Water reuse is a key pillar of water security and sustainable resource management. FiW supports municipal and industrial stakeholders in developing, validating, and implementing reuse concepts- from initial feasibility assessments to full-scale realization. Our approach combines engineering consultancy, applied research, and international cooperation, with the goal of transforming treated wastewater into a reliable resource while systematically integrating energy and material flow considerations.
We develop, support, and advise pilot and implementation projects across all relevant reuse contexts: Direct Potable Reuse (DPR), Indirect Potable Reuse (IPR), and Non-Potable Reuse (NPR). We address both municipal and industrial wastewater streams and design site-specific multi-barrier concepts that integrate technical feasibility, operational reliability, regulatory compliance, and economic viability.
Our services include:
- Potential and demand assessments
- Selection and design of appropriate treatment technologies
- Development of monitoring and quality assurance frameworks
- Risk assessment and validation strategies
- Techno-economic evaluations, including energy and material flow analyses
A particular focus lies on the practical piloting and implementation of pilot-scale demonstration facilities. We design, construct, and supervise modular and containerized pilot systems, support commissioning and operational optimization, and evaluate performance data to inform validation processes and scale-up decisions.
In addition, we implement training and knowledge transfer formats -ranging from operator manuals to on-site and digitial training programs- to sustainably strengthen local operational capacities and facilitate the transition to routing operation.
We consider water reuse a part of a broader circular economy framework. Therefore, we also address qestions related to closing material cycles, including;
- Nutrient recovery
- Brine and sludge management
- Integration with energy recovery pathways
- Integration of nature-based solutions
- Productive reuse approaches such as hydroponics and aquaponics
Our projects are implemented nationally and internationally as consultancy mandates, research, and development projects, and collaborative research initiatives with partners from academia, utilities, industry, and regulatory authorities.
Selected International Projects and Pilot-Scale initiatives in Water Reuse and Resource Recovery
ecReUse (South Africa)
Funded by the Federal Ministry for the Environment, Climate Protection, Nature Conservation and Nuclear Safety (BMUKN) the project operates and scientifically evaluates a containerized pilot plant for municipal wastewater reuse. The core component is a membrane bioreactor (MBR) with ultrafiltration, complemented by continuous sand iltation as a polishing step. A comprehensive monitoring and analytical framework enables performance evaluation, while operational, regulatory, and economic boundary conditions -includng energy pathways such as sludge-to-biogas recovery- are assessed in parallel. The facility also serves as a demonstration and training infrastructure.
WaterReTUNE (Tunisia, 2019–2023)
Funded by the Federal Ministry of Science, Technology and Space (BMFTR), this completed project developed and demonstrated integrated pilot approaches for advanced treatment and valorization of treated wastewater effluents. The focus was on robust multi-barrier concepts, cost-efficient desalination, nutrient recovery, nature-based solutions, and practical aquaponics approaches. Technical evaluation was supported by monitoring programs, energy analyses, and economic assessments. The pilot infrastructure continues to be operated locally and is used for training purposes.
Hawassa Industrial Park (Ethiopia, 2020–2022)
On behalf of GIZ, we supported the technical and organizational stabilization of wastewater treatment at Hawassa Industrial Park. Key activities included root-cause analyses, establishment of standardized operation and maintenance procedures, and targeted capacity building. The objective was to achieve reliable effluent quality, strengthen plant management, and establish a suitable operator organization.
We are also implementing projects in Germany that combine water reuse with enhanced nutrient removal and productive applications. For example, the AbWiFaser project (funded by BMFTR, investigates plat-based post-treatment approaches combined with hydroponic cultivation to improve both water quality and resource efficiency.