Author(s): Sebastian Schwindt; Gregory B. Pasternack; Silke Wieprecht

Linked Author(s): Sebastian Schwindt, Silke Wieprecht

Keywords: Nature-based solutions; Habitat suitability; Vegetation; Terraforming; Wood

Abstract: The scientific and non-scientific literature provides multiple strategic guidelines, hydro-morphological principles, and ecological objectives for river restoration. Strategic approaches consider socio-economic decision-making processes to satisfy as many stakeholders as possible (e.g., fisheries, nature conservation associations, farmers, insurance holders, and residents). From a hydro-morphodynamic point of view, restoration actions should be self-maintaining and dampen floods rather than worsen the situation. From an ecological perspective, river restoration should instate and support dynamically ecological functions, including creating physical habitat for as many key fish species as possible with the correct timing for each of their lifestages. The implementation of socio-economic, hydro-morphodynamic, and ecological objectives is a great challenge for planners because of the involvement of multidisciplinary expertise and limited budgets. In this process, state-of-the-art two-dimensional (2d) numerical models and nature-based engineering features are commonly used tools. This study uses a metaphoric house of Nature-based Solutions (NbS) as a workflow to systematically achieve multiple objectives as a science-based consensus method. The house-of-NbS workflow starts with a framework of terraforming features, furnished by vegetation plantings, and wood features. The workflow maintenance involves interventions to sustain sediment dynamics, such as gravel augmentation to ensure the balance of the sediment budget of a river reach. The sequence of application of measures, the involvement of 2d numerical models, and technical aspects of nature-based restoration features are presented in this study based on an example of a Californian gravel-cobbled bed river.

DOI: https://doi.org/10.3850/IAHR-39WC252171192022166

Year: 2022