Nature-based solutions for water resource management in the urban fringe

A research project called "Nature based solutions for water management in the peri-urban: linking ecological, social and economic dimensions (NATWIP)" started in 2019 and has the overall goal of: contributing to closing the water cycle gap by exploring the potential that nature-based solutions (NBS) offer to address water management challenges in landscape areas that have been neglected because they lie in the transition zones between the urban and the rural. Since NBS have most commonly been applied in urban areas, it is interesting to broaden the focus to assess the application of NBS on the outskirts of urban areas or the urban fringe as such areas are often affected by expansion processes of the city. Furthermore, these areas have historically played important roles in development and sustenance of urban centres, provision of water-related ecosystem services, particularly water supply, wastewater management and flood control.

Key NATWIP activities include the establishment of a methodological framework to analyse the social, economic and ecological sustainability dimensions of NBS and subsequently to apply the framework at case study sites in Norway, Sweden, Brazil, India, South Africa and Spain. These case study sites present very diverse water management problems as well as NBS. As more emphasis is placed on the use of NBS in the Nordic countries it is important to identify successful mechanisms for their implementation and monitoring. The case study site in Norway, Skien, represents a highly relevant urban challenge to balance water quality and the increases of water quantity as a result of climate change. This site focuses on the opening of a buried river using blue-green infrastructure as a catalyst for city development. In Sweden rain water harvesting in Gotland has been used in order to address water shortages caused by drought as well as water excess.

The other case studies sites present interesting examples where the framework is used to explore potential management practices that Nordic countries could learn from. In Spain, the Barcelona Metropolitan backbone is home to green-blue infrastructure and a variety of NBS that aim to improve environmental quality and water cycle management. The Brazilian case study focuses on the most advanced Payment for Environmental Service initiative in Latin America. Through this project, fees collected from water users pay farmers to conserve and restore riparian forests on their lands. In India rainwater harvesting is used to combat water scarcity and compromised water quality in new peri-urban areas. Two case studies in South Africa show how NBS can address the problems of water scarcity in combination with increasingly variable rainfall, frequent drought and floods as well as growing water demand.

Results from the first assessment of these case study sites will be presented to highlight similarities, differences, challenges, as well as potential synergies for learning from the different case study site contexts.