Cities around the world have an increasing necessity for urban mobility. Growing populations mean more citizens and longer distances to serve, and without efficient public transport this equals more vehicles on congested road networks.

Excessive growth in private car usage in previous decades is being countered with effective and sustainable modes, and the modern tram is today considered an optimal solution for consolidated urban zones with severe traffic challenges in constrained areas.

Facing this reality, in 2009 the Spanish city of Zaragoza (around 310km/190 miles between Barcelona and Madrid and the principal stop between the two for national rail operator’s Renfe AVE high-speed services) confirmed its plans for a 12.8km (eight-mile) tramline linking the peripheral neighbourhoods from north to south, crossing the city centre and the old town. This ambitious proposal has its roots in a longer-term Sustainable Mobility Plan dating back to 2003.

At first, the plan faced strong opposition from different community groups, but today bears out the success of these decisions with accurate and quantifiable data around improvements to air quality and a significant reduction in private vehicles in the city. Zaragoza fulfils not only the requirements demanded by national legislation, but also exceeds even the highest requirements of the World Health Organisation (WHO). With its latest published data, the WHO highlights the dramatic reduction of PM10 micro-particulates since the introduction of the tram. The city environment currently features levels of 18.1μgr/m3 (microgrammes per square metre), well below the WHO recommended maximum of 20μgr/m3.

Zaragoza is the fifth largest city in Spain by population, after Madrid, Barcelona, Valencia and Seville. However, by surface area it is the largest of them all by a considerable margin with 938km2 – the capital, Madrid, covers 35% less land at 606km2. This size results in an extremely low population density: 724 people/km2, far below Madrid (5335 people/km2) or Seville (4981 people/km2).

As such, Zaragoza is a city with a high degree of urban sprawl. Recent urban developments of subsidised housing such as Valdespartera and Parque Goya have contributed not only to the dispersion of the city, but also the demand for mobility and the average distance displacements.

Having such a high demand for social mobility requires a public transportation network with high capacity, high comfort and high commercial speed to avoid huge increases in traffic in the central city areas. Some cities may have chosen to build a subway to carry out this task; Zaragoza has relied on the tram – and this decision has proven to be the correct choice.

Currently, SEM Los Tranvías de Zaragoza transports 29m passengers per year, offering 28.74% access to properties around stops in the southern area of Valdespartera, revealing great impact in peripheral neighbourhoods.

Average occupancy is 21.93 passengers/km, confirming the high demand for the service. Line 1 has the highest patronage of any tramline in Spain – the second-placed line has half this figure – and carries an average of more than 100 000 passengers per working day in a city of 700 000 people. With just one line, this further illustrates the crucial nature of the investment in public transport and its high usage.

The key to this success is that line 1 connects the city to the growing northern and southern districts, crossing areas that generate significant ridership, including the city’s largest hospital, all three University campuses, the football stadium, some of the biggest neighbourhoods (Romareda, Actur, Casablanca), sport centres, key tourist sites and monuments and large retail centres.

As transport sustainability is associated with the level of occupation, in this sense, each Zaragoza tram user only contributes CO 2 emissions of 71.49g/passenger km.

Beyond these impressive achievements in ridership and air quality in analysing the effect of the advantages seen since the introduction of line 1, it has to be highlighted that there have been great improvements in the urban environment of the city, prioritising clean transport. This has caused a reduction of traffic of an average of 7.68%. This is more significant in the downtown areas of the city, where the investment in tram infrastructure has contributed to a reduction of 32.3% in Plaza Paraíso (Zaragoza’s most important traffic hub) and 29.39% in Paseo Pamplona.

Fewer vehicles, less jams, less noise

When the proposals for line 1 were first presented, many people predicted that with fewer lanes for cars and more pedestrianised areas there were would be significant increases in traffic jams. In reality, the established line has had the opposite effect. In seeking a quick, regular and comfortable mode of travel, increasing numbers of people are choosing to leave the car in the garage and opting for the public transport option.

These results were verified in a study by navigation and mapping company TomTom in 2014. Its research analysed the traffic densities inside the core urban areas of 60 European cities, 14 of which were in Spain. It concluded that Zaragoza is not only the European city with the least traffic congestion, but also, if these results are analysed in a worldwide context, Zaragoza is the seventh best city in terms of congestion of the 200 studied cities.

One of the best examples of how the city has changed is Calle Coso. This ancient street, the old boundary of the Roman city, was used by 7-8 buses every minute before the tramway was implemented. Now, it is a pedestrian area in the heart of the city.

With 25 stops in each direction, the average distance between them is about 500m and the end-to-end travel time across the city by tram is 40 minutes, with an average service speed of 21km/h (13mph). Punctuality is one of the system’s strongest values. Passengers are not subject to the

same traffic constraints thanks to dynamic priority of the city’s traffic signal system and with a frequency of five minutes during peak hours and a service availability of 99.98%, the timetable is very accurate. It can be consulted in real-time via our website www.tranviasdezaragoza.es

With all these benefits, 24% of passengers now use the tram instead of the private car. In the last satisfaction survey, the confidence level in the service was 95.5, within a global overall satisfaction figure of 8.01/10.

With fewer cars, there is also less environmental noise. The city council has developed a noise map of Zaragoza and drawn the conclusion that the installation of the tramway has reduced noise in the city centre by 7.5dB at Plaza de España and Calle Coso – a very high figure.

Zaragoza goes green

The construction of line 1 has not only brought better air quality, less traffic, less congestion and fewer accidents, but the tramway project was also conceived as an opportunity to create a greener city.

