In this rail system, the underground railways are generally provided at a depth of more than 25 m. The railway line is constructed in a tunnel that is circular or tubular. The main reason for taking the railway so deep into the ground is to avoid it interfering with the water supply mains, sewerage system, telephone lines, gas lines, etc., which are normally located within 10 m of the natural ground. Some of the salient features of the tube railway are given below.
(a) The railway stations of the tube railway are generally cylindrical in shape.
(b) Only electric traction is used for hauling trains in order to avoid smoke and the resulting environmental pollution.
(c) For the convenience of passengers, escalators are provided for accessing and existing the stations.
(d) An automatic signal is provided for the faster and effective movement of trains. The trains stop automatically when the signal indicates impending danger. Human error is thus avoided to the maximum possible extent.
(e) In order to ensure the safety of passengers, it is essential that the doors of the compartments are closed before the train can start. This is done by means of a centrally operated switch installed in the driver's cabin.
(f) Automatic ticket issuing machines are installed in the concourse in order to reduce the need for manpower and to ascertain that tickets are issued speedily for the convenience of passengers.
(g) Adequate indication and warning boards are displayed at significant locations so that the passengers have ready information regarding the timing of the trains and the platform number for each train without making too many enquiries.
Superiority of rail transport over road transport
Rail transport is becoming increasingly popular all over the world as far as its relation to urban transport is concerned. This is due to the following advantages that rail transport has over a road transport system.
(a) Its passenger carrying capacity per lane space is 10 times more than that of road transport.
(b) It is less prone to accidents and, therefore, the loss of life is less as against the frequent road accidents due to acute congestion on the roads that take a heavy toll on life.
(c) It has an inherent advantage in respect of reduced levels of air, noise, and other forms of environmental pollution. It is free from smoke and dust, which cause serious health problems.
(d) It ensures energy conservation, as it is run on electricity, whereas road vehicles depend on oil the world reserves of which are fast running out.
(e) It is cheaper than road transport. The subsidy required for rail transport per kilometre is less than that required for road transport.
Study of MRTS
It has been experienced the world over that road transport alone cannot efficiently meet the needs of intra-urban transport in the case of large cities. Rail-based mass transport has been found necessary for keeping road congestion within acceptable limits. The need for a rail-based mass rapid transport system for the four metropolitan cities of India, namely, Delhi, Kolkata, Mumbai, and Chennai, was recognized in the early 1970s. Accordingly, the Planning Commission set up MRTS study teams for each of the four cities under the guidance of the Ministry of Railways. The study reports were finalized in the mid-1970s. On account of the massive investments that were required and the simultaneous paucity of funds, the project remained on paper except for a corridor in Kolkata, which was taken up subsequently. For various reasons, progress on the Kolkata project was slow and was commercially operated for the first time in October 1984.