As part of the cantonal SARS-CoV-2 wastewater monitoring, the Health Department of the Canton of Zurich (Cantonal Laboratory Zurich) analyses and publishes measurements of samples from twelve wastewater treatment plants (WTPs) distributed throughout the Canton of Zurich.
The measurements are based on the EAWAG (Swiss Federal Institute of Aquatic Science and Technology) project "SARS-CoV-2 in wastewater". Further information: https://www.eawag.ch/en/department/sww/projects/sars-cov2-in-wastewater/
Please note:
- The measurements of SARS-CoV-2 RNA in wastewater are partly subject to considerable measurement errors. Therefore, an interpretation of the wastewater measurements of SARS-CoV-2 in comparison to the case numbers is only meaningful over longer periods of time, addtional measurements such as the positivity rate and depends on the scale chosen. Consequently, the data should be interpreted with caution, as there is a large scope for misinterpretation. There are regular quality checks and it is possible that new knowledge will lead to recalculated values!
- Information about the WTPs included in the monitoring is available in a separate resource, including abbreviations, full names, locations (cantonal districts) and catchment areas (number of connected inhabitants).
Please note:
- Starting January 2023 sampling has been reduced to the WWTPs Bülach, Dietikon, Illnau-Effretikon, Winterthur and Zürich (Werdhölzli). Samples are taken three times a week
- To harmonise the calculations between the EAWAG and the Cantonal Laboratory, samples taken May 4, 2022 and later were recalculated. This resulted in higher concentration values.
- For the samples taken after December 30, 2021, the analysis method was changed. Comparison to older samples should be made with caution!
Wastewater samples are taken three times a week at the thirteen WWTPs. The analysis of the data is published once per week (on Tuesday). Starting October 2021 samples from the WWTP Winterthur are taken five times a week.
If you have questions regarding the content of the data, please contact the Division for Data Analysis of the Office of Health Care of the Canton of Zurich,
- by creating a GitHub issue or
- by writing an e-mail to gdstab@gd.zh.ch
If you have questions regarding the provision of the data, please contact the Specialist Unit for Open Government Data of the Canton of Zurich,
- by writing a Twitter direct message or
- by writing an e-mail to info@open.zh.ch
Many thanks for your feedback!
1. List of wastewater treatment plants with catchment area / Liste der Abwasserreinigungsanlagen mit Einzugsgebiet
Data
https://raw.githubusercontent.com/openZH/covid_19_wastewater_monitoring_ZH/master/ara_einzugsgebiet.csv
Description: Wastewater treatment plants, which are included in the monitoring, with respective catchment areas (i.e. number of inhabitants connected)
Update frequency: when necessary
Spatial unit: Canton of Zurich
Format: csv
Metadata
| Fieldname / Spaltenname | Description (EN) | Beschreibung (DE) | Format |
|---|---|---|---|
| ARA_code | Abbreviation of the wastewater treatment plant (WTP) | Abkürzung der Abwasserreinigungsanlage (ARA) | Text |
| catchment_area | Catchment ara (Number of inhabitants connected to the WTP) | Einzugsgebiet (Anzahl an die ARA angeschlossene Einwohner:innen) | Number |
| ARA_name | Full name of the WTP | Ausgeschriebener Name der ARA | Text |
| district | Cantonal district, where the WTP is located | Kantonaler Bezirk, in dem die ARA liegt | Text |
Data
https://raw.githubusercontent.com/openZH/covid_19_wastewater_monitoring_ZH/master/COVID19_Abwassermonitoring.csv
Description: Measurements of samples from wastewater treatment plants (WTPs) distributed throughout the Canton of Zurich
Update frequency: weekly
Spatial unit: Canton of Zurich
Format: csv
Metadata
| Fieldname / Spaltenname | Description (EN) | Beschreibung (DE) | Format |
|---|---|---|---|
| date | Day of sample collection | Tag der Entnahme der Probe | YYYY-MM-DD |
| SARS_CoV_2_RNA_copies_d_100000 | SARS-CoV-2 RNA in the wasterwater per 100'000 inhabitants | SARS-CoV-2 RNA im Rohabwasser pro 100'000 Personen | Number |
| quantification_flag | Possible value: 'Q'=above Limit of Quantification (> LOQ), 'D'=above Limit of Detection (>LOD), 'N'=below LOD | Mögliche Werte: 'Q'=über Quantifizierungsgrenze (>LOQ), 'D'=über Nachweisgrenze (>LOD), 'N'=unter Nachweisgrenze (<LOD) | Text |
| flow_m3_d | Flow of water into WWTPs in cubic metre per day | Zufluss zur Abwasserreinigungsanlage in Kubikmeter pro Tag | Number |
| sample_origin | Abbreviation of the WWTPs ('ARA_code' as in https://github.com/openZH/covid_19_wastewater_monitoring_ZH/blob/master/README.md#1-list-of-wastewater-treatment-plants-with-catchment-area--liste-der-abwasserreinigungsanlagen-mit-einzugsgebiet) | Abkürzung der Abwasserreinigungsanlage ARA ('ARA_code' gemäss https://github.com/openZH/covid_19_wastewater_monitoring_ZH/blob/master/README.md#1-list-of-wastewater-treatment-plants-with-catchment-area--liste-der-abwasserreinigungsanlagen-mit-einzugsgebiet | Text |