New Delhi, Jun 24 (PTI) Factoring in traffic congestion and environmental degradation in Delhi, researchers have pitched for exploring a sustainable multimodal transport system with high accessibility and said with greater access to the metro network, people would prefer it as the "main mode" for travel via MMTS.The researchers in a study titled "GIS and Gravity Model-Based Accessibility Measure for Delhi Metro", published recently in a foreign journal, have also claimed that the implementation of the phase-IV project of the Delhi Metro "could reduce the average travel time between zones and metro stations".The study was carried out at three different levels -- the measure of accessibility, the policy for accessibility and the relation of accessibility with MMTS.MMTS explores the coordinated use of two or more modes of transport for safer, faster and more comfortable movement of passengers in urban areas."Traffic congestion and environmental condition of Delhi are degrading continuously, and to improve the situation, a sustainable Multi Modal Transport System (MMTS) with high accessibility must be explored," the study said.Due to an increasing population and migration of people from nearby places to Delhi for work, education and business, the city roads and the environmental condition are becoming worse. To improve accessibility, it is required to make a policy revolving around accessibility, it said.The paper, authored by two researchers from the Central Road Research Institute (CRRI), CSIR and NIT-Surathkal, also discusses the policy that "accessibility will be improved by expanding the metro network and by making metro available in walkable distance"."With the improvement in accessibility through metro, air and noise pollution will reduce due to a reduced congestion on roads as commuters will prefer MMTS," it said.The research paper said "with the higher level of metro accessibility, people will prefer the multimodal transport system with metro as the main mode"."From these results of the study, we can conclude that the use of policy for accessibility for planning a city like Delhi will help in the development of the city in a sustainable manner," it added.Under the approved segment of the ongoing phase-IV project, 65 km of new metro lines shall be constructed across three different corridors comprising 45 stations. These new sections shall provide inter-connectivity among the already operational lines of the Delhi Metro.According to the government, the Mukundpur-Maujpur, R K Ashram-Janakpuri West and Aerocity-Tughlakabad corridors were approved by the Cabinet.The work on phase-IV had begun in December 2019 with a groundbreaking ceremony, but was hit after the outbreak of COVID-19 in Delhi in March 2020.In the paper, a "policy to improve zone-to-zone metro accessibility for work purpose is discussed and the relation between multimodal transport system with accessibility" was studied, using software models.It was observed that by additions and extensions of metro lines, transport accessibility is greatly improved.The study also shows that the "percentage of zones in Delhi with higher accessibility level could increase from 5 to 13.88 with the implementation of phase-IV of metro".In addition, the implementation of phase-IV could reduce the average travel time between the zones and metro stations. It will also reduce the travel time between the metro stations substantially (for the zones covered in the study, the average travel time is reduced by 23.63 per cent and for the stations, it is reduced by 17.73 per cent), it said.Besides, the study can be extended by using the metro fares as a parameter. "Delhi metro fare is high and it will be higher after the execution of phase-IV metro plan. This might restrict the lower income group and students to prefer metro," it said.Also, the availability of metro in a walkable distance and a safe environment for pedestrians are also needed to improve metro accessibility, the researchers said. PTI KND RC