On 13 February 2019, members of the Association for Geographic Information were invited to visit the Edinburgh Tram depot and control room.
The Edinburgh Tram opened in 2014 after a complex and controversial project history. However, passenger patronage demonstrates the popularity of the scheme, with the 2018 figure of 7.3 million customer journeys well above even the most optimistic forecasts, growing by 40% over the last three years. Passenger surveys indicate a satisfaction rate of 99%, which is six points above the industry average.
The tram line currently serves the city centre from Edinburgh Airport and Ingliston Park and Ride, by-passing the congested road corridor at Corstorphine and passing through the financial district of Edinburgh Park. There is a rail interchange at Edinburgh Gateway, near the airport, which allows access to the airport from the north and which sits at the hub of land allocated for future development, a welcome test of the policy of providing enabling infrastructure to support future growth.
The depot itself is located between the airport and the Gyle shopping centre, close to Edinburgh Gateway. The tram operational team consists of around 180 employees, mostly drivers and revenue protection staff, with an engineering, administrative, control room and management team. The managing director, Lea Harrison, provided a comprehensive introduction and briefing at the beginning of the visit.
The tram scheme was a longstanding proposal of City of Edinburgh Council, following various innovations including the very successful park and ride network and bus priority routes and the less successful guided busway, attracting Scottish Government funding for three tram routes around the city on an east-west loop and southwards to the hospital and bio-quarter. After various high profile project problems, this was curtailed to the Airport to York Place route, but a proposal to extend the route to Leith will soon be decided upon by city councillors. A preliminary design already exists for this extension and much of the troublesome underground utility diversionary work was completed prior to the abandonment of the route, lessening potential concerns about the extension. The current tram network also provides a central “critical mass” for extension, delivering a profit two years ahead of schedule, similar to the way in which the highly successful Manchester Tram scheme has been extended.
The 14 kilometre network relies upon twenty-seven tram vehicles, which were procured at the outset of the project to allow detailed design to meet vehicle performance requirements. The AGI delegation was pleasantly surprised when we were told we would be allowed to drive a tram on a short stretch of track, under supervision of course. The vehicle is simple enough to operate, with a single lever, but with an extensive array of CCTV screens and safety devices. Driver training takes some 8-12 weeks and is comparable with heavy rail driver training. Unlike heavy rail, the rail points are changed by the driver rather than by signallers, although the AGI delegation was not allowed to proceed quite that far.
The vehicles are maintained in an engineering facility, which mainly functions during a night-time window of a few hours when the network is not operational. The power system is 750V DC and inherently lethal, so a system of steps and locking gates allows access to the top of the vehicle and the various electrical components. Power is delivered by overhead catenary wires that are attached to poles or to building fixings, depending on the historic character of the area, with fixings favoured where key views may be obscured. A pantograph rises from the vehicle, to connect with the overhead lines and the electric current, delivered from six sub-stations along the route. The sub-stations provide some redundancy so, if a section of overhead line is disabled, the remainder of the network can still run.