THINK Blog DACH

In Zürich, the bright blue trams and sleek buses that crisscross the city are more than just transportation—they're the pulse of urban life. Residents and visitors alike rely on VBZ’s (Verkehrsbetriebe Zürich) integrated system to navigate the city’s winding streets, whether by tram or bus, ensuring that everything runs on time, no matter the weather. From commuters making their way to work to families exploring the lakeside, these dependable transport options are a symbol of Zürich’s commitment to seamless urban mobility and a reflection of VBZ’s well-organized and highly effective operations. Zürich itself boasts a robust and diverse multimodal public transport system, renowned for its efficiency, affordability, and easy accessibility—with stations typically within walking distance. These qualities have earned the city a consistent top ranking in global public transit indices, placing second in the public transit sub-index for the second consecutive year. As a result, public transport now accounts for an impressive 41% of the city’s total transportation volume, highlighting its crucial role in urban mobility and quality of life. 

Managing the Growing Volume of Customer Emails

This same expectation of quality is what VBZ brings not only to transportation but also to its customer service, that it also operates for ZVV - the public transport organization of the canton of Zürich. The region’s residents value reliable and efficient service, and they often reach out to the transportation provider with a variety of inquiries, ranging from route information to ticket pricing. Increasingly, VBZ found itself overloaded with customer emails, all of which had to be processed manually by a small team. The average time taken to respond to a customer enquiry was ten minutes. More complex customer enquiries that required information searches across multiple sources could take up to 30 minutes. 

Handling such high volumes created a significant backlog. The small team was forced to follow a “first-in, first-out” approach, making it difficult to prioritize urgent matters. Employees were often interrupted by calls or urgent tasks, making it even harder to keep up. As a result, customers faced long wait times for responses, which led to repeat inquiries and, ultimately, increased frustration.

Walter Weber, Mobility Expert at the ZVV-Contact Center, articulated the situation perfectly when he noted, “Unfortunately, I get interrupted by other work every now and then while writing emails and lose the thread. Then I have to start all over again, which costs me time.” His colleague, Carolin Schumann, echoed a similar sentiment: “I really enjoy answering customer emails, as the requests are very varied and sometimes complex. But when writing emails, I lose a lot of time on formalities such as structuring the text.”

The challenge was not only one of volume but also of maintaining a high quality of service. The small customer service team needed to balance efficiency with personalization, and the increasing volume of emails made this balance increasingly difficult to achieve.

Proof of Concept for the VBZ E-Mail Butler

Recognizing the need for a more efficient solution, VBZ partnered with the Client Engineering at IBM and UMB AG*[1], a trusted IBM Platinum Business Partner, to develop a Proof of Concept (PoC) for a new tool called the VBZ E-Mail Butler.

The UMB team was led by  Benjamin Sen as Team Leader for AI & Data, and supported by Senior Software Engineer Robin Schoch. IBM and UMB’s collaboration helped the project to incorporate advanced AI features and proven software practices. “Our role was to focus on creating a seamless integration of AI with VBZ’s existing processes,” explains the UMB team leader. “By aligning the automation solutions with their unique requirements, we were able to address their immediate challenges and lay the foundation for scalable future growth.”

The PoC was designed to address the very core of VBZ’s email management challenges by automating initial responses and categorizing incoming emails. The team’s expertise was central to building a system capable of significantly reducing the manual workload while maintaining high standards of service quality.

The solution was built around the existing knowledge base helping to increase the accuracy of AI-generated responses in alignment with VBZ’s tone and style. The assistant created draft responses for common customer inquiries, which agents could then review, edit if necessary, and send out quickly. The AI also categorized emails automatically, which would allow urgent requests to be prioritized in the future. Additionally, the system could be designed to help agents identifying and filter out spam and irrelevant content, significantly reducing the time spent sorting through messages.

A Collaborative Process

From the very beginning, IBM, UMB, and VBZ worked closely to align the solution with VBZ’s specific operational needs. The project began with a deep dive into VBZ’s existing processes. The team, composed of AI specialists from UMB and IBM, like AI Engineers, the Platform Engineers, the Innovation Designers and the Business Technology experts took time to understand the nuances of the email workflows, identify key pain points, and establish the main goals for the PoC. What followed was a period of intensive testing, where various AI models were evaluated for their ability to generate high-quality responses. The team iterated quickly, refining prompts and adjusting the models based on continuous feedback from VBZ employees.

Promising Early Results from the PoC

Despite its prototype status, the VBZ Email Butler demonstrated immediate value in user tests. The assistant was able to generate high-quality answer suggestions for about 20% of email inquiries, significantly reducing the agents’ time needed to respond to standard questions. This initial success showcased the potential of AI to enhance VBZ’s customer service capabilities.

The most important outcome of the PoC was the clear time savings it provided. Automating responses for repetitive inquiries freed up valuable time for employees to concentrate on more complex and high-priority cases. The AI’s ability to categorize emails accurately also meant that the team could quickly identify and respond to the most urgent messages, improving the overall efficiency of the service.

“The VBZ Email Automation Butler has shown that simple customer inquiries can already be answered well by a bot. If we introduce this solution, it will save us a lot of time, which we can then use to process more complex inquiries,” shares Benyamin Svensson, Team Leader at ZVV-Contact.

From PoC to Full-Scale Implementation

Encouraged by the success of the PoC, VBZ, IBM and UMB are now exploring ways to expand the AI capabilities to handle a broader range of inquiries and integrate with other communication channels. The goal is to implement a more comprehensive AI-driven email management system that can provide near real-time responses during peak periods.

“This Proof of Concept was more than just a technical exercise; it was a learning experience for both teams, and also an example of customizing IBM’s AI solutions, like watson Discovery, watsonx.ai, and Code Engine to deliver AI-driven automation tailored to the client’s needs” says Naim Zierau, Senior AI Engineer at IBM. “AI offers the potential to enhance the quality of VBZ's customer service and provide valuable support.”