The COVIDready project, funded by the German Federal Ministry of Education and Research under grant 02WRS1621A‑D, began in August 2020 and culminated in a 2023 report that documents the first nationwide, decentralized monitoring of SARS‑CoV‑2 in German wastewater. The consortium, comprising the Institute for Water Research (FiW) in Aachen, the Helmholtz‑Center for Environmental Research (UFZ), the Technical University of Munich, the Technology Center for Water (TZW), the Technical University of Darmstadt, and the University of Koblenz‑Gießen (KGU), coordinated the development and validation of a rapid, PCR‑based workflow that can be implemented in routine wastewater treatment plant laboratories.

Technically, the project established a 24‑hour composite sampling regime that feeds directly into a quantitative reverse‑transcription PCR (RT‑qPCR) assay targeting the SARS‑CoV‑2 nucleocapsid (N1 and N2) genes. Commercial kits from IDEXX, QIAGEN, and Promega were evaluated and integrated; each kit includes CDC‑designed primers and probes, an internal control (often pepper mild mottle virus for Promega), and a calibrated RNA standard that ensures inter‑laboratory comparability. The workflow, executed in the Ruhrverband‑operated laboratory in Essen and in the ISA environmental analytical laboratory, delivers results within 48 hours, with some samples processed on the same day. Key to this rapid turnaround is the use of automated RNA isolation modules that remove PCR inhibitors inherent to wastewater, coupled with strict spatial separation of pre‑ and post‑PCR steps to prevent contamination.

Beyond quantifying viral load, the project introduced a variant‑specific detection module. KGU supplied primer–probe sets that target signature mutations of variants of concern (VoCs). These assays were run in parallel with the standard N1/N2 panel, enabling early warning of emerging mutations in the population. In addition, the team validated digital PCR (dPCR) for mutation detection, demonstrating higher sensitivity for low‑frequency variants and providing absolute copy numbers that complement the relative quantification from RT‑qPCR.

Data analysis was standardized across sites using Python scripts that harmonized raw Ct values, calculated genome copy equivalents per litre, and applied trend‑detection algorithms. By integrating long‑term monitoring data from the TZW’s Karlsruhe plant, the project compared several trend indicators across pandemic phases, revealing that certain algorithms more accurately reflected infection peaks. These findings were presented at the 2023 Essen conference, underscoring the feasibility of wastewater surveillance as a real‑time epidemiological tool.

The collaborative framework was essential to the project’s success. FiW coordinated the overall workflow development and provided the central laboratory infrastructure. UFZ and TU Munich contributed expertise in environmental virology and assay optimization. TZW supplied extensive historical data and analytical support for trend analysis. TU Darmstadt and KGU focused on variant detection and dPCR validation. The consortium’s joint meetings facilitated the alignment of research questions, harmonization of protocols, and rapid dissemination of results. The project’s outcomes, including peer‑reviewed publications and a publicly available workflow guide, demonstrate that decentralized wastewater monitoring can deliver timely, reliable data on SARS‑CoV‑2 prevalence and evolution, thereby informing public health interventions at the municipal level.