Publications (FIS)

Assessment of the integral recovery of an urban tropical watershed through the development and modeling of retrofitted multifunctional nature-based solutions scenarios

case study of th Quebrada Seca watershed, Costa Rica

authored by: Jose Ricardo Bonilla Brenes
supervised by: Jochen Hack
Abstract: Unplanned urban expansion in Latin America has significantly disrupted the natural hydrological processes of watersheds, particularly in tropical regions with extreme climatic conditions. This has led to substantial volumes of runoff, increasing the risk of flooding and necessitating large-scale engineering interventions to mitigate damage. Urbanization has not only exacerbated flooding issues but has also diminished green recreational spaces for residents and caused ecological degradation, negatively impacting the health of watersheds. This doctoral thesis presents a methodology aimed at improving the health of an urban tropical watershed in the search of its integral recovery, by creating scenarios for the implementation of multifunctional and retrofitted Nature-based Solutions (NbS). Those NbS scenarios utilize available spaces for NbS and consider existing land cover, complemented with insights from a co-design process of a Real-World Lab leveraging the multifunctionality of NbS to achieve hydrological, ecological, and social benefits, addressing the vulnerabilities of an urban tropical watershed. The case study focuses on an urban watershed located in Costa Rica's Greater Metropolitan Area (GAM), covering 23 km², with approximately 66% of its surface area impermeable. The proposed scenarios include using public roads in residential areas for the implementation of permeable pavements, bioretention cells, infiltration trenches, and street planters, while in industrial areas, suitable rooftops and parking lots are converted into green roofs and permeable pavements. Additionally, various public green spaces are transformed into multifunctional storage areas. Hydrological and hydraulic models were used to assess the performance of each scenario, while the increase in green space served as an indicator of ecological and social benefits. The simultaneous implementation of residential, industrial, and green space scenarios provides available surface area for NbS, potentially leading to a reduction in peak flow and runoff volume during specific precipitation events. Given that unregulated urban growth is a common feature of most urban watersheds in Latin America, this methodology, based on a co-design process and the use of different land cover types to create multifunctional retrofitted NbS scenarios; is transferable and adaptable to other tropical urban watersheds, as long as the local conditions of new study cases are taken into account.
Organisation(s): Institute of Environmental Planning
Type: Doctoral thesis
No. of pages: 175
Publication date: 26.02.2025
Publication status: Published
Sustainable Development Goals: SDG 11 - Sustainable Cities and Communities
Electronic version(s): https://doi.org/10.15488/18564 (Access: Open)

BibTeX

@phdthesis{f4bdcac5bd3246aaaff943e8c9fb0a48,
title = "Assessment of the integral recovery of an urban tropical watershed through the development and modeling of retrofitted multifunctional nature-based solutions scenarios: case study of th Quebrada Seca watershed, Costa Rica",
abstract = "Unplanned urban expansion in Latin America has significantly disrupted the natural hydrological processes of watersheds, particularly in tropical regions with extreme climatic conditions. This has led to substantial volumes of runoff, increasing the risk of flooding and necessitating large-scale engineering interventions to mitigate damage. Urbanization has not only exacerbated flooding issues but has also diminished green recreational spaces for residents and caused ecological degradation, negatively impacting the health of watersheds. This doctoral thesis presents a methodology aimed at improving the health of an urban tropical watershed in the search of its integral recovery, by creating scenarios for the implementation of multifunctional and retrofitted Nature-based Solutions (NbS). Those NbS scenarios utilize available spaces for NbS and consider existing land cover, complemented with insights from a co-design process of a Real-World Lab leveraging the multifunctionality of NbS to achieve hydrological, ecological, and social benefits, addressing the vulnerabilities of an urban tropical watershed. The case study focuses on an urban watershed located in Costa Rica's Greater Metropolitan Area (GAM), covering 23 km², with approximately 66% of its surface area impermeable. The proposed scenarios include using public roads in residential areas for the implementation of permeable pavements, bioretention cells, infiltration trenches, and street planters, while in industrial areas, suitable rooftops and parking lots are converted into green roofs and permeable pavements. Additionally, various public green spaces are transformed into multifunctional storage areas. Hydrological and hydraulic models were used to assess the performance of each scenario, while the increase in green space served as an indicator of ecological and social benefits. The simultaneous implementation of residential, industrial, and green space scenarios provides available surface area for NbS, potentially leading to a reduction in peak flow and runoff volume during specific precipitation events. Given that unregulated urban growth is a common feature of most urban watersheds in Latin America, this methodology, based on a co-design process and the use of different land cover types to create multifunctional retrofitted NbS scenarios; is transferable and adaptable to other tropical urban watersheds, as long as the local conditions of new study cases are taken into account.",
author = "{Bonilla Brenes}, {Jose Ricardo}",
year = "2025",
month = feb,
day = "26",
doi = "10.15488/18564",
language = "English",
publisher = "Leibniz Universit{\"a}t Hannover",
school = "Leibniz University Hannover",
}