Research

The Study on the reliability of Water Supply Services is part of study series. For 2025 the focus will be on aging infrastructure and the need for renewal, as these issues have been cited for the fourth consecutive year in the study series as the greatest future challenge from the perspective of water utilities. The study will examine the potential impacts of aging infrastructure on the reliability of water supply services. It will supplement the results of the annual survey—which covers standard questions such as exceptional events, restrictions, and challenges—with a focus on the aging of the pipe infrastructure and an individual assessment of the need for renewal, and will contextualize these findings in relation to the results of previous studies.

Given falling groundwater levels and rising demand, using drinking water alone to irrigate green spaces is not sustainable. The GRAUfürGRÜN-BLAU project is investigating the use of treated gray water from residential buildings for irrigating public green spaces and for groundwater recharge. At two locations in Vienna (Kauergasse 2 and Pogrelzstraße 8), the quantity, quality, and utilization potential of the gray water produced are being measured. The aim is to develop technical, legal, and organizational solutions for the provision of treated gray water at the interface between private buildings and public green spaces. Ecological risks such as pollutant input and microplastics are also being analyzed, and filter solutions for infiltration are being tested. In addition, an economic evaluation, an analysis of acceptance by the population and administration, and barrier-free processing of the project results are being carried out. The project contributes to resilient, climate-adapted cities and offers replication potential for municipalities with comparable supply structures. The aim is to ensure the availability and performance of urban GI even under future climate conditions – without having to resort to valuable drinking water.

Nature-based solutions (NBS) for wastewater treatment (WWT) are important technologies for climate change mitigation and water reuse practice. While stand-alone numerical models exist for such NBS none are capable for the integration planning and upscaling in urban water management tools. Therefore, model development and integration needs to be addressed by a holistic approach reaching from detailed process-based models to provide in-depth understanding, machine-learning approaches based on available data as support and the upscaling by surrogate models for planning tools and stakeholder discussions. Three objectives are defined (i) UPGRADE existing models by expanding the number of pollutants that can be modelled; (ii) CONNECT process-based and data-driven models to achieve better prediction; (iii) UPSCALE the developed approaches by creating surrogate models that can be either applied as stand-alone models for design purposes or included in decision support tools for urban water management. With the inclusion of the scientific community from the beginning, this model development has a high impact and will be widely used. Following the three objectives a clear path from process understanding and research-oriented model to the inclusion of experimental data towards the simplification by surrogate models is drawn. The emergence of hybrid modeling as a new tool in NBS for WWT is a long-term expected outcome that will allow scientists to consider phenomena not easy to conceptualize for their predictions. This also will close the gap between researchers working on numerical models, engineers and researchers carrying out experimental investigations The proposed data exchange format and willingness of researches to share their data this project provides a high impact on the field of research.