LëtzREUSE: An integrated tool for water reuse planning and risk assessment

LetzREUSE is a decision support tool (DST) designed to assist in the evaluation of urban water reuse scenarios involving rainwater, stormwater, light greywater, and wastewater treatment plant effluents. The tool integrates regulatory compliance, technology selection, predicted treatment performance, and ecotoxicological risk to support early-stage decision-making. In addition to treatment performance, the tool considers constraints defined by the user, being energy demand and space availability, ensuring that proposed treatment trains are not only compliant but also practical for implementation. Developed as a simplified and accessible framework, LetzREUSE does not require advanced modelling expertise or extensive datasets, making it suitable for practitioners, researchers, and decision-makers involved in water reuse planning. Instructions for use Download the compressed (.rar) file from Zenodo. Extract the contents of the .rar file to a local folder on your computer. Open the extracted folder. Locate the file named run_app. Double-click on run_app to launch the application. The tool will automatically open in a Streamlit interface in your default web browser.