Restoration of the Østerå river system as an ecosystem service for the ecological transition of Aalborg

Abstract

The first document approved by the European Community on sustainable urban development was drawn up in Aalborg in 1994. The Danish city has distinguished itself on the international scene for pursuing sustainable growth through energy transition, nature conservation and urban regeneration. To increase the city's resilience to climate change and to improve the quality and ecosystem balance of urbanized environments, Aalborg has launched projects for the reactivation of interrupted natural cycles and the renaturalisation of abandoned urbanized areas. One of the most significant projects is the restoration of the Østerå, the river that ran through the city and which, at the end of the 19th century, was channelled into underground pipes to make room for urban growth. The entire course of the river will be brought back to the surface, redeveloped and equipped as a new ecological corridor according to an innovative approach that rediscovers the aesthetics of wild nature. The project will increase the multiple benefits that a river can bring in an urbanized context as an ecosystem service. The opening of the river will contribute to the mitigation of flood risk with Rainwater Harvesting and Management systems, will increase the value and quality of public spaces and will allow residents to have a direct experience of nature in the city.