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Tram-train: Making new connections

The first section of the Paris T11 Express opened in June 2017; Citadis Dualis 312 is at Epinay-sur-Seine on a service bound for Bourget. Image courtesy of Sébastien Godefroy

The announcement by Transport for Greater Manchester (TfGM) that its strategy for the next 20 years to expand its Metrolink rapid transit network includes tram-train suggests that the concept is gaining momentum.

Well-proven around the world, tram-train combines the flexibility and accessibility of a tram network with the speed of a heavy rail system, enabling passengers to get directly into a city centre, shopping or business district without having to switch modes. Offering seamless interchange, it enables sharing of infrastructure with conventional rail services although tram-train vehicles (commonly derivatives of low-floor LRV platforms) require adapted signalling and power supply capacities, specific wheels, as well as control and telecommunications technology that allows them to run on both light and heavy rail networks.

The concept has many more benefits over single or mixed-mode travel, says Philippe Bernard, Director of Tram Train Projects at SYSTRA, which has designed and delivered tram-train systems around the world: “The tram-train option works brilliantly for cities or large towns seeking to extend their coverage via the conventional rail network. Tram-train links adjacent economies by improving connectivity between cities.

“The rolling stock can accelerate and brake almost in the same way as a bus,” he adds. “Tram-trains can also travel at speeds of up to 100km/h (62mph) on railway lines [tramway operational speeds are lower]; run on tramway lines as well as conventional rail infrastructure, with certain adaptations; climb gradients of 8-10%, depending on the chosen propulsion method; and where appropriate, operate at a minimum curve radii of 25m.”

Expanding Metrolink

At 97.5km (60.6 miles), Greater Manchester’s Metrolink light rail network is already the largest in the UK, with services running on seven lines and serving 93 stops. This will expand by another 5.5km (3.4 miles) in 2020 with the opening of the new Trafford Park Line (see TAUT 980); an additional 27 trams are on order to bolster the existing 120-strong fleet.

Further to this impressive expansion of its light rail system, tram-train could be a game-changer by increasing the network’s reach still further by connecting Metrolink with existing rail lines outside the main conurbations.

In January 2019, then-Secretary of State for Transport Chris Grayling said: “A Greater Manchester tram-train has the potential to seamlessly integrate our existing rail and tram tracks and services,” and added that the UK Department for Transport would work closely with TfGM to explore such proposals.

The transport authority is exploring the possibility on a number of routes under the ten-year ‘Our Network’ vision outlined by Mayor of Greater Manchester Andy Burnham in June 2019. Three ‘pathfinder’ routes are progressing to the business case stage, designed to test the viability of tram-train technology: Altrincham – Hale; Bury – Rochdale; and Manchester Airport – Wilmslow. It is likely that the Bury – Rochdale route would share part of the heritage East Lancashire Railway. A wider roll-out includes routes south-east from Manchester to Marple, east to Glossop, west to Wigan via Atherton, and south-west to Warrington Central.

But before that can happen, TfGM says there would need to be a trial scheme with Network Rail to gain technical approvals. If this is the case, it will need to absorb some of the learning from the South Yorkshire pilot that has seen tram-trains running on Sheffield’s Supertram network and continuing on the main line railway to Rotherham since October 2018.

This government-funded pilot programme is a partnership between South Yorkshire Passenger Transport Executive (SYPTE), which owns the tram infrastructure in Sheffield; Network Rail, which owns the national rail infrastructure; Stagecoach, which operates Supertram services; and rail franchise holder Northern Rail.

Stagecoach currently operates three tram-train services per hour on this section of the network, utilising specially adapted Stadler Citylink LRVs and tram tracks between Sheffield Cathedral and Meadowhall/South Tinsley before crossing onto a new 170m section of track (the Tinsley Chord) that allows the connection of 80lb tram rails to 113lb rail tracks. The route then continues for another 5km (three miles) to Rotherham Parkgate via Rotherham Central on the national rail network.

At the moment this is still officially a pilot scheme, with SYPTE monitoring customer satisfaction, passenger numbers and reliability. If successful, the tram-train section will continue to run as a local service and any lessons learned will be used to inform other potential tram-train projects in the UK.
The innovative South Yorkshire service carried over a million passengers in its first year, and this success has led to the exploration of the feasibility of other routes across the region.

