The urban river restoration index (URRIX) - A supportive tool to assess fluvial environment improvement in urban flood control projects

摘要

River restoration is a strategy for controlling floods and restoring fluvial environmental quality. Urban river restoration is a challenge and involves a complex discussion, which needs to focus on the whole watershed and to recognize practical limits for restoration, balancing nature and city needs as much as possible. In this context, aiming to provide a practical tool to assess environmental effects in the flood control design process, the Urban River Restoration Index (URRIx) is proposed to quantify the effects of design alternatives, considering river restoration concepts in an urban watershed, giving an objective measure to help in decision making. Additionally, the URRIx can also be used to continuously monitor the river restoration successfulness over time, after a design alternative is implemented. The URRIx presents a multi-criteria formulation and ranges between 0 (the most negative result) and 1 (the most positive). A case study in the Rio de Janeiro metropolitan area (Brazil) was conducted to exemplify this discussion. The URRIx was applied to assess urban river improvement, through an integrated evaluation of flood reduction, urban revitalization, and river improvement. Outputs present a relevant space for considering urban river restoration - under given constraints - as a viable and valuable approach even in complex and fragile contexts. (C)2019 Elsevier Ltd. All rights reserved.