Digital Sustainability

How can cities sustainably irrigate their trees despite increasing drought and water scarcity? The Branch Business & Information Systems Engineering of the Fraunhofer FIT is developing a data-driven solution for the intelligent, demand-based irrigation of urban trees and green spaces on behalf of the City of Frankfurt am Main. An IoT-based sensor network continuously monitors soil moisture levels. Combined with environmental, weather, and plant data, the developed application generates precise irrigation recommendations, leading to more efficient resource use and more resilient urban green spaces. 

Urban green spaces are crucial for quality of life in cities. Trees improve the microclimate, absorb CO₂, provide shade, and cool overheated urban environments. At the same time, increasing heatwaves and water scarcity pose major challenges for municipalities: particularly young urban trees require regular irrigation during their first years, which is still largely carried out manually and along fixed routes.

Within the project "Natural-digital Ecosystems for Water Savings" (NEWS), the Branch Business & Information Systems Engineering of the Fraunhofer FIT is developing a digital solution for demand-oriented irrigation of urban green spaces on behalf of the City of Frankfurt am Main. This is done in close collaboration with two key stakeholders: the municipal green spaces department, which manages approximately 8,000 young trees across the city, and the Palmengarten, which is responsible for green spaces in the botanical garden.

At the core of the solution is an agilely developed web application that processes sensor data from a network of more than 500 digitally connected soil moisture sensors. These data are combined with environmental and weather information and subsequently analyzed. The application supports both strategic planning and operational execution of irrigation activities. Irrigation planners can efficiently schedule operations, define prioritized irrigation needs, and monitor their execution by gardeners and irrigation service providers.

The project is funded by the Hessian Ministry for Digitalization and Innovation as part of the Starke Heimat funding program and will run until 2026. Looking ahead, artificial intelligence and machine learning methods will be applied this year to enable even more precise and predictive irrigation recommendations based on the data. At the same time, efforts are underway to increasingly utilize alternative water sources and reduce the use of potable water in favor of non-potable water. Another key objective is to make the software available as an open-source solution for other municipalities and to establish a nationwide development community together with interested cities. In this way, a scalable approach for data-driven and sustainable urban green space management is being created.