Assembly of membrane filters in the filter hall in Henriksdal. Photograper Mikael Ullén

15 May 2024

NIB finances Stockholm’s Future Wastewater Treatment project

NIB has signed a 10-year loan agreement with the City of Stockholm to construct the world’s largest underground wastewater treatment facility at Henriksdal. The aim is to accommodate a growing population, reduce overflow into Lake Mälaren and improve the quality of water discharged into the Baltic Sea.

The SEK 2 billion (EUR 172 million) loan will be used to double the treatment capacity of the Henriksdal wastewater treatment plant to serve 1.6 million people. The expansion involves closing the Bromma facility, rerouting wastewater through a new 14-kilometer underground tunnel to Henriksdal, which will become the largest membrane bioreactor technology facility in the world.

This technology will notably reduce phosphorous and nitrogen discharges into the Baltic Sea and decrease overflows of untreated wastewater into Lake Mälaren. Total project cost is estimated at SEK 22.5 billion and project completion is expected in 2031.

NIB has also previously approved loans for the project in 2016 and 2017. Total outstanding loans for the project amount to SEK 4.5 billion.

“The City of Stockholm very much appreciates the opportunity of debt financing of this project by NIB. This credit facility is a great complement to the bond market financing of our investments” says Sofie Nilvall, Treasurer at the City of Stockholm.

André Küüsvek, NIB President & CEO said “We are pleased to continue our support for Stockholm’s Future Wastewater Treatment project, which not only helps improve the ecological well-being of the Baltic Sea, but also aligns excellently with NIB’s mandate to enhance productivity and benefit the environment of the Nordic-Baltic region.“

Stockholm, Sweden’s capital and the most populous city in the Nordic-Baltic region, had a population of 988,943 at the end of 2023. As one of Europe’s fastest-growing regions, the city has a strong economy and a growing population.

NIB is an international financial institution owned by eight member countries: Denmark, Estonia, Finland, Iceland, Latvia, Lithuania, Norway and Sweden. The Bank finances private and public projects in and outside the member countries. NIB has the highest possible credit rating, AAA/Aaa, with the leading rating agencies Standard & Poor’s and Moody’s.

For further information, please contact
Tiina Kuusela, Senior Banker, at +358 10 618 0241,

Arild Moen, Associate Director, Communications, +358 10 618 0496,

Related resources

14 May 2024

City of Stockholm

EUR 172 million