EIB backs Stockholm’s SEK 19.5bn wastewater overhaul with €470m loan

The European Investment Bank (EIB) has committed €470 million to Stockholm’s comprehensive wastewater system upgrade, a project aimed at reducing Baltic Sea nitrogen discharge by 40% and securing the city’s drinking water supply. The financing supports the consolidation of treatment facilities by 2031.

The European Investment Bank (EIB) is providing SEK 5 billion (€470 million) to finance a major overhaul of Stockholm’s wastewater infrastructure, representing approximately 26% of the total SEK 19.5 billion investment.

The project entails decommissioning the Bromma treatment plant and channelling all sewage through a new collection tunnel to an expanded Henriksdal facility, which will employ advanced membrane technology to increase treatment capacity without expanding its physical footprint.

The upgrade is projected to cut nitrogen discharge into the Baltic Sea by roughly 40% and phosphorus discharge by about 35%, while also enhancing the removal of microplastics and preparing for future treatment of pharmaceutical residues.

Officials note the initiative reduces risks of untreated wastewater spills into Lake Mälaren, the city’s primary drinking water source. This development is strategically significant for water-intensive industries and environmental compliance. The project supports Sweden’s obligations under the Baltic Sea Action Plan and the EU Water Framework Directive.

For investors and municipal policymakers, the long-term financing structure—aligned with a 2031 implementation timeline—demonstrates a model for funding large-scale urban environmental infrastructure.

The EIB, the European Union’s long-term lending institution, focuses on supporting climate action and environmental sustainability.

The City of Stockholm, as the borrower, is executing one of its largest-ever environmental capital projects through this partnership.