WarnMe: Rethinking Early Warning
The idea for “WarnMe” originated from their own experience with flooding: “In 2016, a flood in Ochsenhausen caused significant damage to our school. A few years later, we picked up the idea of a warning system and started developing it ourselves,” explain Jana Spiller and Niklas Ruf.
Their approach is deliberately simple and accessible. A network of low-cost sensors measures water levels and flow velocities directly on site. Installation is straightforward, data is analysed in real time, and in the event of danger, users receive immediate push notifications via the associated app.
From an expert perspective, this approach is highly convincing: “A key advantage is that the results are easy for residents to understand,” emphasises Dr Piroth. “This helps create a clear awareness of the potential risk.”
Big Impact with Simple Means
What makes the project particularly remarkable is its open approach. “Anyone can build their own measuring station.” With costs ranging between €50 and €100, the system is significantly more affordable than many established solutions and is therefore of particular interest to smaller municipalities and local initiatives. Interestingly, the greatest challenge was not the technology itself, but communication: “We quickly realised that traditional channels like email are not suitable for time-critical warnings. That’s why we decided to develop our own app, allowing us to notify users directly.”
Practical Relevance
In the context of increasingly frequent heavy rainfall events, they see significant potential: “Small rivers and streams in particular can lead to flooding very quickly. This is exactly where we offer a cost-effective and efficient solution.” Dr Piroth also sees strong potential in such approaches: “Innovative, low-threshold technologies will play an increasingly important role in the future. They are flexible, cost-effective and widely accepted.”
Looking Ahead
In addition to technical insights, the two mainly took away new connections and inspiration from the forum: “We hope to meet people who are already active in the water sector. These contacts can be very helpful for further developing our project.”
Their long-term goal is clear: “It would be a major step to implement WarnMe on a wider scale and contribute directly to flood protection.”
The Flood Forum in Mannheim once again demonstrated how important the dialogue between experience and fresh ideas is and how much innovative potential lies in the next generation.

