ANCHOR - Capacity building for circular wastewater management

To make cities more sustainable, resources such as water, energy, and materials need to become more circular.

Society's waste products need to be better utilised and reused, including wastewater which contains not only water but also energy and nutrients. Conventional wastewater systems focus on recipient protection, which means protecting the water body where treated wastewater is discharged. In many large wastewater treatment plants, biogas and heat are extracted, but nutrients are only returned to agriculture to a limited extent. Today, the recycling of treated wastewater is uncommon in Swedish municipalities. If focus is instead placed on resource recovery, these can be reused more efficiently while also reducing emissions to the recipient.

When wastewater is separated into different flows directly in buildings, and these streams are handled and treated separately, it facilitates the reuse of nutrients, heat, biogas, and water. Keeping the wastewater streams separate, from household to treatment facilities, contributes to:

• More efficiently capturing resources such as energy, water, and nutrients.
• Reducing environmental and health impacts.
• Decreasing the load on pipes and treatment plants.

Over time, this approach may also reduce the need to expand drinking water production and wastewater treatment. The project ANCHOR, Anthropocene Nutrient and Water Control for Holistic Resilience and Recovery, brings together European water companies, municipalities, and academic institutions from Sweden, Germany, the Netherlands and Belgium to share experiences from five pilot projects with source-separating wastewater systems. By evaluating technology, analysing benefits and costs, and identifying barriers and opportunities, the project aims to create a shared knowledge base to facilitate and accelerate the transition within the water and wastewater sector.

In Stockholm Royal Seaport, a source-separating wastewater system is being investigated for 550 apartments in Saltkvarteren, where greywater will be collected, treated and reused for irrigation of the area's parks and street greenery.

Purpose and Goals

The aim is to develop a knowledge base concerning source-separating wastewater systems and water-efficient communities targeted at decision-makers in urban development. This will be achieved by evaluating pilot projects and developing tools and manuals based on the results. The goal is to contribute to more resource efficiency in the water and wastewater sector.

Results and Experiences

The project began in September 2023 where several studies have been initiated, including those on driving forces, benefits and organisational aspects. Work is underway to develop methods for measuring the systems' technical performance, and based on the knowledge generated in the project, a planning manual and an action plan proposal will be developed for interested municipalities. Since the project started, six lunch seminars have been held which can be accessed at:

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