Potsdam, in the former East Germany, is the first European city to adopt the standard new tram design by that country’s major rail vehicle builder, Siemens. It has adopted the latest design for the renewal of its tram fleet, ordering a total of 48 of the articulated, low floor units to operate services on its latest modernised routes.

The city’s proximity to Berlin means it has a healthy level of commuter traffic between the two. There is also a large amount of leisure travel in the reverse direction, with visitors to many of Potsdam’s fine ancient buildings. The city has a tram network which has been as much a part of the fabric of the city for the last century as some of these monuments since the first vehicles arrived in 1880. Electric trams were first introduced in 1907 when an 8km line was installed to replace the original horse-drawn vehicles.

It consists of five lines, with a total length of 25.5km, all of which converge on the city centre Potsdam Stadt interchange with the Deutsche Bahn heavy rail terminus. The central hub of the network has always been the main square, the Platz der Einheit, but over many years the system has been steadily expanded, largely to serve new residential areas.

The tram network is operated by Verkehrsbetreib im Potsdam (ViP), a fully owned subsidiary of the city authority, which also runs seven bus and one ferry routes.

The project

Around 17 million passengers use Potsdam’s trams and light rail vehicles each year, services generally operating between 04:30am and 11:30pm each day, and using 34 tram sets. In addition, there is one route that operates around the clock, and along with a night bus network, this means the city has around-the-clock public transport system.

The average speed on all four lines is 22km/h, which is not particularly fast, but the network boasts a total of 107 stops, so this cuts down the average speed, but at the same time encourages the maximum possible number of people to have easy access to and use the system.

Steady expansion of the network is ongoing, as it is extended mainly to serve new residential and industrial areas. A 900-metre extension opened in 1998 between Robert Baberske Strasse and Kirschsteigfeld serves a catchment area of 6,000 residents, while another residential area at Bornstedter Feld, is being linked to the network by a new 2.5km stretch of track.

Infrastructure

Just over half of the network runs over reserved tracks, meaning that there is no conflict with any other road vehicles. This allows a relatively high top speed for a city railway of around 60km/h (40mph) to be achieved.

All but 0.5km of the system is double track, and other measures used to avoid conflicts with other road users mean that almost three-quarters of the network has no contact with other road traffic.

As part of the upgrading which runs alongside the introduction of new Siemens-built Combino trams, a programme of station renaming has also begun. The most prominent of these is the re-christening of the Potsdam Stadt interchange with Deutsche Bahn heavy rail services as Hauptbahnhof.

Rolling stock

ViP ordered 48 of Siemens’ latest tram design at a cost of approximately DM140m, with the first one delivered from the company’s mass transit division factory at Erlangen in October 1998. This was after they had become the first vehicles of their type to undergo testing at Siemens’ Wildenrath Test Centre, the most modern facility of its kind in Europe.

“Progress of the trams is governed by an automated traffic management system, which can adjust the headways between trams to cater for fluctuation in passenger demand and peak-hour needs.”

The Potsdam vehicles consist of five sections, designed for unidirectional operation, with a completely low floor. The height of the door sills from the ground is just 300mm along the vehicle’s entire length.

The Potsdam Combino units have been given names to acknowledge their pedigree, with units Nos 401 to 404 being named Potsdam, Augsburg, Freiburg and Hiroshima respectively – the names being taken from other cities to adopt the Combino design for their latest light-rail vehicles.

While Combino is designed to be an off-the-shelf concept, adaptable for a wide range of uses, Potsdam’s own variant has several adaptations, major differences being increased passenger legroom, a different cab layout and changes to the passenger information system. Each Combino can carry 170 passengers, 69 seated, with space for two or three wheelchairs.

The fleet will be introduced gradually over ten years, a schedule chosen so that ViP can avoid having to meet legal requirements for the older generation Tatra vehicles, which they are set to replace, to undergo rigorous government checks.

Signalling and communications

Improved passenger information displays have been included as part of the overall programme of system renovation. This has involved the installation of a dynamic, real-time information system showing the progress of trams in service, similar to that widely seen on the London Underground. The large displays are being lauded by ViP as a major innovation in increasing ease of use of the system, thereby attracting passengers from other modes of transport.

Progress of the trams is governed by an automated traffic management system, which can adjust the headways between trams to cater for fluctuation in passenger demand and peak-hour needs.

The future

Potsdam city council continues to follow a policy of extending the tram network to serve new and growing residential areas. The Bornstedter Feld extension is due to be completed by 2001, in time for the city’s hosting of the national garden festival (Bundesgartenschau).

This route is important for ViP for, after several years of expansion to the southern areas of the city, it redresses some of the balance in the north. Local residents will be consulted as part of the planning process, primarily to determine the optimum location for stations on the new route. Disabled groups are also being asked what facilities they would like to see incorporated.

ViP sees its tram network as part of the face of its city, and the upgrading is helping it present a modern image to the millions of visitors to the capital of the Land Brandenburg state each year.