, sharply rising motor vehicle ownership and use, deteriorating bus services, a wide range of motorized and non-motorized transport modes sharing roadways, and inadequate as well as uncoordinated land use and transport planning. This paper summarizes key trends of transport system and travel behavior of India , and the issues to be considered for the development of BRTS to mitigate Indian transportation crisis. Urban transport problems of India 1. Population Growth The most important factor common to India is population growth. The total urban population of India burgeoned over the past three decades, rising from 109 million in 1971 to 160 million in 1981 (C47%), 217 million in 1991 (C36%), and 285 million in 2001 (C31%) (Office of the Registrar General of India). Urban population of India is growing at an average rate of around 3 percent per annum (Figure 1). Assuming a decadal increase of around 37%, Indias urban population is expected to be around 540 million during 2021. In terms of percentage of total population, the urban population has gone up from 17% in 1951 to 29% in 2001 and is expected to increase up to around 37% by the year 2021 (Figure 2). Consequently, the number and size of cities have also increased considerably.

Figure 1: Population of India

Figure 2: Share of Urban Population in India

During the 1990s, 68 million people joined the ranks of urban dwellers which implies a slower decadal growth of 31 percent when compared to the growth of 36 percent during the 1980s. Although urbanization has slowed down in India during the 1990s, the number of metropolitan cities those with a million plus population has increased over this period. From 23 in 1991, the number of metropolitan cities rose to 35 according to the Census of India, 2001. The trends indicate the continued urbanization and metropolitaniztion in the years to come. 2. Vehicular Growth and Modal Split During the year 2000, more than 6.2 million vehicles were plying in mega cities (Mumbai, Delhi, Kolkata, and Chennai) alone, which constitute more than 12.7 percent of all motor vehicles in the country (Table 1). Delhi, which contains 1.4 percent of the Indian population, accounts for nearly 7 percent of all motor vehicles in India. Table 1: Total Number of Registered Motor Vehicles in selected Metropolitan Cities of India (in

thousands) Metropolitan Cities

1995 1996 1997 1998 1999 2000

Pune 358 412 468 527 568 593 Mumbai 667 724 797 860 911 970 Kolkata 561 588 588 664 Not Ava. Not Ava. Hyderabad 557 764 769 887 951 Not Ava. Chennai 768 812 890 975 1056 1150 Bangalore 796 900 972 1130 1332 1550 Ahmedabad 510 572 631 686 739 799 Source: Motor Transport Statistics of India There are no reliable time-trend data on modal split distributions, but the statistics on vehicle fleet sizes in Figure 3 shows the extremely rapid growth of motorcycle ownership, and private car ownership. This has resulted in increasingly congested roadways that slow down buses, increase bus operating costs, and further discourage public transport use. In figure others includes tractors, trailers, motorized three-wheelers (passenger vehicles) such as auto rickshaws etc.

Figure 3: Growth of Indias motor vehicle fleet by type of vehicle

Source: Ministry of Road Transport and Highways

3. Limited Road Network Road transport is the dominant mode of transport in the country, and plays a big role in trade and tourism. The road network is a patchwork reflecting the cities development along national roads and railways, well before the advent of individual motor vehicles. The network between the high-density corridors is poorly developed, since in -fill construction has often been done illegally. While demand for road transport has increased rapidly, infrastructure has not kept pace leading to serious network deficiencies. Inefficient systems of construction coupled with poor maintenance have resulted in poor road infrastructure. The situation is further exacerbated by unimaginative design of roads that do not allow segregation of vehicles traveling at vastly different speeds. Mobility is thus restricted to the speed of the slowest vehicle. 4. Traffic injuries and fatalities Traffic crashes in Indian cities pose a severe public health problem, resulting each year in about 80,000 deaths, 1.2 million serious injuries (requiring hospital visits), and 5.6 million minor injuries. A large number of deaths in the country are due to road accidents. The heterogeneity and magnitude of vehicle population, the unpredictability of human behavior, poor road geometry, deficiencies in vehicle and road design, and economic constraints are some of the factors leading to road accidents. As shown in Table 2, the number of traffic fatalities has increased more than 5-fold since 1971. Even controlling for population growth in India, the traffic fatality rate per million inhabitants has tripled over the past three decades, so that the average Indian is now over three times as likely to be killed in a traffic accident. Fatalities, in particular, increase with rising motor vehicle use, since the likelihood of fatal injuries increases sharply with speed. Aside from the increase in motor vehicle ownership and use, several other factors contribute to the safety problem: inadequate road supply and quality, often unpaved and in bad repair; unsafe driving behaviorwhich results from virtually non-existent driver training, extremely lax

licensing procedures, and lack of traffic law enforcement; unsafe vehicles; inadequate or non-existent traffic signals and signage and lack of traffic management;

forced sharing of narrow, crowded rights of way by both motorized, non-motorized vehicles, pedestrians, animals, and street vendors;

overcrowding of buses, auto-rickshaws, and even motorcycles. Table 2: Number of vehicles, population and road traffic fatalities in India

Source: Ministry of Road Transport and Highways (2003).

