Abstract Summary
The sustainable use and management of water resources for metropoles are becoming more challenging due to climate change, population growth, and land use change by urbanisation. For the metropole region Amsterdam, these impacts are evidenced by increased saltwater intrusion as well as more drought periods. Urban Greenery (UG) is seen as an indispensable infrastructural component for a liveable environment, as it offers a variety of socio-economic and environmental benefits like heat stress reduction, recreational opportunities, as well as rainwater buffer zones (Gemeente, 2020; Hansen, 2018; Jabbar et al., 2022; Stobbelaar et al., 2022). It is of great importance to sustain UG with adequate water resources, and hence emerged as an important policy agenda for cities like Amsterdam. The concept of Rainwater Harvesting (RWH) is seen as an interesting approach to sustain UG and its multi-functionalities, and subsequently alleviate (fresh)water scarcity at city scale (Jha et al., 2014; McCarton et al., 2021). Besides, integrating RWH measures as Nature-based Solutions (NbS) could provide additional co-benefits1. This research focuses on the development of a Planning Support System, which enables the long-term, climate adaptive planning of RWH measures to provide an alternative water source to sustain UG. The decision-support tool has the purpose to 1. Identify priority water demand areas and 2. Provide advise on suitable (Nature-based) RWH measures for the storage of rainwater. In order to plan rainwater reuse for sustaining Urban Green in the long term, a new conceptual framework was needed. This innovative framework links climate dynamics, RWH storage measures, and water demand of UG. The framework is applicable at city scale and overcomes long term planning by accounting for climate scenarios for a specific outlook year. The first goal focuses on distinguishing the species-specific water demand of UG and identify the temporal water balance for specific climate scenarios. The second goal focuses on providing advise on suitable RWH locations by identifying the spatial/physical characteristics of the area and assessing a selection of RWH measures on their performances. Altogether, the tool provides an overview on which (Nature-based) RWH measures can to what extent provide rainwater in periods of drought in a certain scenario. The framework and planning support system will be validated and operationalized by applying them on defined case areas within Amsterdam and generate an overview for decision-makers on what interventions can be made regarding sustaining urban green and increasing climate resilience within the city.
