Bus stops in Offenbach get green roofs

The roofs at the stops on Eibenweg, Seniorenzentrum Ost and Schönbornstraße have already been greened. The green roof is currently being installed at the bus stop at the hospital. The greening of street furniture is an important building block in the further development of infrastructure in times of global warming. Green spaces improve the urban climate because they provide cooling. The green bus shelters can also store up to 24 liters of rainwater per square meter. The green roofs also serve as building blocks for the biotope network, which are useful and important for insects. In the coming years, the number of green bus shelters is to be continuously increased so that the shelters as a whole can contribute to cooling down on hot days.

Green roofs combine ecological goals: It absorbs fine dust particles from the air and provides a micro-habitat for insects of all kinds. In addition, the roofs provide shade for waiting passengers, store water for cooling purposes and enhance the appearance of the bus shelters.

Sedum, popularly known as stonecrop, is planted and has many practical advantages. Sedum requires little rainwater and nutrients. Unlike moss, no additional water supply is necessary. Other advantages of sedum are its relatively low weight (around 50 kilograms per square meter at maximum water saturation) and its ability to bind pollutants. Carbon dioxide is absorbed and converted into malic acid. In sunlight, this is released and photosynthesized. The thick fleshy leaves of the sedum serve as a water reservoir and the evaporative cooling reduces heat on hot days. Different sedum species with different flowering times and colors turn the planting into a year-round biotope for insects.

The sedum planting is based on special structural foam mats made from recycled material. The mats can also be recycled after use. A substrate layer of pumice stone is laid on top. The structure is secured in an inclined, approximately eight-centimetre-high roof trough with a drainage device and drainage mats at the back.

"There are no additional costs for the city of Offenbach for this campaign. The idea for the project originated in the city's Office for Planning and Building. The original idea was to green advertising pillars. When the idea was further developed, the use of green bus shelters in collaboration with Ströer was an obvious choice, as this idea was already the focus of the green canopy on the market square," explains Paul-Gerhard Weiß, Head of Planning and Building. "We are starting with four bus stops, which we are currently greening. Five more bus shelters are to follow. We see the campaign as a pilot project and are gaining valuable experience in the process," adds Councillor Weiß.

The city of Offenbach's local transport plan for the years 2023 - 2027 also includes a review of the greening of further bus shelters. It will also be examined whether bicycle parking facilities at the stops should also be given a green roof. "It is important to us to provide both sustainable infrastructure and new spaces and paths for communication in public spaces. We therefore offer services for our customers and partners that make an additional ecological and social contribution. With our digital city media, for example, we are already enabling smart citizen communication in the sense of an urban system - a smart city. At the same time, the media carriers in public spaces are among the most energy-efficient and resource-saving media in terms of reach, with the lowest CO2 values in the entire media mix," says Alexander Stotz, CEO Ströer Media Deutschland GmbH.

With around 14,000 passenger shelters in Germany, Ströer is already an important part of the local public transport infrastructure. The company is investing in the further development of its infrastructure in order to offer additional functions for the sustainable development of urban systems ("Smart City").