An increasingly popular concept

Elsewhere in Europe, tram-trains have performed a vital service for over 25 years. The first tram-train service was introduced in Karlsruhe, Germany, as a way of increasing mobility by connecting the city’s tramway to under-performing suburban rail lines while also taking cars out of the central areas.

It started operating as a fully-shared system between the rail and tram operators in 1992, and improved service frequencies and additional tram stops near residential areas saw ridership grow rapidly. The system has expanded significantly since then, with passengers now able to travel from towns such as Baden-Baden, 30km (18.6 miles) away, directly to destinations in central Karlsruhe without having to change modes.

The success of the ‘Karlsruhe model’ has led other European city regions to introduce tram-train networks, including those in Alicante, Saarbrücken, Kassel, Paris, Aarhus, Den Haag and Utrecht; it is also being considered as part of the South Wales rail network upgrade programme. Significant expansion is planned in France and Germany, and the concept has been introduced in the US.

SYSTRA has designed and delivered many tram-train projects including those in Aarhus, Denmark, and Mulhouse and Nantes-Châteaubriant in France. “All of these schemes have a common goal: to extend the existing urban transport network into the surrounding region”, says Mr Bernard.

Despite this expansion, there are currently no international standards for tram-train design or operation. Many cities still use the original rules developed for Karlsruhe as a yardstick to measure a proposed scheme’s viability. Recent years have seen moves towards standardisation of vehicles however, with the Verband Deutscher Verkehrsunternehmen (Association of German Transport Companies, or VDV) leading an ‘alliance’ of operators and authorities looking at opportunities for joint procurement to reduce costs by up to EUR1m per vehicle (see TAUT 968, 977 and 981).

Mr Bernard says tram-train works particularly well in cities or regions where there is disused or underused conventional rail infrastructure, or those operating vehicles on semi-urban equipment with multiple level crossings and stops. He explains that it is cost-effective as long as it can be done without needing to build significant new infrastructure: “Tram-train is an economically-attractive solution as long as the programme is limited to the redevelopment of an existing line and does not impact too much on its surroundings, and providing that levels of availability and reserves of equipment have been defined at the early stages of the project and shared with the transport operating authorities.”

Stephen Ware, Senior Project Manager at TSP Projects, a SYSTRA company, who worked on the South Yorkshire pilot, says this is one reason why the Meadowhall – Rotherham route was chosen: “The existing railway runs very close to the tram network, so we could put a short link in from one
piece of infrastructure to the other, and provide benefits to various places on the route.”

Paris and its suburbs

One city-region that has embraced tram-train very successfully is Paris. While the city’s Metro is undergoing massive expansion under the EUR22.6bn (GBP19.3bn) Grand Paris Express programme – four new lines totalling more than 200km (125 miles) to be delivered by 2030 – tram-train is seen as the best way to open up under-served suburban areas and encourage people to use public transport through new rail-based connections.

The Greater Paris region currently has four tram-train routes either already in operation or under construction. The oldest is the T4 line between Bondy – Aulnay-sous-Bois in the north-east of the city. France’s first tram-train line, the former low-frequency regional commuter line that dates from 1875, was converted to tram-train operation with new Siemens rolling stock, increased frequencies and additional stops. It opened in November 2006.

In mid-December 2019 a 6.5km (four-mile) extension is to open, linking directly into the national rail network by branching off at Gargan station at the line’s approximate mid-point. The cost of the new 11-stop line is estimated at EUR270m (GBP230m) for infrastructure work and a further EUR100m (GBP86m) for additional rolling stock, Citadis Dualis vehicles supplied by Alstom. Funded approximately 86% by the Île-de-France region and the State, and 14% by national rail operator SNCF, the vehicle and operational costs are being financed by Paris transport authority Île de France Mobilités (formerly known as STIF – Syndicat des Transports d’Île-de-France – until its rebranding in 2017).

In the meantime, another new tram-train service has started operating in the northern suburbs: the T11 Express. This 10.6km (6.6-mile) line between Epinay-sur-Seine – Le Bourget opened in July 2017 and serves seven stations and was created by laying two new tracks along an existing freight alignment.

The T11 Express, originally known as the Tangentielle Nord or Tram-Express Nord, is eventually planned to become a 28km (17.4-mile) route between Sartrouville in the north-west of Paris and Noisy-le-Sec to the east. The project is being co-ordinated by the Île-de-France region, Île de France Mobilités, SNCF and the municipalities of Seine Saint-Denis and Val d’Oise, with the EUR603m (GBP517m) cost split between Ile-de-France (47%), central government (27%), SNCF (24%), Seine Saint-Denis (2%) and Val d’Oise (1%).