4. Lack of Parking Place Daily trips made by personalized modes require parking spaces at both ends of the trip. There is a huge gap in the demand and supply of parking spaces which leads to spill over of parking on the road. There is lack of proper planning and management of parking facilities. Inadequate and inefficient public transport systems lead to greater use of private modes of transport. A car is parked for 90 to 95% of time at residence or place of work. Land resources in the metropolitan cities are limited and scarce, while the increase in parking demand is high. Inadequate parking adds to congestion and delays on major arterial roads. 5. Traffic Congestion Traffic congestion is probably the most visible, most pervasive, and most immediate transport problem plaguing Indias metropolitan cities on a daily basis. It affects all modes of transportation and all socioeconomic groups. Most estimates as well as anecdotal impressions suggest rapidly worsening congestion. For example, average roadway speeds for motor vehicles in Mumbai fell by half from 1962 to 1993, from 38 km/h to only 1520 km/h. In Delhi, the average vehicular speed fell from 2027 km/h in 1997 to only 15 km/h in 2002. Moreover, the periods of peak congestion in Delhi now last 5 hours from 8:30 to 10:30 in the morning and from 4:30 to 7:30 in the evening. In Chennai, average speed is 13 km/h, and in Kolkata it ranges from 10 to 15 km/h overall but falls to only 7 km/h in the center (Times of India, 2003). Traffic congestion is frustrating and time consuming for travelers. With most Indian metropolitan cities sprawling outward to the periphery, average trip distances have been increasing. Combined with the slower travel speeds, suburban sprawl has greatly increased average travel time, which now amounts to 2 or 3 hrs a day for the trip to and from work. The stop-and-go traffic flow caused by congestion also wastes energy and increases pollution. Congestion within vehicles unquestionably impairs safety, with some passengers falling off overcrowded vehicles, since many are forced to ride on the roofs or hang onto the sides of vehicles that often have no shutters for the doors and windows. Perhaps the most obvious

cause of congestion is the rapid increase in travel demand, especially of motorized travel, compared to the very slow growth in transport infrastructure. 6. Pollution Noise, air, and water pollution are all serious problems in Indian cities, and transport sources contribute to all three kinds. The most comprehensive statistics are shown in Table 3 for air pollution. Most prominent among them is the high level of air pollution caused by motor vehicles. Suspended Particulate Matter (SPM) levels in the six major metropolises is well above the National Ambient Air Quality Standards. Nitrogen oxides and Sulphur dioxide are currently within limits but could cross acceptable levels unless kept under control.

Table 3: Air Pollution in Indian cities SO2 (gm/cu.m) NO2 (gm/cu.m) SPM (gm/cu.m) City 1993 1998 2003 1993 1998 2003 1993 1998 2003 Delhi 13.70 15.60 12.20 30.10 35.10 43.30 362 342 315 Kolkata 65.10 47.20 18.0 62.00 39.70 75.50 507 283 244 Mumbai 49.50 15.90 7.70 32.30 14.70 18.70 475 211 219 Bangalore - 41.60 10.80 - 28.40 44.90 - 239 198 Hyderabad 7.30 7.60 9.70 11.00 22.10 19.50 156 152 139 National Ambient Air quality Std

60 60 140

Source: Central Pollution Control Board (http://www.cpcb.nic.in) In Figure 4, levels of air pollution concentrations are highest for suspended particulate matter (SPM) and respirable suspended particulate matter (RSPM), which exceed World Health Organization air quality standards, as well as offic ial Indian government standards, for all of the cities shown (Ministry of Petroleum and Natural Gas, 2002). Indeed, for Indias three largest cities, SPM and RSPM levels are three to four times higher than the WHOs maximum acceptable levels, and among the highest in the world, indicating a very severe health hazard (World Health Organization, 2000). While levels of CO, NOx, and Sox are generally considered moderate to low in most Indian cities, ozone levels have been increasing in virtually all Indian cities, causing a range of respiratory illnesses and irritation. Figure 4 Air Pollution Levels in Indian Cities Source: Ministry of Petroleum and Natural Gas, 2002

