The majority of communities in Europe have combined sewer systems. In a combined sewer system, both wastewater and stormwater flow through the same pipes. During heavy rain events, the combined flow of wastewater and stormwater can exceed the capacity of the pipes. To address this, approved outfalls are strategically placed as relief points during wet weather. These outfalls release untreated or partially treated stormwater and wastewater into nearby water bodies, and these releases are termed Combined Sewer Overflows (CSOs).
The goal of this short survey is to understand
- what, if any, CSO performance data (e.g. spill frequencies and duration) are available at utilities
- for which purpose they are being used
- the motivation of different stakeholders [operators and regulators (academia, consultants)] to publish performance indicators on CSO (or not)
Dear wastewater professionals,
as part of the EU project "Collaborative Urban Drainage Labs" (Co-UDLabs), we are researching the availability and use of data to evaluate the performance of urban drainage systems. We are particularly interested in the availability of key figures, such as the functioning of combined sewer overflows (CSO), in the context of "Open Government Data".
The survey can be completed conveniently online and takes 10-15 minutes, depending on the size and tasks of your company. Please complete one form per drainage system, if possible. If your organization manages several or many, please provide the info for one or two typical systems. We know wastewater systems vary widely; please skip questions not relevant or interpretable for your country.
If necessary, please forward this questionnaire to the responsible person in your organization. Your information will be stored anonymously and external parties will not have access to your answers.
Thank you for your participation, your input is very important to our efforts to improve drainage planning and environmental protection.
If you have any questions or need assistance, please do not hesitate to contact us at contact@co-udlabs.eu.
Best regards, in the name of the Co-UDLab partners,
Elodie Brelot (GRAIE) and Jörg Rieckermann (Eawag)
P.S.: An initial synthesis of the survey will be discussed in the second half of 2024. If you provide us with your contact details, we will be happy to inform you of the results.