Policy papers

Future-proofing urban waste water

2 June 2021

In societies around the world, water has long been understood to be a key resource that requires careful management. In Bali, for example, associations of farmers traditionally shared responsibility for river management. More recently, New Zealand designated legal personhood to its Whanganui River. And cultures everywhere have sanctified this life giving resource.

Managing the water cycle in modern cities, of course, takes a great deal more finesse than these examples of a single water way. In Scotland, for example, Ministers now have a duty to protect and enhance water resources, making it the first country in the world to do so. Nevertheless, an appreciation that water is a precious resource, both now and for the future, lies at the heart of city strategies, as presented in a new paper by Eurocities.

“The treatment of urban waste water from homes and workplaces is fundamental to ensuring public health and environmental safety,” reads the paper, which offers recommendations on the revision of the EU’s Urban Waste Water Treatment Directive.

Since 1991, urban waste water has been legislated at EU level. New challenges, such as more water runoff due to more extreme weather events, and contaminants such as micro-plastics, and meeting the objectives of the European Green Deal, however, mean that the original EU Directive needs to be updated.

Some cities, like Porto, are using nature-based solutions to help manage storm water, while decreasing energy consumption and absorbing carbon. These cities have included green spaces in their systems that can be temporarily flooded to help manage water by slowing its entry into conventional waste water systems to limit the amount of storm water ending up in sewers and overflowing. This also contributes to reduce energy use by diverting storm water away from collection systems and waste water treatment.

Eurocities advocates for the “adoption of preventative measures first” to address the cause of pollution and prevent the over treatment of waste water, requiring further resources. However, the network says one way to encourage this model behaviour could be through the “principle of polluter pays”. An Extended Producer Responsibility scheme, mandated by the European Commission, would put the onus on producers to finance the removal of specific substances they contributed to the waste water stream.

The network also highlights a huge underspend in financial investment in water services across Europe, but also identifies an opportunity to modernise current infrastructure. “With 37% of the Resilience and Recovery Facility funding dedicated to the green transition and the climate goals, member states have the opportunity to make the necessary investments in water services,” reads the paper.

Several cities, such as Paris or Gothenburg, are concentrating on developing their ‘blue infrastructure’. This involves any number of actions, such as building schoolyards that are more plant-based, that use more natural materials, and more permeable soil, or designing playgrounds that children still want to play in when it rains. The principle is rather simple: to manage rainfall as a resource, and understand how the city both impacts the natural water cycle and can work in harmony with it.

You can read the paper, including ideas on how waste water can be used to boost the circular economy, here.


Alex Godson Eurocities Writer
Louise Coffineau Policy Advisor (Water, Circular Economy, Climate)