The cable car as a new dimension for urban mobility solutions

Impressive views, no traffic jams and no emissions: Whether as a lift on a skiing vacation, as a means of transport in a pleasure park or as a connection between a city district and the National Garden Show - a cable car trip is always an experience. Mainly implemented for tourist purposes so far in Europe, it comes under repeated discussion as a means of local public transport.

In other latitudes one has long since recognised its potential of being able to overcome distances and differences in altitude in an environmentally-friendly and practically noiseless way without having to take the paths of roads or terrain structure into account, which in turn allows its easy integration into local public transport networks. In this way, cities in South America, such as the Capital of Bolivia, La Paz, or the Colombian metropolis, Medellín, have firmly integrated cable car solutions into their transport systems over the past years. The original purpose of the "cable car", i.e. travelling between different heights, is still the main reason for implementing such a system today - but not a precondition. For example, a cable car network opened in 2014 that now spans a distance of more than 30 kilometres through the metropolitan area of La Paz, which has an elevation difference of more than 1,000 metres. Mi Teleférico has two aims – to relieve the pressure on the road transport network and to ease mobility-related segregation dynamics. With ten lines currently in operation, the capacity of the public transport network, which consisted only of minibuses before the cable car system’s construction, has increased exponentially. Every day, more than 300,000 passengers now use the cable car network, which runs between the low-lying outskirts of La Paz, the steep slopes at the heart of the city and the high plateau of the immediately adjacent El Alto, a city with a population of one million. Similar effects can be seen in Medellín, where the outlying districts situated in steep, hilly terrain have been connected to the centre of the city since 2004. As in La Paz, mobility has been improved here too and the acute segregation problem has been resolved. As a result, even the crime rate dropped within five years of the gondola lift system going into operation.

Although the concept and production of cableway systems are deeply rooted in Europe, cities in this part of the world are still comparatively conservative about implementing cable car systems within their transport networks. This is demonstrated, among others, by numerous proposed projects in various large German cities (e.g. in Wuppertal, Hamburg and Cologne), which were ultimately rejected by local referendums or district councils, in some cases after having reached the final stage. In each of these cities, the aim was to increase the accessibility of certain districts cut off from the city centre by barriers (differences in elevation, waterways, building developments) by constructing a cableway. As a result, most urban cable car systems in Germany are still mainly tourist-oriented for the time being.

However, Koblenz is an example of how well-accepted cable car systems are. Built in 2011 for the National Garden Show, the cable car there was supposed to be long-since dismantled - however a citizen initiative in Koblenz asserted itself so that it could be retained. Since then, in total 18 electricity-powered cabins, have been gliding from the station at the bottom to the left of the Rhine not far from the Deutsches Eck (German Corner) up to the Ehrenbreitstein Fortress. With a passenger capacity of up to 7,600 people an hour, the cable car transports the visitors in a smooth process primarily to events held at the fortress - indeed a true local means of transport, albeit with a purely touristic background in this case. During the garden show alone, just under seven million passengers opted for the cable car ride over the Rhine. Also beyond this there are 210 cableways in Germany - 124 of which are located in Bavaria - all of which are used for tourist purposes.

However, cable cars are coming under closer consideration as a means of urban local transport in Germany too in the face of the increased traffic jams, noise and emissions. Since particularly in larger cities, the streets and public transport networks are reaching their limits or have long-since exceeded them. Although cares are only used for an average of about one hour a day, the German passenger car fleet grows by between 500,000 and 700,000 vehicles annually. "The construction of underground railways is expensive and new streets are hardly possible anymore due to lacking space. A new way of thinking has come about due to the sustainability principle that is being actively promoted in Germany more and more. A very good alternative of designing the cities in a greener and more eco-friendly way in future, could thus be the implementation of urban cableways in the so-called 'Level +1'," said Sebastian Beck, an infrastructure expert at the Stuttgart-based planning and consulting company, Drees & Sommer SE. Whereby he noted that it is essential that they are integrated into the public transport network.

In order to determine the prerequisites and options of such an integration, together with the Verkehrswissenschaftliches Institut Stuttgart GmbH (VWI) for the Federal Ministry of Traffic and Digital Infrastructure (BMVI), Drees & Sommer is currently putting together a national guideline on the city and traffic planning integration of urban cableway projects. The aim is to boost the construction of cableways and sustainability concepts in urban spaces and thus make the infrastructure "greener". An overview on the "Realisation of cableways as part of the local transport network" is to be available in around a year. The genesis of the project is a change in the law at the beginning of 2020 that declared cableways to be part of the local transport network eligible for funding. "The focus lies above all on social and political aspects, the comparison of costs and usages as well as the introduction of a national standard. But first and foremost it is about weighing up where a cableway is actually practical and where not," explained Sebastian Beck. There is no patent solution for an urban cable car system. The infrastructure, the volume of traffic or the topography is different in every city. What would work perfectly in City A, may make no sense at all in City B. That is why each location has to be considered individually, regarding whether a cableway would be practical."