7. Need for an Urban Transport Policy Urban transportation is the single most important component instrumental in shaping urban development and urban living. While urban areas may be viewed as engines of growth, urban transport is, figuratively and literally, the wheel of that engine. In fact, the efficiency of cities greatly depends on the development of transport systems, as urban transport is a catalyst for overall development. However, the cities in India suffer from the absence of a cogent urban transport policy. Urban transportation problems in India are manifest in the form of congestion, delay, accidents, energy wastage, and pollution. The need of the hour is therefore a sound urban transport policy. The major thrust of such an urban transport policy should include integrated planning, an optimum share between public and private modes, the choice of relevant technology for public transport systems, optimal use and management of available resources, restructuring of monetary and fiscal policy to encourage and promote public transport, and establishment of institutional arrangements, at all levels of governance, particularly at the city level, for planning, development, operation, management, and coordination of urban transport systems. 8. Institutions India has more fragmented institutional network for urban transport like Bangalore Metropolitan Transport Corporation (BMTC), Chennai Metropolitan Transport Corporation (CMTC), Delhi Transport Corporation (DTC) etc. Chennai Metropolitan Transport Corporation (CMTC) was created in 1972, under Companies Act of 1956, in a wave of nationalization of the then private operators, whose performance had become unacceptable. It is owned by the State of Tamil Nadu. CMTC operates conventional, scheduled bus services, with a staff of about 18,000 and a fleet of about 2,780 buses in peak services. Bangalore has a more fragmented institutional network like Bangalore Municipal Corporation (BMC), Bangalore City Traffic Police, and Bangalore Development Authority (BDA) for urban transport. The DTC provides 10% of the total public transport in Delhi. It has about 800 buses plying on interstate routes and 2,200 CNG buses for city operations. The repair and maintenance wing has two central workshops. But there is a pressing need to strengthen institutions in the transport sector. Often the institutions responsible for urban transport generally lack the executive, financial, and technical skills to cope with existing situations, let alone emerging transport problems. Central government should provide training and technical assistance to local governments to prepare and implement sound policies and programs. Vast improvements are needed in Indias public transport systems, but the necessary funding is not available. Most buses and trains in Indian cities are old and poorly designed, inadequately maintained, dangerously overcrowded, undependable, and slow. Transportation demands in urban areas continue to increase rapidly as a result of both population growth and changes in travel patterns. In the era of environment concerns and limited space available in cities, transport planners have to provide a system, which can ensure safe and clean mobility. This requires planning a system, which is affordable, reliable and efficient from the user as well as operators perspectives. A road based Bus Rapid Transit system (BRTS) offers an opportunity for creating a system capable of meeting multiple needs of users and operators. Bus Rapid Transit (BRT) takes part of its name from "Rapid Transit", which describes a high-capacity transport system with its own right-of-way, implemented using buses through infrastructural and scheduling improvements, to provide a high level of service. Bus rapid transit (BRT) is a flexible, high performance rapid transit mode that combines facilities, equipment, service and intelligent transportation system (ITS) elements into a permanently integrated system with a quality image and unique identity. Bus Rapid Transit System (BRTS) BRTS is a flexible mode that integrates capital and operational improvements to create a faster, higher-quality mode of travel than conventional bus service. It is a permanently integrated system of facilities, services, and amenities that collectively improve the speed, reliability, and identity of bus transit. Figure 5 shows some characteristics of BRT system as running in developed Countries. In many respects, BRT is

rubber-tired light rail transit (LRT), but with greater operating flexibility and potentially lower capital and operating costs.

Figure 5: Some Characteristic s of BRTS BRT is an appropriate choice for many corridors because it: 1. Protects rights-of-way 2. Utilizes existing resources 3. Acts as a pathfinder 4. Garners political/community support 5. Cost effective means of transportation 6. Reliably operate at high speed 7. Integrated into urban environment. Protects Rights-Of-Way: The rate of growth in travel demand is exceeding the rate at which road space can be made available. Facilities designed to accommodate 20 to 30 years of traffic growth are reaching saturation well before their time. Within the confines of the existing right-of-way, it is difficult for transit to provide any improvement, as transit vehicles are subject to the same traffic conditions as other modes. The only solution is to retrofit exclusive transit facilities, which requires the commandeering of existing travel lanes or the acquisition of additional rights-of-way. Utilizes Existing Resources: To maintain stability within the transit operating authority, it is important to utilize available resources to their full extent and build on the strengths of the organization rather than disregard present structures and introduce an all-new system. The BRT system, therefore, allows the operating authority to consume the assets (i.e., get the most use out of them) while positioning itself for more advanced modes/operating systems.