This line is also served by Citadis Dualis vehicles, and like T4 is operated by SNCF and its subsidiaries.

Also under construction is the T13 Express line in the western suburbs. Being built in phases, the first 18.8km (11.7-mile) section brings tram-train services from the existing RER station at Saint-Cyr to Noisy-le-Roi on a currently-disused segment of the Grande Ceinture (GC) freight route, and from Noisy to Saint-Germain GC on a section that currently carries passenger traffic.

Around 4km (2.5 miles) of new infrastructure is being built to join Saint-Germain GC to an interchange with RER line A at Saint-Germain-en-Laye; six new stations are being built with a further five being refurbished. The new route is due to go into service in 2021 with ridership predicted at 21 000 passengers/day.

The EUR306.7m (GBP263m) project is being financed by Île-de-France (53.2%), the municipality of Yvelines (30%) and the central government (16.8%). Île-de-France Mobilités is financing the EUR68.4m (GBP58.65m) purchase of tram-train vehicles (again of the Citadis Dualis type, ordered in a joint procurement for T12 in 2018). In the longer term, a northern extension to Achères via Poissy is planned, taking passenger numbers up to 40 000 a day.

A further route, the T12 Express, is under construction between Évry-Courcouronnes – Massy-Palaiseau RER stations to the south of Paris. This 20km (12.4-mile) route, with 16 stops, is due to open in 2022.

The importance of collaboration

The introduction of tram-train in France is not limited to Paris, says Mr Bernard: “Other projects are scheduled to be launched across the country in the coming years to enable the gradual replacement of lines currently served by regional express trains, or to reopen lines with a conventional rail system abandoned due to low levels of use.”

Mr Bernard, Project Director of France’s first tram-train (the T4 line between Bondy and Aulnay-sous-Bois) and also involved in the T11 and similar schemes in Mulhouse, Bordeaux line C and Nantes – Châteaubriant, says every new project comes with its own specific technical and operational challenges. However, they all have a ‘transition zone’ where the operating, power supply, signalling and telecommunication systems are changed if the infrastructure necessitates it. “Integration into an existing network – and especially the definition of its transition zone – is the most complex issue the project faces and must be fully understood from the preliminary design phase,” he says.

As most countries use different bodies to regulate heavy rail and urban tram or light rail operation, he adds: “The main challenges exist in getting these two different worlds to co-habit, so they communicate and co-operate during design phases, and are compatible in operation and maintenance.”

The UK regulatory and operational landscape is more complex than most. Different organisations own the rail and tram infrastructure; rail services are operated by franchised companies, often with more than one franchisee operating on the same lines; trams may be either privately or publicly-operated; and different regulators and bodies oversee everything from safety to ticket pricing. “There is no worldwide way of implementing tram-train,” says SYSTRA Engineering Director Derek Small. “And there is no one way of doing it in the UK, because no two tramways are the same in the UK. Every system is bespoke, so the application of tram-train is bespoke.”

Because of this, Mr Bernard says it is vital that all the main players are involved at the earliest possible stage: “The method employed to maintain and operate the line must be accurately defined from the very start and, if possible, validated by those who will work on it in their respective areas.”

Mr Ware says this is one of the lessons that must be learned from the South Yorkshire pilot programme: “When working with two separate operators that have different requirements, such as signalling, it can be a challenge to make it work. On the Sheffield system we worked with the two operators to ensure that the project was completed and the tram-train operated successfully. That may not always be the case on other schemes unless parties go the extra mile to ensure requirements are co-ordinated effectively”.

Moving forwards with future tram-train projects, Mr Ware believes that for a smooth and successful operation all parties need to work collaboratively together, dovetailing their programmes and requirements to deliver a streamlined solution.

Experience in other countries shows that, if all these issues can be ironed out, tram-train is an extremely attractive proposition with many benefits for municipalities, operators and passengers alike.

As Philippe Bernard concludes: “Tram-train constitutes an economical transport system in terms of cost, investment, maintenance and operation, and enables passengers to travel safely from the city centre to surrounding cities several dozen kilometres miles away – the potential for the UK is huge.”

Article appeared originally in TAUT 985 (January 2020).