TY - GEN

T1 - Integrated development of Nature-Based Solutions (NBS) for tropical urban watershed restoration

AU - Bonilla Brenes, José Ricardo

AU - Morales Mora, Martín

AU - Vega, Rafael Oreamuno

AU - Hack, Jochen

PY - 2023

Y1 - 2023

N2 - Unplanned urban growth has been a recurrent problem affecting the hydrological watershed response, especially in tropical countries with short rainfall durations and high rainfall intensities. Uncontrolled urban growth complemented with extreme rainfall conditions causes high runoff volumes that require large-scale engineering interventions for proper management. This study aims to develop integral-multifunctional naturebased solution (NBS) scenarios to aid the hydrological, ecological and social recovery of urban watersheds in tropical areas and promote the fulfillment of the 2030 milestones of the United Nations Sustainable Development Goals (SDGs). A tropical watershed (23 km²) located in the Greater Metropolitan Area of Costa Rica was investigated regarding the spatio-temporal urbanization process between 1945 and 2019, based on remote sensing data and its hydrological response. The analysis of the urbanization process of the watershed (+64% urban) allowed identifying severe alterations of the hydrological cycle resulting in runoff volume increases (80%), peak flow and peak specific discharge increase (250%), and a time to peak reduction (25 minutes), triggering flooding problems. Once the problem was identified, integral NBS implementation scenarios were developed, based on their performance, space availability, and strategic location within the watershed to provide multiple functions, evaluating the level of recovery that could be achieved. For the development of the scenarios, some of the hydrological, ecological, social, economic and political benefits provided by NBS were analyzed. The available space was evaluated, based on the current land cover classification and its urban configuration, defining the potential for NBS implementation, both in residential and industrial areas. Specific opportunities and needs for increasing social and ecological connectivity through NBS were considered. This scenario building tool aims to develop a comprehensive replicable methodology for the recovery of urban tropical watersheds and promote better progress in the pursuit of meeting the 2030 milestones of the United Nations SDGs.

AB - Unplanned urban growth has been a recurrent problem affecting the hydrological watershed response, especially in tropical countries with short rainfall durations and high rainfall intensities. Uncontrolled urban growth complemented with extreme rainfall conditions causes high runoff volumes that require large-scale engineering interventions for proper management. This study aims to develop integral-multifunctional naturebased solution (NBS) scenarios to aid the hydrological, ecological and social recovery of urban watersheds in tropical areas and promote the fulfillment of the 2030 milestones of the United Nations Sustainable Development Goals (SDGs). A tropical watershed (23 km²) located in the Greater Metropolitan Area of Costa Rica was investigated regarding the spatio-temporal urbanization process between 1945 and 2019, based on remote sensing data and its hydrological response. The analysis of the urbanization process of the watershed (+64% urban) allowed identifying severe alterations of the hydrological cycle resulting in runoff volume increases (80%), peak flow and peak specific discharge increase (250%), and a time to peak reduction (25 minutes), triggering flooding problems. Once the problem was identified, integral NBS implementation scenarios were developed, based on their performance, space availability, and strategic location within the watershed to provide multiple functions, evaluating the level of recovery that could be achieved. For the development of the scenarios, some of the hydrological, ecological, social, economic and political benefits provided by NBS were analyzed. The available space was evaluated, based on the current land cover classification and its urban configuration, defining the potential for NBS implementation, both in residential and industrial areas. Specific opportunities and needs for increasing social and ecological connectivity through NBS were considered. This scenario building tool aims to develop a comprehensive replicable methodology for the recovery of urban tropical watersheds and promote better progress in the pursuit of meeting the 2030 milestones of the United Nations SDGs.

KW - Costa Rica

KW - flooding

KW - Land cover change

KW - Nature-based solutions

KW - Urbanization

UR - http://www.scopus.com/inward/record.url?scp=85187682496&partnerID=8YFLogxK

U2 - 10.3850/978-90-833476-1-5_iahr40wc-p1202-cd

DO - 10.3850/978-90-833476-1-5_iahr40wc-p1202-cd

M3 - Conference contribution

AN - SCOPUS:85187682496

SN - 9789083347615

T3 - Proceedings of the IAHR World Congress

SP - 2720

EP - 2729

BT - Proceedings of the 40th IAHR World Congress

A2 - Habersack, Helmut

A2 - Tritthart, Michael

A2 - Waldenberger, Lisa

T2 - 40th IAHR World Congress, 2023

Y2 - 21 August 2023 through 25 August 2023

ER -