Acting as a Pathfinder: BRT systems, allow operators to validate passenger demand for a higher level of service, thus reducing the risk of service failure. BRT provides an opportunity to partly replicate service and operational characteristics of a higher mode. If prerequisite thresholds of demand for the higher mode are developed, then its introduction will be better assured of success. Garnering Political/Community Support: BRT provides the opportunity to develop a high-quality mass transit system in a stepwise, incremental manner. Lower-cost investments can be made in the system accordingly. Time should be allowed for the benefits of the improvement to accrue and rider ship to respond. From a community standpoint, this is a fiscally responsible approach. The BRT system is seen as a logical step forwardby enhancing what is already in existence, without overextending the financial means of the community. Seeing the benefits of BRT, the BRT system should be developed with following features: 1. Bus specifications BRT vehicles should be designed to meet the functional requirements of the BRT systems. The BRT system should endeavor to develop a unique identity whereby the look of its vehicles supports the overall image of the operation. To assist the mobility impaired - Carefully consider platform connection (bus-mounted bridge: yes or no?) - Space with fastening device for at least one wheelchair per bus - Lifts where there is no level boarding (i.e. feeder buses) - Signs reserving seats for pregnant women, the elderly and infirm To assist the sight impaired - Contrasting color schemes for stanchions, holding bars, doors - Consider public address system to announce next station - Specify good inside lighting To assist the hearing impaired - Specify lit signs to indicate next station - Coordinate physical and operational planning of BRT Bus entrances and interior design Mixed (trunk and local services) High-floor conventional - Sao Paulo Low-floor manual ramps in Santiago High (left door) and step-down (right door) Color coded buses and stations Feeder bus entrances Minimize vertical distance Handrail to ease exiting Retractable step (or kneeler feature) No turnstiles ins ide bus Multiple door boarding and alighting Interior bus design Non-skid flooring Priority seating

Wheelchair securement Higher capacity bus Stop request signals Stanchions in contrasting colors Public Space Sidewalks and Paths Intersections and Crossings Signalization Pedestrian Grade Separations Pedestrian Access Roads 2. Feeder line deployment and wheelchair access

Accessible feeder buses on one route at a time Low-floor buses Wheelchair assistance Personal assistance Wayside platforms

3. Trunk Line Stations

Gentle ramps to stations Station entrances and exits Good lighting Station Assistants Uniform station design

Seats and Supports Sliding Doors Visual Elements Audible Elements Tactile Elements Features at Terminals

Added Information Elevators in exceptional situations

4. The platform-bus gap With bus-mounted bridges

Additional cost: $3,000 per bus (Quito) Additional time for automatic deployment of bridge: 5 sec. per station (Quito)

Without bus-mounted bridges Examples: BRTS in Colombia, Mexico Maximum permissible gap: 10 cm Careful bus docking at stations Front-door entry for wheelchairs

Importance of station assistants 5. Access to feeder line bus stops

Prioritizing selected bus stops Designate formal stops Bogot Identify stops with highest passenger volumes Select those that have accessible links with neighborhood

Bus stop access features

Paved platform New Delhi Shelter where possible Seats or ischiatic supports Good lighting

6. Signage and announcements Outside bus Large bus route and destinations signs Signs in front and at entrance doors Contrasting colors and illumination at night Announcements of bus destination Inside bus Readable maps of system or route Electronic visual displays of next stop Audible announcements of next stop Audible warnings of door opening/closing Signs and color schemes to identify priority seating 7. Public Participation Focus Groups 6-12 participants Persons with physical, sensory and cognitive impairments Also: Pregnant women, seniors See: TRL Overseas Road Note 21 Create Advisory Committee Meet periodically with Government planners Ensure that inclusive transport is put on the agenda Prioritize actions Avoid costly mistakes Monitor results 8. Fare Collection

Single flat fare Fare cards Fare card vending sites Fare cards for passengers with special needs At least one turnstile appropriate for wheelchairs Off vehicle fare payment Pre paid fare

