“Today, transportation planning must be approached differently than it was ten years ago. At the same time, Mainz’s downtown must remain attractive and accessible to everyone,” says Mayor Nino Haase. For him, this includes safe sidewalks and bike paths, easily accessible parking garages, and traffic-calmed and traffic-free areas, all of which contribute significantly to the quality of life for all Mainz residents.

A major problem for traffic in the city center recently was the construction site at the corner of Mainzer Netze and Umbach—between Große Bleiche and Große Langgasse. This coincided almost exactly with the launch of tram service on the renovated Binger Straße and the introduction of the “modal filter” on Große Bleiche. Several factors combined here, having a massive impact on traffic flow.

“The major projects coming from the direction of the main train station are now complete, and accessibility has improved dramatically. The project on Holzhofstraße will continue until fall—then we’ll be able to breathe a sigh of relief there as well. Over the next few years, we’ll still see many construction sites in all German cities, especially in the former East German states: The infrastructure must be renewed more or less simultaneously everywhere, and on top of that, there’s the expansion of sustainable district heating, broadband, and public transit. This will still require a great deal of patience, but at the same time, it’s how we ensure sustainable cities,” said Haase.

Construction sites for fiber-optic and district heating networks often have to be approved within short, legally mandated timeframes. The city of Mainz counts around 3,500 construction sites per year, although the city itself is not usually the contracting authority. “Of course, the transportation department coordinates the major projects we commission well in advance, and up-to-date information is available on our website. But given the sheer volume and short notice, perfect coordination is simply not always possible,” Haase emphasized.

With the recent completion of work on Umbach Street, Mainz is returning to normal operations for the first time—following the Münsterplatz construction site and the introduction of the modal filter. “We are, of course, comparing the new traffic data with the previously calculated models and expect traffic in the Bleichenviertel/Kaiserstraße area to return to normal,” summarizes Mayor Haase.

“Today, traffic planning must be more balanced than in the past—with a stronger focus on public transit, bicycling, and pedestrians. But of course, car traffic will continue to be taken into account as well. Mainz should remain accessible and livable for everyone—but in a growing city, available space doesn’t just keep expanding, which is why space-efficient modes of transportation like public transit or cycling must be given greater consideration than in past decades. To this end, we are collecting objective traffic data and will also share it.”

In September, the city administration launched a comprehensive data collection effort on the “modal filter” to test its effectiveness, monitor newly emerging traffic flows, and evaluate future developments based on a reliable data foundation. Once the data has been analyzed, various measures can be taken, such as adjusting traffic light phases or signage.

Haase concluded: “The Modal Filter project is being monitored with cameras and traffic counters to gather detailed insights into changes in traffic flows and congestion. These figures are then analyzed and evaluated. Traffic planning—including in Mainz—is data-driven, based on collected traffic metrics.”

In addition, the city administration has revised the collaboration between construction site marketing and construction site management. The Economic Development Agency is responsible for marketing, while the Road Traffic Authority handles management. Mayor Haase: “Both sides must work hand in hand and bring those affected—such as retailers and residents—into the spotlight whenever possible.”