Department Urban Water Management

POLAAR - Policy and Actor Analysis of Urban Water Infrastructure Management in the Age of Digitalization

Improvements in water protection not only require technical solutions

Wastewater treatment plants (WWTPs) are built to treat all wastewater during dry weather. During wet-weather, however, much more water is discharged into combined sewer systems and the capacities of the WWTPs are often exceeded. Since the 1970s, combined sewer overflows and overflow tanks (CSOs) have been built to collect polluted rainwater runoff. These CSOs store mixed wastewater temporarily or discharge it directly into rivers and lakes.

Despite today's technological possibilities, CSOs are often not operated optimally for various reasons:

  1. In some cases, there is a lack of monitoring data on the storage and overflow behaviour of CSOs.
  2. If monitoring data is available, there is often a lack of understanding for the handling of the data. For     example, data is logged incorrectly, or only evaluated for operational aspects, such as alerts in the event of malfunctions. For an effective implementation of the requirements in the Swiss water protection law, not only authorities should know whether the systems are functioning well or not so well, but the data should also be prepared and archived for future planning.
  3. Organisational responsibilities are often not clearly defined. Even if a WWTP treats the community's wastewater, the WWTP operator does not necessarily operate the CSOs as well and therefore cannot influence their performance.

All above problems indicate that in many Swiss municipalities current infrastructure is operated in such a way that the potential capacity is not fully used.

The aim of the POLAAR project is 1) to identify existing organisational and political obstacles to the effective operation of CSOs and 2) to develop policy instruments that could be effective as measures or incentives to overcome these obstacles.

With the support of the FOEN (Federal Office for the Environment), the interrelationships in Swiss practice will be examined more closely. The focus is on monitoring specific municipalities over the duration of the project (longitudinal study). Structured interviews with representatives of authorities, industry, professional associations and science are planned. Comparisons will be made with examples from neighbouring countries where other legal requirements and ordinances apply.

In the long term, the use of policy instruments in practice could help to improve water protection during wet-weather by applying technological innovations (sensor technology, wireless data transmission, automated data evaluation). To ensure that all stakeholders (municipalities, wastewater associations, authorities, planning offices, etc.) benefit from the ongoing digitalization process, we are developing proposals for a uniform, common strategy (policy) for Swiss urban water management.

What is the network of information exchange and coordination between stakeholders, e.g. authorities, wastewater associations, drainage planners, who are active in the management of urban wastewater infrastructures? What are their responsibilities, knowledge, needs and perceived challenges? What could be good incentives, for example to establish a regular performance reporting?