9. Public information and training System information

Route and system maps Tariff structure and special fares Accessible service center Accessible website (example: Santiago)

10. Operation of buses simple route structure, frequent service at all times of day,

headway-based as opposed to time-point schedules, less frequent stops, exclusive lanes, Direct routing

Simple, easy-to-understand route structures with termini at major generators. Special training module for bus drivers, raising their awareness of the constraints faced by disabled

passengers Keep buses clean and well-lit Service concessions must specify criteria of driving behavior (acceleration, breaking, curves) Simple route structure 11. Planning feeder bus network, and coordinated land-use planning. Priority at intersections

Queue jumpers and other transit priority measures at intersections can reduce transit travel time. Signal priority

BRT buses would receive preferential treatment at signalized intersections to reduce travel time. Limited stations

Station spacing is lengthened to reduce travel time. Improved passenger boarding facilities

BRT stations should have permanence and substance. Stations should also be integrated into commercial developments and neighborhoods wherever possible.

Coordination with land-use planning BRT system design and land-use planning should be coordinated to provide high-quality transit

service in proximity of high-intensity land uses. Level boarding

Designing the passenger boarding area at the same height as the bus reduces dwell time at stations and provides easy access for all users.

12. Public education Teach passengers to be considerate Explain needs of persons with disabilities 13. Considerations for inclusive BRT design Investment and operating costs

must be kept low extra infrastructure costs paid by ( financially constrained) Government extra bus costs are ultimately paid by ( generally poor) passengers

Many aspects of inclusive design do not cost more Color schemes of stops and buses Clear signage Space for wheelchair passage Often: ramps instead of steps

Many are important for safety, security and image At stops and terminals: illumination, benches, cleanliness, assistants In bus: illumination, driving manner, seats for infirm (considerate behavior) Walking to bus stop: raised crosswalks, sidewalk ramps, illumination Improved enforcement reduces crime and sense of vulnerability

Conclusion As the population continues to grow, the demand for motorized vehicles will increase as well. The increasing number of vehicles on the road will emit thousands of tons of pollutants into the atmosphere each year, affecting not only the city, but the entire globe. India has implemented numerous policies regarding vehicular emissions, but these have had little, if any, affect on the quality of the air. This requires planning a system, which is affordable, reliable and efficient from the user as well as operators perspectives. A Bus Rapid Transit System offers an opportunity for creating a system capable of meeting multiple needs of users and operators which combines facilities, equipment, service and intelligent transportation system (ITS) elements into a permanently integrated system with a quality image and unique identity.

References 1. Badami M.G. and Haider M., (2007), An analysis of public bus transit performance in Indian cities,

Transportation Research Part A: Policy and Practice, 41(10), 961-981. 2. Baltes M.R., (2003), The Importance Customers Place on Specific Service Elements of Bus Rapid

Transit, Journal of Public Transportation, 6(4), 1-19. 3. Kathuria V., (2002), Vehicular pollution control in Delhi, Transportation Research Part D, 7, 373

387. 4. Mohan D. and Tiwari G., (1999), Sustainable Transport Systems Linkages between Environmental

Issues, Public Transport, Non-Motorized Transport and Safety, Economic and Political Weekly, XXXIV (25), 1580-1596.

5. Mukherjee A.K., Bhattacharya S.K., Ahmed S., Roy S.K., Roychowdhury A. and Sen S., (2003), Exposure of drivers and conductors to noise, heat, dust and volatile organic compounds in the state transport special buses of Kolkata city, Transportation Research Part D, 8, 1119.

6. Patnaik J., Chien S., and Bladikas A., (2004), Estimation of Bus Arrival Times Using APC Data, Journal of Public Transportation, 7(1), 1-20.

7. Rabl A., (2002), Environmental benefits of natural gas for buses, Transportation Research Part D, 7, 391405.

8. Singh S.K., (2006), Future mobility in India: Implications for energy demand and CO2 emission, Transport Policy, 13(5), 398-412.

9. Yedla S. and Shrestha R.M., (2003), Multi-criteria approach for the selection of alternative options for environmentally sustainable transport system in Delhi, Transportation Research Part A: Policy and Practice, 37(8), 717-729.

10. Zhang S., Jiang K. and Liu D., (2007), Passenger transport modal split based on budgets and implication for energy consumption: Approach and application in China, Energy Policy, 35(9), 4434-4443.