The Emscher river, flowing through the heavily populated Ruhr area, was long used as an open sewer system. This had a devastating effect on the landscape. The fluvial biodiversity seriously decreased, with many species disappearing completely. The river turned into a manmade system of open sewers and canals. The Emscher also lost its natural ability to retain rainwater, causing regular flooding. The 30-year project (1990-2020), developed and implemented by the Emschergenossenschaft in accordance with the EU Water Framework Directive 2000/60/EC, is the largest of its kind in the EU. Several milestones have been reached since the project began.

The Emschergenossenschaft Lippeverband (EGLV)

The EGLV implemented the Emscher Generation Project. Founded in 1899 and 1926 respectively, the Emschergenossenschaft and Lippeverband cooperated closely from the start, and work together under the single roof of a harmonised organisational structure. EGLV was the first German water management association in the form of a cooperative. The municipalities along the Emscher co-founded the Emschergenossenschaft and have been members ever since. Many of the industrial companies in the area are also members of the cooperative, which treats wastewater for them.

For 125 years, the Emschergenossenschaft has been responsible for all matters related to the Emscher and its tributaries. This includes water maintenance, flood protection, wastewater disposal, rain- and groundwater management, the restoration of the Emscher and general planning, consulting and implementing all measures required for the Emscher conversion.

Key learnings from the project include:

  • Water management is a driver of ecological and social transformation: It is necessary to think and act sustainably and in the long term to achieve the best possible climate change adaptation outcome.
  • Public water management in a cooperative: Broad participation of municipalities, citizens, politicians and NGOs, without profit orientation enhances project success and adaptation achievements.
  • Nature-based solutions (renaturation of water bodies and floodplains, near-natural retention areas) significantly contribute to carbon sequestration and the adaptation to climate change consequences. Additional blue-green infrastructure creates added value for living, living and working.

Nature-based solutions with tangible results

The renaturation of the Emscher proved a positive driver for structural change, bringing important natural and recreational areas to a region that was once characterised by mining and heavy industry. The project provided a blueprint for similar projects in Asia, Africa, Latin America and the USA.

The measures developed by the Emschergenossenschaft aim to achieve more natural and climateresilient water courses and involve acquiring more river areas through floodplain restoration and constructing near-natural wetlands and retention basins. The actions also include the construction of urban lakes to improve the urban micro-climate and enlarge recreation and leisure areas. De-sealing urban surfaces improved the urban water cycle, enhanced rainwater infiltration and reduced urban heat. Other measures to adapt to climate change include rainwater supply to the water bodies, the construction of extensive green roofs, façade greening and rainwater harvesting. Using organic materials to mow meadows, such as compost, soil fertiliser, or biochar, contributes to soil health and supports the circular economy approach to reducing the overall environmental impact.

The project brought impressive results, among which 170 km of renatured rivers (out of a planned 326 km), an increase in the number of species of invertebrates visible to the human eye from 170 to 300 (river basin level), 322 ha of new, near-natural flood retention areas built (of a planned 330 ha) and an increase from 38 to 147 bird species in the new near-natural flood retention areas.

Financing

The total investment for the project (including the construction of four Wastewater Treatment Plants) was EUR 5.5 billion. Wastewater fees financed 80% of this amount, and funding from the EU, national, and federal levels and other private funding sources funded 20% of the restoration project.

Part of this private financing are the proceeds of a green bond issued by North-Rhine Westphalia  state bank NRW.BANK, a regional German development bank.Triodos Euro Bond Impact Fund invests in the NRW.BANK Green Bond#2-2019 maturing in 2029. Aside from the renaturation of the Emscher (16% of the total bond proceeds), other financed projects fall into different categories, such as energy efficiency, onshore wind and solar, and clean transportation. The energy projects financed by this bond result in avoided greenhouse gas emissions of 1.3 million tonnes of CO2 equivalents over its 10-year term. Germany’s Climate Action Plan has targeted savings of 226 million tonnes of CO2 equivalents, and the savings achieved by projects in the asset pool represent about 0.6% of the total German emission target for this period.

NRW.BANK green bond framework

To finance nature-based solutions and other environmental projects, NRW.BANK has established a strong green bond framework since 2019, and recently updated in 2024. Projects eligible to be (re)financed through this framework focus on climate mitigation and climate adaptation.

The framework contains a wide range of eligible project categories: renewable energy; clean transportation; residential and public green buildings; aquatic biodiversity preservation and climate change adaptation; sustainable water management; energy efficiency; pollution prevention and control; sustainable management of land use and living natural resources; and circular economy adapted products and processes. Climate adaptation projects are usually not offered by green bond frameworks of financial institutions and are therefore particularly interesting.