The route features more than 42 000m2 of natural grass, all with drip irrigation; the line’s stops also have sedum plants on their roofs. This type of vegetation, suitable for arid land, requires no maintenance and – beyond its aesthetic contribution to the city – preserves the freshness of the stops and reduces UV radiation in the surrounding environment.

Efforts to provide enhanced green spaces in the city did not finish with completion of the line’s construction. In 2016, the company Los Tranvías de Zaragoza has planted 114 trees along the boulevards of Gran Vía and Fernando el Católico as previously agreed with the neighbourhood. In total, the company has planted 1600 trees across the city since 2009.

Technical sustainability

Sustainability and environmental commitments are two key elements in placing line 1 in its proper context. The Urbos 3 low-floor tram, manufactured in CAF’s factory of Zaragoza, has an Onboard Energy Storage System (OESS) which provides intelligent power management and recovers braking energy in an optimised hybrid system of batteries and supercapacitors. As a result, the trams themselves are up to 35% more energy efficient. Tranvía de Zaragoza vehicles were the first in the world to obtain the Environmental Product Declaration according to ISO 14025, in 2011.

Along a 2km (1.2-mile) stretch in the historic city centre, the tramway runs catenary-free, drawing traction power to recharge its systems using surface-contact technology. This has been developed with the SIL4 (Safety Integrity Level) certificate, the highest security level for this type of technology. It is an innovative solution developed in a city that relies on technology to improve.

Also, thanks to traffic signal priority being applied in the context of a consolidated city transport network, thousands of stop-start movements for the tram are avoided each day to improve the overall flow of mobility throughout the city. The tram service has greater punctuality, the passenger’s travel experience is more comfortable and it is easier to adapt frequencies to the real traffic circumstances in Zaragoza.

In the city context, the Urban Mobility Service, through the Traffic Control Centre, manages a traffic light network with 650 signalled intersections, 20 communication points, 400 measurement points, 67 traffic cameras and a central computer.

Intermodality

Creating true intermodal travel options has also become possible since the introduction of the tramway. For the city’s residents, an integrated combination of bus, tram, bicycle and pedestrian areas means simpler and more convenient door-to-door journeys; Zaragoza is a very favourable city for pedestrians and the tramway has only enhanced this aspect, with new areas within the city that are car-free.

A cycle lane has also been created along the length of the tramline, and this mode has now become a phenomenon in Zaragoza, an otherwise flat and dry city that is perfect for cycling. At the same time, the introduction of the tram has allowed the reorganisation of bus services into a ‘fishbone’ structure where the central axis is the tramway’s line 1. On the tram, urban bus services, and also on the buses to the peripheral towns, shared ticketing makes it easier to travel with one ticket.

To further encourage travel by public transport, line 1 has two park-and-ride sites at the entrance of the city from both the north and the south, with discounted fares for tram users. Leaving your car and travelling into the city by tram costs users just EUR0.06/h.

Local and environmental initiatives

Focusing the tramway at the heart of the communities it serves, Tranvía de Zaragoza invests heavily in social initiatives, giving priority always to those related to sustainability.

For example, in 2017, Tranvía de Zaragoza sponsored the 9th International Film Festival of Zaragoza, ECOZINE, that every year shows and rewards the best documentaries, feature-length and short films related to environmental protection.

SEM Los Tranvías de Zaragoza also collaborate in the International Urban Art Festival of Zaragoza, ASALTO. Each year noted Spanish and international artists design artworks that feature on the tramstops. These paintings are displayed along the line for several weeks.

Recently, Zaragoza Tram has collaborated with the Official Association of Architects of the region, explaining the significance and history of the main buildings along the line to passengers as they travel on the system.

When the first tramline project was completed in 2013, the impression was that Zaragoza had changed its appearance. But four years on the city has realised that the depth of the changes is far more fundamental, and goes to the heart of Zaragoza. Its citizens have grown with the city, changing their routines, avoiding private transport and actively creating a better place in which to live and work.

Zaragoza has become a proud international showcase for future urban mobility thanks to line 1, receiving visits from delegates from 222 cities of 63 countries. Political representatives, public organisations, transport operators, engineers and technicians have come to the city to study line 1’s technology, urban development or transport governance.

Verified results Improvements to the city have been studied by CIRCE, an independent university institute. Its research evaluates the environmental impact of the tram in aspects such as traffic, impact on existing bus routes and the effects on peripheral neighbourhoods of the line. In its conclusions, the research gives evidence that the tram has contributed significantly in improving mobility and air quality in the city of Zaragoza for the following reasons: * The occupancy rate of 21.93 passengers/km is 4.4 times higher than a standard city bus. * The specific energy consumption of the tram is 0.18 kW/user km – 85% less than a city bus. * The specific CO2 emissions are 71.49 grams/year – 79% lower than a city bus. * Despite covering just 7% of the total distance of Zaragoza’s public transport, the tram transports 25.04% of the network’s overall passengers. * The tram saves 189 661.64MWh +/-9.5% per year. This amount of energy is equivalent to the consumption of 19.6m litres of diesel fuel. * Comparing the annual consumption of total energy of the system (vehicles, stops, workshops and offices) of 9068.02MWh/year in annual savings, the study concludes that for every kWh consumed by tramline 1, it saves 21 kWh. * The tramway avoids the emission of 49 027.48 +/-10% tons of CO2. This is a 6% reduction of CO2 emissions associated with mobility. * The tram has reduced traffic by 7.68% across the whole city, 32.3% in the city centre. * The tram has reduced NOx emissions by 491.72 tons/year, CO emissions by 293.21 tons/year and emissions of solid particulate matter (PM10) by 16.82 tons/year. These values show reductions of 17.73%, 8.83% and 49.11% respectively from 2009.

Originally featured in January 2018 TAUT (961).