In the first instance the cableways in the cities Medellín, La Paz, New York, Portland, Algiers, Lisbon, Brest, Bolzano, London and Ankara are being examined to determine the optimum use of the cableway, its integration into the urban planning and linking it up with the local transport network. Ultimately, cognitions for possible cableway projects in Germany will be derived from this. In addition to the integration into the local transport network, the backing of the citizens also plays an essential role. Although building a cableway was often fiercely contested beforehand "the people from the locations where they have been installed wouldn't want to miss their cableway anymore". A transparent process is thus the be all and end all. And that can in turn only succeed if the population is 'carried' along with this theme from the very onset. Because the concerns of the people can only be taken into account and eliminated if a dialogue is sought and matters actively communicated - this is also one of our goals on compiling the guideline," the infrastructure expert stated. Concern and criticism often exist regarding the route and the fact that the pillars erected will have a negative effect on the cityscape or the fact that the passengers will have a view of the private properties when the cable cars glide over them. "This problem can be solved thanks to modern technology," said Sebastian Beck. "The so-called 'Privacy Glass' could at times obscure the window panes during the ride to protect the view over the private properties."

In terms of city and building planning, Sebastian Beck sees urban cableways as an opportunity for new perspectives and concepts. "Integrating a route with its individual stations into a city would be much better than originally thought. Example: A station could be easily planned on the roof of new commercial properties or warehouses. We simply have to move away from the accustomed way of thinking that a building is fundamentally entered via the ground floor or basement. It is namely equally possible from the top."

Cable car systems offer the biggest opportunities for a more sustainable and more liveable alignment of public traffic: Traffic jams, air pollution and traffic noise are forcing cities to reduce the existing burdens. To a great extent, the cable cars use the airspace independently from the remaining traffic: "They hardly cause emissions themselves - when operating using renewable energy they even achieve zero emissions. Furthermore, they do not compete with cars, buses or trains, but are instead a supplement to them instead, opening up a new, third level of mobility. What's more they are quiet, safe and efficient. It is difficult to generalise on the ecological characteristics of cableways, because they always have to be examined in the context of the local conditions and demands," elaborated Sebastian Beck. "Nevertheless, it has already been scientifically proven that in comparison cableways have a very low power consumption even if they have a high transport capacity. This is due to both their technical construction through the mutual cancellation of mass ratios as well as due to their extremely energy-efficient drives. Since these are also operated using electricity, the ecological footprint of a cable car system is much lower than that of other means of transport."

If one looks at the CO2 emissions of different means of transport per person and per kilometre, cableways produce the best result, explained Sebastian Beck: "With a utilisation capacity of just 50%, a cableway causes 27 g of carbon dioxide, a train with an e-locomotive 30 g, a bus with a diesel engine 38.5 g and a car with a combustion engine 248 g indeed. Hence, in the overall ecological equation, the cable car is the most environmentally-friendly mobility solution. On the assumption of a service life of 30 years, the cableway produces a quarter of the amount of tonnes of carbon dioxide equivalent (tCO2eq) compare to the other means of transport. As such, cable car systems have the smallest ecological footprint. The survey results were audited by three independent institutes."

The transport capacity of 7,600 people an hour of the cableway in Koblenz provides an idea of the huge potential that cableways could yield as an urban means of transport. Such transport capacities would bring about true relief in coping with commuter traffic. For example, at a speed of around 21 km/h, the Wuppertal cable car would have covered a distance in nine minutes that would take a car in rush hour traffic about twice as long and a local bus three times as long. With a construction time of one year and comparably low construction costs of twelve million Euros, the example in Koblenz clearly demonstrates that cableways could quickly help relieve the mobility balancing act in Europe in a fast and cost-efficient manner.

Sebastian Beck took a degree in Infrastructure Management at the Technical University of Stuttgart. At the beginning of 2010 he started working with the infrastructure experts of Drees & Sommer focusing on development, rail infrastructure, energy and cableway projects. Since October 2016, Beck has been responsible for the Infrastructure Department at the location Baden-Wuerttemberg. Furthermore, in his capacity as a lecturer at the Technical University of Stuttgart for the course of studies Infrastructure Management, he passes on his knowledge in the construction and real estate management sector.