Dubai metro - the world's longest automated rail system

David Crawford reviews the recent opening of Dubai's Red Line.

The US$7.6bn Dubai Metro, the Phase I Red Line of which started partial operation in September 2009, will be the world's longest driverless rail system on its planned completion in 2011. With a total length of some 75km, it will then overtake the 68.7km Vancouver SkyTrain and be able to carry over 1.2 million passengers on a typical day.

Train positioning is via an automatic radio-linked data Communication-Based Train Control (CBTC) system specially developed for urban rail operation. Operation is by a joint organisation of the RTA and Serco Group, which is running the Operations Control Centre (OCC), providing staff and taking responsibility for maintaining the rail infrastructure and rolling stock.

1676 Serco has brought to the role its existing experience in operating driverless metros - the Docklands Light Railway in London, UK, and the Copenhagen Metro in Denmark, which chose the solution in preference to a tramway for reasons of capacity. The Red Line runs on a mixture of underground and elevated tracks between Rashidiya, just beyond Dubai International Airport, and the new coastal development area of Jebel Ali. It has a design capacity of 3,500 passengers per hour and all stations are air-conditioned with platform-edge doors.

Construction started in 2006 on this, the first urban rail system in the Gulf Cooperation Council zone, which comprises the Arabian Peninsula. The Red Line opened to serve an initial 10 high passenger-load key stations out of a planned 29. These include Terminal 3 at Dubai International Airport, the Dubai International Financial Centre and the Mall of the Emirates (which claims to be the largest retail destination in the world outside North America).

The remaining stations on the Red Line will open in a phased programe due for completion by mid-2010. The Phase II Green Line, currently under construction, will expand the system to some 47 stations and have two interchanges with the Red Line.

Other routes are planned, and the 6700 Dubai's Roads and Transport Authority (RTA) sees the emerging network as the cornerstone of a future integrated public transport system.

Integrated philosophy

One of the key aims of that integrated system is to help reduce rising levels of traffic congestion, stemming from rapid growth in the population. This is expected to reach three million by 2017 and five million by 2020, by which time travel demand could rise to 22 million daily passenger journeys. Congestion is already estimated to cost the city state some US$1.4bn each year.

Prior to the opening of the Red Line, only some five per cent of the population was making regular use of public transport, in the form of buses and water buses. However, the Government hopes under the RTA's current transport master plan to raise that proportion to around 30 per cent by 2020.

Initial moves to encourage Metro use include keeping fares to the same level as those charged on the emirate's bus network, while at the same time branding the Metro as a prestige, not to say luxurious, system with Gold carriages available at a premium charge. Because of the subsidised fares, the Metro is not expected to make a profit, although the RTA estimates that it will generate revenue income of US$4.9bn over the next 10 years.

Better accessibility

The Metro will also tackle the issue of accessibility, which has not always been the first priority during Dubai's development as an international commercial centre, with little investment in public space. To encourage intermodal transport use, the RTA is locating bus stops close to Metro stations, with route adjustments where necessary and a network of 43 feeder services, using Citea buses manufactured by Netherlands-based VDL. Of these, 25 (including a free shuttle between the Ibn Battutah bus station and the Nakheel Harbour and Tower metro station) are already operating.

Bus take-up is being encouraged by the installation of a wide-scale real-time passenger information system, with priority in the rollout going to stops and waiting areas located at Metro stations.

The RTA's overall aim of creating a massive change in public behaviour away from the car has enjoyed an encouraging start, with over 110,000 passengers, nearly 10 per cent of Dubai's population, using the Metro on its first two days of operation and almost 367,000 trips being made in the first week.

The main contractor is Dubai Rapid Link (DURL), an international consortium comprising Mitsubishi Heavy Industries (MHI), three other Japanese companies (4962 Mitsubishi Corporation (MC), Obayashi Corporation and Kajima Corporation) and Yapi Merkezi Insaat ve Sanayi AS of Turkey. MHI and MC have supplied the rail system, including rolling stock, automatic train control, power supply system and tracks. Obayashi, Kajima and Yapi Merkezi have built the tunnels, station buildings and substructures for elevated rail tracks. The consortium is now engaged in building the Phase II Green Line, under the same role-sharing arrangement.

Signalling

The Metro's fully automated operation is based on 596 Thales Group subsidiary Thales Rail Signalling Solutions's SelTrac IS communications-based train control and NetTrac modular central control for urban rail transit, both managed from Serco's OCC at Rashidiya. The system is configured for a minimum headway of 90 seconds, with a maximum train speed of 90km/h.

SelTrac IS is a fully moving block-based member of Thales's SelTrac family of CBTC technology products. It is a development of a rapid transit solution initially introduced by Canada's Urban Transportation Development Corporation (later subsumed into Thales) and implemented on the Scarborough rapid transit line in Toronto, Canada's largest city.

Reduced headways, to achieve greater capacity, are one of the reasons for specifying the moving block system. Another is a reduction in the quantity of trackside signalling equipment needed, and thus of maintenance costs and service downtimes.

The moving block system allows trains to travel much closer to each other than in conventional fixed-block line-sector systems. Each train itself, together with short line sections ahead of and behind it - forming a safety zone - constitutes a moving block that no other train can enter. Its length is a function of the braking distance of the train, which in turn derives from its speed.

The onboard system continuously calculates its position and transmits this, along with other data including speed and direction of travel, to the trackside system. This in turn transmits to the train data on, for example, the maximum permitted speed at the time and the point along the track that the train can safely reach, continuously advancing this point in accordance with the moving block concept.

UK-based company Mainframe Communications has installed fibre-optic connections along both the Red and Green Line routes. Drawing on previous experience with London Underground its contract includes the supply of fibre-optic interface equipment, including 19 splice enclosures to join trackside cables and eight distribution frames to connect train and station control systems.

Its wall-mounted distribution frames contain equipment critical to the operation of the train and station management control systems via interfaces between vehicle onboard computers and Thales SelTrac IS vehicle control centres that cover both the Red and Green Lines.

The vehicle control centres constantly evaluate the status of the railway and vehicle positions by interfacing the onboard train controllers with trackside equipment. From the resulting data, they derive movement authorisations for transmission to trains within their control areas.

Mainframe has also installed four fibre-optic distribution racks, two at the main OCC and two at a back-up OCC at the Jebel Ali terminus. These interface Thales's SelTrac IS system with trackside equipment along both the Red and Green routes.

In a further contract, Thales has supplied a secure ticketing system, including access gates, ticket vending machines, at-station computers and a central control system. Fare payment is based on rechargeable 'Nol' ('fare') smartcards, bought from vending machines at stations, which can also be used to pay for travel on RTA buses and waterbuses and for parking at RTA locations - another move towards public transport integration intended to underpin modal shift.

The system automatically deducts the correct charge based on usage; cash is not acceptable as a method of payment. A gold card secures access to the 'luxury' Gold-class carriages.

Future

A new touch-on-touch-off (TOTO) smartcard-based fare payment system is scheduled to become operational by March 2010. One of its aims is to raise the efficiency of bus travel, as is an automated vehicle management system also due for implementation in 2010.

The RTA is currently reviewing its transport masterplan. The eventual rollout of its public transport network could include up to 318km of rail, some 270km of tram lines, 450km of water transport routes and around 2,500km of bus mainline and feeder services, according to a recent statement by Board Chair and Executive Director Mattar at-Tayer.

To mark the emergence of the Gulf emirate as a major new player in the high-tech transit field, the International Union of Public Transport UITP has chosen it as the venue for the 59th World Congress and Mobility & City Transport Exhibition in April 2011.