With increasingly frequent water shortages and growing climate risks, water recycling is gaining importance. Under the leadership of the Karlsruhe Institute of Technology (KIT) and the RPTU University of Kaiserslautern-Landau, international partners are working in the European DECIRE-WATER project on innovative decentralized solutions for sustainable water management. After one year of development work, the researchers have put several demonstration sites into service to test the technologies under real-world conditions and make the necessary improvements.
Many regions face major challenges resulting from the climate crisis, demographic change, and increasing demands on water and sewage infrastructure. In the DECIRE-WATER project, researchers are developing decentralized treatment systems for different water flows. Not only will such systems make water reuse more efficient and economical, they will also enable the recovery of valuable resources such as the plant nutrients nitrogen and phosphorus. The systems can be used on a standalone basis or as a supplement for existing infrastructure, making them suitable solutions for individual apartments, housing blocks, or entire urban areas.
The project's focus is on nature-based solutions such as constructed wetlands. In basins filled with sand or gravel and planted with reeds or other plants, microorganisms break down pollutants and purify the wastewater. "Our aim is to combine the advantages of natural processes with technical solutions and systematically adapt water treatment to different requirements," said Dr. Verena Höckele, water technology department head at KIT's Project Management Agency Karlsruhe. Depending on the wastewater's pollution level, supplementary technical processes may be put to use, including membrane bioreactors for biological purification or UV systems for eliminating germs. Operation is continuously monitored with digital technologies to identify hazards at an early stage and ensure safe and efficient wastewater treatment.
Field Testing and Validation
At six demonstration sites in Europe and South Africa, RPTU is coordinating the scientific analysis of the systems' performance. "We're testing modular systems and digital technologies under real-world conditions. That's the key to marketable solutions that are economically and environmentally sound and enable climate-resilient water management," said Professor Heidrun Steinmetz, who heads RPTU's Resource-efficient Wastewater Technologies department.
In the project's next two years, the technologies will be continually refined to improve their practical implementation. Initial results encourage expectations that the technologies will enable reliable water reuse and that clean irrigation water can be provided even in locations with fluctuating water flow.
Holistic Approach to Water Reuse
The project features close cooperation among research institutes, companies, municipalities, and other partners. In addition to developing new technologies, they are also analyzing the economic, geographical, and legal conditions for water reuse. Life cycle analyses assess the ecological effects of the solutions developed, and workshops promote scientific dialogue and support the acceptance and future implementation of the technologies.
About DECIRE-WATER
DECIRE-WATER is funded under the EU's Horizon Europe research and innovation program. The project involves 15 partner institutions from Austria, the Czech Republic, Germany, Greece, Poland, South Africa, and Spain; it will run for three years with a budget of EUR 5 million
