TOKYO Metro is the oldest system in Asia, with the Ginza Line opening in 1927. It comprises nine lines totalling 195.1km carrying 6.84 million passengers a day, with seven lines providing through operation to other railways. Tokyo Metropolitan Bureau of Transportation (Toei) also operates four metro lines with a combined length of 109.1km, which carry another 2.4 million passengers a day. The entire rail system in Tokyo covers 532.6km, making it one of the largest urban rail networks in the world, and accounting for 70% of all transport in the Tokyo area.

A major expansion of through operation was achieved in March 2013 when reciprocal service was introduced between Fukutoshin Line and two other railways: the Tokyu Toyoko and Yokohama Express Minatomirai lines. With through operation already established with the Tobu Tojo and Seibu Ikebukuro lines in conjunction with another metro line - the Yurakucho Line, the Fukutoshin Line forms the backbone of an extensive network covering western Tokyo and Yokohama.

TokyoThe 2013-2015 three-year plan has seven priority measures within three so-called pillars, as Mr Yoshimitsu Oku, Tokyo Metro's president explains: "The first pillar is providing greater peace of mind. Believing that peace of mind is the sum of safety and service, we pursue ways to ensure and enhance safety, especially preparedness for natural disasters, along with offering high-quality, customer-oriented services.

"The second pillar is growing in step with Tokyo. In this regard, we are working alongside local communities and our reciprocal through-service rail company partners on initiatives to further boost the attractiveness and value of areas neighbouring our lines.

"The third pillar is exploring new possibilities. We are leveraging our expertise in subway construction, operations and maintenance accumulated over 86 years to expand into overseas markets." Tokyo Metro is helping to set up an organisation to operate the new Hanoi metro in Vietnam. "We are also aggressively pursuing research and development in a host of fields, including emergency responses and enhancing the reliability of tunnels and equipment," Oku continued.

The Yen 50bn ($US 404m) renovation of the 14.3km Ginza Line is the biggest project currently underway as part of the first pillar. This is one of only two standard-gauge metro lines on the Tokyo Metro network, the other being the Marunouchi Line, and the reason why these two lines do not have though running onto other railways, most of which are 1067mm gauge. The Ginza Line also has a small profile, and third rail electrification in common with the Marunouchi Line.

Work on renovating the Ginza Line started in 2012 and will not be completed until 2020. The line has already been resignalled and track relaying is underway, with the work carried out at night to avoid any disruption to services. The first of a fleet of 39 six-car series 1000 trains entered service in April 2012 and delivery of the entire fleet should be completed by March 2017.

Another important project entails what Tokyo Metro describes as "sweeping measures" to reduce congestion and prevent delays on the 30.8km Tozai Line which will involve a major upgrade of this east-west line.

For the first time, Tokyo Metro has decided to introduce a common train design with one of the railways with which it has through running. The trains will start to enter service on the Hibiya Line and Tobu Railway next year, with completion scheduled for 2019.

The existing fleet comprises eight-car trains formed of 18m-long vehicles, but by having 20m-long cars it will be possible to operate seven-car trains with the new fleet which will reduce costs while maintaining capacity. This will be a large order as there are currently 42 Hibiya Line trains and 24 Tobu Railway sets.

The new trains will have standard specifications for major equipment and the car body. They will be powered by permanent magnet synchronous traction motors, and equipped with the VVVF inverter control currently used on Tokyo Metro series 03 trains.

The internal layout will also be standardised. The trains will have 460mm-wide seats compared with 450mm on Tobu series 20,000 trains and 430mm on series 03 metro trains. Information displays with 17-inch LCD screens will be fitted above the doors to help guide passengers through their journey.

The Hibiya Line is infamous for a serious accident which occurred in March 2000 when a train derailed on a 160m-radius curve and struck an on-coming train, killing five people and injuring many more. The accident was caused by a weight imbalance of wheels on a bogie which ran over rails which had just been ground, and the metro did not have anti-derailment rail guards on sharp curves at that time. Since then equipment has been installed at depots to measure wheel weight, and the shape of the wheel tread has been altered.

Other than this, Tokyo Metro is proud of its safety record. During the disastrous Sendai earthquake in 2013, services were only halted for six hours. The network was pronounced safe to operate after only three hours. However, it was decided not to resume operation for another three hours to allow people time to recover after the initial shock.

Earthquake protection

Tokyo Metro has done a lot of work to prevent earthquake damage by strengthening viaduct and tunnel supports, and taking steps to prevent bridges and viaducts from collapsing. Further work is planned on viaduct pillars and to reinforce masonry retaining walls.

Seismographs are installed at six locations on the metro which are connected to the main control centre enabling train operations to either be restricted or halted entirely depending on the severity of the earthquake. Tokyo Metro also uses an early seismic alert system based on earthquake warnings issued by the Japan Meteorological Agency. Inspections are then carried out using information gathered from seismographs at a further 36 locations so that train operation can resume in areas confirmed safe. Tokyo Metro has an emergency broadcasting system, together with smoke and fire control equipment.

Flood barriers have been installed at deep-level stations where there is a risk of flooding. Flood gates have also been fitted in running tunnels at five critical locations and another four are planned.

To improve safety, half-height electrically-operated platform-screen doors have been fitted on five lines and 47% of stations are now equipped. Although their installation has increased station dwell time by a few seconds, the introduction of platform-screen doors has enabled the elimination of train guards. The Hibiya and Chiyoda lines will be the next to be equipped.

Only the 21.3km Namboku Line has full-height platform-screen doors as it was originally intended to operate this line without drivers. However, the plan to introduce driverless operation was dropped when it was decided to have through running with the Saitama Railway, which opened in March 2001. There is also a 2.3km common section with Toei's Mita Line.

Tokyo Metro is trying to achieve barrier-free access to trains at stations. By March last year, 313 lifts had been installed at 153 stations, or 80% of stations on the network. In addition, 130 stations have disabled toilets. It is planned to make more stations barrier-free in time for the 2020 Olympic Games, which will be held in Tokyo.

Improving service

To improve service to passengers, service staff have been introduced at 14 major stations including Ueno to assist passengers with ticket purchases and provide directions. Passenger information is provided in four languages, while staff at information desks speak English. Tokyo Metro carries 13 million foreign passengers a year and this number is expected to jump to 20 million during the Olympic Games. The metro's toll-free customer relation centre receives 100,000 telephone calls or suggestions on how to improve services each year.

Four metro lines are already equipped with automatic train operation but still retain drivers. However, a project has recently been launched to study the introduction of fully automatic driverless operation. Plans are also being drawn up for a new control centre to replace the existing integrated control centre.

Last month Tokyo Metropolitan Government announced proposals to expand the rail network. One project would involve the construction of an 11km metro line which would run from Oshiage via a new interchange at Tokyo station to Sengakuji largely paralleling Toei's Asakusa Line. This standard-gauge line would be electrified at 1.5kV dc and provide through operation with Keisei Railway at Oshiage and with the Keihin Kyuko Line at Sengakuji. A line serving the rapidly-expanding waterfront area is also proposed.

Finally, there is a plan to upgrade existing freight tracks for passenger operation and to build a new connection to Haneda Airport which would enable JR East to offer a service between central Tokyo and the airport.

Tokyo has such a dense rail network that it is very difficult to find opportunities to build new lines even if some metro lines are operating at full capacity. Only full automation combined with shorter headways and station dwell times is likely to bring much relief to Tokyo's crowded rail services in the future.